By Elizabeth Landau, CNN
The universe was just a kid at 4 billion years old. Thursday, scientists said that they have a measurement for all of the light that was around at that time that’s still traveling to us.
It’s called the extragalactic background light. This includes light from stars that existed when the universe was even younger than 4 billion years old. Researchers report in the journal Science that this can help with understanding how stars formed and how galaxies evolved.
“I think it’s amazing to be able to probe our universe when it was so young, when the very first stars formed," said Marco Ajello, researcher at Stanford University and study co-author.
Researchers write in the study that there have been several attempts in the past to detect this phenomenon, but none were successful.
The finding is important for estimating the number of smaller, fainter galaxies that current telescopes cannot detect, said Claude-Andre Faucher-Giguere, researcher in the Department of Astronomy at the University of California, Berkeley, who was not involved in the study.
Here’s why: Every telescope has limitations, especially its size. So astronomers can use them to detect the big, luminous galaxies, but there are more galaxies that the tools will miss.
“Studying the extragalactic background light allows us to overcome this limitation, because the background light is the sum of the light produced by all galaxies, including the ones that are too faint to be detected individually by traditional methods,” he said.
How they did it
To study this, scientists focused their efforts at high-energy gamma rays using NASA's Fermi Gamma-ray Space Telescope. Specifically, they looked at “blazars,” which are galactic nuclei that spew jets associated with supermassive black holes.
When this extragalactic background light absorbs gamma rays, the process produces electron-positron pairs. A positron is an anti-matter particle.
This is the inverse reaction from what’s described in Dan Brown’s novel “Angels and Demons,” explains Faucher-Giguere. In that book, the villains’ bomb would harness the extraordinary energy from matter and anti-matter annihilating each other.
Based on how many gamma rays are expected to be present, compared to how many were observed, scientists calculated the number of gamma rays that appeared to be absorbed by the starlight from the early universe.
In that sense, these gamma-ray sources are like “lighthouses” and the starlight is like the fog, Ajello said. Scientists know that starlight is absorbing the gamma rays when the "lighthouse" is dimmer.
Scientists can therefore add up the light from the galaxies they can detect, and compare that to the extragalactic background light. This subtraction is a clue to how many galaxies we haven’t yet directly detected with our telescopes, and how luminous they are, Faucher-Giguere said.
According to this study, the galaxies observed directly via telescope accounts for most of the extragalactic background light measured. That means there cannot be much more light coming from fainter galaxies, Faucher-Giguere explains. This also puts limits on how many black holes and massive stars were in the early universe.
“This is a new and unique constraint that all future models of galaxy and black hole evolution will have to satisfy,” Faucher-Giguere said.
An extremely powerful telescope is required to support and complement these findings by directly observing the first galaxies. NASA's James Webb Space Telescope, whose launch is scheduled for 2018, may do the trick.
"The Webb telescope will open a completely new era," Ajello said at a NASA press briefing Thursday.
Editor's note: Brian Williams is a space enthusiast and writer living in Salinas, California.
Back in 2008, something went bump in the night around Fomalhaut, a star in the constellation Piscis Austrinusa, 25 light-years away from Earth. Originally found by the Hubble Space Telescope, Fomalhaut b was announced as the first exoplanet (a planet outside our solar system) found through direct imaging in visible light, instead of by the usual planet-finding methods.
Moving through a dusty oblong ring surrounding its star, Fomalhaut b was thought to be a planet as much as three times Jupiter’s mass, carving a path through the ring.
Editor's note: Brian Williams is a space enthusiast and writer living in Salinas, California.
NASA’s Nuclear Spectroscopic Telescope Array, called NuSTAR, has taken its first glimpse of our galaxy’s supermassive black hole, thanks to a recent flare-up at the galactic core.
NuSTAR, a state-of-the-art, space-based X-ray telescope, was aimed at Sagittarius A*, a compact radio source identified as a black hole, for two days in July. The goal was to better understand just what makes our galaxy's central black hole so different from others.
Compared to other galaxies, the Milky Way’s black hole is relatively calm. While other supermassive black holes devour gas and stars around them, releasing large amounts of energy in the process, ours only seems to have the occasional light snack, showing just a bit of activity as matter is consumed: the tell-tale burst of energy seen in X-ray and radio emissions.
According to Fiona Harrison, NuSTAR’s principal investigator at CalTech in Pasadena, California, fortuitous timing plays no small role in observing the activity.
“We got lucky to have captured an outburst from the black hole during our observing campaign. These data will help us better understand the gentle giant at the heart of our galaxy and why it sometimes flares up for a few hours and then returns to slumber," she said in a written statement.
Thanks to the instruments aboard NuSTAR, the team was able to see the X-rays created by matter being heated up to approximately 180 million degrees Fahrenheit (or 100 million degrees Celsius) in regions where particles are accelerated close to the speed of light.
"Astronomers have long speculated that the black hole's snacking should produce copious hard X-rays, but NuSTAR is the first telescope with sufficient sensitivity to actually detect them," team member Chuck Hailey of Columbia University said in a written statement.
Fred Baganoff, a NuStar team leader at the Massachusetts Institute of Technology, stressed in an e-mail the importance of the NuSTAR data for getting a clearer picture of the dark heart of our galaxy.
“Understanding such a complex and alien environment from so far away is like piecing together a jigsaw puzzle when you do not know what the final image should look like; most of the pieces are missing and the whole puzzle is too small and far away to be seen by the human eye. What NuSTAR has done is give us more of the pieces. Until 2000, the only pieces we had were on the left-hand side of the puzzle in the radio and millimeter wave bands, where Sagittarius A* had been studied since its discovery in 1974. The entire right-hand side of the puzzle, visible only in the soft X-rays, hard X-rays and gamma-rays, was completely missing. ... The center of the puzzle was missing, too, since vast clouds of gas and dust completely block our view of the center of our galaxy in optical and ultraviolet light. Only one in a trillion optical photons makes it through that dark haze.”
Taken with data from other observatories (NASA’s Chandra X-ray Observatory and the W.M. Keck Observatory in Hawaii were also pointed at Sagittarius A*), scientists hope NuSTAR can shed light on the activity cycles and evolution of black holes. There is also a wealth of non-black hole related data that the X-ray space telescope will help scientists understand, Harrison said.
“NuSTAR will look at a wide range of phenomena from exploding stars to neutron stars and black holes. NuSTAR will even study our own sun!”
Four months into its two-year mission, NuSTAR is off to a promising start. Launched in June 2012, NuSTAR’s mission is to conduct a survey of black holes throughout the universe that are millions of times more massive than our own sun. As for what's next for NuStar, Harrison said it is working on other targets.
“NuSTAR has already moved on to look at the evolving remnant of a supernova explosion that happened in 1987 nearby, in the Large Magellanic Cloud (a satellite of the Milky Way) called SN1987A. NuSTAR will next look at very luminous objects in nearby galaxies, called ultraluminous X-ray sources. The source of their X-ray brilliance is not understood. NuSTAR looks at a new target every few days.”
About 160 new species have been discovered on a mountain in Borneo, researchers reported Thursday.
Fungi and spiders dominate the new species on Mount Kinabalu, the Malaysian and Dutch researchers said, but there are also new beetles and snails on the creature list and ferns on the plant list.
A frog the researchers found may also prove to be new once DNA testing is done, they said.
"While the detailed scientific work will take years, we already know that many of these species are new to science," researcher József Geml said in a press release.
The research was conducted by Sabah Parks, a Malaysian conservation organization, and Naturalis Biodiversity Center in the Netherlands.
They went to the mountain to collect DNA samples and try to determine whether species there evolved recently or long ago on the Malaysian peak.
At 13,435 feet, Kinabalu is the largest mountain in the Malay archipelago. It is a Malaysian national park and a UNESCO World Heritage Site.
All told, about 3,500 DNA samples were collected from more than 1,400 species. Researchers plan a publication on how evolution works in Borneo by the middle of next year.
Scientists think that water and organic molecules come together in the coldest places in space to begin the chemical reactions necessary for organics to evolve into prebiotic molecules – molecules that are precursors of life. Ice and organics could have hitched a ride to Earth on comets and asteroids, where they could have formed the building blocks of life as we know it.
Researchers at NASA’s Jet Propulsion Laboratory in Pasadena, California, are trying to better understand that process, and how life may have formed on Earth, by firing lasers at icy carbon-laden molecules in a lab.
Principal scientist Murthy Gudipati explained to CNN by e-mail: "In the cycle of formation, evolution, and death of stars, two key components of life (as we know of it): water and organic matter, evolve intimately with the third component energy (radiation) at every stage of this cycle – even at the coldest regions of the universe."
We all know the drill: Slip up on your regular brush-and-floss routine, and you may end up at the dentist's office with a cavity that needs to be filled. But what people did about their toothaches thousands of years ago?
Scientists in Italy have discovered what may be the earliest evidence of therapeutic dentistry performed on a human.
A study published in the peer-reviewed journal PLOS One reports the discovery of a beeswax filling on the left canine of a 6,500-year-old human jawbone from Slovenia. It is housed at the Natural History Museum of Trieste, Italy.
Scientists are claiming they have discovered a new species of monkey living in the remote forests of the Democratic Republic of Congo - an animal well-known to local hunters but until now, unknown to the outside world.
In a paper published Wednesday in the open-access journal Plos One, the scientists describe the new species that they call Cercopithecus Lomamiensis, known locally as the Lesula, whose home is deep in central DR Congo's Lomami forest basin. The scientists say it is only the second discovery of a monkey species in 28 years.
In an age where so much of the earth's surface has been photographed, digitized, and placed on a searchable map on the web discoveries like this one by a group of American scientists this seem a throwback to another time.
It's not exactly the kind of sugar you'd want to put in your coffee, but astronomers have found simple sugar molecules called glycolaldehyde around a star similar to our own Sun.
Here's the sweet part: Glycolaldehyde is used in the formation of RNA (a genetic material related to DNA). That makes it a building block of life.
Astronomers used the Atacama Large Millimeter/submillimeter Array (ALMA) to study the binary star IRAS 16293-2422, similar in mass to the Sun. They found glycolaldehyde around the star. The molecules were found at a distance from it comparable to the distance between Uranus and the Sun.
This is the first time that these building-block sugar molecules have been found around such a star.
"If we can show that the same molecules exist around additional Sun-like stars, that would be an indication that they also have been present around the Sun 4.5 billion years ago," lead study author Jes Jørgensen, of the Neils Bohr Institude in Denmark, said in an e-mail. "This is the first evidence that these simple pre-biotic molecules are present around Sun-like stars on scales where planets and comets may be forming."
The glycolaldehyde molecules, aside from being present around a Sun-like star, are also moving towards one of the stars in the binary system. In a release, Cecile Favre of Aarhus University in Denmark and one of the members of the research team, said, "The sugar molecules are not only in the right place to find their way onto a planet, but they are also going in the right direction."
So why is this important? Further research could show how life might arise on another planet. Jørgensen is careful to point out, however, that the discovery of glycolaldehyde is a very, very preliminary step in figuring out how organic life as we know it might have begun.
"For us, the main question now is whether we can show through similar kinds of observations that the chemical complexity can be taken even further," he said.
Glycolaldehyde molecules could make their way into proto-planetary discs around young stars, leading to the formation of planets or becoming a part of the material comets are made of, Jørgensen said. Either way, they could become part of young planets.
Scientists in Austria recently revealed a secret bigger than Victoria’s.
While excavating Lengberg Castle in 2008, a group of archaeologists led by the University of Innsbruck’s Dr. Harald Stadler unearthed a sack from a recess in the floor. Inside, they found underwear, shoes and four linen pieces that looked like bras. The castle was first documented in 1190, but archaeologists suspect the sack and its contents were left there during a renovation in the 15th century.
Many people believe the modern bra was invented after corsets, and was a revolutionary result of late 19th and early 20th century style and engineering. But the "treasure chest" of chest wear suggests that the bra as we know it is just the most recent overhaul in a long line of similarly shaped breast supports.
"(The find) reminds people not to assume we already know everything, and to keep an open mind to possible new discoveries about our history," said Beatrix Nutz, a member of Stadler's team who he commissioned to research the textiles in 2009.
“I don’t think they quite revolutionize the history of underwear, but this find certainly will modify it,” says Valerie Steele, director and chief curator of the Museum at the Fashion Institute of Technology, who was not involved in the research. “I think it means people should go back and look a bit more carefully at other garments and images in antiquities collections, to focus on something that may be more ignored."
The four newly discovered bras include two that resemble crop tops with bag-like cups, a decorated piece with thick shoulder straps and bags, and one that surprised Nutz with its similarity to lingerie in the 20th century.
“The one that I myself like to compare to a modern ‘long-line bra’ does look as if it could have been fashioned not 100 years ago,” Nutz said of the bra, which has thin straps and minimal cups. “The radiocarbon dates proved otherwise.”
Two of bras – in addition to a pair of underpants, a girls dress and a shirt fragment – have been carbon dated to the 15th century, Nutz said. This coincides with the idea that the garments were disposed of during the recorded renovation of Lengberg Castle.
Similarities between the medieval bras and our current collection of demis, push-ups and racer backs end pretty quickly in the realm of construction.
The medieval bras are linen while modern bras take advantage of synthetic fibers. Additionally, Nutz’s "long-line" bra fastens at the side instead of the back, cup sizes didn’t exist in the 15th century, and, of course, the Lengberg bras are all hand-sewn.
Curious to see how these bras fit into medieval chronology, Nutz began a personal inquiry into the history of underwear in general. She also contacted peers in Germany and France for help finding mentions of undergarments in medieval texts. What she found out was that, apart from differences in form, these bras also served functions different from those desired today.
Where most bras today are worn to highlight contents of all sizes, breasts deemed too large found their ways into "breast bags" in order to minimize their appearance.
“These ‘bags’ would have been utilitarian,” Nutz said.
Bras meant to highlight were used in private.
“Only the wearer herself and her husband would have seen them,” Nutz said. “As all ‘bras’ are decorated in some way it must be suspected that the wife would have at least wanted to look nice for her husband.”
Because the recently discovered bras are decorative, they would belong to members of the elite, Steele said.
“Linen was fairly widely used, but to have linen as underclothing helps protect your outerwear from your dirty body,” Steele said. “You can wash linen, you can’t easily wash silk or velvet or fur.”
Women were also discouraged from wearing underpants if they weren’t wealthy (those who did were assumed to discard them frequently in the company of men), but it is not yet known if the underpants found in the sack were men’s or women’s garments.
Despite differences, Nutz said that the medieval finds meet criteria for bras. The newly found bras have cups, where ancient Mediterranean "bras" were “simple strips of cloth or leather wound around the breasts and designed to flatten rather than enhance,” she wrote.
Even so, the presence of enhancing bras could represent the growing European fascination with empires of old, Steele said.
“In the 1500s, you certainly had people becoming increasingly aware of antiquity and ancient Rome, so I think that’s possible,” Steele said.
Steele said that bras called strophiums were common in ancient Rome, and indicative of class and style.
“Only the lowest class prostitute would take it off during sex. It has erotic significance as well as ‘breast support,’” Steele said. Mosaics do, however, depict Roman women wearing bandeau-like bikini tops while engaging in athletics.
Even so, bra-wearing wasn’t well received in the middle ages. Could wearing bras, then, have been a statement about standards for women?
“I don’t think it was a protest,” said Nutz, noting that progressive fashions have been worn throughout history without necessarily having social agendas. “Some people don’t like them because they’re too skimpy, and most things are met with skepticism at first.”
The question of how galaxies form is a hot issue among astronomers. Computer models have helped them make educated guesses about how these groups of stars come to be, but it's been hard to validate these theories.
Now scientists have made a significant stride in confirming part of the story of galaxy formation. They believe they have found several examples of dark galaxies, dense clouds of gas that essentially don't have stars, so they can't be detected with optical telescopes.
"This may be considered the building blocks of galaxies," said Sebastiano Cantalupo, postdoctoral fellow at the University of California, Santa Cruz and lead author of the study. "What we believe is that this is an evolutionary phase into the whole history of galaxies."
Basically, a dark galaxy is the middle stage between a diffuse cloud of gas, and a galaxy as we know them, with a lot of stars.