Monday, October 24, 2011

Buying parts from the orbital scrapyard?

That's what the latest project from the Defence Advanced Research Projects Agency (DARPA) sounds like. They call it the Phoenix Program.

Communication satellites in geosynchronous orbit (GEO), approximately 22,000 miles above the earth, provide vital communication capabilities to warfighters. Today, when a communication satellite fails, it usually means the expensive prospect of having to launch a brand new replacement communication satellite. Many of the satellites which are obsolete or have failed still have usable antennas, solar arrays and other components which are expected to last much longer than the life of the satellite, but currently there is no way to re-use them.

The goal of the Phoenix program is to develop and demonstrate technologies to cooperatively harvest and re-use valuable components from retired, nonworking satellites in GEO and demonstrate the ability to create new space systems at greatly reduced cost. Phoenix seeks to demonstrate around-the-clock, globally persistent communication capability for warfighters more economically, by robotically removing and re-using GEO-based space apertures and antennas from de-commissioned satellites in the graveyard or disposal orbit.

The Phoenix program envisions developing a new class of small ‘satlets’, or nano satellites, which could be sent to the GEO region more economically as a “ride along” on a commercial satellite launch, and then attached to the antenna of a non-functional cooperating satellite robotically, essentially creating a new space system, leveraging the System F6 architecture. A payload orbital delivery system, or PODS, will also be designed to safely house the satlets for transport aboard a commercial satellite launch. A separate on-orbit ‘tender,’ or satellite servicing satellite is also expected to be built and launched into GEO. Once the tender arrives on orbit, the PODS would then be released from its ride-along host and link up with the tender to become part of the satellite servicing station’s ‘tool belt.’ The tender plans to be equipped with grasping mechanical arms for removing the satlets and components from the PODS using unique space tools to be developed in the program.

. . .

The first keystone mission of the Phoenix program in 2015 plans to demonstrate harvesting an existing, cooperative, retired satellite aperture, by physically separating it from the host non-working satellite using on-orbit grappling tools controlled remotely from earth. The aperture will then be reconfigured into a ‘new’ free-flying space system and operated independently to demonstrate the concept of space “re-use”.

There's more at the link. Here's a video discussing the program.

When you think about it, this program makes a heck of a lot of sense. If you can build a satellite without having to include bulky, complex aerials (which have to be stored in a folded position, and unfolded for use once the satellite is in orbit), you can make it much smaller and lighter. Since those components are already in orbit, no longer needed by their 'parent' satellite, it should be relatively simple to craft a connecting cable to plug the new satellites in to the old aerials.

Given that the lowest currently available cost (using the Russian Proton rocket) to lift a satellite from the Earth's surface to geosynchronous orbit (not low earth orbit) is about $8,000 per pound of weight, and that US launch systems are several times more expensive, cutting the launch weight by several hundred pounds adds up to a pretty massive saving in cost. Just goes to show . . . there's at least one government program that I think is economically rational and reasonable!



Dirk said...

Not only does this make a great deal of sense, it's also way cool. As one of the bloggers I read would say, "we're living in the future." :)

Mark said...

Actually this could help offset the cost of the I.S.S. If they satellites in question could be captured and brought to the I.S.S to be refurbished, then sent back out the cost saving simply from not having to launch a new from earth to orbit could be immense.