Nucleus of Comet Wild 2

This picture shows two views of the nucleus of Comet Wild 2 captured by the Stardust spacecraft during its January 2004 flyby. The image on the left was taken when Stardust was about 500 km (311 miles) from the nucleus. Click on image for full size (39K JPEG) Image courtesy NASA/JPL.

The image on this page shows the best views we've ever had (so far) of the nucleus of a comet. On January 2, 2004, the Stardust spacecraft flew past Comet Wild 2 at a relative speed of roughly six kilometers per second (four miles per second). During that flyby the spacecraft shot 72 pictures of the comet; these are the best two. The nucleus of Wild 2 is about five kilometers (3.1 miles) wide. Stardust passed within 240 km (149 miles) of the nucleus at closest approach.

The spacecraft entered the comet's coma, the vast cloud of dust and gas surrounding the nucleus, on December 31, 2003. Besides snapping the best-ever pictures of a comet's nucleus, Stardust also collected particles of dust emitted by the comet. The mission will return those particles to Earth in a small capsule that is scheduled to land in the desert in Utah in January 2006. Scientists are eager to directly study material from a comet since they expect to learn a great deal about those "dirty snowballs" from even a few grains of dust.

This picture shows the nucleus of Comet Wild 2. The nucleus is shown from two different angles. Stardust took the pictures at different times as if flew by. Stardust was about 500 km (311 miles) from the nucleus when it took the picture on the left. Click on image for full size (39K JPEG) Image courtesy NASA/JPL.

The picture on this page shows the best views ever of the nucleus of a comet. It shows two pictures of the comet's nucleus that were taken at slightly different times. The pictures were taken by a spacecraft named Stardust.

Stardust flew by a comet named Wild 2 in January 2004. Stardust was a little bit further away from the comet when it took these pictures than the Space Shuttle is from Earth when it is in orbit.

The nucleus of a comet is a lump of ice and dust. The nucleus of Comet Wild 2 is about five kilometers (3.1 miles) wide. That may seem pretty big to you, but the nucleus is very small compared to the rest of the comet. When we see a bright comet from Earth, we are looking at the much larger coma and tails of the comet.

This picture shows the nucleus of Comet Wild 2. The nucleus is shown from two different angles. Stardust took the pictures at different times as if flew by. Stardust was about 500 km (311 miles) from the nucleus when it took the picture on the left. Click on image for full size (39K JPEG) Image courtesy NASA/JPL.

The pictures on this page show the nucleus of a comet. These are the best pictures ever made of the nucleus of a comet. The nucleus of a comet is a big lump of ice and dust. This one is about five kilometers (3.1 miles) wide.

When we see a bright comet from Earth, we don't see the nucleus. Something that is a few kilometers (miles) across probably seems pretty big to you. But in space something that size if really quite small. When we see a comet from Earth, we see the coma and tails of the comet. Those parts of a comet are much, much bigger than the nucleus.

These two pictures were taken by a spacecraft named Stardust. Stardust flew by a comet named Wild 2. It took these pictures as it flew by. Stardust took these pictures at different times, so it was looking at different sides of the comet each time. That is why the pictures look a little different.