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I'm wondering if it'd be possible to tape a bottle rocket to one of these chipsat things and carry it to space with a balloon. Once the balloon hits max altitude, the small rocket is ignited and takes the chipsat into space.

Feasible? Stupid? Are there much easier/better ways to get a chipsat into space? Are there laws against doing such a thing?

Update After doing further research on it I've discovered this is one of the stupidest questions I've ever asked.

PearsonArtPhoto
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corysimmons
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    Its not such a bad question from the perspective that everyone has to start somewhere in their comprehension of the problem. The fact that you have asked it at least shows some curiosity so I hope this gives you some momentum to read around it - there are questions that relate to the same fundamental problem of energy here already such as http://space.stackexchange.com/questions/10803/is-it-possible-to-reach-space-using-home-made-rocket?rq=1 - have a nose around the "related questions" area too. – Puffin Jan 13 '16 at 00:23

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You can get things to the edge of space with a balloon fairly easily (in fact quite a few people have done this as amateur science projects) but getting into a stable orbit is an entirely different matter as a low earth orbit requires a relative velocity of something like 7km/s. In fact for a conventional rocket the energy to achieve the altitude to get into space is a fairly small fraction of that required to accelerate to the orbital velocity needed to stay there.

Chris Johns
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  • Near Earth space is not a total vacuum. Couldn't in principle a large enough sphere made out of light and strong enough material contain a perfect vacuum and thus become lighter than space and "anti-gravitationally" float up into it? No need for any escape velocities then. – LocalFluff Jan 13 '16 at 04:50
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    @LocalFluff I did no math on this but my guess is that even having the balloon thickness lowered to 1 molecule would give you the average density of baloon envelope+contained vacuum much higher that the vacuum itself - theoretically you could make the balloon really big to get small enough surface-volume ratio, but that would be really huge. And thats not accounting for the reality that a balloon is kept in its shape by the pressure of the gas inside, whereas vacuum does offer no support so you would have to give it some internal structure too, to not be deflated. – jkavalik Jan 13 '16 at 07:34
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    @LocalFluff https://i.ytimg.com/vi/Zz95_VvTxZM/hqdefault.jpg - this was metal with low pressure inside. – jkavalik Jan 13 '16 at 07:35
  • Escape velocity is a different thing to orbital velocity. Escape velocity is the kinetic energy an object needs to counteract its gravitational potential energy. Orbital velocity at a given altitude doesn't actually overcome gravity but rather establishes a stable equilibrium as a given distance from the earth's centre of mass. The energy required to work against gravity to get to low earth orbit is actually fairly small. – Chris Johns Jan 13 '16 at 21:55
  • @ChrisJohns Fairly small? LEO requires about 7.8 km/s, escape velocity from Earth's surface is about 11.2 km/s. If you do the math, energy to achieve LEO is about half that to attain escape velocity. I think the key point in relation to the OP's question is that simply going vertical to space to just fall straight back down is relatively easy (~1 km/s) when compared to attaining LEO (about 60x the energy). If you can get to LEO, you're at least in the ballpark when compared to escaping Earth altogether (if factor of two is "in the ballpark"). – Anthony X Oct 11 '16 at 02:01