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a grey, lumpy moon in front of the red surface of Mars Credit: Emirates Mars Mission The United Arab Emirates Space Agency (UAESA) has just produced the best images ever taken of Mars’ moon Deimos — and they suggest the tiny satellite isn’t what we thought it was. Mars’ moons: Mars has two moons. The larger of them, Phobos, is 14 miles wide and orbits the planet from a distance of just 3,700 miles, while the smaller one, Deimos, is only 9 miles in diameter and circles it from 14,580 miles away. “We expect to … advance our fundamental understanding...

Europe's Mars Express spacecraft has peered deeper into the subsurface of the Martian moon Phobos than ever before, finding hints of unknown structures that could be clues as to the moon's origin. Mars Express, which is a 19-year-veteran spacecraft in orbit around Mars, came within 51.6 miles (83 kilometers) of Phobos on Sept. 22, 2022 and was able to probe beneath the moon's surface using upgraded software on its MARSIS instrument (Mars Advanced Radar for Subsurface and Ionosphere Sounding). Understanding the interior structure of Phobos could be key in solving the mystery of its origin. A close-up of the Martian...

One of Jupiter's tenuous rings can be seen in this infrared image. (NASA/ESA/CSA/STScI/Judy Schmidt) Given its similarities to its neighbor, Saturn, it seems natural to ask why Jupiter doesn't also have a magnificent, extensive system of visible rings. Alas, it's not the reality. While Jupiter does have rings, they're thin, tenuous, flimsy things of dust, visible only when back-lit by the Sun. According to new research, these discount rings lack bling because Jupiter's posse of chonky Galilean moons keep discs of rock and dust from accumulating the way they do around Saturn. "It's long bothered me why Jupiter doesn't have...

Explanation: This moon is doomed. Mars, the red planet named for the Roman god of war, has two tiny moons, Phobos and Deimos, whose names are derived from the Greek for Fear and Panic. These martian moons may well be captured asteroids originating in the main asteroid belt between Mars and Jupiter or perhaps from even more distant reaches of our Solar System. The larger moon, Phobos, is indeed seen to be a cratered, asteroid-like object in this stunning color image from the robotic Mars Reconnaissance Orbiter, with objects as small as 10 meters visible. But Phobos orbits so close...

NASA’s Perseverance Mars rover used its Mastcam-Z camera to shoot video of Phobos, one of Mars’ two moons, eclipsing the Sun. It’s the most zoomed-in, highest-frame-rate observation of a Phobos solar eclipse ever taken from the Martian surface. ==> CLICK HERE to see a 49 second YouTube video of the eclipseThe Mastcam-Z camera recorded video of Phobos, one of the Red Planet’s two moons, to study how its orbit is changing over time. NASA’s Perseverance Mars rover has captured dramatic footage of Phobos, Mars’ potato-shaped moon, crossing the face of the Sun. These observations can help scientists better understand the...

hese experiments are designed to give agencies a better idea of how humans would interact and cope during a long space journey. The volunteer research subjects start their virtual journey to Phobos on October 1, in a ground-based habitat at NASA's Johnson Space Center in Houston, Texas. Their home for the 45 days will be a small habitat called the Human Exploration Research Analog, or HERA - with collected data informing the design of future missions to the Red Planet, expected to happen in the 2030s. HERA is a two-story, four-port cylindrical habitat unit with a total of 636 sq....

A mysterious origin and Arthur C. Clarke-level science-fiction speculation about the 17-mile-wide, deeply-grooved moon as an alien artifact captured in the ancient past by Mars gravitational field, may explain Russia’s almost mystical obsession with Phobos. First the Soviet Union, then more recently, Russia, made three attempts to reach the enigmatic object, but software errors and launch disasters have aborted each attempt. In 2016 the BBC reported that a mysterious monolith object was spotted several years ago by a NASA probe, and to this day nobody is quite sure what it is or how it got there. Japan is on deck,...

Japan’s space agency has approved a robotic mission to retrieve a sample from the Martian moon Phobos for return to Earth to begin full development for a planned launch in 2024, officials said Thursday. The Martian Moon eXploration, or MMX, spacecraft will attempt to return the first specimens from Phobos for analysis in laboratories on Earth, where scientists hope to trace the origins of the Martian moons to determine whether they were asteroids captured by Mars, or if they formed out of rocky debris generated from an ancient impact on Mars. The Japan Aerospace Exploration Agency and other Japanese government...

Credit: NASA/Viking 1 Orbiter Apr 03, 2008Fantastic Phobos Conventional theory states that Phobos has been marred by repeated meteor impacts, but could electricity have played a significant role? Phobos is the largest of the two moons of Mars. Deimos is so small that studying its surface has been problematic for astronomers because it cannot be readily observed from Earth. Only the Viking 2 orbiter captured close up images. Phobos, on the other hand, has been examined by Earth stations and by satellites sent to Mars orbit. In the image above, Stickney crater is visible - a ten kilometer-wide excavation that...

Explanation: Why is the northern half of asteroid Vesta more heavily cratered than the south? No one is yet sure. This unexpected mystery has come to light only in the past few weeks since the robotic Dawn mission became the first spacecraft to orbit the second largest object in the asteroid belt between Mars and Jupiter. The northern half of Vesta, seen on the upper left of the above image, appears to show some of the densest cratering in the Solar System, while the southern half is unexpectedly smooth. Also unknown is the origin of grooves that circle the asteroid...

Phobos’ grooves, which are visible across most of the moon’s surface, were first glimpsed in the 1970s by NASA’s Mariner and Viking missions.Over the years, there has been no shortage of explanations put forward for how they formed.Some planetary researchers have posited that large impacts on Mars have showered the nearby moon with groove-carving debris. Others think that Mars’ gravity is slowly tearing Phobos apart, and the grooves are signs of structural failure.Still other scientists have made the case that there’s a connection between the grooves and the impact that created a large crater called Stickney.In the 1970s, University of...

Stickney Crater Credit: HiRISE, MRO, LPL (U. Arizona), NASA Explanation: 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...

Phobos from Mars Express Credit: G. Neukum (FU Berlin) et al., Mars Express, DLR, ESA Explanation: Why is this small object orbiting Mars? The origin of Phobos, the larger of the two moons orbiting Mars, remains unknown. Phobos and Deimos appear very similar to C-type asteroids, yet gravitationally capturing such asteroids, circularizing their orbits, and dragging them into Mars' equatorial plane seems unlikely. Pictured above is Phobos as it appeared during last week's flyby of ESA's Mars Express, a robotic spacecraft that began orbiting Mars in 2003. Visible in great detail is Phobos' irregular shape, strangely dark terrain, numerous...

Known as the Martian Moons Exploration (MMX) mission, the plan is to have a robotic spacecraft fly to Phobos and Deimos to explore their surfaces and return samples to Earth for analysis. The spacecraft would be deployed sometime in the 2020s, and would be tasked with two main objectives. The first would be to help scientists determine the origins of Phobos and Deimos, which has been a subject of debate for some time. Whereas some believe that these moons are capture asteroids, others have argued that they were created when fragments ejected from Mars (due to giant impacts on the...

NASA's Mars Atmosphere and Volatile Evolution Mission (MAVEN) is coming up on its second year studying the Red Planet's atmosphere. But it had to make an unexpected maneuver this week as it came face to face with an unlikely foe—a Martian moon named Phobos. The larger of Mars' two moons, Phobos' defining feature is a giant crater on its surface, Stickney, and a smaller crater within that crater, Limtoc. It moves around Mars faster than Mars rotates, and it became clear last week that it was going to be on a course missing the MAVEN satellite by only seven seconds....

A volcano on Mars half the size of France spewed so much lava 3.5 billion years ago that the weight displaced the Red Planet's outer layers, according to a study released Wednesday. Mars' original north and south poles, in other words, are no longer where they once were. The findings explain the unexpected location of dry river beds and underground reservoirs of water ice, as well as other Martian mysteries that have long perplexed scientists, the lead researcher told AFP. "If a similar shift happened on Earth, Paris would be in the Polar Circle," said Sylvain Bouley, a geomorphologist at...

Did a giant impact create the two faces of Mars? 16:29 15 March 2007 NewScientist.com news service David Shiga, Houston Mars's northern hemisphere is lower in elevation – by about 5 kilometres – than its southern hemisphere (see image below). This coloured topographical map shows low elevations in blue and high elevations in yellow and red. The map is centred on a latitude of 55° north (Illustration: Mike Caplinger/MSSS) Mars's southern hemisphere is higher and more heavily cratered than the northern hemisphere, suggesting it is older terrain. The two low elevations (blue) in this map, which is centred on the...

Jafar Arkani-Hamed of McGill University discovered that five impact basins--dubbed Argyre, Hellas, Isidis, Thaumasia and Utopia--form an arclike pattern on the Martian surface. Three of the basins are well-preserved and remain visible today. The locations of the other two, in contrast, were inferred from measurements of anomalies in the planet's gravitational field... a single source--most likely an asteroid that was initially circling the sun in the same plane as Mars--created all five craters. At one point the asteroid passed close to the Red Planet... and was broken apart by the force of the planet's gravity. The resulting five pieces subsequently...

Asteroid Vesta: The 10th Planet? Discovery Brightens Odds of Finding Another Pluto Nemesis: The Million Dollar Question HOUSTON, TEXAS -- Our solar system may have had a fifth terrestrial planet, one that was swallowed up by the Sun. But before it was destroyed, the now missing-in-action world made a mess of things. Space scientists John Chambers and Jack Lissauer of NASA's Ames Research Center hypothesize that along with Mercury, Venus, Earth, and Mars -- the terrestrial, rocky planets -- there was a fifth terrestrial world, likely just outside of Mars's orbit and before the inner asteroid belt. Moreover, Planet V...

Phobos and Deimos are both small for moons — about 14 and 7.7 miles (22.5 and 12.4 kilometers) wide, respectively — and sort of potato-shaped. Compared to other satellites in the solar system, they look more like asteroids. As a result, astronomers previously hypothesized that these moons were asteroids captured by Mars' gravitational pull. ...previous research suggested that Phobos and Deimos would have relatively irregular orbits. In reality, these moons have nearly circular orbits positioned near the Martian equator. ... huge impact that previous research suggested created the gigantic Borealis basin in the northern lowlands of Mars, which covers two-fifths...