NASA’s Stardust-NExT (New Exploration of Tempel) spacecraft has a date on Valentine’s Day with Comet Tempel 1. While it won’t be carrying a box of chocolates, the craft will pay homage to the comet by snapping 72 high resolution photos as it flies by at 22,400 mph only 124 miles above its surface.
Stardust is the second spacecraft to visit Comet Tempel 1. The first was NASA’s Deep Impact probe in 2005, which dropped an 820-lb. metal projectile onto the comet’s surface and photographed the resulting flash of impact. Deep Impact was later re-purposed and sent on to Comet Hartley 2 ,where it took spectacular photos last year of fluffy snowballs shooting out of fissures in the comet’s crust.
Stardust was originally sent out to photograph the surface and collect dust samples from the atmosphere of Comet Wild 2 in 2004. The precious particles were later returned to Earth in a science canister that landed in the Utah desert. Realizing there was still life in the old probe, NASA mission planners redirected it to Comet Tempel 1, the first comet to be visited by two spacecraft.
Comets are volatile creatures. They spew dust, water vapor and other materials into space as they’re heated by the sun. Some of that material is literally blown back by the sunlight to form a tail; the remainder forms a misty, temporary atmosphere around the comet’s icy nucleus.
Scientists hope to see changes in the surface layers of Tempel 1Â since it was last photographed up close six years ago. They’d also like to get a look at the crater produced by the impact of that projectile. Dust and debris from the blast obscured it from view at the time.
Who knows what we’ll discover. Take a look at those “pancake layers” in the closeup photo (left) of Tempel 1 – mighty peculiar for a small body like a comet. On Earth we have layers of sedimentary rock created through the action of flowing water and winds. Is icy material somehow flowing on the comet or is their another cause?
“One idea is that two protocometary bodies collided at low speeds and smushed together to form something like a stack of flapjacks,” says Pete Shultz, Stardust-NExT co-investigator.
Comet pancakes … hmmm. That gives me an idea for Valentine’s Day. Stay with us in the coming week for the latest on the Stardust NExT mission.