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Artist's illustration of the U.S. Air Force's X-37B space plane in orbit. The mysterious spacecraft is scheduled to launch on its fourth mission on May 20, 2015. Credit: NASA Marshall Space Flight Center |
Excerpt from space.com
The United States Air Force's X-37B space plane will launch on its fourth mystery mission next month.
The unmanned X-37B space plane, which looks like a miniature version of NASA's now-retired space shuttle orbiter, is scheduled to blast off atop a United Launch Alliance Atlas V rocket from Florida's Cape Canaveral Air Force Station on May 20.
"We are excited about our fourth X-37B mission," Randy Walden, director of the Air Force Rapid Capabilities Office, said in a statement. "With the demonstrated success of the first three missions, we’re able to shift our focus from initial checkouts of the vehicle to testing of experimental payloads."
The X-37B's payloads and specific activities are classified, so it's unclear exactly what the spacecraft does while zipping around the Earth. But Air Force officials have revealed a few clues about the upcoming mission.
"The Air Force Research Laboratory (AFRL), Space and Missile Systems Center (SMC) and the Air Force Rapid Capabilities Office (AFRCO) are investigating an experimental propulsion system on the X-37B on Mission 4," Capt. Chris Hoyler, an Air Force spokesman, told Space.com via email.
"AFRCO will also host a number of advance materials onboard the X-37B for the National Aeronautics and Space Administration (NASA) to study the durability of various materials in the space environment," Hoyler added.
The Air Force owns two X-37B space planes, both of which were built by Boeing's Phantom Works division. The solar-powered spacecraft are about 29 feet long by 9.5 feet tall (8.8 by 2.9 meters), with a wingspan of 15 feet (4.6 m) and a payload bay the size of a pickup-truck bed. The X-37B launches vertically atop a rocket and lands horizontally on a runway, like the space shuttle did.
One of the two X-37B vehicles flew the program's first and third missions, which were known as OTV-1 and OTV-3, respectively. ("OTV" is short for "Orbital Test Vehicle.") The other spacecraft flew OTV-2. Air Force officials have not revealed which space plane will be going to orbit on the upcoming mission.
OTV-1 launched in April 2010 and landed in December of that year, staying in orbit for 225 days. OTV-2 blasted off in March 2011 and circled Earth for 469 days, coming down in June 2012. OTV-3 launched in December 2012 and stayed aloft for a record-breaking 675 days, finally landing in October 2014.
Credit: Boeing
If Air Force officials know how long OTV-4 is going to last, they're not saying.
"The X-37B is designed for an on-orbit duration of 270 days," Hoyler said. "Longer missions have been demonstrated. As with previous missions, the actual duration will depend on test objectives, on-orbit vehicle performance and conditions at the landing facility."
The secrecy surrounding the X-37B and its payloads has fueled speculation in some quarters that the vehicle could be a space weapon of some sort. But Air Force officials have repeatedly refuted that notion.
"The primary objectives of the X-37B are twofold: reusable spacecraft technologies for America's future in space, and operating experiments which can be returned to, and examined, on Earth," Air Force officials wrote in on online X-37B fact sheet.
"Technologies being tested in the program include advanced guidance, navigation and control; thermal protection systems; avionics; high-temperature structures and seals; conformal reusable insulation, lightweight electromechanical flight systems; and autonomous orbital flight, re-entry and landing."
Spacecraft found on Mars – and it’s ours
Excerpt from skyandtelescope.com
By Kelly Beatty
On December 25, 2003, a British-built lander dropped to the Martian surface and disappeared without a trace. Now we know what happened to it. It's hard to overstate how valuable the main camera aboard the Mars Reconnaissance Orbiter has been. The craft's High-Resolution Imaging Science Experiment, or HiRISE, uses a 20-inch (0.5-m) f/24 telescope to record details on the Martian surface as small as 0.3 m (about 10 inches).
Primarily it's a powerful tool for studying Martian geology at the smallest scales, and NASA scientists sometimes use it to track the progress (and even the arrivals) of their rovers. Beagle 2 on Mars The clamshell-like Beagle 2 lander weighed just 30 kg, but it was well equipped to study Martian rocks and dust — and even to search for life. Beagle 2 consortium But the HiRISE team has also been on a years-long quest to find the remains of Beagle 2, a small lander that had hitchhiked to the Red Planet with the European Space Agency's Mars Express orbiter. It descended to the Martian surface on Christmas Day in 2003 and was never heard from again. Space aficionados have debated its fate ever since. Did parachute failure lead to a crash landing? Did strong surface winds flip the saucer-shaped craft upside down? Did the Martians take it hostage? Now, thanks to HiRISE, we know more of the story.
Images taken in February 2013 and June 2014 of the landing area in Isidis Planitia showed promising blips near the edge of each frame. A follow-up color view, acquired on December 15th and released three days ago, show a bright spot consistent with Beagle 2. The fully-opened lander would have been less than 2 m (6½ feet) across, so the craft is only barely resolved. Apparently the spacecraft made it to the surface intact, opened its clamshell cover, and had partially deployed its four petal-shaped solar-cell panels before something went awry. Beagle 2 seen from orbit by HiRISE
One encouraging clue is that the bright reflection changes position slightly from image to image, consistent with sunlight reflecting off different lander panels. Two other unusual spots a few hundred meters away appears to be the lander's parachute and part of the cover that served as a shield during the 5½-km-per-second atmospheric descent...
It's hard to overstate how valuable the main camera aboard the Mars Reconnaissance Orbiter has been. The craft's High-Resolution Imaging Science Experiment, or HiRISE, uses a 20-inch (0.5-m) f/24 telescope to record details on the Martian surface as small as 0.3 m (about 10 inches). Primarily it's a powerful tool for studying Martian geology at the smallest scales, and NASA scientists sometimes use it to track the progress (and even the arrivals) of their rovers.
Beagle 2 consortium
Now, thanks to HiRISE, we know more of the story. Images taken in February 2013 and June 2014 of the landing area in Isidis Planitia showed promising blips near the edge of each frame. A follow-up color view, acquired on December 15th and released three days ago, show a bright spot consistent with Beagle 2. The fully-opened lander would have been less than 2 m (6½ feet) across, so the craft is only barely resolved. Apparently the spacecraft made it to the surface intact, opened its clamshell cover, and had partially deployed its four petal-shaped solar-cell panels before something went awry.
NASA / JPL / Univ. of Arizona / Univ. of Leicester
The initial images didn't just show up. They'd been requested and searched by Michael Croon of Trier, Germany, who'd served on the Mars Express operations team. Croon had asked for specific camera targeting through a program called HiWish, through which anyone can submit suggestions for HiRISE images. Read more about this fascinating sleuthing story.
"Not knowing what happened to Beagle 2 remained a nagging worry," comments Rudolf Schmidt in an ESA press release about the find. "Understanding now that Beagle 2 made it all the way down to the surface is excellent news." Schmidt served as the Mars Express project manager at the time.
Built by a consortium of organizations, Beagle 2 was the United Kingdom's first interplanetary spacecraft. The 32-kg (73-pound) lander carried six instruments to study geochemical characteristics of the Martian surface and to test for the presence of life using assays of carbon isotopes. It was named for HMS Beagle, the ship that carried a crew of 73 (including Charles Darwin) on an epic voyage of discovery in 1831–36.
- See more at: http://www.skyandtelescope.com/astronomy-news/beagle-2-lander-found-on-mars-01192015/#sthash.5KSZ8V6W.dpuf