Satellite rule query

[SANEAlex]

Hi Paul i just want to check on the rules about the Satellite it says that parts of the Launch vehicle can go into orbit with the Satellite but must but must not be attached to the 19.99 gram Satellite

My questions is would it be ok if the Satellite was enclosed within the remains of the launch vehicle if it was bouncing around free within it and not electrically or physically attached to the remains.

An example of what i am thinking would be if we had a hollow foam ball to protect the satellite by surrounding it on launch etc but once in orbit the satellite would be floating free in the middle of the ball if it was a transmitter the detection would be by radio so the ball would not be helping in detection or providing power to the satellite would this be ok.?

[pauldear]

Hi Alex,

Sorry for the slow reply - I've been away and am just back.

I think having the satellite enclosed would be stretching the rules, I'm afraid, free-floating or not. Is there any way you could have the shell split open? Even if it were nudged away by a spring or two, that would do.

How's things? We ought to get together for an N-Prize gathering again, and I'm (still!) hoping to organise a small-space conference with a good representation from the N-Prize teams.

Best,
Paul

[SANEAlex]

[pauldear]

Try-to-do-the-impossible plans are definitely the way to go. A realistic schedule can only fall behind; an impossible one brings out the best! Go for it.

[pauldear]

On a similar note, a team recently asked me if an N-Prize satellite could communicate via a co-orbiting larger satellite (basically acting as a "relay").

The answer is no - the N-Prize satellite has to be capable of "standalone" communication, or at least tracking.

Of course, if your final-stage-rocket winds up co-orbiting with the satellite (as long as it's physically separated), you could start by tracking that final stage (which might be easier to find), and then use that information to tell you where to look to track/communicate with your N-Prize satellite. But the N-Prize sat itself has to be trackable independently during its qualifying orbits.

[WillD]

thought as much
that's how i've got ours configured. more powerful transmitter in the co-orbiting payload and the actual n-prize sat having the smaller mass & power - but is itself separate.

[DaveHein]

Of course, the main problem with a co-orbiting satellite is the extra mass you would have to put into orbit. If your co-orbiting satellite is significantly larger than the N-Prize satellite you will need a larger rocket to get it into orbit. With a 20-gram payload the final stage could be on the order of an F or G power hobby motor if the rest of the final stage is light enough. This would require the motor casing to have a mass about the same as the satellite. The satellite can be seperated from the final stage with a tiny amount of black powder that is ignited after the motor burns out, similar to the way a hobby motor fires its ejection charge.

All the other rocket stages will scale by the mass of the final stage. If you include a 100 gram co-orbiting satellite you would need a rocket that is 6 times larger than one that only orbits a 20-gram satellite. A 20-gram satellite is very small, but with good power management you could broadcast a sufficiently strong radio signal for 14 hours.

Dave

[Monroe]

Dave
The satellite release from the final stage is going to be a delicate maneuver! If it's spinning and tumbling too fast it will not transmit a good signal. Over heating is going to be a big issue and there's a lot of other factors. Black powder is useless in space. It's going to be a little more complicated than that fellas. Getting a good orbit with a tiny satellite will be no small feet.

Monroe

[rick m]

In the vacuum tests we've done, if you design it properly, black powder will work but there are better choices. Some other methods that we have been investigating and testing would reduce the mass of the final stage and eliminate the need for any additional separation device (mass). A lot of this has to do with characterizing our new propellant sufficiently to avoid the unplanned CATOs that have plagued our testing with this propellant so far...

[DaveHein]

Monroe, I don't think black powder is useless in space -- it just requires good ignition and containment. If it is contained properly there will be a sufficient amount of gas to transfer heat to the surrounding particles to maintain combustion.

Rick even with a very light motor casing, it still seems like you would need to separate the satellite from the final stage to meet the 20 gram limit. It will be hard enough to package a transmitter and battery that will weigh less than 20 grams. I can't imagine how a motor casing could be included in that mass budget.