Newfangled space-propulsion technology could help clean up Earth orbit

Apr 11, 2012 By Vince Stricherz
In this artist’s conception, a magnetized beam of ionized plasma is applied to a spacecraft headed on an interplanetary journey. The same technology could be used to remove dead satellites and other debris from Earth orbit. Credit: University of Washington

(Phys.org) -- Some of the most valuable “real estate” for humans isn’t on Earth at all but rather above the planet’s atmosphere, where all manner of human-made objects orbit. The problem is that those orbits are too crowded with dead satellites and debris, making new launches riskier.

Robert Winglee has spent years developing a magnetized ion plasma system to propel a spacecraft at ultra-high speeds, making it possible to travel to Mars and return to Earth in as little time as 90 days. The problem is that cost and other issues have dampened the desire to send astronauts to Mars or any other planet.

But Winglee, who heads the University of Washington’s Earth and Sciences Department, believes his problem might actually be a solution to the problem of space junk crowding the orbital paths around Earth.

A magnetized-beam plasma device (mag-beam for short) in Earth orbit would be able to use a focused ion stream to push dead satellites and other debris toward Earth’s atmosphere, where they would mostly burn up on re-entry. The idea has drawn interest, and some funding, from the U.S. Defense Department.

“Our proposal was that we could mitigate a whole region of space rather than work with individual pieces one at a time,” Winglee said.

As a propulsion method, mag-beam would interact with a specialized receptor on a spacecraft, pushing it to speeds perhaps greater than 18,000 miles per hour. Satellites orbiting Earth don’t have those specialized receptors, but Winglee said applying the beam directly to the satellite would still provide enough momentum to move a satellite toward the atmosphere.

A geosynchronous orbit, one in which a satellite returns to the same position above the Earth each day, “is very valuable space, but it’s full of dead satellites,” he said. For decades, communications satellites have been placed in orbits from hundreds of miles to several thousand miles above sea level to create a fixed point in the sky for ground installations to communicate with satellites. Many of those satellites have ceased to function, though they continue in their orbits.

That might not sound like such a big problem, but as space gets more crowded with gadgets, the chance of a collision between two satellites becomes even greater. Then, instead of two larger objects to worry about, satellites worth vast sums of money – and perhaps even space vehicles such as the International Space Station – would have to navigate through a cloud of debris. Even a tiny washer or screw traveling at 6,700 miles per hour in could cause serious damage to another object.

Using a mag-beam to clean up the debris is feasible now, Winglee said, and could be accomplished through a standard satellite mission costing perhaps $300 million.

The technology would not be useful for pushing near-Earth asteroids or comets away from the planet, he said, because they have too much mass for the mag-beam to be effective.

Meanwhile, Winglee and his students continue research in his Johnson Hall laboratory on the possibility of placing mag-beam units in orbit around Earth and around a planet such as Mars that humans might want to explore. With a unit on each end – one to give a spacecraft a high-velocity push on its journey and the other to slow it at its destination – a mission to Mars could be accomplished in as little as 90 days, rather than the 2.5 years it would take with conventional means.

“We’re continuing on a shoestring budget, and we’re modeling what the system can do over longer distances,” Winglee said.

Explore further: MAVEN Mars spacecraft to begin orbit of Red Planet

Related Stories

NASA proposes laser use to move space junk

Mar 18, 2011

(PhysOrg.com) -- A team of scientists led by NASA space scientist James Mason have proposed the idea of using a mid-powered laser and telescope to nudge pieces of space junk out of the way and slow it down ...

Swiss craft janitor satellites to grab space junk

Feb 15, 2012

The tidy Swiss want to clean up space. Swiss scientists said Wednesday they plan to launch a "janitor satellite" specially designed to get rid of orbiting debris known as space junk.

Russia wants to build 'Sweeper' to clean up space debris

Nov 30, 2010

Russia is looking to build a $2 billion orbital "pod" that would sweep up satellite debris from space around the Earth. According to a post on the Russian Federal Space Agency, Roscosmos' Facebook site, (which ...

Swiss satellite to tackle space debris (w/ video)

Feb 16, 2012

(PhysOrg.com) -- The proliferation of debris orbiting the Earth – primarily jettisoned rocket and satellite components – is an increasingly pressing problem for spacecraft, and it can generate huge ...

Recommended for you

Internet moguls Musk, Bezos shake up US space race

Sep 20, 2014

The space race to end America's reliance on Russia escalated this week with a multibillion dollar NASA award for SpaceX's Elon Musk and an unexpected joint venture for Blue Origin's Jeff Bezos.

User comments : 13

Adjust slider to filter visible comments by rank

Display comments: newest first

Telekinetic
5 / 5 (1) Apr 11, 2012
"...where they would mostly burn up on re-entry."

Mostly?
sender
not rated yet Apr 11, 2012
Also a means of holding a space fountain system.
antialias_physorg
5 / 5 (6) Apr 11, 2012
Mostly?

Depending on size and build. Some parts of a sattelite are very resistant to temperatures and can survive reentry (e.g. the hot parts of on-board propulsion systems).

Also a means of holding a space fountain system.
Probably much too weak for that. However, it could be a means of occasionally boosting still functional but out-of-fuel sattelites instead of deorbiting them.

Maybe even to the point where future sattelites will not carry any more fuel than they need to reach GEO but will instead rely on occasional passes made by a dedicate "booster craft" that can be refueled in LEO.
baudrunner
2.3 / 5 (4) Apr 11, 2012
Why are we so obsessed with destroying things? I would gather those rogue and obsolete satellites using that device and just push them into a safe zone. There's always a future in salvage. Some day we might appreciate some of the clever technology that went into those satellite's instruments and save a lot of money recycling them. Considering what's happening in the private space sciences sector today, I foresee space hackers in our future.

Let's do that instead. It sounds like so much more fun.
jselin
5 / 5 (2) Apr 11, 2012
Burn it all up... risk management is more important. Putting it all in a "hoarding" orbit would be unstable not to mention the cost and complexity of retrieval and reuse. In the meantime collisions would disperse the material and create an unmanageable mess.
baudrunner
1 / 5 (2) Apr 11, 2012
jselin: nope.., there is no risk in managing the placement of all those derelict particles.. they can each be re-aligned a thousand times a second with one of those beam generators. It's the best way to go, trust me.
(the terms "object" and "particle" can be interchanged in physics)
Nephrops110
4.8 / 5 (5) Apr 11, 2012
"A geosynchronous orbit, one in which a satellite returns to the same position above the Earth each day"
and
"communications satellites have been placed in orbits from hundreds of miles to several thousand miles above sea level to create a fixed point in the sky"
Who wrote this? An object a few hundred miles up cannot possibly be a fixed point in the sky. The only place that happens is in geostationary orbit, which the article also describes incorrectly.

Plus, not one single sensible technical description of the system that is being proposed. Very poor article indeed
Torbjorn_Larsson_OM
5 / 5 (1) Apr 12, 2012
@ baudrunner:

It is commonly agreed that the junk is a risk, and indeed it has been known to make accidents. (Two crafts collided last year.) The risk involved in "hoarding" orbits is difficult to assess - what you describe is impractical (how to keep tabs on all these, use a beam nonstop with energy and refueling issues, et cetera), fraught with problems (objects passing near adn in front of each other), and expensive (who will pay for risk management) - and the dump alternative is what is used today.

"the terms "object" and "particle" can be interchanged in physics".

Nope, particles are objects but not all objects are particles in the classical sense of point-like, instead they are built of particles (in quantum field theory).
jselin
not rated yet Apr 12, 2012
jselin: nope.., there is no risk in managing the placement of all those derelict particles.. they can each be re-aligned a thousand times a second with one of those beam generators. It's the best way to go, trust me.
(the terms "object" and "particle" can be interchanged in physics)
I'm going to guess that you aren't a complex systems engineer or have demonstrated successes in complex project planning. Is that an accurate assessment? Not to make it personal but if I'm to trust you that this is the best way to go all I have left is to verify my source ;)
Egleton
not rated yet Apr 15, 2012
Park all the "Junk" at L4 or 5. We will be needing it later.
rwinners
not rated yet Apr 16, 2012
I like the hoarding idea, but think it might be limited to larger items. Someday, that mass might become useful. With gains in technology, that mass might actually be tethered and grow.
I wonder if ion engines can now produce the power to keep something like the space station in orbit?
Neurons_At_Work
not rated yet Apr 16, 2012
I wonder if ion engines can now produce the power to keep something like the space station in orbit?

From what I've read, Ad Astra has inked a deal with NASA to add two VASIMR 100KW plasma thrusters to ISS about 2014 for reboost and testing. Since there is not 200KW of free power available, batteries (50KWH) will be included to allow operation in 15 minute bursts. Each thruster will have opposite magnetic moments to avoid torque. The Taurus II is the scheduled launch vehicle. This is from RLV and Space Transport News, Aviation Week, and the Ad Astra site.
antialias_physorg
not rated yet Apr 16, 2012
Park all the "Junk" at L4 or 5. We will be needing it later.

Please look at the distances involved before making such comments.