In my world, a scientist and engineer by the name of Guan thinks of the practicality of a vacuum airship transport and possible pitfalls.

What major Problems and Practicality issue might exist with making a Vacuum Airship?

  • $\begingroup$ It is unclear what you ask. If you want an airship (blimp of some sort) to be able to travel from Earth to Mars that's utterly impossible, of course (aerostats get their lift from the weight of surrounding air; this means you need both air and gravity pull making it "weight" in some direction). Please clarify. $\endgroup$
    – ZioByte
    Sep 2 '17 at 7:12
  • $\begingroup$ Was Mars terraformed? If so: what is atmosphere composition and pressure? Current (real) Mars atmosphere is too thin for blimps. $\endgroup$
    – ZioByte
    Sep 2 '17 at 7:54
  • $\begingroup$ As long as your envelope is positively buoyant, currently on Earth there isn't a good material which is cheap, lightweight and strong enough to withstand the enormous crushing air pressure. $\endgroup$
    – user6760
    Sep 2 '17 at 8:45
  • $\begingroup$ @JBH Your first suggested duplicate doesn't meet the requirements. Please read any possible duplicates more carefully in future. We don't want mistakes, and I'm sure you'd agree. Your second option is much more interesting. $\endgroup$
    – a4android
    Sep 2 '17 at 12:01
  • $\begingroup$ Hi, Theocles. I've removed the hard-science tag because you've added it after answers were posted, meaning that the edit would have invalidated them. Invalidating answers is frowned upon on Stack Exchange. $\endgroup$
    – HDE 226868
    Sep 2 '17 at 19:43

I would suggest to use hydrogen-filled blimps.

These would be only fractionally (~7%) less efficient than vacuum while having no structural problems.

Low Mars atmosphere density calls for huge balloons, but they would probably be feasible.

Fact Mars atmosphere does not contain sizable quantities of oxygen means mitigate a lot possible problems with hydrogen being highly flammable.

Sand storms shouldn't be a big problem as they are usually confined below 800m.

Mars has a lower atmosphere density, which means there's less pressure drop with altitude, which, in turn, means higher altitudes can be achieved with less buoyancy reserve.

If this seems acceptable we can try to compute required sizes and engine power.

  • $\begingroup$ This is entirely Acceptable. Thank you for your answer $\endgroup$
    – user15036
    Sep 3 '17 at 6:46

Dr Guan will of course be familiar with the Eighth Barsoomian Ray, long used by indigenous Martians to fill their lighter-than air craft.

The powerful source of the ray in the center of the vacuum "reservoir" emits 8th ray spectrum photons. Although technically massless (and so not interfering with the vacuum), photons have relativistic mass inversely proportional to their wavelength. https://physics.stackexchange.com/questions/2229/if-photons-have-no-mass-how-can-they-have-momentum

The excellent thing about the 8th ray is that by virtue of their relativistic mass, the photons can do work against the interior of the vacuum reservoir, keeping it "inflated" against the exterior atmospheric pressure. The special semicrystalline coating on the vacuum reservoir interior helps to make sure these 8th ray photons expend their energy there and do not penetrate on through. The back pressure from reflected rays can itself limit further emission from the source, via relativistic mass action.

On the occasional instance where the vacuum reservoir is penetrated one can see the effect of the 8th ray on the external atmosphere. If the hole is small (such as that created by small arms fire) this effect is enough to prevent atmospheric ingress until the crew can patch it. Larger gaps are dangerous because the source, no longer limited by reflective rays, will emit more radiation and so enter a runaway feed forward loop, consuming itself and the surroundings.

found at https://jrmalone.deviantart.com/art/Orbital-Hive-Updated-155620654 enter image description here