i know

it's crazy

but let's say i wanted to put my basketball, or something of similar weight/dimension into orbit using a 2 part propulsion system to get there. the first part would boost the second into space before detaching and vanishing as it re-enters orbit, the second part would be a capsule holding the ball inside that can navigate from space into orbit and then collapse itself leaving only the ball in orbit.

hence the basketball in orbit

now, how heavy and big would you imagine a device like this would be?

the only source of information i found that could answer my questions is this one:
http://world.std.com/~swmcd/steven/stories/orbit.html

do you know any others?

This idea is first place science fair status.

Now, I know that you are not serious about this, but it's an interesting thought exercise

you'd need a big, multi-stage solid fuel rocket. Liquid fuel is way too complicated for an amateur. Anyways, you'd have to launch it in the desert. Southwest US would be a good launch location. You could figure out fairly easily the amount of thrust you'd need, and with some basic experimenting, you could calculate the size and number of stages. I don't think any amateur has ever done this, though.

hmm, indeed, this is a nice thought exercise - I don't think i would ever go through building this device, but i would seriously enjoy making it possible.

I do agree a solid fuel rocket would be necessary, but the process of getting into orbit is a bit tricky. the site i posted earlier says that i need to to have 32million joules (or mega joules?) per kilogram to enter orbit from space and for some reason, i believe there is some tricky manoeuvring to do that process.

It would be necessary to consider which stages have been removed from the rocket at this stage in space and how much the unit would weigh to get a correct estimate of the amount of power it takes to put something into orbit once it is in space.

if any one has more documentation on this kind of stuff, feel free to post.

You should do some more research. That's a pretty crappy website. Research the rockets of the space race. And also look up solid-fuel rockets. You'll need to look up some engineering to figure out how much energy you need. http://en.wikipedia.org/wiki/Geocentric_orbit 1 MJ/kg looks like it's a fairly good approximation for the energy you'll need. You can verify this by integrating the work needed to bring something from the earth's surface to the border of space, plus the air resistance and inefficiencies of the rocket and such.

The easiest way to do it is make a modular big fuckin' rocket enigine, test how much energy you get out of it, then figure out how many stages you need.

I'd suggest a large hydrogen balloon for the first stage. Hydrogen balloons are capable of reaching up to 20 kilometers in altitude.

This could be used as a rocket platform, saving heaps of rocket fuel by launching from 20 000 meters rather than ground level. One cubic meter of hydrogen displaces more than a kilogram of air, so a rectangular balloon that was 3m x 3m x 15m would have a lifting capacity of 135 kilograms. Subtracting 35 kilograms for the weight of the balloon and launch platform would be reasonable, leaving 100kg for your payload. A 100kg liquid-fueled sounding rocket would be able to reach orbit from that height easily enough.

indeed, this sounds compelling.

But i still have to reach at least 80km with liquid fuel, and with this setup, i have a 100kg payload limit. Time to do some googleing. 80km in 100kg.

http://sites.wff.nasa.gov/code810/technologydevelopment.html

I can't find a weight listing for it, but it's pretty small. Remember, you don't have to fly to 100km under power, you just need to get about 60 or 70km and at that speed, your payload will coast the rest of the way.

http://www.astronautix.com/lvs/loki.htm
I particularly like this one:

PWN-1A:

Length (incl. booster):
2.63 m (8 ft 7.5 in); dart: 1.02 m (40 in)
Diameter Booster:
7.62 cm (3 in); dart: 3.49 cm (1.375 in)
Finspan Booster:
12.7 cm (5 in); dart: 8.6 cm (3.4 in)
Weight (incl. booster):
13 kg (29 lb); dart: 3.2 kg (7 lb)
Speed:
6275 km/h (3900 mph)
Ceiling:
55 km (34 miles; 180000 ft)
Propulsion:
JPL 132A solid-fuel rocket; 9.0 kN (2030 lb) for 1.9 s

damn, this loki dart is exactly the setup we are talking about. the size is pretty good as well.

i see 3 problems 2 of which are related.
1. apogee is only 75 km. this is not orbit. it is barely even space.
2. this is the propulsion system used by the loki pwn-1a: JPL 132A solid-fuel rocket; 9.0 kN (2030 lb) for 1.9 s
3. this rocket can barely get me a baseball in space. it's gonna have to be 4 times wider.

now, i'm not sure what that is, but it's now what they use for shuttle launches which is, as i understand it, ammonium perchlorate as an oxidant to aluminum powder(APCP Ammonium perchlorate composite propellants) or magnesium powder with ammonium nitrate as an oxidizer.

http://en.wikipedia.org/wiki/APCP
(that article also suggests that lift powder, which is compressed black powder, will not do at all)

either one of those 2 solid fuels are good and will probably yield a better apogee than what ever "JPL 132-A for 1.9s" is. in probably less time too.

let's dwell on that a bit

whoops,

looks like the _super_ loki has apogee of something like 115km
specs are as follows:

Note: Data given by several sources show slight variations. Figures given below may therefore be inaccurate!

Data for PWN-12A:
Length (incl. booster) 3.16 m (10 ft 4.5 in); dart: 1.16 m (45.7 in)
Diameter Booster: 10.2 cm (4 in); dart: 4.0 cm (1.58 in)
Finspan Booster: 20.3 cm (8 in); dart: 11.7 cm (4.62 in)
Weight ?
Speed ?
Ceiling 115 km (70 miles; 380000 ft)
Propulsion Aero Dyne SR110-AD-1 Super Loki solid-fuel rocket; 25 kN (5520 lb) for 2.1 s


the problem is, weight is actually important to us....
/sigh

EDIT: i realize that launching off a balloon means the rocket doesn't have to hit 100km in height, but it does have to reach 80 and the first loki only does 75.

Easy Pay the Russians to do it.:p

Otherwise I like the balloon idea, it seems very economical in terms of fuel savings, however I think it would be difficult to design a launch platform that didn't have the rocket going strati thought the balloon above it... Three balloons set up in a triangle and connected by struts with the rocket in the center of the triangle on a platform may be a solution.

And interms of rocket fuel, why not some thing exotic like a metal and peroxide mix (granted it wold be very dangerous), mabe even a metal peroxide???

stability is for sure the biggest issue when it comes to the balloon. I like the triangle idea because then i can make a simple mechanism on rails to shift weight from one part of the triangle to another and that would keep the platform leveled. good thinking

as for the fuel, i don't enough about solid or liquid fuel types to determine how to make good or bad fuel. that is the problem. maybe someone can point us in a direction with this.

This is an interesting idea.

I would search the web for some model rocket clubs, and post it to a forum there, also.

One of the contractors from my office is a model rocket hobbyist, and he claims that they have launched a rocket into near-earth orbit(NEO).

I know that they only launch a few times a year, because they have to have the airspace within a certain window cleared of air traffic while they are launching.

This includes airliners, so if they are clearing that high of a ceiling, then they must be getting some altitude.

Usually the people who launch are very tech and detail oriented, so they would probably have a field day with it.

I am no science major but I see 2 problems....

Heat on the ball

and would the air trapped on the inside of the ball be an issue?

A 100kg liquid-fueled sounding rocket would be able to reach orbit from that height easily enough.

By that stretch, what if one accidentally launches it beyond orbit, and into deep space?