SOHO observatory discovers 5,000th comet

The Solar and Heliospheric Observatory (SOHO) spacecraft, which follows Earth in its orbit around the Sun, has now discovered 5,000 confirmed comets.

The discovery comes after 28 years of observations, and SOHO was never intended to be a comet hunter.

The 5,000th comet was discovered on 25 March 2024 when a citizen scientist in the Czech Republic spotted it on SOHO imagery.

Comets are bodies of ice and rock that orbit the Sun, and periodically their orbits take them into the inner Solar System.

When this happens, heat from the Sun often causes the coma and tail to appear, making them prime objects to see in the night sky.

Some comets take hundreds of years to return; Some take almost no time at all.

SOHO's 5,000th comet takes only a few years to orbit the Sun and belongs to the 'Marston Group' of comets.

These comets are thought to be related to Comet 96P/Machholz, named after Brian Marston, the scientist who discovered the group using observations made by SOHO.

Comet 96P/Machholz passes the Sun every 5.3 years, making it a very short-lived comet.

5,000th SOHO comet discovery

5,000 of this^Th The SOHO comet was discovered by Hanji Tan, who participates in the NASA-funded Sungrazer project, which enables citizen scientists to report comets they find in SOHO images.

Dan, originally from Guangzhou, China, is pursuing a PhD in astronomy in Prague, Czech Republic.

„Since 2009, I've discovered 200 comets,” he says.

„I got into the Sungrazer project because I love looking for comets. It's exciting to see comets that have traveled through space for thousands of years shining so close to the Sun.”

NASA says most of the 5,000 comets discovered by Soho were discovered with the help of citizens working on the Sungrazer project.

„Prior to the launch of the Soho mission and the SunGrazor program, only a couple of dozen solar comets had been reported — that's all we knew,” says Carl Bottoms, a space scientist and principal investigator at the US Naval Research Laboratory. SunCrazer Project.

„We've finally reached this milestone — 5,000 comets — and I can't believe it.”

If you'd like to become a citizen comet hunter, learn more about how to get involved SunCrazer Project.