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Astronomy Picture of the Day - Small Moon Deimos
NASA ^ | 7 Sep, 2024 | Image Credit: HiRISE, MRO, LPL (U. Arizona), NASA

Posted on 09/07/2024 1:04:50 PM PDT by MtnClimber

Explanation: Mars has two tiny moons, Phobos and Deimos, named for the figures in Greek mythology Fear and Panic. Detailed surface views of smaller moon Deimos are shown in both these panels. The images were taken in 2009, by the HiRISE camera on board the Mars Reconnaissance Orbiter spacecraft, NASA's long-lived interplanetary internet satellite. The outermost of the two Martian moons, Deimos is one of the smallest known moons in the Solar System, measuring only about 15 kilometers across. Both Martian moons were discovered in 1877 by Asaph Hall, an American astronomer working at the US Naval Observatory in Washington D.C. But their existence was postulated around 1610 by Johannes Kepler, the astronomer who derived the laws of planetary motion. In this case, Kepler's prediction was not based on scientific principles, but his writings and ideas were so influential that the two Martian moons are discussed in works of fiction such as Jonathan Swift's Gulliver's Travels, written in 1726, over 150 years before their discovery.


TOPICS: Astronomy; Astronomy Picture of the Day; Science
KEYWORDS: apod; asaphhall; astronomy; deimos; gulliverstravels; johanneskepler; jonathanswift; mars; nasa; phobos; science; usno
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To: marktwain
You could throw rocks from Deimos have them fall on Mars. Hint: throw them in the direction Deimos came from.

Nope, would never work.

Or do you think that people on the I.S.S. could de-orbit simply by shoving off from the space station?

Throwing a rock as hard as you can from Deimos - in the retrograde direction - would merely place the rock into a slightly lower orbit (one with one apsis touching Deimos' orbit, and with the other apsis maybe 1 km lower).

HINT: It would take about as much energy to de-orbit from Deimos and impact on the surface of Mars as it would take to blast off from the surface of Mars and reach Deimos.

Regards,

21 posted on 09/08/2024 2:16:03 AM PDT by alexander_busek (Extraordinary claims require extraordinary evidence.)
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To: Alas Babylon!
Moving Deimos in that matter (either with or without first "coring" it) would be an extremely tricky matter - like maneuvering a "dusty bunny."

Deimos is an assemblage of dust and rubble, barely held together by its weak self-gravity.

Regards,

22 posted on 09/08/2024 2:18:37 AM PDT by alexander_busek (Extraordinary claims require extraordinary evidence.)
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To: MtnClimber

About the size of the asteroid that wiped out the dinosaurs.


23 posted on 09/09/2024 3:20:07 AM PDT by minnesota_bound (Need more money to buy everything now)
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