This image shows Comet Linear brightening when it blew off part of its crust. Clicking on this image will show you the Hubble Space Telescope's chronicle of the outburst.
Click on image for full size
Courtesy of the Hubble Space Telescope, NASA, and H. Weaver at Johns Hopkins University

Comet Linear

A comet was discovered on September, 27 1999, by the Lincoln Near-Earth Asteroid Research program in New Mexico. It's no wonder this comet has an official name of C/1999 LINEAR S4. Most people simply know this comet as Comet Linear.

Comet Linear had its closest approach to the Sun on July 26, 2000. It was still 114 million kilometers (.76 AU) away though! It became a 6th magnitude object around that time, which means it was about as bright as the faintest stars you can see without any aide. The comet is still visible, but you'll need binoculars or a telescope to see much!

Scientists aren't sure if Comet Linear has ever been to our solar system before and they are not sure if it'll ever return. If the comet does return, it may be millions of years from now.

While here, astronomers thought LINEAR would not be as spectacular as other recent comets like Hyakutake and Hale-Bopp. After all, it was likely to be 20 to 100 times dimmer than Hyakutake. But, LINEAR did put on a tremendous show for the Hubble Space Telescope. The Hubble was tracking the comet for two days, July 5-July 7. At 6:32 p.m. EDT on July 5th, comet Linear blew off a piece of its crust. The Hubble telescope watched the light brighten by an extra 50% in less than four hours. The eruption threw off a great deal of dust into space. Astronomers can certainly learn about comet structure from this incident.

Comet Linear has an orbital inclination of 149 degrees and an eccentricity of 0.999.

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