Mars Express encountered Phobos last night, smoothly skimming past at just 67 km, the closest any manmade object has ever approached Marsâ€™ enigmatic moon. The data collected could help unlock the origin of not just Phobos but other â€˜second generationâ€™ moons.
Something is not right about Phobos. It looks like a solid object but previous flybys have shown that it is not dense enough to be solid all the way through. Instead, it must be 25-35% porous. This has led planetary scientists to believe that it is little more than a â€˜rubble pileâ€™ circling Mars. Such a rubble pile would be composed of blocks both large and small resting together, with possibly large spaces between them where they do not fit easily together.
Stickney Crater, the largest crater on the martian moon Phobos, is named for Chloe Angeline Stickney Hall, mathematician and wife of astronomer Asaph Hall. Asaph Hall discovered both the Red Planet’s moons in 1877.
Over 9 kilometers across, Stickney is nearly half the diameter of Phobos itself, so large that the impact that blasted out the crater likely came close to shattering the tiny moon. This stunning, enhanced-color image of Stickney and surroundings was recorded by the HiRISE camera onboard the Mars Reconnaissance Orbiter as it passed within some six thousand kilometers of Phobos in March of 2008.
Even though the surface gravity of asteroid-like Phobos is less than 1/1000th Earth’s gravity, streaks suggest loose material has slid down inside the crater walls over time. Light bluish regions near the crater’s rim could indicate a relatively freshly exposed surface. The origin of the curious grooves along the surface is mysterious but may be related to the crater-forming impact.
As reported earlier, Roskosmos has decided to postpone a planned sample return from the Martian moon Phobos by two years to 2011, citing problems with integration and testing. Or, to put it more bluntly, to avoid the nation’s 21st straight failure at Mars.
The massive 12 ton Phobos-Grunt spacecraft was set for launch next month from Baikonur. It would be Russia’s first mission to the Red Planet since the ill-fated Mars 96 mission, which was lost in a booster failure.
The mission includes the 240-lb. Yinghou-1 sub-satellite supplied by China. This would be the first interplanetary mission by the Asian nation.
China’s first Mars probe has been transported to Moscow along with a team of Chinese scientists, Beijing News reported on August 6, 2009.
After passing the research phase, China’s first ever Mars probe Yinghuo-1 was sent to Russia for compatibility tests and it will take off atop a Russian launch vehicle from Baikonur Cosmodrome space base in Kazakhstan in October.
Russian interplanetary probe Phobos-Grunt will have passengers. There are earth`s bacteria. They will fly from the Earth to Mars and back and undergo space cold and radiation. Scientists want to use the bacteria to find out whether life of our planet could have been brought from space.
Lev Zeleny, director of RAS Space Research Institute, explains that the goal of this mission is to check if bacteria can survive in outer space, for example, if they fly on the surface of meteor.
Space.com takes a look at missions being planned for the Martian moon Phobos. Most of the story is about Russia’s massive Phobos-Grunt spacecraft, which is designed to return soil samples to Earth. That mission was set for launch later this year, but it will likely be delayed for two years.
Mars Express closed in on the intriguing martian moon Phobos at 6:49 CEST on 23 July, flying past at 3 km/s, only 93 km from the moon. The ESA spacecraftâ€™s fly-bys of the moon have returned its most detailed full-disc images ever, also in 3-D, using the High Resolution Stereo Camera on board.
Phobos is what scientists call a â€˜small irregular bodyâ€™. Measuring 27 km Ã— 22 km Ã— 19 km, it is one of the least reflective objects in the Solar System, thought to be a capture-asteroid or a remnant of the material that formed the planets.
The best images of Phobos ever
The HRSC images, which are still under processing, form a bounty for scientists studying Phobos. They are a result of observations carried out over several close fly-bys of the martian moon, performed over the past three weeks. At their best, the pictures have a resolution of 3.7 m/pixel and are taken in five channels (in the stereo channel) for images in 3-D and (in the photometric channels) to perform analyses of the physical properties of the surface.
Image credit: NASA/JPL-Caltech/University of Arizona
NASA PRESS RELEASE
The High Resolution Imaging Science Experiment (HiRISE) camera on NASA’s Mars Reconnaissance Orbiter took two images of the larger of Mars’ two moons, Phobos, within 10 minutes of each other on March 23, 2008. This is the first, taken from a distance of about 6,800 kilometers (about 4,200 miles). It is presented in color by combining data from the camera’s blue-green, red, and near-infrared channels.
The illuminated part of Phobos seen in the images is about 21 kilometers (13 miles) across. The most prominent feature in the images is the large crater Stickney in the lower right. With a diameter of 9 kilometers (5.6 miles), it is the largest feature on Phobos.