# Building a ultra-small almost space vehicle

I'm quite interested in small rockets-balloons that can reach more than 50km, thus I want to build one myself (With my school financial support). I just want it to carry like a 350g-450g equipment. My aim is to make some really high quality footage up in there. I (almost) get that a meteorological balloon would be quite ideal, but still, it just wouldn't be original to vindicate the investment. That said is it even possible to make it for under 600 dollars?

I'm also not sure about the availability of the things since I live in the central Europe

You will have quite a challenge to get to 50 km with a balloon or reasonable sized rocket. Even weather balloons don't hit those altitudes. Probably one of the best places to start for this kind of information is the Amateur Radio High Altitude Ballooning page. In particular, check out their "How To PowerPoints" section.

For what you want to do, there is a good deal of info out there to start with. If you really want to go for altitude, people have launched rockets from balloons, which are often called "Rockoons". But even so, for a rocket that has enough thrust to get to thousands of feet, those end up being pretty big, so they are harder to lift with a balloon.

• Good advice! In the video linked in this question you can see NASA used a large balloon to get to ~36km, then as you mention, a rocket was used to get to ~55km from there. Just fyi there is a stackexchange for hams as well: ham.stackexchange.com – uhoh Mar 23 '17 at 13:47

Yes it is possible, no it won't be easy.

You might already know this, but the higher you go the thinner the atmosphere gets. The higher you want to go the bigger/and or lighter you need to make the balloon.

Breaching 50km has been done. I don't know if you can do it for under 600, given current materials. If you're interested, here's a wiki article that discusses high altitude balloons https://en.m.wikipedia.org/wiki/High-altitude_balloon

It also mentions BU60-1 as a balloon that reached 53km. Check it out for ideas.

• Atmospheric pressure at 50km is about .119 kg/square meter. You need to make a balloon that can reliably maintain (for my own lack of technical terms) an average "pressure" of less than or equal to that to reach 50km, after adjusting for all cargo. Anyone here want to help me put this into technical terms? – Nomadyn Mar 23 '17 at 12:05
• Can you translate that pressure into more reasonable units? I don't know if balloonists use $kg/m^2$ for pressure, but rocketologists certainly don't! – uhoh Mar 23 '17 at 13:42