This Sunday, a comet the size of a mountain will come within 87,000 miles of Mars at a speed of 126,000 mph. This event happens approximately once every million years.
The comet has been dubbed ‘Siding Spring’ after the Australian observatory that first identified it, but the scientific name is C/2013 A1. The gas cloud surrounding the comet is 12,000 miles across and the tail of the comet is the equivalent of the distance between the Earth and the moon.
After the comet was discovered in January 2013, scientists at both NASA and the European Space Agency (ESA) worried that dust from the comet could damage spacecrafts orbiting Mars. Both NASA and the ESA decided to change the routes of their orbiters in order to avoid any potential damage.
"There's a small probability of an impact, but it's not zero," Richard Zurek, chief scientist for the Mars Program Office at NASA's Jet Propulsion Laboratory, told the Los Angeles Times. "And it only takes one to do you in.”
The comet Sliding Spring is made up of icy debris that is believed to be remnants from the formation of the solar system 4.6 million years ago. Scientists are hopeful that the comet’s journey to the inner solar system will help them collect new data on how the planets were formed. John Grunsfeld, astronaut and associate administrator for NASA's Science Mission Directorate, told ABC News that this event is a "cosmic science gift that could potentially keep on giving.”
Amateur astronomers in the U.S. should reconsider breaking out their telescopes. "From the Earth it is what we call an 11th magnitude object, which means it would take a good telescope at least 6 inches wide and a very dark sky to find the comet, Carey Lisse, principal scientists at Johns Hopkins University Applied Physics Laboratory, told the Los Angeles Times.
Even with a powerful telescope, the comet will not be visible in the Northern Hemisphere unless you’re within 10 degrees of the equator. However, if you want to watch this unique cosmic event, you can watch a live stream on the astronomy website Slooh.com, which starts at 11:15 a.m. PDT on Sunday.
Image via NASA