119
votes
Can a human land on Deimos using pressurized deodorant cans?
Deimos: radius 6.2km, mass 1.47 $\cdot$ 1015kg.
Let's pick an initial circular orbit radius at a safe 8km.
Orbital velocity calculator gives 3.502m/s orbital velocity.
To deorbit, we'd need to drop ...
- 54.9k
34
votes
Accepted
Could a Mars rover go to Phobos or Deimos instead?
No, for a lot of reasons.
The Mars rovers slow down based on aerodynamics, heat shields, and parachutes. None of that is available on one of the Moons, meaning that the fuel requirements are much ...
- 121k
14
votes
Accepted
Can a human land on Deimos using pressurized deodorant cans?
I don't think you would get any significant thrust from them on Deimos.
The maximum surface temperature is -4 °C (source).
The boiling point of butane is -2 °C (source).
I don't think the can would ...
- 356
12
votes
Accepted
What modifications would be necessary to make to a Mars rover to let it land on Phobos or Deimos?
The very low gravity would require a total redesign. Phobos is the larger body and has a surface gravity of around 0.6 milli-g, or around 1500 times less than here on Earth. The newest rover, ...
- 995
12
votes
Accepted
Venus-Mars-Venus cycler?
Is it possible to create a cycler that can travel from Venus to Mars, then back to Venus?
Yes. When only two planets are involved, there are several infinite families of cycler orbits.
Given the 434 ...
12
votes
Accepted
Can you ride a bicycle on Deimos?
At that surface gravity, I don't see how it would be possible to ride a bicycle. The friction between the tires and the road is how the motion of the wheels is converted to motion of the bicycle and ...
- 167k
9
votes
Can you ride a bicycle on Deimos?
Yes, with suitable modifications.
The loop must be ferrous. Your bike needs strong magnets in the wheels. You will start out with low friction and have to pedal very gently but as you build up your ...
- 11.5k
8
votes
What modifications would be necessary to make to a Mars rover to let it land on Phobos or Deimos?
A partial list of subsystems that would need to be redesigned:
Since the gravity is low, there's a high chance that you will flip over at some point. You will need to ensure that you can flip back, ...
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4
votes
How do you find ZRVTOs between tethers from coplanar, tidelocked bodies?
Yes. Given the radii of the upper and lower moons and knowing their angular velocities, there are simple expressions that give the periapsis and apoapsis radius of the Zero Relative Velocity Transfer ...
- 15.6k
3
votes
Calculating low-thrust capture delta-V with high $V_{inf}$
It sounds like the Red Dragon is relying on aerobraking to exit the Hohmann transfer ellipse and soft land on Mars. I don't think the cube sat would want to use aerobraking to shed velocity. For one ...
- 15.6k
3
votes
Could a Mars rover go to Phobos or Deimos instead?
The skycranes don't throttle enough, a landing is impossible.
I note objections based on the EDL systems not having the delta-v to do it. This is a high hurdle but not actually a complete showstopper. ...
- 11.5k
2
votes
Is there any footage from Mars where you can see Deimos or Phobos getting bigger and smaller as it goes through the sky?
The longest timelapse of a Martian moon I'm aware of is this 27 minute long timelapse of Phobos rising at June 28, 2013.
The light conditions, and the relatively small ...
2
votes
What delta-v is required to move between Phobos and Deimos?
I'm sure others will provide Hohmann numbers, but if you happen to be using low-thrust propulsion that requires spiraling down, the delta-v approximately equals the difference in Phobos and Deimos's ...
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1
vote
Calculating low-thrust capture delta-V with high $V_{inf}$
Mars SOI radius: 576,000km src
Mars escape velocity: 5.03 km/s src
You're coming in at 6km/s so you need to shed 1km/s to capture. At 1mm/s^2 that's 1mln seconds, or some 11 days.
In 1mln seconds, ...
- 54.9k
1
vote
Calculating low-thrust capture delta-V with high $V_{inf}$
Disclaimer: I am not sure I understand your problem, so let me know if I misunderstood and I'll edit my answer.
The main problem with low thrust engines is that they are ... low thrust: you'll need ...
- 6,200
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