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Comet Probes Given New Duties
iamlucky13 writes "In January of 2004, the NASA's Stardust mission made a flyby of comet Wild-2, taking images and collecting samples from its tail that have since been returned to earth in a detachable capsule. On July 4, 2005, Deep Impact smashed a 350 kg projectile traveling 37,000 km/h into comet Tempel 1 as part of its studies of that object. With both craft in good shape at the end of their missions, NASA has been considering additional tasks for the probes. These plans have now been confirmed with a variety of tasks costing an estimated 15% what a new mission would. Among the new duties will be a revisit of Tempel 1, a flyby of comet Boethin, and transit studies of known extra-solar planets."
Mass Margins are really tight when a mission is in the planning phase... there are times when a mission can have a follow on mission (e.g. Mars Global Surveyor had a relay antenna so that it could relay data while in orbit around Mars), but for the most part, every part of the mission is tailored specifically for the task at hand. Secondary missions are just that, an after-thought of what could be done with the hardware that is on board. Fortunately, the scientists are creative enough to explore this and come up with some really good ideas on how to use the on board equipment for solid science.
I guess thats all I have to say.
But then if it didn't manage all of it, people would point and say "Look, see? NASA sucks!" It's much better for them, in my opinion, to underestimate how much they'll be able to do with it. Then they're almost certain to get what they planned done, and this extra stuff is seen as a bonus.
All right, answered my own question, looks like you can detect third bodies and odd geometries (like rings) by looking for non-symmetric parts in the intensity variation as it transits the star. Found this paper ftp://ftp.iac.es/tepstuff/lisbon98/deeglis98.pdf (PDF file, I can't vouch for the site.) which describes some of the variations in the shape.
I guess the camera has a high dynamic range but not particularly strong light collecting capabilities, which makes it ideal for doing this with bright, nearby stars, especially with all the assets already on orbit, where all that needs to be done is point and click. Pretty cool trick.
This is a really great precedent for them to set for the future.
Precedent? Hardly. Voyager 2 was originally only planned to flyby only Jupiter and Saturn. The engineers worked without permission from NASA management to build the spacecraft to be able to do a successful flyby of Uranus and Neptune (the probes had an official specification of their lifetimes of something on the order of 3 years or so). Eventually they were able to convince the management that if Voyager 1 was operating safely in space and was looking like it was going to be able to get a good look at Titan then Voyager 2 could reprogram its trajectory so that it could do the flybys of Uranus and Neptune. It was not possible for the Voyager probes to do the specified flyby of Titan and also visit Uranus and Neptune. If Voyager 1 would have blown up or had a problem in space then Voyager 2 would have done the flyby of Titan.
Though to be honest, I'm not even sure if this mission set the original precedent of mission extensions to check out other stuff.
Suddenly, the hairy finger of a familiar monkey tapped me on the shoulder. It was time.--G. T.