Using Sails to Deorbit Satellites

[ozone]

Interesting Idea
http://news.bbc.co.uk/2/hi/science/nature/8029899.stm

 

[Andy44]

For the mass of a aerosail, you could put a small rocket motor on a satellite and deorbit in a more timely and controlled manner.

For boosters, I didn't know we were still leaving upper stages in orbit these days. All this concern over space junk has been around since at least the 80s, and I know that many boosters do deorbit themselves. Yes, you need restartable jets, but restartable jets are desirable for orbit insertion maneuvers anyway.

I guess you'd have to do a trade study about whether the mass of the extra prop needed to deorbit a given stage is less trouble than the mass, complexity, and bulkiness of an aerosail system.

You also have to study the benefits of leaving an aerosail-equipped booster in orbit for as many as 25 years, complete with the increased collision hazard of a large-area sail, vs. the benefits of a powered deorbit.

You also have to study the risks vs. benefits of funding such a system's development. Will you have to spash out zillions of dollars/euros for a questionable return?

This would be a cool systems engineering problem to work on.

 

[eveningsky339]

Has a functional "sail vessel" of any kind been put into orbit before? This could certainly save expensive propellant and mass.

 

[RisingFury]

I don't think this is a good idea. You can't predict the drag nicely due to unpredicted solar activity. You wouldn't want it reentering over a heavily populated area...

 

[Andy44]

Well, as they are currently launching them, their eventual reentries cannot be predicted or controlled, so how is this any worse? Remember the Russian booster that streaked in over Denver a few months back? That could've caused an accident, but the chances of anyone actually getting hit by one of these thngs' parts is minscule, and that "big surface, little pieces" theory is what drives the current modus operandi.

 

[Wolfer]

There's so little air up there that it's impossible to get a nice flow. Wouldn't that mean that the spacecraft would still spin in all direction, unless the sail was impracticaly huge?

 

[Bj]

Seems like an ok concept in theory, but I think really impractical. For one, you will need to get the sail up to the satellite. As long as you have a engine being launched up there, why not use the engine to quickly deorbit the satellite? :hmm:

 

[Andy44]

Well, I think they're talking about future satellites. And some satellites are designed without propulsion systems for various reasons. Hubble has no propellants because of, among other things, post-Challenger STS restrictions. At its altitude, it doesn't need them; it controls its attitude with wheels and used mag torquers to dump momentum buildup. Other satellites have no propulsion in order to save money and weight.

Adding an aerosail adds mass, of course, but it's not a hazard like hypergolic propellants so it may prove to be cheaper. Personally, I prefer rockets.

 

[SiberianTiger]

For me, the technology of causing the front-facing surface of junk particles to evaporate (and therefore cause a deceleration momemtum) under a focused laser beam shot from a ground installation seems much more realistic.

1st - it does not require any modifications on satellites

2nd - it works on any kind of LEO junk, the less dense the more effective

3rd - the military will find the idea sweet and will really clunk some money

 

[Keatah]

lasers will never happen due to international politics..

 

[Eagle]

lasers will never happen due to international politics..

ASAT lasers are a reality and more powerful lasers are in active development.