The National Aeronautics and Space Administration (NASA) said on Oct. 9 that a mountain-size comet will fly by Mars this month and that it plans to observe the event using its fleet of spacecraft and robotic rovers.
The U.S. space agency said that comet Siding Spring will be within 87,000 miles from Mars, or less than half the distance between the Earth and the moon, on Oct. 19. As its get closest to the Red Planet by 2:27 p.m. EDT, the comet will hurl at a speed of about 126,000 miles per hour.
Also known as comet C/2013 A1, Siding Spring was first spotted in January 2013 in Australia's Siding Spring Observatory by astronomer Rob McNaught. It is estimated that the comet's nucleus is miles wide and the gaseous clouds that envelops its head is about 12,000 miles across.
The comet came from Oort Cloud, which is about 50,000 astronomical units from the sun and is made up of icy objects believed to be remnants from the birth of the solar system. NASA said that the proximity between the comet and Mars is 10 times closer than any comet that has passed by the Earth, and this will provide a rare opportunity for scientists to collect data about the Siding Spring and its effect on Mars' atmosphere.
"This is a cosmic science gift that could potentially keep on giving, and the agency's diverse science missions will be in full receive mode," said NASA's Science Mission Directorate associate administrator John Grunsfeld. "This particular comet has never before entered the inner solar system, so it will provide a fresh source of clues to our solar system's earliest days."
The space agency said that it will deploy its science assets including the spacecraft and instruments that are orbiting and roving in the Red Planet to capture images and study the extremely rare event. Earth-based observations will also be made but scientists said that instruments near the comet during the approach would be better at capturing data that could not be collected remotely from the Earth.
NASA was initially concerned that the dusty tail of the comet could pose risks to orbiting spacecrafts when the comet passes by Mars, but these concerns were somehow relieved with later assessments. The U.S. space agency, however, is not taking chances. It has decided to make changes to the satellites' orbits so they will be at the safer side of the planet during the riskiest part of the comet's approach.