Comet Hunter

  • Released Tuesday, September 29, 2015
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A sun-observing spacecraft discovers its 3,000th comet.

A sun-observing spacecraft discovers its 3,000th comet.

On September 13, 2015, the Solar and Heliospheric Observatory—a joint project of the European Space Agency and NASA—discovered its 3,000th comet, cementing its standing as the greatest comet finder of all time. Prior to the 1995 launch of the observatory, commonly known as SOHO, only a dozen or so comets had ever even been discovered from space, while some 900 had been discovered from the ground. Comets are essentially a clump of frozen gases mixed with dust. They circle the sun on various trajectories and are often pristine relics that can hold clues about the very formation of our solar system. SOHO's comet prowess, however, was unplanned, as its mission is to observe the sun and interplanetary space. Scientists say in its two decades in orbit it has opened up a new era of solar observations, dramatically extending our understanding of the star we live with. Watch the video to learn more.

Find out more about the SOHO mission and how the spacecraft finds comets in this video.

SOHO observes the space surrounding the sun by blocking out the bright light from its disk (white circle) and inner atmosphere (red circle).

SOHO observes the space surrounding the sun by blocking out the bright light from its disk (white circle) and inner atmosphere (red circle).

Comets streaming toward the sun, like the one in the lower-right corner, often show up in images taken by the spacecraft.

Comets streaming toward the sun, like the one in the lower-right corner, often show up in images taken by the spacecraft.

Launched in 1995, SOHO has monitored the sun for nearly 20 years from a distance of about 930,000 miles from Earth.

Launched in 1995, SOHO has monitored the sun for nearly 20 years from a distance of about 930,000 miles from Earth.

For More Information

See NASA.gov

Credits

Please give credit for this item to:
NASA's Goddard Space Flight Center

This page was originally published on Tuesday, September 29, 2015.
This page was last updated on Wednesday, May 3, 2023 at 1:49 PM EDT.