![]() ![]() This article was most recently revised and updated by Robert Lewis. If such is the case, it will collide with Mars in the very distant future. Precise observations of Phobos’s position over the past century suggest that tidal forces from Mars are slowly pulling the satellite toward the planet. This structure, known as Stickney, measures about 10 km (6 miles) across. There is strong evidence that they are associated with the formation of the largest crater on Phobos. Remarkable linear grooves, typically 100 metres (330 feet) wide and 20 metres (65 feet) deep, cover much of the surface. This fact and the satellite’s low mean density (1.9 grams per cubic cm) are consistent with the composition of carbonaceous chondrite meteorites, suggesting that Phobos may be a captured asteroid-like object. The heavily cratered surface of Phobos is covered with a very dark gray regolith (unconsolidated rocky debris) that reflects only about 6 percent of the light falling on it-about one-half that of the Moon’s surface. Learn about Phobos and Deimos, Mars's two tiny moons See all videos for this article SpaceNext50 Britannica presents SpaceNext50, From the race to the Moon to space stewardship, we explore a wide range of subjects that feed our curiosity about space!.Learn about the major environmental problems facing our planet and what can be done about them! Saving Earth Britannica Presents Earth’s To-Do List for the 21st Century.Britannica Beyond We’ve created a new place where questions are at the center of learning.100 Women Britannica celebrates the centennial of the Nineteenth Amendment, highlighting suffragists and history-making politicians.COVID-19 Portal While this global health crisis continues to evolve, it can be useful to look to past pandemics to better understand how to respond today.Student Portal Britannica is the ultimate student resource for key school subjects like history, government, literature, and more.This Time in History In these videos, find out what happened this month (or any month!) in history.#WTFact Videos In #WTFact Britannica shares some of the most bizarre facts we can find.Demystified Videos In Demystified, Britannica has all the answers to your burning questions.Britannica Explains In these videos, Britannica explains a variety of topics and answers frequently asked questions.Britannica Classics Check out these retro videos from Encyclopedia Britannica’s archives.Their orbits are nearly circular and they both can transit the Sun. How fast do the two moons move relative to each other when viewed from Mars?įigure 2 is a good graphic that illustrates how Phobos and Deimos move about Mars. ![]() How large are Phobos and Deimos as seen from Mars compared to the Moon when seen from Earth?. ![]() Thus, my reading has made me interested in two questions about Mars and its moons. I also cannot believe that they appear to be very large in the sky. I can believe that Phobos moves across the martian sky pretty fast, but I am not sure about the movement of Deimos. So I thought a few calculations would be in order. I started to wonder if these characteristics were true. the nearer moon of Barsoom raced through the western sky toward the horizon. (Phobos orbits just 5,826 miles, or 9,376 km, from the Red Planet on average. He also commented on Phobos' speed across the sky with this statement. Or they could be strain marks showing that Mars' gravity is tearing Phobos apart. The nights are either brilliantly illumined or very dark, for if neither of the two moons of Mars happen to be in the sky almost total darkness results, since the lack of atmosphere, or, rather, the very thin atmosphere, fails to diffuse the starlight to any great extent on the other hand, if both of the moons are in the heavens at night the surface of the ground is brightly illuminated. But since Phoboss orbital radius is only 2 or 3 times the radius of Mars, phases of Phobos look different from different spots on Mars. In "A Princess of Mars", Burroughs describes the moons of Mars, Phobos (Figure 1) and Deimos, as being large and very bright at night. I downloaded the audio book from Libravox, which provides free downloads of readings from classic works. Normally, I do not listen to much science fiction, but I watched the movie " John Carter" and there was something I liked about the story. I am listening to the audio book "A Princess of Mars" by Edgar Rice Burroughs. As a result, the rocks on the near side of Phobos have been bathed for millennia in Martian atoms and molecules. The thought of alien worlds with multiple moons has always intrigued me. Phobos is tidally locked to Mars, like Earth’s moon is locked to Earth, thus always showing the planet only one side. ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |