Earth is being pelted by comet dust this week — the small grains of rock and dirt that make up the Quadrantid meteor shower. The bigger ones will vaporize as they zip into Earth’s atmosphere, forming the streaks of light known as meteors. We’ll have more about the meteor shower tomorrow.
A spacecraft flew through another trail of comet dust 10 years ago tomorrow. It captured a few of those grains and brought them to Earth. Scientists are still studying those grains today.
Stardust was launched in 1999. It flew past one comet three years later, then sailed into the storm of debris around Comet Wild 2 on January 2nd, 2004, passing less than 150 miles from the comet. It used a pillowy material known as aerogel to catch bits of dust flying off the surface.
Scientists are interested in comets because they’re leftovers from the birth of the solar system. Studying their composition reveals important details about the mixture of ingredients from which Earth and the other planets were formed.
Stardust dropped off a capsule holding the precious comet dust in 2006. Then it headed back away from Earth for a bonus mission — a rendezvous with a third comet, known as Tempel 1. Another craft had fired a high-tech cannonball at Tempel 1 a few years earlier, so Stardust showed how the comet had changed.
Stardust used up the last of its fuel in 2011, ending its mission of exploring the building blocks of the solar system.
Script by Damond Benningfield, Copyright 2013