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I saw a high altitude jump where someone had exceeded the speed of sound before the air slowed him down enough to deploy a parachute. While inflated in space could a blimp enter the atmosphere while gradually increasing air pressure not to collapse from increased air pressure while descending to allow a soft non retrorocket landing?

Since the air on Mars is carbon dioxide mostly and 1% of Earth's atmosphere could a hard body blimp use the atmosphere to slow and land like the space shuttle or glider?

Yes it would not be a blimp anymore on Mars but a glider.

It would change shape and size for higher speeds to use the lift of the wing to over the buoyancy of the helium. I added the ship from the movie Flight of the Navigator because it was a good example of a blimp shaped ship changing shape for different purposes.

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    $\begingroup$ space.stackexchange.com/q/19051 @Jen please don't cross post all over the place $\endgroup$
    – agentp
    Commented Nov 19, 2016 at 16:14
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    $\begingroup$ @Muze - You need to work on the concept that once a question has been asked and it has received answers then you can't materially change the question. Your edit that I rolled back materially changed the question as it invalidated the top voted answer on this question. $\endgroup$
    – user16
    Commented Apr 20, 2018 at 11:41
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    $\begingroup$ In and of itself, cross-posting is not grounds to close a question. And it is possible to ask closely related questions tailored to the expertise of a given site. This is marginally on-topic for this site, but it could be argued that it is too broad to be meaningfully answered beyond the existing answers that request additional requirements. $\endgroup$
    – user16
    Commented Sep 22, 2018 at 13:43
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    $\begingroup$ One of the bad things about your questions - here and on other SE sites - is the excessive use of pictures and animated gifs that add nothing to the question. $\endgroup$
    – Ward - Trying Codidact
    Commented Sep 25, 2018 at 4:48
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    $\begingroup$ I rolled back the recent edits to the question. They drastically changed the question and invalidated answers. You have already been warned not to do that. $\endgroup$
    – hazzey ♦
    Commented Sep 25, 2018 at 18:20

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Q: Can a blimp enter Mar's atmosphere at the orbital speeds or faster as a glider?

A: No.

A glider relies upon upward lift force in order to avoid crashing into the ground.

For simplicity's sake, Earth's air density at sea level is 1.225 kg/m3. Mars's air density is much less than that amount at 0.020 kg/m3.

Lift force is directly related to density. So an atmosphere that has a fraction of the density of Earth's atmosphere is going to have a proportionately lower amount of lift force available.

Stated a bit more empirically - there's effectively no atmosphere for the wings of the glider to press against, so there's no lift force.

On a slightly more positive note, Mars's gravity is 38% that of the Earth's. So the glider won't accelerate as fast towards the surface of Mars as it crashes down.

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  • $\begingroup$ At mach 20 there should be enough wind to wing passing the wing to create lift no? $\endgroup$
    – user4139
    Commented Sep 23, 2018 at 1:56
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    $\begingroup$ @Muze - lift force is proportional to velocity squared, but you're still missing the fact that the density is 0.02, which will knock any result way down. Rounded to the tenth, it's effectively 0. And you also need to account for the fact that a glider can't just instantaneously stop after going mach 20. What's going to happen to the glider as the velocity decreases and there's no atmospheric density to help provide lift? $\endgroup$
    – user16
    Commented Sep 23, 2018 at 12:44
  • $\begingroup$ Yes this is becoming off topic but the atmospheric density would be high enough to create lift at Mach 20+ but would it burn up at that speed? Nasa made some inflatable heat shields and I'm wandering if it can me used on a blimp to divert air around it? At what point would surface area to weight help slow the ship? Retro rockets could be used to land it. The size of it would serve as a good starter bio dome. $\endgroup$
    – user4139
    Commented Sep 23, 2018 at 14:56
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I assume that the person you are referring to is Felix Baumgartner, who achieved a maximum speed of Mach 1.25. While this speed is very fast, this is nowhere near the speeds achieved by meteorites, satellites, or various space junk. The space shuttle, when it was in operation, reentered the atmosphere between Mach 10 to Mach 25, which would destroy both Felix, and your blimp.(1)

But to answer your question, I think you may need to look into your question a little more. When you say re-enter, is that really what you mean? Is the blimp coming from outer space and going to Earth? From what altitude? It sounds like it isn't really in space if it used its Helium to get up there. This is the case in the Red Bull Stratos jump, where the capsule reached an altitude of 38.9 km (stratosphere). Space can loosely be argued to start at the Karman line (100km)(2).

This, honestly, seems like the exchange to put this type of question. In my Aerospace Engineering undergrad, we dealt with a few problems where we ran calculations for balloons in the upper atmosphere.

Anyhow, if you are seeking further information on this subject, I would recommend looking into this subject more yourself. Do some research, and understand the subject better, so you can ask better questions. Then awesome people at stack exchange can give better answers!

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It depends on the altitude it is dropped from, the aerodynamic drag of the blimp and the fact that the atmosphere rotates with the Earth.

What I'm trying to say is that you would have to do some calculations to figure out the answer to your question.

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    $\begingroup$ This would be better as a comment $\endgroup$
    – Jonathan R Swift
    Commented Sep 24, 2018 at 9:40

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