EXPLORE


JOINRENEWJOIN

Messages from Earth
  

Space Topics

Stardust


On January 15, 2006 Stardust brought back to Earth something that scientists have never seen and never examined: dust samples taken directly from the coma surrounding a comet's nucleus.

Stardust flew within 236 kilometers (147 miles) of the nucleus of comet Wild 2 on January 2, 2004. It passed through Wild 2's coma – the cloud of gas and dust surrounding the comet – crossing on its way a series of powerful jets streaming out from the comet. It braved the most intense bombardment ever endured by a man-made spacecraft in order to scoop up particles that may tell us about the materials that helped shape our solar system.

Stardust collected the coma particles by extending a paddle-shaped particle collector, composed of an ultralight compound known as aerogel. As the spacecraft passed through the dust cloud at a relative speed six times greater than a rifle's bullet, particles from the coma became embedded within the aerogel. Shortly after, the aerogel plate was removed from the collector arm and stored inside the sample return capsule. When the capsule returned to Earth, it carried with it these pristine samples, collected only hours after they left the comet's surface.

During its harrowing flyby of Wild-2, cameras on board Stardust took 72 pictures of the comet's nucleus and jets. Instead of the expected fluffy, uniform ball, Wild 2 turned out to be pockmarked with craters and peaks -- not at all what scientists expected. It looks, in fact, like no other known object in the solar system

In addition to cometary dust, Stardust's sample return capsule contains another type of particle never seen on Earth: interstellar dust originating outside the solar system. Stardust picked up these samples over 195 days of its long cruise to Wild 2. To collect them, the spacecraft used the same aerogel collector used in the Wild 2 encounter, however it used the reverse side of the plate. When the collector is returned to Earth, one side of it will contain cometary dust, the other interstellar dust. While there will be thousands of comet particles, there will only be dozens of interstellar dust particles, and the Stardust team has invited public participation in a project called "Stardust@home" to search for those cosmic needles in a haystack.

The Stardust spacecraft is now in solar orbit, and an extended mission has been approved: it will fly by comet Tempel 1 on February 14, 2011. Stardust will be the second visitor to Tempel 1; the first, Deep Impact, smashed an impactor into the comet's nucleus, creating a crater that was obscured from view to Deep Impact's cameras by dusty ejecta. Stardust's return to Tempel 1 will provide the first cloudless views of the impact site.

Stardust Facts
Launch Date: February 7, 1999
Comet Wild 2 Flyby: January 2, 2004
Sample Return Capsule Landing: January 15, 2006
Comet Tempel 1 Flyby: planned for February 14, 2011