Scientists have been studying the effect that the flyby of Comet C/2013 A1 had on planet Mars after the event took place in October 2014. Despite the fact that the comet came no closer than approximately 87,000 miles from the planet itself, it would appear that the impact was gigantic at a magnetic level; even if it only lasted for a few hours.
The way scientists are discovering these things just now is the result of months of research based on the data gathered by the NASA Mars Atmosphere and Volatile Evolution spacecraft (MAVEN) that entered the orbit of the red planet just several weeks before the comet’s flyby. The flyby had been expected for a while, and the craft was ready for defensive procedures.
As the comet was approaching, MAVEN switched all of the sensitive equipment off in order to prevent damage, a technique that all of the other Mars orbiters followed. But not all systems were turned off, with several tools such as a magnetometer remained online to be able to gather data from this extremely rare event. Thus, the MAVEN spacecraft was able to collect multiple series of ‘first-hand’ data regarding the magnetosphere of the planet and the effect that the comet had on it.
According to the study that has been undergoing at NASA since the flyby of Comet C/2013 A1, the effect was downright enormous. According to the scientists, it ‘set off the magnetosphere around Mars into chaos’, along with blowing away a small portion of the red planet’s upper part of the atmosphere.
While that sounds like a terrifying prospect for our planet, should a comet flyby take place near us next time, things are relatively different if you’re to compare Earth to Mars. Earth’s magnetic field is a lot stronger than Mars’; on top of that, the red planet’s magnetosphere is not uniform, having areas where it is patchy and doesn’t completely wrap around the object.
Comets, when interacting with solar winds, produce their own magnetic fields. As a result, when Comet C/2013 A1 flew so close to planet Mars, the former’s magnetism had an outstanding effect on the latter, creating a rather rattling effect that took several hours to calm down. Even as the comet was only drawing near, Mars’ magnetic field started reacting and realigning to various directions. According to scientists, when the comet flew by, Mars’ magnetic field began ‘flapping like a curtain beaten by the wind’, an effect that took hours to end.
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