On Oct. 18, 2014, a comet called Siding Spring will fly close by Mars, allowing NASA's instruments in the area, along with others, to get a front row seat view to this rare event.
Siding Spring, also known as Comet C/2013 A1, will get about 87,000 miles within the range of the red planet. This is closer than any comet has ever been seen flying by Earth and is less than half the distance from the Earth to its moon. This will, obviously, give astronomers a rare opportunity to gather data in an unprecedented way.
This comet is of specific interest to scientists because it comes from the Oort cloud, a region of space that lies on the outer edges of our solar system. It is there where scientists believe debris from the Big Bang reside, so studying an object that originated there means we might learn more about how our solar system formed, as well as where life began. Siding Spring is the first comet from the Oort cloud we've ever studied up close.
"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," says John Grunsfeld, associate administrator for NASA's Science Mission Directorate. "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."
In preparation of Siding Spring's arrival, NASA is pointing all of its nearby instruments at the comet for gathering data. NASA will maneuver its three orbiters— the Mars Odyssey orbiter, Mars Reconnaissance Orberter (MRO) and the Mars Atmosphere and Volatile EvolutionN (MAVEN) out of the comet's debris path and into positions where they can study the comet. These orbiters will measure the comet's size and activity, as well as get an analysis of the composition of the comet's coma and dust particles of its tail.
From Mars' surface, both of NASA's rovers, Opportunity and Curiosity, will look up and observe the comet.
From Earth, the Infrared Telescope Facility in Hawaii will observe the comet. In space, Hubble, Kepler, Swift, Spitzer and Chandra will also track it. Other instruments already watching the comet include the Near-Earth Object Wide-field Infrared Survey Explorer (NEOWISE), Solar TErrestrial RElations Observatory (STEREO), Solar and Heliophysics Observatory (SOHO) and the Balloon Observation Platform for Planetary Science (BOPPS).
