<ol>
<li><p>The gravity of those moons is so low that when and if something &quot;lands&quot; on them it will be more like two spacecraft rendezvousing and docking than like a spacecraft landing on a world.  And it hasn't been done yet.</p>
</li>
<li><p>According to this list:</p>
</li>
</ol>
<p><a href="https://en.wikipedia.org/wiki/Tidal_locking#List_of_known_tidally_locked_bodies" rel="nofollow noreferrer">https://en.wikipedia.org/wiki/Tidal_locking#List_of_known_tidally_locked_bodies</a></p>
<p>Deimos and Phobos are known to be tidally locked to Mars.</p>
<ol start="3">
<li>Phobos and Deimos both orbit Mars in the same direction, prograde, at different distances from Mars. So it takes Deimos, the farther moon, longer to make one orbit around Mars than it takes Phobos, the closer moon.</li>
</ol>
<p>So Phobos periodically passes in front of Deimos as seen from some places on the surface of Mars.  Here is a link to a video of such an event:</p>
<p><a href="https://en.wikipedia.org/wiki/Moons_of_Mars#/media/File:PIA17352-MarsMoons-PhobosPassesDeimos-RealTime.gif" rel="nofollow noreferrer">https://en.wikipedia.org/wiki/Moons_of_Mars#/media/File:PIA17352-MarsMoons-PhobosPassesDeimos-RealTime.gif</a></p>
<p>And you could have researched that easily yourself.</p>
<p><a href="https://en.wikipedia.org/wiki/Moons_of_Mars" rel="nofollow noreferrer">https://en.wikipedia.org/wiki/Moons_of_Mars</a></p>

CC BY-SA 4.0
2021-11-03T19:45:01.823Z
To add some numbers to your response, the surface gravity of Phobos is ~.05% that of the surface gravity of earth, and Deimos is about .02% of the same. Phobos and Deimos are in a 4:1 resonance, so Phobos orbits 4 times for every one time that Deimos orbits
Justin T
CC BY-SA 4.0
2021-11-03T19:22:56.233Z
2021-11-03T19:39:09.097Z
2021-11-03T19:39:09.097Z
M. A. Golding
<p>Are Phobos and Deimos tidally locked to Mars?</p>

CC BY-SA 4.0
2021-11-03T20:13:08.790Z
Hello Star girl.  There are really three different questions here. It's best to ask one question at a time.  So which question do you want answered first?  It is also best to tell us what you've done already to answer these questions.  For example, have you read the wikipedia page on Phobos and Deimos?  Have you tried google "mission to phobos"
James K
CC BY-SA 4.0
2021-11-03T20:41:07.833Z
The fact that two of the questions are answered in the wikipedia pages tempts me to downvote the question.
Jim421616
CC BY-SA 4.0
2021-11-03T20:43:49.910Z
In partial answer to the first part of the question, nobody has landed on Phobos and Deimos yet, but JAXA is sending [MMX, the Martian Moons eXplorer](https://www.mmx.jaxa.jp/en/) to explore the moons and return a sample from Phobos. Launch is due in 2024, with arrival at Mars in 2025 and sample return to Earth in 2029.
astrosnapper
<tidal-locking><phobos><deimos>
Phobos and Deimos tidal locked?
StarGirl6789
# Phobos and Deimos tidal locked?

(Asked by: username_0 on 2021-11-03)

Are Phobos and Deimos tidally locked to Mars?

**Tags:** tidal-locking, phobos, deimos
> **Comments:**
> **username_1**: Hello Star girl.  There are really three different questions here. It's best to ask one question at a time.  So which question do you want answered first?  It is also best to tell us what you've done already to answer these questions.  For example, have you read the wikipedia page on Phobos and Deimos?  Have you tried google "mission to phobos"  
> **username_2**: The fact that two of the questions are answered in the wikipedia pages tempts me to downvote the question.  
> **username_3**: In partial answer to the first part of the question, nobody has landed on Phobos and Deimos yet, but JAXA is sending [MMX, the Martian Moons eXplorer](https://www.mmx.jaxa.jp/en/) to explore the moons and return a sample from Phobos. Launch is due in 2024, with arrival at Mars in 2025 and sample return to Earth in 2029.  

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## 1 answers

### Answer by username_4 on 2021-11-03. Score: 3

1. The gravity of those moons is so low that when and if something "lands" on them it will be more like two spacecraft rendezvousing and docking than like a spacecraft landing on a world. And it hasn't been done yet.
2. According to this list:

<https://en.wikipedia.org/wiki/Tidal_locking#List_of_known_tidally_locked_bodies>

Deimos and Phobos are known to be tidally locked to Mars.

3. Phobos and Deimos both orbit Mars in the same direction, prograde, at different distances from Mars. So it takes Deimos, the farther moon, longer to make one orbit around Mars than it takes Phobos, the closer moon.

So Phobos periodically passes in front of Deimos as seen from some places on the surface of Mars. Here is a link to a video of such an event:

<https://en.wikipedia.org/wiki/Moons_of_Mars#/media/File:PIA17352-MarsMoons-PhobosPassesDeimos-RealTime.gif>

And you could have researched that easily yourself.

<https://en.wikipedia.org/wiki/Moons_of_Mars>

> **Comments:**
> **username_5**: To add some numbers to your response, the surface gravity of Phobos is ~.05% that of the surface gravity of earth, and Deimos is about .02% of the same. Phobos and Deimos are in a 4:1 resonance, so Phobos orbits 4 times for every one time that Deimos orbits  

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