Discovered in 1877 by the American astronomer Asaph Hall, the enigmatic duo of Martian moons, nicknamed Phobos Y Demos, they have bewitched and mystified planetary scientists trying to understand their many mysteries. Martian moons are tiny, misshapen objects, often considered captured asteroids, that were trapped by the Red Planet’s gravity long ago, after they both escaped the planet. handheld asteroid belt between Mars and Jupiter. Phobos It is both the larger of the two moons, as well as the closer to its rust-colored parent planet, and orbits just 3,700 miles from the Martian surface, closer to its parent body than any other known moon in Earth. our solar system. Indeed, Phobos it is so close that it orbits its planet much faster than Mars, completing one orbit in just 7 hours and 39 minutes. In October 2017, astronomers announced that NASA’s longest-running mission to the Red Planet has gotten its first look at Phobos, in his quest to gain a deeper understanding by exploring it at infrared wavelengths.
Tea Thermal Emission Imaging System (THEMIS) NASA onboard camera Mars Odyssey Orbiter observed the small potato-shaped moon on September 29, 2017. Planetary scientists have now combined infrared and visible wavelength data to create a color-coded image for surface temperatures on this intriguing little moon. Phobos it has been considered for a possible future human mission outpost.
“Part of the observed face of Phobos was in the dark before dawn, part of morning daylight, commented THEMIS Associate Principal Investigator Dr. Victoria Hamilton on an October 4, 2017 NASA Press release from the Jet Propulsion Laboratory (JPL). Dr. Hamilton is from southwestern Research Institute, based in San Antonio, Texas. Tea JPL It’s in Pasadena, California.
Studying the new image from left to right presents a sequence of daylight hours on the mysterious Martian moon, ranging from before sunrise, to sunrise, and increasing amounts of time after Martian sunrise. This provides valuable information about how quickly the Red Planet’s soil is heating up, which is related to the texture of its rust-colored surface. Sand heats up or cools down much faster than rocks or pavement.
“Including a predawn area in the observation is useful because all the heating from the sunlight of the previous day has reached its minimum there. As you move from the predawn area to the morning area you get to see the heating behavior. If it warms up very quickly, it’s probably not going to be very rocky but dusty,” Dr. Hamilton continued to explain in the JPL press release.
ring around the Red planet
Phobos It is an irregularly shaped moon with a mean radius of just 7 miles, and it is seven times more massive than its sister moon. Demos. Phobos It is named after the Greek god Phobos, son of Ares (Mars) and Aphrodite (Venus). The mythological Phobos also serves as the personification of horror; hence the word phobia.
Because Phobos orbits Mars much faster than Mars rotates, some strange things happen in the Martian sky. From the surface of the Red Planet, Phobos appears to rise in the west, move across the sky in 4 hours and 15 minutes or less, and set in the east–twice every Martian day.
As one of the least reflective bodies in our Solar System, Phobos it has an albedo of only 0.071. Surface temperatures range from about 25 degrees Fahrenheit on the sunlit side to -170 degrees Fahrenheit on the shady side. The most notable surface feature of this small moon is the large impact crater, called stickneythat heals a very important region of Phobos surface.
Rather than being a solid body, images and models suggest that Phobos it may actually be a pile of debris held together only by a thin crust. Also, the small moon is being torn apart by tidal interactions. Phobos it travels closer to its parent planet by about 2 meters every hundred years, and it has been predicted that in about 30 to 50 million years it will collide with Mars or fragment into myriad pieces, thus forming a ring around its planet. planet.
Asaph Hall discovered Phobos on August 18, 1877, at the United States Naval Observatory in Washington DC Hall had already discovered Deimos a few days earlier, on August 12, 1877.
Phobos it has too little mass to be rounded under the influence of its own gravitational pull, and it also has no atmosphere as a result of its very low mass and low gravity. Spectroscopically, it appears to be similar to the D-type asteroidsand has a composition similar to that of carbonaceous chondrites. Phobos the density is too low for it to be made of solid rock, and it is known to be very porous. These are the results that led to a proposal that Phobos it could possibly harbor a significant reservoir of ice. Spectral observations suggest that the surface regolith layer is devoid of water. However, ice lurking beneath the regolith has not been ruled out.
This surface of this small Martian moon is also pockmarked with craters. Its most prominent crater, stickneyit is named after Hall’s wife, Angeline Stickney Hall. stickney it is a large impact crater that is about 5.6 miles in diameter and occupies a substantial proportion of the small moon’s surface area. The impact that dug stickney must have been very close to exploding Phobos besides.
The oddly shaped surface of Phobos it is marked by numerous furrows and streaks. The ruts are typically less than 98 feet deep and 330 to 660 feet wide, and can extend up to 12 miles in length. At first these strange grooves and cutting scratches were thought to be the result of the same impact that excavated Stickney. However, a careful analysis derived from the results obtained from the Mars Express spacecraft indicated that the grooves are not radial to stickneybut instead focus on the main vertex of Phobos in its orbit around Mars (which is not very far from stickney). Astronomers now suspect that they have been carved as a result of material blasted into space by impacts on the surface of the Red Planet itself. As a result, the grooves formed like chains of craters, and they all vanished as the final vertex of Phobos approaches. Astronomers have grouped them into a dozen or more families of varying ages, presumably carved out by at least 12 impacts on the Martian surface.
Very faint rings of dust created by Phobos Y Deimos have been predicted for years. However, efforts to observe these faint rings have so far been in vain. Images obtained from the Mars Global Surveyor suggest that Phobos It is covered by a mantle of fine-grained regolith at least 100 meters thick. Some astronomers have proposed that the regolith was produced by impacts from other bodies, but it is not known how the material attached itself to an object like Phobos It has almost no gravity.
Tea Kaidun Meteorite which crashed at a Soviet military base in Yemen in 1980, it has been hypothesized to be a piece of Phobos. However, this scenario has turned out to be difficult to verify. This is because little is known about the exact composition of Phobos.
Mars has not always looked the way it does today. The planet experienced a huge and catastrophic tilt billions of years ago. Before this large tilt occurred, the Martian poles were not where astronomers see them now.
The recently obtained data describing the Red Planet is derived from seven active probes cruising the Martian surface or orbiting the planet. The seven spacecraft include five orbiters and two rovers. This successful collection includes 2001 Mars Odyssey, Mars Express, Mars Reconnaissance Orbiter, MAVEN, OpportunityY Curiosity.
The United States, the Soviet Union, Europe, and India have sent many uncrewed spacecraft, including rovers, orbiters, and landers, to the Red Planet to study the climate, geology, and surface of Mars. Since the year 2000, cameras orbiting Mars have returned a treasure trove of revealing images to Earth. These images have shown that the Martian surface has been etched with small valleys and carved into slopes. These features are eerily similar in shape to gullies carved out by flowing water on Earth. Martian ravines are thought to be less than a few million years old, the blink of an eye on geologic time scales. In fact, some of the ravines may even be younger than that!
A doomed Martian moon has a story to tell
Cameras aboard Mars orbiters have previously taken higher-resolution images of Phobos. However, none of the above images were obtained with the infrared information available from FEARS. Observations at multiple bands of thermal infrared wavelengths can provide information about the mineral composition of the small moon’s surface, as well as its surface texture.
An intriguing question about Phobosas well as her younger sister, the moon, Deimos, is whether they really are captured asteroids or, alternatively, chunks of Mars thrown into the sky by impacts. composition information of THEMIS could finally help astronomers determine its origin.
As Odyssey began orbiting Mars in 2001, THEMIS has provided scientists with information about the thermal and compositional properties that exist on the entire Red Planet, but never before on either of the two Martian moons. The observations made on September 29, 2017 were completed to show that the spacecraft could do so safely, as the beginning of a possible series of observations of Phobos Y Deimos in the coming months.
In normal operating mode, Odyssey keep the THEMIS the camera is pointed directly downward as the spacecraft orbits the Red Planet. In 2014, the spacecraft team in Lockheed Martin Space Systemsin Denver, Colorado, in conjunction with NASA JPLand the THEMIS The team at Arizona State University in Tempe, Arizona developed procedures for rotating the spacecraft to obtain looking-up images of a comet flying near Mars. The teams have adapted those procedures to image the potato-shaped duo of Martian moons.
“We now have the ability to rotate the spacecraft to THEMIS observations. There is a greater interest in Phobos due to the possibility that future astronauts could use it as an outpost,” commented Dr. Jeffrey Plaut on October 4, 2017 JPL press release. Dr Plaut is a Project Odyssey Scientist made JPL.
With the first observation now completed, plans are being made for additional major observing opportunities at different illumination phases of Phobos Y Demos.
As Dr. Hamilton points out, “We want to get observations under all kinds of lighting: broad daylight, a small crescent, during the eclipse. We hope this is the first of several observations that will help us understand Phobos Y Demos.“