Facts about Deimos

1. 08

   During the 1998 Pathfinder mission data analysis, scientists determined that Deimos's orbit is gradually decaying at approximately 0.002 meters per century due to atmospheric drag from Mars's upper atmosphere.

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2. 07

   Tidal forces will eventually tear Deimos apart in approximately 30 to 50 million years as it spirals closer to Mars's Roche limit.

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3. 06

   Deimos orbits Mars in a synchronous rotation pattern, keeping the same face toward the planet at all times, similar to Earth's Moon relative to our planet.

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4. 05

   Spectroscopic analysis reveals Deimos's surface composition is similar to carbonaceous chondrite meteorites, suggesting a captured asteroid origin rather than formation around Mars.

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5. 04

   A cratered, potato-shaped body, Deimos reflects only 25 percent of sunlight that strikes its surface, making it one of the darkest objects in our solar system.

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6. 03

   Measuring just 12.4 kilometers across at its widest point, Deimos is so small that its gravity could be escaped by jumping, with an escape velocity of only 5.3 meters per second.

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7. 02

   Deimos takes approximately 30.3 hours to orbit Mars, making it the slowest-orbiting moon in the solar system relative to its parent planet's rotation.

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8. 01

   In 1877, Asaph Hall discovered Mars's smaller moon Deimos, which orbits at 23,463 kilometers from the planet's center.

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