title: Yayati

text: Eventually, Devayani learns of her husband's affair with Sharmishtha, and complains to her father. Enraged at his son-in-law's disobedience, Shukracharya curses Yayāti with premature old age in punishment for inflicting such pain upon his daughter. However, on learning Sharmishtha's desire to become a mother, he later relents, telling Yayāti that if he could persuade one of his (Yayāti's) sons to swap ages with him, he will be able to escape the curse, and regain his lost youth for a while. Yayāti asks his sons if one of them would give up his youth to rejuvenate his father, but all refuse except the youngest, Puru (one of his sons by Sharmishtha). In grateful recognition of Puru's filial devotion, Yayāti makes him his legitimate heir, and it is from the line of Puru - later King Puru - that the Kuruvamsha (Kuru dynasty) later arises.


title: Yayati

text: In the words of the story, Yayāti enjoys all the pleasures of the senses 'for a thousand years' and, by experiencing passion to the full, comes to realise its utter futility, saying: "Know this for certain... not all the food, wealth and women of the world can appease the lust of a single man of uncontrolled senses. Craving for sense-pleasures is not removed but aggravated by indulgence even as ghee poured into fire increases it...One who aspires to peace and happiness should instantly renounce craving and seek instead that which neither grows old, nor ceases - no matter how old the body may become." Having found wisdom by following the road of excess, Yayāti gratefully returns the youth of his son Puru, and takes back his old age in return, renouncing the world to spend his remaining days as a forest ascetic. His spiritual practices are, at long last, blessed with success and, alone in the deep woods, he is rewarded with ascension to "Svarga" - the heavenly realm of the righteous, ruled by Indra, that is but one step below the ultimate liberation of "moksha".


title: Yayati

text: Yayati ascended to heaven due to his virtues. He was so virtuous that he could travel many celestial regions. Sometimes, he went to the region of Brahma and sometimes stayed at Amaravati, the region of Indra. One day, when Yayati and Indra were conversing, Indra asked him questions. Indra asked him how many sacrifices he did and whom he was equal to in sacrifices. Yayati boastingly said the number of his sacrifices was innumerable, and proclaimed his superiority. Indra was angered by this bragging, and threw Yayati out of heaven. Yayati begged his pardon, so Indra said even though he would be thrown out of heaven, he would fall amidst virtuous and wise humans. Thus, while Yayati fell from the celestial region, he got stuck in the firmament. His grandsons: Ashtaka, Vasuman, Prattarddana, and Sivi (kings and sons of Mamata or Madhavi) met him. They enquired who he was, and why he was thus. They asked about heaven, about hell, about rebirth. Yayati recited everything. Then, out of compassion, they offered their own meritorious powers to Yayati. With these merits, Yayati attained again the realm of heaven. Five golden chariots arrived and took them to the region of eternal bliss, because of the merits of his grandsons and his own.


title: Yayati

text: Another one of his descendants (through Puru) was King Bharata, the son of King Dushyanta and Shakuntala. Further descendants were part of the Kuru Kingdom, including Shantanu, Dhritarashtra, Pandu, Yudhishthira, Abhimanyu, and Parikshit.


title: Yayati

text: In modern language and usage, trading conscientious behaviour for external gain is sometimes called Yayāti Syndrome.


title: Yayati

text: "Yayati", a Marathi novel by V. S. Khandekar, won him the Sahitya Akademi Award (1960), and a Jnanpith Award (1974).


title: Yayati

text: Playwright Girish Karnad's debut play "Yayati" (1961) is based on the story of King Yayāti found in the "Mahabharata".


title: Mortal Kombat vs. DC Universe

text: Mortal Kombat vs. DC Universe is a 2008 fighting video game, developed and published by Midway Games. The last entry in the franchise before the company went bankrupt in 2009 and sold the franchise to Warner Bros. Interactive Entertainment. Is a crossover between "Mortal Kombat" and the DC Universe, is also the eighth main installment in the "Mortal Kombat" franchise, set in an alternate timeline between "Mortal Kombat II" and "Mortal Kombat 3" and despite the story not being connected to the first seven games or any other game that was released after this one. The game was released on November 16, 2008 and contains characters from both franchises. Its story was written by comic writers Jimmy Palmiotti and Justin Gray. The game was followed by a "Mortal Kombat" reboot in 2011 and by "" in 2013.


title: Mortal Kombat vs. DC Universe

text: The game takes place after Raiden, Earthrealm's god of thunder, and Superman, Metropolis' defender, repel invasions from both their worlds. An attack by both Raiden and Superman simultaneously in their separate universes causes the merging of the "Mortal Kombat" and DC villains, Shao Kahn and Darkseid, resulting in the creation of Dark Kahn, whose mere existence causes the two universes to begin merging; if allowed to continue, it would result in the destruction of both. Characters from both universes begin to fluctuate in power, becoming stronger or weaker.


title: Mortal Kombat vs. DC Universe

text: "Mortal Kombat vs. DC Universe" was developed using Epic Games' Unreal Engine 3 and is available for the PlayStation 3 and Xbox 360 platforms. It is the first "Mortal Kombat" title developed solely for the seventh generation of video game consoles. Most reviewers agreed that "Mortal Kombat vs. DC Universe" was entertaining and made good use of its DC Universe license, but the game's lack of unlockable features as opposed to past installments of "Mortal Kombat" and toned-down finishing moves garnered some criticism.


title: Mortal Kombat vs. DC Universe

text: The game features a story mode, playable from two different perspectives. The perspectives consist of one segment from the DC Universe side, and one from the "Mortal Kombat" side, each split up into various chapters. Depending on which side players choose, the characters from one universe see those from the opposite universe as the invaders of their own. The player has the ability to play as all the characters in the story mode at one point during development, but the story mode ultimately lacked story arcs for a few characters. "Mortal Kombat vs. DC Universe" also contains a mode called "Kombo Challenge", where players must perform ten pre-created combos of increasing difficulty.


title: Mortal Kombat vs. DC Universe

text: Intertwined within fight matches, which are played in a 3D fighter style, are new gameplay modes, such as "Free-Fall Kombat" or "Falling Kombat," which are activated automatically after throwing the opponent to a lower level in the arena. The players can fight in the air during the fall in a quasi-mini-game, with one player having to hit certain buttons to be above the other during the fall and land on the other player when the fall ends. "Klose Kombat" is a mode the players can enter during a fight, causing the characters to lock with each other and the perspective to change to a close-up shot of the two, to make for an interval of close-quarters fighting. A "Test Your Might" mini-game is also worked into the gameplay; while fighting in certain areas, the player can smash the opponent through a series of walls and engage in a tug-of-war with the damage meter at the top of the screen. The player on the offense presses buttons to increase damage given, while the player on the defense presses buttons to decrease damage taken.


title: Mortal Kombat vs. DC Universe

text: Another in-fight feature called "Rage mode" is introduced in "Mortal Kombat vs. DC Universe". The Rage mode is governed by a rage meter placed below the player's health meter that fills progressively every time the player receives damage or attacks. Once the meter is completely filled, Rage mode can be activated and lasts for several seconds. Rage mode enables the player to break the opponent's guard on the second hit, prevents the attacker from experiencing hit stun, knockdown or pop-up, and increases the damage of an attacker's moves. During fights, characters show permanent signs of damage, such as bruises, scrapes, bleeding, and broken or torn clothing. All of the characters except Darkseid, Shao Kahn, and Dark Kahn have finishing moves; the "Mortal Kombat" characters and the DC villains can execute Fatalities, while the DC heroes can execute moves called "heroic brutalities," which function in the same manner but do not kill opponents, in order to stay in tone with the heroes who have an established reputation of never taking a life.


title: Mortal Kombat vs. DC Universe

text: After Shao Kahn's invasion of Earthrealm is halted by Raiden's forces of light, Raiden blasts and sends Kahn through a portal. At exactly the same time on Earth, Superman stops Darkseid's Apokoliptian invasion by blasting Darkseid with his heat vision as he enters a boom tube. These acts do not destroy either of them, but merge them into Dark Kahn, and causes the DC and "Mortal Kombat" universes to merge. As this happens, the characters' abilities fluctuate, causing violent "rage" outbreaks that are actually the feelings of Dark Kahn being infused in the characters from afar. Because of this, certain characters gain either strength or vulnerability. This allows for such things as the possibility of Superman being defeated due to his vulnerability to magic, and giving the Joker the ability to fight skilled martial artists such as his nemesis Batman and Deathstroke. With each world thinking that the other is responsible for the merger, they fight each other until only one fighter from each side remains: Raiden and Superman. In the final battle, the two fight while Dark Kahn feeds on their rage. Both realizing that neither is working with Dark Kahn, Raiden and Superman overcome their rage for each other and defeat their fused enemy, restoring the two worlds to their normal separation. While everyone else has been sent to their original universe, Darkseid and Shao Kahn have been switched and are both rendered powerless. In the end, they both face eternal imprisonment in the other's universe; Darkseid is restrained in the Netherrealm, while Shao Kahn is trapped in the Phantom Zone.


title: Mortal Kombat vs. DC Universe

text: MK's Quan Chi & Kung Lao and DC's Harley Quinn & Doomsday were going to be added into game by DLC but got canceled.


title: Mortal Kombat vs. DC Universe

text: "Mortal Kombat vs. DC Universe" was Midway Games's last project before filing for bankruptcy and selling the rights to Warner Bros. Interactive Entertainment in 2009. In February 2007, Midway Games announced they were planning a new game in the "Mortal Kombat" franchise, inspired by seeing a showcase of "Gears of War". ""Mortal Kombat 8"" would have been "dark, gritty, serious" and a "back to basics reboot" of the series. Eventually, during the planning process, a deal with DC Comics was made and this project was cancelled, thus leading to the development of a different game. An announcement in April 2008 confirmed the game as a crossover, and a trailer was released. The only notable aspect that remained from the original project was the use of the Unreal Engine 3, also used in "Gears of War".


title: Mortal Kombat vs. DC Universe

text: "Mortal Kombat vs. DC Universe" was co-published by Midway Games and Warner Bros. Interactive Entertainment and was the final "Mortal Kombat" title to be developed under the Midway label prior to its purchase by Warner Bros. Interactive. Midway used AutoDesk software to develop "Mortal Kombat vs DC Universe", according to Maurice Patel, entertainment industry manager at AutoDesk, and Illuminate Labs products for lighting.


title: Mortal Kombat vs. DC Universe

text: The use of a DC license imposed some restrictions on the characteristic violence in "Mortal Kombat" games. "Mortal Kombat vs. DC Universe" was thus restricted to a "Teen" ESRB rating. Therefore, certain Fatalities such as Sub-Zero's "Spine Rip" were excluded or replaced due to their graphic nature. In order to keep that rating, two of the Fatalities in the game were censored in North America. In the United Kingdom version, both the Joker and Deathstroke's first Fatality depict them each finishing their opponent with a gunshot to the head, both shown uncut from a distance. The North American version has the camera quickly pan toward the victor before the shot is fired, thereby cutting the victim out of the shot completely. Additionally, one of Kitana's Fatalities which involved impaling the opponent in the head and the torso with her fanblades was modified so that both fanblades impaled her opponent's chest instead.


title: Mortal Kombat vs. DC Universe

text: According to interviews, the characters were chosen for their popularity, and for parallels between them from both universes. Ed Boon, creative director of "Mortal Kombat vs. DC Universe" and co-creator of the "Mortal Kombat" franchise, has said that some of the characters' abilities, especially those from the DC Universe, had been toned down to make them balanced within "Mortal Kombat vs. DC Universe". For example, Boon specifically mentioned that Superman became vulnerable because of magic. Boon revealed that two new characters were developed as downloadable content, Quan Chi from "Mortal Kombat" and Harley Quinn from DC comics but had been discarded. He had also hinted earlier at the prospect of Kung Lao and Doomsday being downloadable characters.


title: Mortal Kombat vs. DC Universe

text: For the release of the "Kollector's Edition" of "Mortal Kombat vs. DC Universe", a new cover was created by Alex Ross. Also included in the "Kollector's Edition" is a 16-page comic book prequel, "Beginnings", which was illustrated by "Mortal Kombat" co-creator John Tobias.


title: Mortal Kombat vs. DC Universe

text: Downloadable content (DLC) had been confirmed by Major Nelson, but was canceled due to Midway's financial issues. Ed Boon had stated that they would have been updating "Mortal Kombat vs. DC Universe" periodically with new content all the way up to the release of the next installment of the "Mortal Kombat" series: "I'd like to have [DLC] as soon as possible. I think that might be a great Christmas gift to reinvigorate the game". Ed Boon said on his Twitter account that the plan for DLC had been scrapped, which occurred because, as clarified by 1UP, Midway had filed for bankruptcy and was purchased by Warner Bros. Interactive after the suggestion of downloadable content.


title: Mortal Kombat vs. DC Universe

text: "Mortal Kombat vs. DC Universe" received mixed to positive reviews from critics. Adam Sessler of X-Play stated: "Whether it's a decade-late answer to the "Marvel vs. Capcom" team up games or an off-the-cuff boardroom joke gone wildly too far, "Mortal Kombat vs. DC Universe" is destined to make just about anyone's shortlist of bizarre video game team-ups. Still, sometimes two disparate things can merge to create a unique synergy that makes the melding work, however unlikely it may have seemed at the outset." In "GamePro", Sid Shuman called it "surprisingly enjoyable." Wired.com's preview stated that the concept of the game was "nose-pokingly ludicrous", noting that Superman's powers could be used to easily defeat a character with the comment, "from Sub-Zero to Well-Done in eight seconds flat." ABC News praised the game's story because it did "a great job of giving players a cohesive, if far-fetched, story line that's fun if not engaging," as well as "comic book-like" dialogue. "Mortal Kombat vs. DC Universe"s Kombo Challenge mode was criticized as a thin and frustrating mode with combos that required very precise timing. The modes of Klose Kombat and Free-Fall Kombat were praised as concepts but were criticized in their execution as they appeared to slow the gameplay down and took the player out of the fast gameplay experience. Critics noted that the change in the amount of gore was disappointing to longtime fans of the series who were used to the "insane amounts of gore."


title: Mortal Kombat vs. DC Universe

text: The American Academy of Child and Adolescent Psychiatry approved of "Mortal Kombat vs. DC Universe" because of its departure from the earlier M-rated games of the series praising its "simpler play, familiar graphics and adjustable gore content" but still not recommending it for younger players. In 2008, "GamePro", ranked it as the 15th best fighting game out of 18.


title: Mortal Kombat vs. DC Universe

text: Midway Games announced that as of January 26, 2009, "Mortal Kombat vs. DC Universe" had shipped 1.8 million copies since its release in mid-November 2008, not including the sales of the "Kollector's Edition". The chief operating officer of GameStop stated that the "Kollector's Edition" of "Mortal Kombat vs. DC Universe" made up 55% of the game's total sales at GameStop locations in its first week. In their 10-K filing, Midway Games revealed the title had sold over 1.9 million units, making it one of the company's most successful titles since 2002. According to Wired.com, "Mortal Kombat vs. DC Universe" also "holds the distinction of being the most pre-ordered "MK" game of all time." In a ranking by Rentrak, the Xbox 360 version of "Mortal Kombat vs. DC Universe" was the sixth most rented game of 2009.


title: Mortal Kombat vs. DC Universe

text: Midway's work on "Mortal Kombat vs. DC Universe's" cinematic story mode would influence development of future "Mortal Kombat" games and the "Injustice" series after Midway filed for Chapter 11 bankruptcy and became NetherRealm Studios. Future fighting games like "Guilty Gear Xrd", "Street Fighter V", "Tekken 7", and "" attempted to create similar film-like experiences.


title: Fuzzing

text: In programming and software development, fuzzing or fuzz testing is an automated software testing technique that involves providing invalid, unexpected, or random data as inputs to a computer program. The program is then monitored for exceptions such as crashes, failing built-in code assertions, or potential memory leaks. Typically, fuzzers are used to test programs that take structured inputs. This structure is specified, e.g., in a file format or protocol and distinguishes valid from invalid input. An effective fuzzer generates semi-valid inputs that are "valid enough" in that they are not directly rejected by the parser, but do create unexpected behaviors deeper in the program and are "invalid enough" to expose corner cases that have not been properly dealt with.


title: Fuzzing

text: For the purpose of security, input that crosses a trust boundary is often the most useful. For example, it is more important to fuzz code that handles the upload of a file by any user than it is to fuzz the code that parses a configuration file that is accessible only to a privileged user.


title: Fuzzing

text: The term "fuzz" originates from a fall 1988 class project in the graduate Advanced Operating Systems class (CS736), taught by Prof. Barton Miller at the University of Wisconsin, whose results were subsequently published in 1990. To fuzz test a UNIX utility meant to automatically generate random input and command-line parameters for the utility. The project was designed to test the reliability of UNIX command line programs by executing a large number of random inputs in quick succession until they crashed. Miller's team was able to crash 25 to 33 percent of the utilities that they tested. They then debugged each of the crashes to determine the cause and categorized each detected failure. To allow other researchers to conduct similar experiments with other software, the source code of the tools, the test procedures, and the raw result data were made publicly available. This early fuzzing would now be called black box, generational, unstructured (dumb) fuzzing.


title: Fuzzing

text: This 1990 fuzz paper also noted the relationship of reliability to security: "Second, one of the bugs that we found was caused by the same programming practice that provided one of the security holes to the Internet worm (the 'gets finger' bug). We have found additional bugs that might indicate future security holes." (Referring to the Morris worm of November 1988.)


title: Fuzzing

text: The original fuzz project went on to make contributions in 1995, 2000, 2006 and most recently in 2020:


title: Fuzzing

text: In April 2012, Google announced ClusterFuzz, a cloud-based fuzzing infrastructure for security-critical components of the Chromium web browser. Security researchers can upload their own fuzzers and collect bug bounties if ClusterFuzz finds a crash with the uploaded fuzzer.


title: Fuzzing

text: In September 2014, Shellshock was disclosed as a family of security bugs in the widely used UNIX Bash shell; most vulnerabilities of Shellshock were found using the fuzzer AFL. (Many Internet-facing services, such as some web server deployments, use Bash to process certain requests, allowing an attacker to cause vulnerable versions of Bash to execute arbitrary commands. This can allow an attacker to gain unauthorized access to a computer system.)


title: Fuzzing

text: In April 2015, Hanno Böck showed how the fuzzer AFL could have found the 2014 Heartbleed vulnerability. (The Heartbleed vulnerability was disclosed in April 2014. It is a serious vulnerability that allows adversaries to decipher otherwise encrypted communication. The vulnerability was accidentally introduced into OpenSSL which implements TLS and is used by the majority of the servers on the internet. Shodan reported 238,000 machines still vulnerable in April 2016; 200,000 in January 2017.)


title: Fuzzing

text: In August 2016, the Defense Advanced Research Projects Agency (DARPA) held the finals of the first Cyber Grand Challenge, a fully automated capture-the-flag competition that lasted 11 hours. The objective was to develop automatic defense systems that can discover, exploit, and correct software flaws in real-time. Fuzzing was used as an effective offense strategy to discover flaws in the software of the opponents. It showed tremendous potential in the automation of vulnerability detection. The winner was a system called "Mayhem" developed by the team ForAllSecure led by David Brumley.


title: Fuzzing

text: In September 2016, Microsoft announced Project Springfield, a cloud-based fuzz testing service for finding security critical bugs in software.


title: Fuzzing

text: In December 2016, Google announced OSS-Fuzz which allows for continuous fuzzing of several security-critical open-source projects.


title: Fuzzing

text: At Black Hat 2018, Christopher Domas demonstrated the use of fuzzing to expose the existence of a hidden RISC core in a processor. This core was able to bypass existing security checks to execute Ring 0 commands from Ring 3.


title: Fuzzing

text: In September 2020, Microsoft released OneFuzz, a self-hosted fuzzing-as-a-service platform that automates the detection of software bugs. It supports Windows and Linux.


title: Fuzzing

text: Testing programs with random inputs dates back to the 1950s when data was still stored on punched cards. Programmers would use punched cards that were pulled from the trash or card decks of random numbers as input to computer programs. If an execution revealed undesired behavior, a bug had been detected.


title: Fuzzing

text: In 1981, Duran and Ntafos formally investigated the effectiveness of testing a program with random inputs. While random testing had been widely perceived to be the worst means of testing a program, the authors could show that it is a cost-effective alternative to more systematic testing techniques.


title: Fuzzing

text: In 1983, Steve Capps at Apple developed "The Monkey", a tool that would generate random inputs for classic Mac OS applications, such as MacPaint. The figurative "monkey" refers to the infinite monkey theorem which states that a monkey hitting keys at random on a typewriter keyboard for an infinite amount of time will eventually type out the entire works of Shakespeare. In the case of testing, the monkey would write the particular sequence of inputs that would trigger a crash.


title: Fuzzing

text: In 1991, the crashme tool was released, which was intended to test the robustness of Unix and Unix-like operating systems by randomly executing systems calls with randomly chosen parameters.


title: Fuzzing

text: A mutation-based fuzzer leverages an existing corpus of seed inputs during fuzzing. It generates inputs by modifying (or rather mutating) the provided seeds. For example, when fuzzing the image library libpng, the user would provide a set of valid PNG image files as seeds while a mutation-based fuzzer would modify these seeds to produce semi-valid variants of each seed. The corpus of seed files may contain thousands of potentially similar inputs. Automated seed selection (or test suite reduction) allows users to pick the best seeds in order to maximize the total number of bugs found during a fuzz campaign.


title: Fuzzing

text: A generation-based fuzzer generates inputs from scratch. For instance, a smart generation-based fuzzer takes the input model that was provided by the user to generate new inputs. Unlike mutation-based fuzzers, a generation-based fuzzer does not depend on the existence or quality of a corpus of seed inputs.


title: Fuzzing

text: Some fuzzers have the capability to do both, to generate inputs from scratch and to generate inputs by mutation of existing seeds.


title: Fuzzing

text: Typically, fuzzers are used to generate inputs for programs that take structured inputs, such as a file, a sequence of keyboard or mouse events, or a sequence of messages. This structure distinguishes valid input that is accepted and processed by the program from invalid input that is quickly rejected by the program. What constitutes a valid input may be explicitly specified in an input model. Examples of input models are formal grammars, file formats, GUI-models, and network protocols. Even items not normally considered as input can be fuzzed, such as the contents of databases, shared memory, environment variables or the precise interleaving of threads. An effective fuzzer generates semi-valid inputs that are "valid enough" so that they are not directly rejected from the parser and "invalid enough" so that they might stress corner cases and exercise interesting program behaviours.


title: Fuzzing

text: A smart (model-based, grammar-based, or protocol-based) fuzzer leverages the input model to generate a greater proportion of valid inputs. For instance, if the input can be modelled as an abstract syntax tree, then a smart mutation-based fuzzer would employ random transformations to move complete subtrees from one node to another. If the input can be modelled by a formal grammar, a smart generation-based fuzzer would instantiate the production rules to generate inputs that are valid with respect to the grammar. However, generally the input model must be explicitly provided, which is difficult to do when the model is proprietary, unknown, or very complex. If a large corpus of valid and invalid inputs is available, a grammar induction technique, such as Angluin's L* algorithm, would be able to generate an input model.


title: Fuzzing

text: A dumb fuzzer does not require the input model and can thus be employed to fuzz a wider variety of programs. For instance, AFL is a dumb mutation-based fuzzer that modifies a seed file by flipping random bits, by substituting random bytes with "interesting" values, and by moving or deleting blocks of data. However, a dumb fuzzer might generate a lower proportion of valid inputs and stress the parser code rather than the main components of a program. The disadvantage of dumb fuzzers can be illustrated by means of the construction of a valid checksum for a cyclic redundancy check (CRC). A CRC is an error-detecting code that ensures that the integrity of the data contained in the input file is preserved during transmission. A checksum is computed over the input data and recorded in the file. When the program processes the received file and the recorded checksum does not match the re-computed checksum, then the file is rejected as invalid. Now, a fuzzer that is unaware of the CRC is unlikely to generate the correct checksum. However, there are attempts to identify and re-compute a potential checksum in the mutated input, once a dumb mutation-based fuzzer has modified the protected data.


title: Fuzzing

text: Typically, a fuzzer is considered more effective if it achieves a higher degree of code coverage. The rationale is, if a fuzzer does not exercise certain structural elements in the program, then it is also not able to reveal bugs that are hiding in these elements. Some program elements are considered more critical than others. For instance, a division operator might cause a division by zero error, or a system call may crash the program.


title: Fuzzing

text: A black-box fuzzer treats the program as a black box and is unaware of internal program structure. For instance, a random testing tool that generates inputs at random is considered a blackbox fuzzer. Hence, a blackbox fuzzer can execute several hundred inputs per second, can be easily parallelized, and can scale to programs of arbitrary size. However, blackbox fuzzers may only scratch the surface and expose "shallow" bugs. Hence, there are attempts to develop blackbox fuzzers that can incrementally learn about the internal structure (and behavior) of a program during fuzzing by observing the program's output given an input. For instance, LearnLib employs active learning to generate an automaton that represents the behavior of a web application.


title: Fuzzing

text: A white-box fuzzer leverages program analysis to systematically increase code coverage or to reach certain critical program locations. For instance, SAGE leverages symbolic execution to systematically explore different paths in the program.


title: Fuzzing

text: If the program's specification is available, a whitebox fuzzer might leverage techniques from model-based testing to generate inputs and check the program outputs against the program specification.


title: Fuzzing

text: A whitebox fuzzer can be very effective at exposing bugs that hide deep in the program. However, the time used for analysis (of the program or its specification) can become prohibitive. If the whitebox fuzzer takes relatively too long to generate an input, a blackbox fuzzer will be more efficient. Hence, there are attempts to combine the efficiency of blackbox fuzzers and the effectiveness of whitebox fuzzers.


title: Fuzzing

text: A gray-box fuzzer leverages instrumentation rather than program analysis to glean information about the program. For instance, AFL and libFuzzer utilize lightweight instrumentation to trace basic block transitions exercised by an input. This leads to a reasonable performance overhead but informs the fuzzer about the increase in code coverage during fuzzing, which makes gray-box fuzzers extremely efficient vulnerability detection tools.


title: Fuzzing

text: Fuzzing is used mostly as an automated technique to expose vulnerabilities in security-critical programs that might be exploited with malicious intent. More generally, fuzzing is used to demonstrate the presence of bugs rather than their absence. Running a fuzzing campaign for several weeks without finding a bug does not prove the program correct. After all, the program may still fail for an input that has not been executed, yet; executing a program for all inputs is prohibitively expensive. If the objective is to prove a program correct for all inputs, a formal specification must exist and techniques from formal methods must be used.


title: Fuzzing

text: In order to expose bugs, a fuzzer must be able to distinguish expected (normal) from unexpected (buggy) program behavior. However, a machine cannot always distinguish a bug from a feature. In automated software testing, this is also called the test oracle problem.


title: Fuzzing

text: Typically, a fuzzer distinguishes between crashing and non-crashing inputs in the absence of specifications and to use a simple and objective measure. Crashes can be easily identified and might indicate potential vulnerabilities (e.g., denial of service or arbitrary code execution). However, the absence of a crash does not indicate the absence of a vulnerability. For instance, a program written in C may or may not crash when an input causes a buffer overflow. Rather the program's behavior is undefined.


title: Fuzzing

text: To make a fuzzer more sensitive to failures other than crashes, sanitizers can be used to inject assertions that crash the program when a failure is detected. There are different sanitizers for different kinds of bugs:


title: Fuzzing

text: Fuzzing can also be used to detect "differential" bugs if a reference implementation is available. For automated regression testing, the generated inputs are executed on two versions of the same program. For automated differential testing, the generated inputs are executed on two implementations of the same program (e.g., lighttpd and httpd are both implementations of a web server). If the two variants produce different output for the same input, then one may be buggy and should be examined more closely.


title: Fuzzing

text: Static program analysis analyzes a program without actually executing it. This might lead to false positives where the tool reports problems with the program that do not actually exist. Fuzzing in combination with dynamic program analysis can be used to try to generate an input that actually witnesses the reported problem.


title: Fuzzing

text: Modern web browsers undergo extensive fuzzing. The Chromium code of Google Chrome is continuously fuzzed by the Chrome Security Team with 15,000 cores. For Microsoft Edge and Internet Explorer, Microsoft performed fuzzed testing with 670 machine-years during product development, generating more than 400 billion DOM manipulations from 1 billion HTML files.


title: Fuzzing

text: A fuzzer produces a large number of inputs in a relatively short time. For instance, in 2016 the Google OSS-fuzz project produced around 4 trillion inputs a week. Hence, many fuzzers provide a toolchain that automates otherwise manual and tedious tasks which follow the automated generation of failure-inducing inputs.


title: Fuzzing

text: Automated bug triage is used to group a large number of failure-inducing inputs by root cause and to prioritize each individual bug by severity. A fuzzer produces a large number of inputs, and many of the failure-inducing ones may effectively expose the same software bug. Only some of these bugs are security-critical and should be patched with higher priority. For instance the CERT Coordination Center provides the Linux triage tools which group crashing inputs by the produced stack trace and lists each group according to their probability to be exploitable. The Microsoft Security Research Centre (MSEC) developed the !exploitable tool which first creates a hash for a crashing input to determine its uniqueness and then assigns an exploitability rating:


title: Fuzzing

text: Previously unreported, triaged bugs might be automatically reported to a bug tracking system. For instance, OSS-Fuzz runs large-scale, long-running fuzzing campaigns for several security-critical software projects where each previously unreported, distinct bug is reported directly to a bug tracker. The OSS-Fuzz bug tracker automatically informs the maintainer of the vulnerable software and checks in regular intervals whether the bug has been fixed in the most recent revision using the uploaded minimized failure-inducing input.


title: Fuzzing

text: Automated input minimization (or test case reduction) is an automated debugging technique to isolate that part of the failure-inducing input that is actually inducing the failure. If the failure-inducing input is large and mostly malformed, it might be difficult for a developer to understand what exactly is causing the bug. Given the failure-inducing input, an automated minimization tool would remove as many input bytes as possible while still reproducing the original bug. For instance, Delta Debugging is an automated input minimization technique that employs an extended binary search algorithm to find such a minimal input.


title: Norman Maclean

text: Norman Fitzroy Maclean (December 23, 1902August 2, 1990) was a Scottish-American professor at the University of Chicago who became, following his retirement, a major figure in American literature. Maclean is best known for his collection of novellas "A River Runs Through It and Other Stories" (1976) and the creative nonfiction book "Young Men and Fire" (1992).


title: Norman Maclean

text: In his novella, "A River Runs Through It", Norman Maclean alleged that his paternal ancestors were from the Isle of Mull, in the Inner Hebrides of Scotland. According to his son, however, their paternal ancestors were Gaelic speaking Presbyterians and from the Isle of Coll, which is "located about seven miles west of the Clan MacLean stronghold, the Isle of Mull".


title: Norman Maclean

text: The author's great-grandfather, Laughlan Maclean, was a carpenter by trade and emigrated to Cape Breton, Nova Scotia in 1821, before settling on a homestead in Pictou County. Laughlan Maclean was accompanied by his wife, Elizabeth Campbell.


title: Norman Maclean

text: Norman's father, Rev. John Norman Maclean, was born to Laughlan's son Norman and his wife Mary MacDonald on the family farm in the Canadian Gaelic-speaking community of Marshy Hope, Pictou County, Nova Scotia on July 28, 1862.


title: Norman Maclean

text: Showing signs of academic promise, John Norman Maclean trained for the ministry first at Pictou Academy, where academic records refer to him as "J.N. Mclean of Glenbard", a community famous as the last home and burial place of the Canadian Gaelic poet John MacLean, the former Chief Bard () to the Chief of Clan MacLean of Coll, who remains a major figure in Scottish Gaelic literature.


title: Norman Maclean

text: John Maclean completed his education at Dalhousie College in Halifax and at Manitoba College in Winnipeg. While riding circuit in the summers among the many small Presbyterian congregations in the pioneer communities of the Pembina Valley Region of Manitoba, MacLean met his future wife, an English-Canadian schoolmarm named Clara Davidson.


title: Norman Maclean

text: Clara's father, John Davidson, was a Presbyterian immigrant from Northern England, and had settled first near Argenteuil, Laurentides, Quebec, where his daughter Clara had been born. Finding the farmland there to be poor, however, John Davidson and his family had moved west by oxcart and settled on a homestead at New Haven, near Manitou, Manitoba.


title: Norman Maclean

text: During their courtship, Clara often accompanied John while he was riding circuit. In 1893, John Norman Maclean completed advanced studies at San Francisco Theological Seminary in San Anselmo, California and was ordained as a Presbyterian minister. John and Clara Maclean were married in Pembina, Manitoba on August 1, 1893.


title: Norman Maclean

text: Norman Maclean was born at Clarinda, Iowa, on December 23, 1902, and was the son of Clara Evelyn (; 1873–1952) and the Rev. John Norman Maclean (1862–1941). Rev. Maclean homeschooled the young Norman and his brother Paul Davidson MacLean (1906–1938) until 1913. Norman Maclean also grew up with five sisters.


title: Norman Maclean

text: While Maclean was a child in Clarinda, he often witnessed his father working hard to learn diction and elocution and to rid his pronunciation of all signs that Canadian Gaelic, rather than Canadian English, was his first language. It was also in Clarinda that Rev. Maclean first developed a passion for the American sport of fly fishing, which had not previously been practiced by the minister or his forbears in the Inner Hebrides or in Nova Scotia. Rev. Maclean successfully passed on his love of fly fishing to both of his sons.


title: Norman Maclean

text: When asked by an interviewer about having been homeschooled by his father, Maclean recalled, "I think the most important thing is that he read aloud to us. He was a minister, and every morning after breakfast we had what was called family worship. We'd all sit with our breakfast chairs pulled back from the table and he would read to us from the Bible or from some religious poet. He was a very good reader... that was very good for me because in doing that, he would bring out the rhythms of the Bible. That reading instilled in me this great love of rhythm in language."


title: Norman Maclean

text: At the invitation of the elders of the Presbyterian church there, the Maclean family relocated to Missoula, Montana in 1909. The following years considerably influenced and inspired Norman's writings, appearing prominently in the short story "The Woods, Books, and Truant Officers" (1977) and the semi-autobiographical novella "A River Runs Through It and Other Stories" (1976).


title: Norman Maclean

text: Maclean was only 14 years old and was too young to enlist in the American Expeditionary Force during World War I, so he instead found work for the United States Forest Service in what is now the Bitterroot National Forest of northwestern Montana. The novella "USFS 1919: The Ranger, the Cook, and a Hole in the Sky" and the story "Black Ghost" in "Young Men and Fire" (1992) are semi-fictionalized accounts of these experiences.


title: Norman Maclean

text: Maclean later attended Dartmouth College, where he served as editor-in-chief of the humor magazine the "Dartmouth Jack-O-Lantern"; the editor-in-chief to follow him was Theodor Geisel, better known as Dr. Seuss and who, according to Maclean, was “the craziest guy I ever met.” He was also a member of the Sphinx and Beta Theta Pi.


title: Norman Maclean

text: During a 1986 interview, Maclean described the enormous gratitude he felt for having been able to attend creative writing classes taught at Dartmouth by the poet Robert Frost. Maclean stated that he learned an enormous amount from Frost, which he carried with him for the rest of his life. During the same interview, Maclean recalled that his lifelong admiration for and emulation of the writing style of Ernest Hemingway also began during his time at Dartmouth.


title: Norman Maclean

text: Maclean received his Bachelor of Arts in 1924 and chose to remain in Hanover, New Hampshire to serve as an instructor until 1926—a time he recalled in "This Quarter I Am Taking McKeon: A Few Remarks on the Art of Teaching".


title: Norman Maclean

text: Maclean's future wife, Jessie Burns (1905–1968), was born in Butte, Montana on January 24, 1905. Her father, John Burns, had been born at Marlborough, Massachusetts to Scots-Irish parents who had recently emigrated from a village near Belfast. Jesse's mother, Florence MacLeod, was a Scottish-Canadian immigrant to Montana. At the time of Jessie's birth, her father ran the general store in Wolf Creek, where she was raised, in between attending school in Butte.


title: Norman Maclean

text: Jessie Burns had red hair and freckles and was known in her childhood as a tomboy. She first met Norman Maclean during a December party in the Helena valley. They were returning home after the party with another couple in Jessie's car, when a blizzard descended and the car's radiator froze. MacLean tried pouring water in, only to have the water freeze as well. Maclean then started hiking through the blizzard to seek help, but soon found that the car had caught up with him, as the cold had prevented the engine from overheating. Norman felt foolish, but Jessie always considered him the hero of the blizzard.


title: Norman Maclean

text: Maclean and Burns married on September 24, 1931, and had two children: a daughter Jean (born in 1942), now a lawyer, and a son, John Norman Maclean (born in 1943).


title: Norman Maclean

text: Following their marriage, Jessie handled the family's finances and wrote all the checks. Norman also gave up typing and wrote almost everything, including his books, "in a cramped longhand that generations of typists at the University and elsewhere prided themselves on learning to decipher."


title: Norman Maclean

text: Their son, John Maclean, has since written that their family always led two lives. One life was during the summers at the log cabin built by Rev. Maclean near Seeley Lake, Montana. The other life took place in Chicago during the academic year. In fact, on July 26, 1950, the Maclean family was driving between Gillette and Sheridan, Wyoming when they heard over the radio about the outbreak of the Korean War. Stunned, Jessie Maclean said, "We're at war; it should feel different." Outside their family's car, however, "nothing moved but heat waves."


title: Norman Maclean

text: At the University of Chicago, Jessie Maclean's "open personality", made her a lot of friends. It was often said of her in later years, "She was the only one who'd talk to the young faculty wives."


title: Norman Maclean

text: During a 1986 interview, Maclean recalled, "I love Chicago. My wife was very wonderful in helping me come to feel that. I was very provincial in a lot of ways. She was gay and loved life wherever she lived. She really worked me over in our early years in Chicago. I was insolent and provincial about that city. She made me see how beautiful it was, made me see the geometric and industrial and architectural beauty."


title: Norman Maclean

text: The neurologist Dr. Sidney Schulman later said of Jessie Maclean's role at the university, "Jessie knew what was to be said. She said less than she knew, but what she said was enough, and she said it with humor, with literary allusions, and with simplicity. She came to be a sort of housemother. In being this, she was unaware of it - no self-satisfied awareness that what she was doing was noble. She was not playacting. It was part of her existence."


title: Norman Maclean

text: Their son, John Norman Maclean is now a journalist and author of "Fire on the Mountain: The True Story of the South Canyon Fire" (1999) and two other books, "Fire & Ashes" (2003) and "The Thirtymile Fire: A Chronicle of Bravery and Betrayal" (2007).


title: Norman Maclean

text: After similarly graduating from Dartmouth, Norman's younger brother, Paul Davidson MacLean, became well known as an investigative journalist, who fearlessly exposed political corruption in Helena, Montana linked to the powerful Anaconda Copper Mining Company. Paul Maclean later worked alongside his brother and sister-in-law at the University of Chicago during the Jazz Age and the Depression era. In addition to his talents for both writing and fly fishing, Paul Maclean suffered from alcoholism and gambling addiction, in addition to being a notorious brawler and a womanizer. According to Norman, all of these addictions and behaviors had a very long generational history and could be traced all the way back to the Maclean family's earliest origins among the Gaels of the Inner Hebrides of Scotland. Despite repeated attempts by his family to offer help, Paul MacLean rejected all such overtures.


title: Norman Maclean

text: On the early morning of May 2, 1937, Paul Maclean was attacked and brutally beaten at Sixty-Third Street and Drexel Avenue in Chicago by two men who removed all the money from Maclean's wallet and, according to an eyewitness, drove away afterwards in a car. Paul Maclean was taken to nearby Woodlawn Hospital, where he died, without regaining consciousness, at 1:20PM that same afternoon. According to his brother Norman Maclean and statements made to the press by Detective Sergeant Ignatius Sheehan, Paul Maclean fought back savagely against his assailants and sold his life very dearly. So much so, in fact, that nearly all the bones in his right hand were found by the medical examiner to have been broken during his last fight.


title: Norman Maclean

text: Following a homicide investigation led by Detective Sergeant Ignatius Sheehan, Chicago Police Department Captain Mark Boyle told the Cook County Coroner's Office that Paul Maclean's murder was a mugging gone bad, which remains the official explanation in police files. Another widely held theory at the time was that Paul Maclean's two murderers were linked to organized crime and the murder was over Maclean's inability or refusal to pay an illegal gambling or loansharking debt owed to the Chicago Outfit. No arrests were ever made, however, and the case remains officially unsolved.


title: Norman Maclean

text: Only Norman Maclean accompanied his brother's casket on an overnight train trip from Chicago to Montana. After the funeral, Maclean spent several weeks of compassionate leave with his parents at their family's cabin at Seeley Lake.


title: Norman Maclean

text: Rev. Maclean was understandingly very skeptical of the Chicago Police Department's official explanation for his son's murder. During the compassionate leave, he asked Norman, "Do you think it was just a stick-up and foolishly he tried to fight his way out? You know what I mean -- that it wasn't connected to anything in his past?" Norman replied that the Chicago Police Department didn't know and that neither did he.


title: Norman Maclean

text: Norman Maclean later wrote that their father aged rapidly following Paul's murder and that, "Like many Scottish ministers before him, he had to derive what comfort he could from the faith that his son had died fighting."


title: Norman Maclean

text: A few years later, Rev. Maclean brought up his older son's fondness for writing nonfiction and advised, "After you have finished your true stories sometime, why don't you make up a story and the people to go with it? Only then will you understand what happened and why. It is those we live with and love and should know who elude us."


title: Norman Maclean

text: During visits to the cabin at Seeley Lake in later years, journalist John Norman Maclean would often hear his father calling out over the lake in the evenings, "Paul! Paul!"


title: Norman Maclean

text: Maclean began graduate studies in English at the University of Chicago in 1928 and earned a PhD in 1940.


title: Norman Maclean

text: Like his contemporary C.S. Lewis, Maclean acquired a reputation for personal magnetism and for making the writings of difficult Medieval authors like François Rabelais and Geoffrey Chaucer come alive in the lecture hall. One of his students later said, "Norman F. Maclean is one of the best liked guys around this place. He is best remembered because when we were freshmen we used to come to class only when he lectured. His classes were always overrun."


title: Norman Maclean

text: According to another of his students, the poet Marie Borroff, Maclean was considered a unique figure at the university because he came from a "wilderness outpost", was a gifted marksman with a rifle, played a rough game of handball, and was every bit as much of an expert on George Armstrong Custer as he was on Aristotle.


title: Norman Maclean

text: During World War II, Maclean declined a commission in the Office of Naval Intelligence to serve as dean of students. During the war, he also served as director of the Institute on Military Studies and co-authored "Manual of Instruction in Military Maps and Aerial Photographs".


title: Norman Maclean

text: Maclean eventually became the William Rainey Harper Professor in the Department of English and taught the Romantic poets and Shakespeare. "Every year I said to myself, 'You better teach this bastard so you don't forget what great writing is like.' I taught him technically, two whole weeks for the first scene from "Hamlet". I'd spend the first day on just the line, 'Who's there?'"


title: Norman Maclean

text: U.S. Supreme Court Justice John Paul Stevens took a poetry class taught by Maclean at the University of Chicago and later called him, "the teacher to whom I am most indebted."


title: Norman Maclean

text: Maclean also wrote two scholarly articles, "From Action to Image: Theories of the Lyric in the Eighteenth Century" and "Episode, Scene, Speech, and Word: The Madness of Lear", the latter describing a theory of tragedy that he revisited in his later work.


title: Norman Maclean

text: After his retirement in 1973, Maclean began, as his children Jean and John had often encouraged him, to write down the stories he liked to tell.


title: Norman Maclean

text: As their father had urged before his death in 1941, Maclean wrote a slightly fictionalized account of his relationship with his brother Paul, beginning with their childhood in Missoula and particularly focusing on their last summer together with their parents before Paul's murder in 1937. The story was included with two other novellas in the collection "A River Runs Through It and Other Stories". Another story in the collection described Maclean's employment as a teenager by the United States Forest Service and was titled "USFS 1919: The Ranger, the Cook, and a Hole in the Sky". The third novella in the collection was "Logging and Pimping and 'Your pal, Jim"".


title: Norman Maclean

text: In a 1986 interview, Maclean expressed an intense hatred for mainstream New York City publishing companies, whom he accused of systematically cheating writers from Middle America. MacLean further recalled how his completed manuscript for "A River Runs Through It" was originally submitted to and rejected by Alfred A. Knopf.


title: Norman Maclean

text: In 1976, "A River Runs Through It and Other Stories" became the first work of fiction ever published by the University of Chicago Press. It was nominated by a selection committee to receive the Pulitzer Prize in Letters in 1977, but the full committee ignored the nomination and did not award a Pulitzer in that category for the year.


title: Norman Maclean

text: MacLean later recalled, "I had the good fortune of having a dream come true. I'm sure every rejected writer must dream of a time when he's written something that was rejected which turns out to be quite successful, so that all the publishers who rejected him are now coming around and kissing his ass at high noon, and he can tell them where to go."


title: Norman Maclean

text: Two or three years after being rejected by Alfred A. Knopf, Maclean received a letter from a senior New York City editor, asking whether Alfred A. Knopf, "could have the privilege of getting first crack", at Maclean's next book. MacLean wrote back, "If it should come to pass that the world comes to a place when Alfred A. Knopf is the only publishing company left and I am the only author, then that will be the end of the world of books."


title: Norman Maclean

text: Maclean spent the last years of his life attempting to write a creative non-fiction book about the 13 smokejumpers who lost their lives fighting the 1949 Mann Gulch Forest Fire. Maclean also collaborated with several others on adapting "A River Runs Through It" into a screenplay. He died in Chicago on August 2, 1990. At his own request, Maclean's body was cremated and his ashes were scattered over the mountains of Montana.


title: Norman Maclean

text: Maclean's manuscript on the Mann Gulch fire was published posthumously as "Young Men and Fire" and won the National Book Critics Circle Award in 1992.


title: Norman Maclean

text: In 1991, a renovated church retirement home was turned into an undergraduate dormitory on the University of Chicago campus named Maclean House. Maclean House's mascot was the "Stormin' Normans" in honor of its namesake. The dorm was closed after the 2015–2016 academic year, subsequently sold, and turned into apartments.


title: Norman Maclean

text: In 2008, the University of Chicago Press published a new compendium of unpublished and some previously published works, "The Norman Maclean Reader". The anthology included parts of a never-finished book about George Armstrong Custer and the Battle of the Little Bighorn which Maclean had worked on from 1959 to 1963. "Publishers Weekly" gave the book a respectful review in the summer of 2008, remarking, "Readers of the two earlier books will find, as Weltzien [Alan Weltzien, the book's editor] phrases it, 'new biographical insights into one of the most remarkable and unexpected careers in American letters.'"


title: Carlton Banks

text: Carlton Banks is a fictional character portrayed by Alfonso Ribeiro on the NBC television sitcom "The Fresh Prince of Bel-Air" from September 1990 to May 1996, the preppy and politically conservative cousin, main foil, and eventual close friend to Will Smith's cool and street-smart lead character. The character has been praised for portraying a complex and sympathetic foil with an arc of personal growth over the course of the show. The character is also known for a dance with humorously exaggerated movements developed for the character by Ribeiro, which came to be known as "The Carlton". Ribeiro also crossed over his role as Carlton into the "In the House" episode "Dog Catchers" before returning the following season as series regular Dr. Maxwell Stanton for the remainder of that series' run.


title: Carlton Banks

text: Carlton was "an affluent teenager attending private school in the ritzy Bel-Air sub-section of Los Angeles", who wore "button-down collared shirts and sweaters (often knotted around his neck)". He was "notoriously preppy", and a firmly conservative Republican. Writer Andy Borowitz described the character as an effort to portray "the anti-Will". The character was loosely based on the children of "Fresh Prince" executive producer Quincy Jones, and was named after Borowitz's classmate at Harvard University, Carlton Cuse. However, Carlton "had layers that prevented him from being a one-dimensional snob".


title: Carlton Banks

text: In the 2020 "Fresh Prince of Bel-Air Reunion", Smith noted that the show's comedy "was originally centered on the friction between Will and Uncle Phil... but it quickly become evident that the Will-Carlton dynamic would be the series' primary source of humor", and "the tension between Carlton and Will" therefore became "the tension at the heart of the show". Screenwriter Rob Edwards described how he sought to insure that Carlton would not be a "walking punch-line" like some sitcom antagonists, but would be a strong character, capable of effectively challenging the protagonist. Despite his faults, primarily arrogance, insecurity, and naïveté, Carlton is also shown as having a number of qualities that black viewers identified as positive even when they were held up to scorn—honesty, studiousness and dedication to education, and respect for his parents.


title: Carlton Banks

text: In earlier seasons, Carlton made frequent references to virginity (which was by choice), and also planned to attend Princeton (Philip's alma mater). In later seasons, these arcs were both resolved: Carlton did indeed lose his virginity, but was not initially admitted to Princeton. He instead first attended the (fictional) University of Los Angeles, where he briefly managed ULA's student store, the Peacock. However, in the 6th and last season, he finally gained transfer admission to Princeton, and leaves for the East Coast in the series finale. He often proved both friend and foe for Will. Carlton's role model is talk show host Bryant Gumbel and his favorite musician (and guardian angel) is Tom Jones. His favorite actor is William Shatner, whom he annoys by making lame Star Trek jokes. He idolizes Macaulay Culkin because he starred in a highly successful movie that earned millions, and because he is "one heck of a good actor!". In the episode "Hex and the Single Man", Carlton went trick-or-treating as Macaulay. In a later episode, it is revealed that Carlton has Santa Claus' fax number, which he has repeatedly used to request admission to Princeton. He is very similar to "Family Ties" character Alex P. Keaton in that he is a Republican, dresses in a preppy style, is obsessed with money, is short (Ribeiro is 5ft 6.25in, or 168cm), with his height a common butt of jokes by Will, and does not enjoy the popular music of most people his age. In some episodes, it is revealed that when he dances "other than the famous Carlton Dance" he dances very well.


title: Carlton Banks

text: Ribeiro, who had previously been in the cast of the 1980s show "Silver Spoons", auditioned wearing a track suit. Carlton was Ribeiro's breakout role, in which he "consistently stole scenes from Will Smith". Ribeiro said that Carlton was a character that he "had a blast playing for six years", but also noted that for many years thereafter, the role caused him to be "pigeon-holed as an actor based on that character".


title: Carlton Banks

text: Carlton Banks is played by Jelani Talib in the 2019 short film "Bel-Air", a reimagining of the original show as a modern drama. In September 2020, a two-season series based on the short film was picked up by the streaming service Peacock, with Will Smith as an executive producer commenting on his excitement to explore the characters in this format, specifically referencing "[t]he Carlton character, a Black young Republican, modern day? The heat that will be stirred up between these characters". Olly Sholotan was cast as Carlton in the actual reboot, described in one review as "not the same nerdy Alfonso Ribeiro with a token funny dance. He's almost cool—with toned biceps and a friend circle lacrosse players".


title: Carlton Banks

text: Born August 4, 1974, Carlton is the son of Vivian and Philip Banks, and Will's pedantic maternal cousin. A quintessential preppy, like many of his social class, Carlton aspires to attend an Ivy League university; in earlier seasons, he states he aims to get into Yale University, but later fixes a determined focus on Princeton University, his father Philip's alma mater.


title: Carlton Banks

text: Like his father Phillip, Carlton is a firmly conservative Republican and this often puts him at odds with Will. Although Carlton and Will often exchange insults, and Will normally refers to Carlton as a disgrace, Carlton obviously cares about Will, referring to him in the 2nd-season episode 'Vying for Attention' as "the brother I've always wanted". At first it appears there is an antagonistic relationship between Will and Carlton, but in later seasons Will significantly warms to Carlton, ultimately accepting Carlton and the other cousins as the siblings he never had. On one occasion in the season three episode "Just Say Yo", Carlton is considerate enough to cover for Will when he is admitted to the hospital after having taken speed tablets from inside Will's locker, but allows his parents to think that Will saved him. He attributes this to "still being high at the time" when asked by Will why he covered for him. This spurs Will to tearfully confess the truth to the family; although Carlton did ingest speed, Will bore responsibility as he had accepted the pills from a school friend, storing them in his locker, then absentmindedly said to Carlton he had a bottle of Vitamin E in his locker. Early on, Carlton is also seen to get extremely jealous almost anytime something great happens to Will. Examples would be when, in the Season One episode "Courting Disaster" Will joins the school basketball team with Carlton already on it. Will becomes the star of the team and Carlton becomes jealous and the competition between the two starts. Carlton decides to steal the ball from Will and take the game winning shot.


title: Carlton Banks

text: Carlton drives a silver Mercedes-Benz E-Class from the early 1990s, which is seen in a few episodes. Carlton also was a bit of a servant to sister Ashley when she hit it big on the singing charts. He held doors open for her and fanned Ashley while she tanned. He is also a big fan of "The Jeffersons" and "Beverly Hills, 90210", the latter of which he is confident enough to admit to others; this is unlike Will, who scoffs at the show in front of friends but confesses to Carlton that he is a secret "90210" fan as well.


title: Carlton Banks

text: Carlton is often called upon to do a comic, usually improvised dance routine to Tom Jones' "It's Not Unusual" (which was inspired by a dance performed by Courteney Cox in the music video for Bruce Springsteen's "Dancing in the Dark"). In earlier seasons, he makes frequent references to his virginity (twice referencing that he plans on losing it at some point), and also plans to attend Princeton University. In later seasons, these arcs are both resolved: Carlton does indeed lose his virginity to a woman who is married to the Dean of Princeton, but is not initially admitted to Princeton; instead he first attends the University of Los Angeles, where he briefly manages ULA's student store, the Peacock Stop.


title: Carlton Banks

text: Carlton makes no secret that he is desperate to lose his virginity. In the season 4 episode "It's Better to Have Loved and Lost It", that's what happens, with a lady, Joanne, with whom he has a one night stand with after an evening at the Tom Jones Museum. He proclaims he lives for her, but she gets back with her husband, who is the dean of Princeton University.


title: Carlton Banks

text: As seen in the episodes "You Bet Your Life" and "Viva Lost Wages", Carlton also seems to have a gambling problem and loses all of his money in any situation where gambling is involved and constantly imagines the gambling tables and slot machines talking to him, but seems fully aware that he is subject to compulsive gambling, and this limits his exposure to gaming. He usually declares that gambling is "evil" right before he goes all in and loses his and others' money. One exception to this was where he participated in a casino night in the season two episode "Something for Nothing", but that was done for charitable reasons and not for real money. In season five's "Bullets Over Bel-Air", Will tries to protect Carlton when they get robbed after using an automated teller machine, Will gets shot, taking a bullet for Carlton and is sent to the hospital (eventually recovering from his injuries); Carlton acquires a firearm later in the episode, as the event heightens his awareness of the need for self-defense, but later disposes of the handgun upon Will's insistence.


title: Carlton Banks

text: One running joke in the show involves Carlton repeatedly being slapped in the back of the head by various characters, usually in response to comments that are ridiculously self-centered (in later seasons, for example, he would often make humorous comments about gaining his father's inheritance) or due to portraying ignorance of lives other than his own. Often Will would ask to hold what Carlton is holding and once receiving it he would slap Carlton across the head with the object (e.g. a folder containing Will's testament written by Carlton, in "Ill Will"). Carlton's height is frequently made fun of, especially by Will, who, in the episode "Grumpy Young Men", jokes that Carlton is the average height for a woman.


title: Carlton Banks

text: He is sometimes portrayed as being extremely naïve. An example is when, in the episode "Mistaken Identity", he and Will are arrested after police officers falsely believe that they stole a Mercedes-Benz belonging to Philip's law firm partner, who requested Will and Carlton drive the vehicle to Palm Springs as a favor. At the end, Carlton insists that the policemen were only doing their job, not really accepting the fact that he and Will were victims of racial profiling. However, he seems to wonder if they were wrong, as when he asks his father if he (Phil) were a policeman if he would pull over someone who was driving too slow, for which Phil answers: "I asked myself the same thing the first time I was stopped"; after that, Carlton seems in deep thought over the situation. Although he was portrayed early on as a snobby rich kid, Carlton evolved after having his view challenged when arrested for "stealing a car" and when Will is shot, Carlton is angered that the shooter will probably not face justice for harming Will.


title: Carlton Banks

text: In the sixth and final season, Carlton finally gains transfer admission to Princeton University however, due to his fear of not living up to Philip's achievements, Carlton decides not to attend Princeton and briefly becomes interested in pursuing a career in bowling. However, he gets over his fear and leaves for the east coast in the series finale. In 2017, Ribeiro speculated that following the events of the series, Carlton would have tried to follow his father's career path, becoming a lawyer and eventually working towards becoming a judge.


title: Carlton Banks

text: The character of Carlton in the 2022 reboot series is more serious of a character, and is initially more hostile to Will. This hostility is exacerbated by Will's flirtation with Lisa, who happens to be his cousin Carlton's ex-girlfriend. Will catches Carlton sniffing Xanax and agrees to stay silent if Carlton helps get Uncle Phil and Aunt Viv to ease up on him. They pretend to make peace and go to a beach party. Will meets Lisa again and kisses her, and a jealous Carlton pushes Will into the pool. Will can't swim, so Lisa pulls him out, and he punches Carlton. Over the course of the season, Carlton warms to Will, who dissuades Carlton from further drug use.


title: Carlton Banks

text: Carlton in the original series was known for frequently dancing a specific set of steps to Tom Jones' "It's Not Unusual", a dance routine that gained fame as "The Carlton". Ribeiro developed the dance, later claiming to have drawn inspiration from the appearance by Courteney Cox in the 1984 music video for Bruce Springsteen's "Dancing in the Dark", and by Eddie Murphy depicting white people dancing in "Eddie Murphy Raw". On May 24, 2013, Ribeiro made a cameo appearance on "The Graham Norton Show" to perform "The Carlton", with show guests Will and Jaden Smith. Ribeiro incorporated the dance into his performance for week four of season 19 of "Dancing With the Stars", earning the only perfect 10 of the episode, along the way to winning the season.


title: Carlton Banks

text: In December 2018, NBC and CBS reported that Ribeiro, along with Instagram star Russell Horning, aka Backpack Kid, and rapper Terrence Ferguson, aka 2 Milly, brought a lawsuit against Epic Games for their decision to feature respective choreographies in the popular game "Fortnite". "The Carlton" was one of the many dances that "Fortnite" players can purchase for their avatars. Epic Games declined to comment on the lawsuits. The U.S. Copyright Office denied him a copyright for his dance in January 2019. The Copyright Office described the contested work as "a simple routine made up of three dance steps, the first of which is popularly known as 'The Carlton'", describing the steps for the entire routine as follows:


title: MESSENGER

text: MESSENGER was a NASA robotic space probe that orbited the planet Mercury between 2011 and 2015, studying Mercury's chemical composition, geology, and magnetic field. The name is a backronym for "Mercury Surface, Space Environment, Geochemistry, and Ranging", and a reference to the messenger god Mercury from Roman mythology.


title: MESSENGER

text: "MESSENGER" was launched aboard a Delta II rocket in August 2004. Its path involved a complex series of flybys – the spacecraft flew by Earth once, Venus twice, and Mercury itself three times, allowing it to decelerate relative to Mercury using minimal fuel. During its first flyby of Mercury in January 2008, "MESSENGER" became the second mission, after Mariner 10 in 1975, to reach Mercury.


title: MESSENGER

text: "MESSENGER" entered orbit around Mercury on March 18, 2011, becoming the first spacecraft to do so. It successfully completed its primary mission in 2012. Following two mission extensions, the spacecraft used the last of its maneuvering propellant to deorbit, impacting the surface of Mercury on April 30, 2015.


title: MESSENGER

text: "MESSENGER"'s formal data collection mission began on April 4, 2011. The primary mission was completed on March 17, 2012, having collected close to 100,000 images. "MESSENGER" achieved 100% mapping of Mercury on March 6, 2013, and completed its first year-long extended mission on March 17, 2013. "MESSENGER"s second extended mission lasted for over two years, but as its low orbit degraded, it required reboosts to avoid impact. It conducted its final reboost burns on October 24, 2014, and January 21, 2015, before crashing into Mercury on April 30, 2015.


title: MESSENGER

text: During its stay in Mercury orbit, "MESSENGER"<nowiki>'</nowiki>s instruments yielded significant data, including a characterization of Mercury's magnetic field and the discovery of water ice at the planet's north pole, which had long been suspected on the basis of Earth-based radar data.


title: MESSENGER

text: In 1973, Mariner 10 was launched by NASA to make multiple flyby encounters of Venus and Mercury. Mariner 10 provided the first detailed data of Mercury, mapping 40–45% of the surface. Mariner 10's final flyby of Mercury occurred on March 16, 1975. No subsequent close-range observations of the planet would take place for more than 30 years.


title: MESSENGER

text: In 1998, a study detailed a proposed mission to send an orbiting spacecraft to Mercury, as the planet was at that point the least-explored of the inner planets. In the years following the Mariner 10 mission, subsequent mission proposals to revisit Mercury had appeared too costly, requiring large quantities of propellant and a heavy lift launch vehicle. Moreover, inserting a spacecraft into orbit around Mercury is difficult, because a probe approaching on a direct path from Earth would be accelerated by the Sun's gravity and pass Mercury far too quickly to orbit it. However, using a trajectory designed by Chen-wan Yen in 1985, the study showed it was possible to seek a Discovery-class mission by using multiple, consecutive gravity assist, 'swingby' maneuvers around Venus and Mercury, in combination with minor propulsive trajectory corrections, to gradually slow the spacecraft and thereby minimize propellant needs.


title: MESSENGER

text: The "MESSENGER" mission was designed to study the characteristics and environment of Mercury from orbit. Specifically, the scientific objectives of the mission were:


title: MESSENGER

text: The "MESSENGER" spacecraft was designed and built at the Johns Hopkins University Applied Physics Laboratory. Science operations were managed by Sean Solomon as principal investigator, and mission operations were also conducted at JHU/APL. The "MESSENGER" bus measured tall, wide, and deep. The bus was primarily constructed with four graphite fiber / cyanate ester composite panels that supported the propellant tanks, the large velocity adjust (LVA) thruster, attitude monitors and correction thrusters, the antennas, the instrument pallet, and a large ceramic-cloth sunshade, measuring tall and wide, for passive thermal control. At launch, the spacecraft weighed approximately with its full load of propellant. "MESSENGER"<nowiki>'</nowiki>s total mission cost, including the cost of the spacecraft's construction, was estimated at under US$450 million.


title: MESSENGER

text: Main propulsion was provided by the 645 N, 317 sec. I bipropellant (hydrazine and nitrogen tetroxide) large velocity assist (LVA) thruster. The model used was the LEROS 1b, developed and manufactured at AMPAC‐ISP's Westcott works, in the United Kingdom. The spacecraft was designed to carry of propellant and helium pressurizer for the LVA.


title: MESSENGER

text: Four monopropellant thrusters provided spacecraft steering during main thruster burns, and twelve monopropellant thrusters were used for attitude control. For precision attitude control, a reaction wheel attitude control system was also included. Information for attitude control was provided by star trackers, an inertial measurement unit and six sun sensors.


title: MESSENGER

text: The probe included two small deep space transponders for communications with the Deep Space Network and three kinds of antennas: a high gain phased array whose main beam could be electronically steered in one plane, a medium-gain "fan-beam" antenna and a low gain horn with a broad pattern. The high gain antenna was used as transmit-only at 8.4 GHz, the medium-gain and low gain antennas transmit at 8.4 GHz and receive at 7.2 GHz, and all three antennas operate with right-hand circularly polarized (RHCP) radiation. One of each of these antennas was mounted on the front of the probe facing the Sun, and one of each was mounted to the back of the probe facing away from the Sun.


title: MESSENGER

text: The space probe was powered by a two-panel gallium arsenide/germanium solar array providing an average of 450 watts while in Mercury orbit. Each panel was rotatable and included optical solar reflectors to balance the temperature of the array. Power was stored in a common-pressure-vessel, 23-ampere-hour nickel–hydrogen battery, with 11 vessels and two cells per vessel.


title: MESSENGER

text: The spacecraft's onboard computer system was contained in an Integrated Electronics Module (IEM), a device that combined core avionics into a single box. The computer featured two radiation-hardened IBM RAD6000s, a 25 megahertz main processor, and a 10 MHz fault protection processor. For redundancy, the spacecraft carried a pair of identical IEMs. For data storage, the spacecraft carried two solid-state recorders able to store up to one gigabyte each. The IBM RAD6000 main processor collected, compressed, and stored data from "MESSENGER"<nowiki>'</nowiki>s instruments for later playback to Earth.


title: MESSENGER

text: "MESSENGER" used a software suite called SciBox to simulate its orbit and instruments, in order to "choreograph the complicated process of maximizing the scientific return from the mission and minimizing conflicts between instrument observations, while at the same time meeting all spacecraft constraints on pointing, data downlink rates, and onboard data storage capacity."


title: MESSENGER

text: Included two CCD cameras, a narrow-angle camera (NAC) and a wide-angle camera (WAC) mounted to a pivoting platform. The camera system provided a complete map of the surface of Mercury at a resolution of 250 meters/pixel, and images of regions of geologic interest at 20–50 meters/pixel. Color imaging was possible only with the narrow-band filter wheel attached to the wide-angle camera.


title: MESSENGER

text: Measured gamma-ray emissions from the surface of Mercury to determine the planet's composition by detecting certain elements (oxygen, silicon, sulfur, iron, hydrogen, potassium, thorium, uranium) to a depth of 10 cm.


title: MESSENGER

text: Determined the hydrogen mineral composition to a depth of 40 cm by detecting low-energy neutrons resulting from the collision of cosmic rays with the minerals.


title: MESSENGER

text: Mapped mineral composition within the top millimeter of the surface on Mercury by detecting X-ray spectral lines from magnesium, aluminum, sulphur, calcium, titanium, and iron, in the 1–10 keV range.


title: MESSENGER

text: Measured the magnetic field around Mercury in detail to determine the strength and average position of the field.


title: MESSENGER

text: Provided detailed information regarding the height of landforms on the surface of Mercury by detecting the light of an infrared laser as the light bounced off the surface.


title: MESSENGER

text: Determined the characteristics of the tenuous atmosphere surrounding Mercury by measuring ultraviolet light emissions, and ascertained the prevalence of iron and titanium minerals on the surface by measuring the reflectance of infrared light.


title: MESSENGER

text: Measured the charged particles in the magnetosphere around Mercury using an energetic particle spectrometer (EPS) and the charged particles that come from the surface using a fast imaging plasma spectrometer (FIPS).


title: MESSENGER

text: Measured the gravity of Mercury and the state of the planetary core by utilizing the spacecraft's positioning data.


title: MESSENGER

text: The "MESSENGER" probe was launched on August 3, 2004, at 06:15:56 UTC by NASA from Space Launch Complex 17B at the Cape Canaveral Air Force Station in Florida, aboard a Delta II 7925 launch vehicle. The complete burn sequence lasted 57 minutes bringing the spacecraft into a heliocentric orbit, with a final velocity of 10.68 km/s (6.64 miles/s) and sending the probe into a 7.9 billion-kilometer trajectory that took 6 years, 7 months and 16 days before its orbital insertion on March 18, 2011.


title: MESSENGER

text: Traveling to Mercury and entering orbit requires an extremely large velocity change ("see delta-v") because Mercury's orbit is deep in the Sun's gravity well. On a direct course from Earth to Mercury, a spacecraft is constantly accelerated as it falls toward the Sun, and will arrive at Mercury with a velocity too high to achieve orbit without excessive use of fuel. For planets with an atmosphere, such as Venus and Mars, spacecraft can minimize their fuel consumption upon arrival by using friction with the atmosphere to enter orbit (aerocapture), or can briefly fire their rocket engines to enter into orbit followed by a reduction of the orbit by aerobraking. However, the tenuous atmosphere of Mercury is far too thin for these maneuvers. Instead, "MESSENGER" extensively used gravity assist maneuvers at Earth, Venus, and Mercury to reduce the speed relative to Mercury, then used its large rocket engine to enter into an elliptical orbit around the planet. The multi-flyby process greatly reduced the amount of propellant necessary to slow the spacecraft, but at the cost of prolonging the trip by many years and to a total distance of 7.9 billion kilometers (4.9 billion miles).


title: MESSENGER

text: Several planned thruster firings en route to Mercury were unnecessary, because these fine course adjustments were performed using solar radiation pressure acting on MESSENGER's solar panels. To further minimize the amount of necessary propellant, the spacecraft orbital insertion targeted a highly elliptical orbit around Mercury.


title: MESSENGER

text: The elongated orbit had two other benefits: It allowed the spacecraft time to cool after the times it was between the hot surface of Mercury and the Sun, and also it allowed the spacecraft to measure the effects of solar wind and the magnetic fields of the planet at various distances while still allowing close-up measurements and photographs of the surface and exosphere.


title: MESSENGER

text: The spacecraft was originally scheduled to launch during a 12-day window that beginning May 11, 2004. On March 26, 2004, NASA announced the launch would be moved to a later, 15-day launch window beginning July 30, 2004, to allow for further testing of the spacecraft. This change significantly altered the trajectory of the mission and delayed the arrival at Mercury by two years. The original plan called for three fly-by maneuvers past Venus, with Mercury orbit insertion scheduled for 2009. The trajectory was changed to include one Earth flyby, two Venus flybys, and three Mercury flybys before orbit insertion on March 18, 2011.


title: MESSENGER

text: "MESSENGER" performed an Earth flyby one year after launch, on August 2, 2005, with the closest approach at 19:13 UTC at an altitude of 2,347 kilometers (1,458 statute miles) over central Mongolia. On December 12, 2005, a 524-second-long burn (Deep-Space Maneuver or DSM-1) of the large thruster adjusted the trajectory for the upcoming Venus flyby by 316 m/s.


title: MESSENGER

text: During the Earth flyby, the "MESSENGER" team imaged the Earth and Moon using MDIS and checked the status of several other instruments observing the atmospheric and surface compositions and testing the magnetosphere and determining that all instruments tested were working as expected. This calibration period was intended to ensure accurate interpretation of data when the spacecraft entered orbit around Mercury. Ensuring that the instruments functioned correctly at such an early stage in the mission allowed opportunity for multiple minor errors to be dealt with.


title: MESSENGER

text: The Earth flyby was used to investigate the flyby anomaly, where some spacecraft have been observed to have trajectories that differ slightly from those predicted. However no anomaly was observed in MESSENGER's flyby.


title: MESSENGER

text: On October 24, 2006, at 08:34 UTC, "MESSENGER" encountered Venus at an altitude of . During the encounter, "MESSENGER" passed behind Venus and entered superior conjunction, a period when Earth was on the exact opposite side of the Solar System, with the Sun inhibiting radio contact. For this reason, no scientific observations were conducted during the flyby. Communication with the spacecraft was reestablished in late November and performed a deep space maneuver on December 12, to correct the trajectory to encounter Venus in a second flyby.


title: MESSENGER

text: On June 5, 2007, at 23:08 UTC, "MESSENGER" performed a second flyby of Venus at an altitude of , for the greatest velocity reduction of the mission. During the encounter, all instruments were used to observe Venus and prepare for the following Mercury encounters. The encounter provided visible and near-infrared imaging data of the upper atmosphere of Venus. Ultraviolet and X-ray spectrometry of the upper atmosphere were also recorded, to characterize the composition. The ESA's Venus Express was also orbiting during the encounter, providing the first opportunity for simultaneous measurement of particle-and-field characteristics of the planet.


title: MESSENGER

text: "MESSENGER" made a flyby of Mercury on January 14, 2008 (making its closest approach of 200 km above the surface of Mercury at 19:04:39 UTC), followed by a second flyby on October 6, 2008. "MESSENGER" executed a final flyby on September 29, 2009, further slowing down the spacecraft. Sometime during the closest approach of the last flyby, the spacecraft entered safe mode. Although this had no effect on the trajectory necessary for later orbit insertion, it resulted in the loss of science data and images that were planned for the outbound leg of the fly-by. The spacecraft had fully recovered by about seven hours later. One last deep space maneuver, DSM-5, was executed on November 24, 2009, at 22:45 UTC to provide the required 0.177 km/s velocity change for the scheduled Mercury orbit insertion on March 18, 2011, marking the beginning of the orbital mission.


title: MESSENGER

text: The thruster maneuver to insert the probe into Mercury's orbit began at 00:45 UTC on March 18, 2011. The 0.9 km/s (0.5 mi./sec.) braking maneuver lasted about 15 minutes, with confirmation that the craft was in Mercury orbit received at 01:10 UTC on March 18 (9:10 PM, March 17 EDT). Mission lead engineer Eric Finnegan indicated that the spacecraft had achieved a near-perfect orbit.


title: MESSENGER

text: "MESSENGER"'s orbit was highly elliptical, taking it within of Mercury's surface and then away from it every twelve hours. This orbit was chosen to shield the probe from the heat radiated by Mercury's hot surface. Only a small portion of each orbit was at a low altitude, where the spacecraft was subjected to radiative heating from the hot side of the planet.


title: MESSENGER

text: After "MESSENGER"'s orbital insertion, an eighteen-day commissioning phase took place. The supervising personnel switched on and tested the craft's science instruments to ensure they had completed the journey without damage. The commissioning phase "demonstrated that the spacecraft and payload [were] all operating nominally, notwithstanding Mercury's challenging environment."


title: MESSENGER

text: The primary mission began as planned on April 4, 2011, with "MESSENGER" orbiting Mercury once every twelve hours for an intended duration of twelve Earth months, the equivalent of two solar days on Mercury. Principal Investigator Sean Solomon, then of the Carnegie Institution of Washington, said: "With the beginning today of the primary science phase of the mission, we will be making nearly continuous observations that will allow us to gain the first global perspective on the innermost planet. Moreover, as solar activity steadily increases, we will have a front-row seat on the most dynamic magnetosphere–atmosphere system in the Solar System."


title: MESSENGER

text: On October 5, 2011, the scientific results obtained by "MESSENGER" during its first six terrestrial months in Mercury's orbit were presented in a series of papers at the European Planetary Science Congress in Nantes, France. Among the discoveries presented were the unexpectedly high concentrations of magnesium and calcium found on Mercury's nightside, and the fact that Mercury's magnetic field is offset far to the north of the planet's center.


title: MESSENGER

text: In November 2011, NASA announced that the "MESSENGER" mission would be extended by one year, allowing the spacecraft to observe the 2012 solar maximum. Its extended mission began on March 17, 2012, and continued until March 17, 2013. Between April 16 and 20, 2012, "MESSENGER" carried out a series of thruster manoeuvres, placing it in an eight-hour orbit to conduct further scans of Mercury.


title: MESSENGER

text: In November 2012, NASA reported that "MESSENGER" had discovered both water ice and organic compounds in permanently shadowed craters in Mercury's north pole. In February 2013, NASA published the most detailed and accurate 3D map of Mercury to date, assembled from thousands of images taken by "MESSENGER". "MESSENGER" completed its first extended mission on March 17, 2013, and its second lasted until April 2015. In November 2013, "MESSENGER" was among the numerous space assets that imaged Comet Encke (2P/Encke) and Comet ISON (C/2012 S1). As its orbit began to decay in early 2015, "MESSENGER" was able to take highly detailed close-up photographs of ice-filled craters and other landforms at Mercury's north pole. After the mission was completed, review of the radio ranging data provided the first measurement of the rate of mass loss from the Sun.


title: MESSENGER

text: On July 3, 2008, the "MESSENGER" team announced that the probe had discovered large amounts of water present in Mercury's exosphere, which was an unexpected finding. In the later years of its mission, "MESSENGER" also provided visual evidence of past volcanic activity on the surface of Mercury, as well as evidence for a liquid iron planetary core. The probe also constructed the most detailed and accurate maps of Mercury to date, and furthermore discovered carbon-containing organic compounds and water ice inside permanently shadowed craters near the north pole.


title: MESSENGER

text: On February 18, 2011, a portrait of the Solar System was published on the "MESSENGER" website. The mosaic contained 34 images, acquired by the MDIS instrument during November 2010. All the planets were visible with the exception of Uranus and Neptune, due to their vast distances from the Sun. The "MESSENGER" "family portrait" was intended to be complementary to the Voyager family portrait, which was acquired from the outer Solar System by "Voyager 1" on February 14, 1990.


title: MESSENGER

text: After running out of propellant for course adjustments, "MESSENGER" entered its expected terminal phase of orbital decay in late 2014. The spacecraft's operation was extended by several weeks by exploiting its remaining supply of helium gas, which was used to pressurize its propellant tanks, as reaction mass. "MESSENGER" continued studying Mercury during its decay period. The spacecraft crashed onto the surface of Mercury on April 30, 2015, at 3:26 p.m. EDT (19:26 GMT), at a velocity of , probably creating a crater in the planet's surface approximately wide. The spacecraft was estimated to have impacted at 54.4° N, 149.9° W on Suisei Planitia, near the crater Janáček. The crash occurred at a place not visible from Earth at the time, and thus was not detected by any observers or instruments. NASA confirmed the end of the "MESSENGER" mission at 3:40 p.m. EDT (19:40 GMT) after NASA's Deep Space Network did not detect the spacecraft's reemergence from behind Mercury.


title: Residue (complex analysis)

text: In mathematics, more specifically complex analysis, the residue is a complex number proportional to the contour integral of a meromorphic function along a path enclosing one of its singularities. (More generally, residues can be calculated for any function formula_1 that is holomorphic except at the discrete points {"a"}, even if some of them are essential singularities.) Residues can be computed quite easily and, once known, allow the determination of general contour integrals via the residue theorem.


title: Residue (complex analysis)

text: The residue of a meromorphic function formula_2 at an isolated singularity formula_3, often denoted formula_4, formula_5, formula_6 or formula_7, is the unique value formula_8 such that formula_9 has an analytic antiderivative in a punctured disk formula_10.


title: Residue (complex analysis)

text: Alternatively, residues can be calculated by finding Laurent series expansions, and one can define the residue as the coefficient "a" of a Laurent series.


title: Residue (complex analysis)

text: The definition of a residue can be generalized to arbitrary Riemann surfaces. Suppose formula_11 is a 1-form on a Riemann surface. Let formula_11 be meromorphic at some point formula_13, so that we may write formula_11 in local coordinates as formula_15. Then, the residue of formula_11 at formula_13 is defined to be the residue of formula_18 at the point corresponding to formula_13.


title: Residue (complex analysis)

text: makes most residue computations easy to do. Since path integral computations are homotopy invariant, we will let formula_21 be the circle with radius formula_22. Then, using the change of coordinates formula_23 we find that


title: Residue (complex analysis)

text: Let us evaluate this integral using a standard convergence result about integration by series. We can substitute the Taylor series for formula_27 into the integrand. The integral then becomes


title: Residue (complex analysis)

text: Since the series converges uniformly on the support of the integration path, we are allowed to exchange integration and summation.


title: Residue (complex analysis)

text: The series of the path integrals then collapses to a much simpler form because of the previous computation. So now the integral around "C" of every other term not in the form "cz" is zero, and the integral is reduced to


title: Residue (complex analysis)

text: Suppose a punctured disk "D" = {"z" : 0 < |"z" − "c"| < "R"} in the complex plane is given and "f" is a holomorphic function defined (at least) on "D". The residue Res("f", "c") of "f" at "c" is the coefficient "a" of in the Laurent series expansion of "f" around "c". Various methods exist for calculating this value, and the choice of which method to use depends on the function in question, and on the nature of the singularity.


title: Residue (complex analysis)

text: where "γ" traces out a circle around "c" in a counterclockwise manner. We may choose the path "γ" to be a circle of radius "ε" around "c", where "ε" is as small as we desire. This may be used for calculation in cases where the integral can be calculated directly, but it is usually the case that residues are used to simplify calculation of integrals, and not the other way around.


title: Residue (complex analysis)

text: If the function "f" can be continued to a holomorphic function on the whole disk formula_33, then Res("f", "c") = 0. The converse is not generally true.


title: Residue (complex analysis)

text: If that limit does not exist, there is an essential singularity there. If it is 0 then it is either analytic there or there is a removable singularity. If it is equal to infinity then the order is higher than 1.


title: Residue (complex analysis)

text: It may be that the function "f" can be expressed as a quotient of two functions, formula_35, where "g" and "h" are holomorphic functions in a neighbourhood of "c", with "h"("c") = 0 and "h"'("c") ≠ 0. In such a case, L'Hôpital's rule can be used to simplify the above formula to:


title: Residue (complex analysis)

text: More generally, if "c" is a pole of order "n", then the residue of "f" around "z" = "c" can be found by the formula:


title: Residue (complex analysis)

text: This formula can be very useful in determining the residues for low-order poles. For higher-order poles, the calculations can become unmanageable, and series expansion is usually easier. For essential singularities, no such simple formula exists, and residues must usually be taken directly from series expansions.


title: Residue (complex analysis)

text: For holomorphic functions the sum of the residues at the isolated singularities plus the residue at infinity is zero.


title: Residue (complex analysis)

text: If parts or all of a function can be expanded into a Taylor series or Laurent series, which may be possible if the parts or the whole of the function has a standard series expansion, then calculating the residue is significantly simpler than by other methods.


title: Residue (complex analysis)

text: The first term contributes 1 to the residue, and the second term contributes 2 since it is asymptotic to formula_44.


title: Residue (complex analysis)

text: Note that, with the corresponding stronger symmetric assumptions on formula_45 and formula_46, it also follows


title: Crepitus

text: Crepitus is grating, crackling or popping sounds and sensations experienced under the skin and joints or a crackling sensation due to the presence of air in the subcutaneous tissue.


title: Crepitus

text: The sound can be created when two rough surfaces in an organism's body come into contact—for example, in osteoarthritis or rheumatoid arthritis when the cartilage around joints erodes and the surfaces in the joint grind against one another, or when the two fractured surfaces of the broken bones rub together. Crepitus is a common sign of bone fracture.


title: Crepitus

text: Crepitus can easily be created and observed by exerting a small amount of force on a joint, thus 'cracking it'. This is caused by bubbles of nitrogen forming in the synovial fluid bursting. Almost every joint in the body can be 'cracked' in this way, but the joints which require the least amount of effort include the hallux, knuckles and neck joints.


title: Crepitus

text: In soft tissues, crepitus can be produced when gas is introduced into an area where it is normally not present.