Many of the objects you can see in the night sky are stars, large objects in space that produce light. Our galaxy, the Milky Way, contains more than 100 billion stars. Stars are so far away that their light does not reach us for years....

Bite-size introduction to two scientists-Hubble and Lemaitre-who played key roles in formulating the theory of the origin of the universe known as the big bang. Includes an interactive timeline on which you can plot out the approximate...

Students act as astronomers, studying stars in a patch of sky in our own galaxy. Using simulated data from spectroscopy and other real-world instrumentation, students learn to determine star positions, radial velocity, proper motion, and...

This site from IPAC is a series of images of various celestial objects and regions as viewed in infrared light. Each photo is accompanied by a caption.

On this site, you can learn about mysterious powerful forces that absorb light called black holes. Study the science of black holes in outer space.