Phobos

Mars’ mysterious moon Phobos captured in new NASA images

There are more than 200 moons in the Solar System, including Phobos and Deimos, which orbit Mars. NASA’s Odyssey orbiter has snapped new pictures of Phobos, giving new insight into the celestial satellite. In a blog post, NASA JPL notes Odyssey took three new views of the 16-mile wide Phobos this past winter and spring. The new pictures show that heat distribution across the moon’s surface varies in different conditions, which could give researchers new insight into what comprises Phobos. “We’re seeing that the surface of Phobos is relatively uniform and made up of very fine-grained materials,” said Christopher Edwards of Northern Arizona University, who is leading the processing and analysis of the Phobos images, in a statement. “These observations are also helping to characterize the composition of Phobos. Future observations will provide a more complete picture of the temperature extremes on the moon’s surface.” The images were taken using the orbiter’s Thermal Emission Imaging System (THEMIS) camera, which is capable of measuring temperature. Mars’ moons have been of interest to researchers in recent memory. A study published earlier this month suggested that Mars may have also once been a ringed planet. The researchers pointed out that one of Mars’ moons, Deimos, has a slightly altered orbit that suggests there was something responsible for its slight tilt. Researchers are learning more about Mars’ ancient past. A study published in March suggested the Red Planet had two unique reservoirs of ancient water that once flowed deep beneath the planet’s surface. NASA’s long-term goal is to send a manned mission to Mars in the 2030s. Click here to see Odyssey’s photos of Phobos.

Very cool!!      🙂

NASA releases new ultraviolet image of Mars’ moon Phobos

NASA has released a new image of Mars’ moon Phobos, allowing scientists to better assess the mysterious object. The space agency’s Mars Atmosphere and Volatile Evolution (MAVEN) mission made a series of close approaches to Phobos in late November and early December 2015, according to a NASA statement. “Among the data returned were spectral images of Phobos in the ultraviolet,” NASA explained. “The images will allow MAVEN scientists to better assess the composition of this enigmatic object, whose origin is unknown.” NASA explained that comparing MAVEN’s images and spectra of the surface of Phobos to data from asteroids and meteorites will help scientists understand whether the moon is “a captured asteroid” or was formed in orbit around Mars. The data will be useful to scientists look for organic molecules on Phobos’ surface, the space agency said. Last year scientists explained that Phobos may be heading for destruction, noting the spatial cracks crisscrossing the moon’s surface – much like cracks in the foundation of your home.

Fascinating!  To see the photo in question, click on the text above.    🙂

Mars’ moon Phobos could be headed for destruction

It’s hard to miss the groove marks that crisscross the moon Phobos. But rather than scars from a past encounter with an asteroid or another space object, NASA scientists believe they reflect the structural failure – much like cracks in the foundation of your home – of the larger of Mars’ two moons. Ultimately, these spatial cracks will result in the destruction of Phobos. “We think that Phobos has already started to fail, and the first sign of this failure is the production of these grooves,” said Terry Hurford of NASA’s Goddard Space Flight Center in Greenbelt, Maryland. Orbiting 3,700 miles above the surface of Mars, Phobos is closer to its planet than any other moon in the solar system. That is part of the problem. Mars’ gravity is drawing in Phobos by about 6.6 feet every hundred years. Making things even worse for Phobos is a belief that its interior could be a rubble pile surrounded by a layer of powdery regolith. Not exactly a rock, solid moon. But don’t worry; the demise of Phobos is some time away. Scientists expect the moon to be pulled apart in 30 to 50 million years. Initially, scientists thought the grooves were created by the massive impact that made Stickney crater. That collision was so powerful, it came close to shattering Phobos. More recently, researchers thought the grooves were a result of material being ejected by Mars. But new modeling by Hurford and colleagues supports the view that the grooves are more like “stretch marks” that occur when Phobos gets deformed by tidal forces. The gravitational pull between Mars and Phobos produces these tidal forces, similar to how Earth and our moon pull on each other and produce tides in the oceans. The findings by Hurford and his colleagues are being presented this week at the annual Meeting of the Division of Planetary Sciences of the American Astronomical Society at National Harbor, Maryland. “The funny thing about the result is that it shows Phobos has a kind of mildly cohesive outer fabric,” said Erik Asphaug of the School of Earth and Space Exploration at Arizona State University in Tempe and a co-investigator on the study. “This makes sense when you think about powdery materials in microgravity, but it’s quite non-intuitive.” The same fate may await Neptune’s moon Triton, which is also slowly falling inward and has a similarly fractured surface. The work also has implications for extrasolar planets, according to researchers. “We can’t image those distant planets to see what’s going on, but this work can help us understand those systems, because any kind of planet falling into its host star could get torn apart in the same way,” Hurford said.

Fascinating!! 🙂