Current and future Mars trips take shape - NASA's Mars missions take shape, out there and back here Getting to Mars, Part 3: While probe approaches Red Planet, NASA gets set for crew vehicle By Jay Barbree CAPE CANAVERAL, Fla. - While one spaceship capable of reaching Mars closes in on its destination, another Mars-worthy craft is just beginning to take shape here at America's spaceport. Cape Canaveral is where the Mars Science Laboratory was launched four and a half months ago, carrying a rover named Curiosity toward the Red Planet. Now MSL is almost 50 million miles from Earth. It has more than 30 million miles to go before it reaches Mars. As it travels, MSL's instruments monitor the spacecraft's exposure to radiation - information that will be needed for planning future human missions through deep space. Open Road Integrated Media If all continues to go well, the craft's "sky crane" will lower the car-sized rover to the Martian surface on Aug. 6, to explore the 96-mile-wide Gale Crater and its 3-mile-high Mount Sharp, and carry out a nearly two-year-long hunt for the chemical building blocks of life. While Curiosity does its work, experienced hands will be working as well at NASA's Kennedy Space Center, on a different kind of Mars ship that could follow up on the rover's discoveries. The center of activity is a historic high bay building called the "O&C" - short for Operations & Checkout. Decades ago, the O&C was used to prepare Apollo spacecraft for their trips to the moon. Now the facility has been rebuilt into a state-of-the-art spaceship factory, to turn out the ships that could eventually carry humans to Mars. The 150 men and women who work at the O&C used to work on NASA's space shuttles. Now they're ready and eager to build that Mars ship. It is called Orion. Named for mythology's giant-size hunter, this Orion will hunt down new ports in our solar system. Its inaugural unmanned test flight is less than two years away. Historically, NASA's spaceships have been built elsewhere and then transported cross-country to their launch site. But Lockheed Martin is taking a new approach for Orion's construction. "You build and you test on-site, and you save time and money," said Glenn Chin, NASA's deputy manager for the Orion development effort. That's a big deal in the current political environment. During the Cold War, the cost of getting to the moon was of secondary concern. But today, NASA's ambitions have to fit within tight budgetary limits. The current plan calls for NASA and its contractors to build Orion as well as a new heavy-lift launch vehicle called the Space Launch System, or SLS. The budget proposal for the next fiscal year sets aside $2.8 billion for those programs. If they are permitted to go forward, Orion and SLS will ensure America's continued leadership in space. The gleaming-new Orion factory is expected to employ 190 by the end of the year, says Jim Kemp, Lockheed Martin's director of Orion assembly, testing and launch. By the time Orion makes it maiden flight in late 2013 or early 2014, 350 to 400 spaceflight veterans will be working in the Florida factory. A beefy United Launch Alliance Delta 4 rocket is due to send the first Orion speeding away from Earth to a height of 5,000 miles. Then the craft would arc back to Earth at a velocity exceeding 20,000 mph. If the re-entry angle is too shallow, Orion could skip off Earth's atmosphere, like a rock skipping across the surface of a lake. This would doom a human crew to spend eternity moving through our galaxy. If the angle is too steep, the blazing re-entry would turn the ship and its crew into a handful of ashes. Such danger-filled reentries were pioneered by the Apollo flights. 'Apollo 8"s Return': An excerpt from 'Moon Shot' Fifty-eight hours after leaving the moon, Earth used its gravity to drag Apollo 8 back into the atmosphere at 25,000 miles an hour. The fastest spacecraft ever then began a brief life as a man-made meteor. Temperatures soared to what could be found on the surface of a star. Plunging downward with their backs to their line of flight, the astronauts knew their existence now depended upon how well their ship had been built. No one saw Apollo 8 hurtling through Earth's layers of protecting atmosphere. Only fire could be seen, intense, blinding white flames with an outer red sheath, a streamer of fire 125 miles long! Apollo 8 traded off its tremendous speed for heat. The more fire flowing from the heat shield, the slower flew the spaceship. Then they were through the inferno of re-entry. Two miles above the Pacific Ocean, just before dawn, three large parachutes streamed away from the ship, opened partially for deceleration, then blossoming wide and full. Back to the future While Orion is readied for its inaugural flight, plans for its first manned mission to a near-Earth asteroid move ahead. That launch is now scheduled for 2024, with a crew of four spending up to a year in space. NASA sees near-Earth asteroids as steppingstones that will lead to Mars missions in the 2030s. Can it be done in this economy? Certainly, if NASA spends its dollars on the tasks that Congress created the space agency to do: to explore, to break new ground, to give us more knowledge of our solar system and make us worthy custodians of Earth. Stay tuned for humankind's first trek into deep space, coming in the not-too-distant future. In the grand scheme of things, the 12 years until that unprecedented asteroid mission represent a hardly noticeable tick of the universe's clock. More from 'Getting to Mars': More from 'Moon Shot': NBC News' Jay Barbree is the only journalist to cover every spaceflight flown by astronauts from Cape Canaveral. He has won NASA's highest medal for public service and the National Space Club's 2009 Press Award. Barbree also has written several books about the space effort, including an updated version of "Moon Shot: The Inside Story of America's Apollo Moon Landings," published by Open Road Integrated Media and available from Apple iBookstore, BarnesandNoble.com, Amazon.com, Sony Reader Store and Kobo Books. "Moon Shot" excerpt updated and reprinted with permission, copyright 2011.