Astronomy Picture of the Day

Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.

October 26, 1998
See Explanation.  Clicking on the picture will download 
 the highest resolution version available.

An Ion Drive for Deep Space 1
Credit: New Millennium Program, JPL, NASA

Explanation: Space travel entered the age of the ion drive Saturday with the launch of Deep Space 1, a NASA mission designed primarily to test new technologies. Deep Space 1 is bound for asteroid 1992 KD in July 1999. Although the ion drive on Deep Space 1 provides acceleration much smaller than we feel toward Earth, it will gradually give the spacecraft the speed it needs to travel across our Solar System. The propulsion drive works by ionizing Xenon atoms with power provided by large panels that collect sunlight. As these ions are expelled by a strong electric field out the back, the spacecraft slowly gains speed. Pictured above, hot blue ions emerge from a prototype drive that was successfully tested last year at JPL.

Tomorrow's picture: Henrietta Leavitt Calibrates the Stars

< Archive | Index | Search | Calendar | Glossary | Education | About APOD >

Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (USRA)
NASA Technical Rep.: Jay Norris. Specific rights apply.
A service of: LHEA at NASA/ GSFC
&: Michigan Tech. U.