Comet Siding Spring (C/2013 A1)

Discovered in January of last year, it was quickly established that Comet Siding Spring (C/2013 A1) was going to pass incredibly close to our nearest neighbouring planet Mars.

Comet Siding Spring and Mars by Damian Peach

At 18:27 UTC on October 19th, Comet Siding Spring did indeed zoom by Mars, and at that time Comet Siding Spring was just 84,500 miles (141,000km) above the red planets dusty surface. That makes it the closest pass a comet has ever made to any planet in known history.

The image to the right was taken by astrophotographer Damian Peach several hours before Siding Spring made its closest approach to Mars. Click here for a larger version.

See below for ongoing real-time data…

Comet Siding Spring’s Path

Comet Siding Spring Animation

Mars Flyby

Comet Siding SpringComet Siding Spring passed Mars at a distance of just 84,500 miles (141,000km) above the red planet’s surface. In astronomical terms, this was incredibly close, just one third of the distance of that from the Earth to the Moon which is over ten times closer than any known comet has ever passed by our home planet.

Comet Siding Spring was at its closest point to Mars at 18:27 UTC on October 19th, 2014, its perihelion (its closest point to the Sun) occured on October 25th. The comet reached a peak magnitude of +9.6 on September 9th.

Dust Jets

After various processing techniques, the image below (taken by NASA’s Hubble Space Telescope on March 11th) shows what appears to be two separate jets of dust being spewed in opposite directions from Comet Siding Spring’s nucleus.

Comet Siding Spring.  Credit: NASA

NASA took evasive action with the various spacecraft they currently have orbiting Mars to minimise the possibility of sensitive instruments being damaged on the spacecraft from the high intensity of dust particle strikes expected as the comet passed by.

Related article: NASA Preparing to “Duck and Cover” for Mars’ Close Encounter with Comet

Comet Siding Spring image: © Damian Peach (used with permission). Hubble image and animation courtesy of NASA/JPL-Caltech.