Using radar from an orbiting spacecraft to penetrate the hidden recesses of Mars, planetary prospectors have uncovered vast reserves of water-ice buried beneath rocky debris.

During an experiment in Fermilab's Tevatron particle accelerator, a group of elementary particles called muons showed up in a strange place. Physicists are considering the likely implications.

The first images of a planetary system beyond the solar system are released, while the Hubble Space Telescope snaps a shot of likely planet orbiting a nearby star.

Even as the Hubble Space Telescope was able to snap an image after several weeks of idling, a mission to visit and upgrade Hubble suffered another delay.

Epsilon Eridani hosts an inner asteroid belt and planet arranged like those in the solar system. (p. 13)

A plan to switch the Hubble Space Telescope to a backup system works, waking up the telescope after more than two weeks of silence. (p. 8)

Planetary scientists have gotten their closest look yet at polar storms on the ringed planet. These polar cyclones are big enough to engulf Earth. (p. 9)