NASA scientists were well aware of the harm that could be caused to the instruments aboard the Mars Atmosphere and Volatile Evolution (MAVEN) spacecraft and other satellites orbiting the planet when the comet “Sliding Spring” had a close encounter with the Red Planet back in October of 2014, so they turned off much of the sophisticated equipment they were carrying.

But, according to an article on business-standard.com, some of the instruments were left running to measure what happened to the planet’s atmosphere as the comet passed within 140,000 kilometers of the surface, including the magnetometer aboard the MAVEN.

The scientists have now evaluated the data the device recorded and the results show the comet, with its own powerful magnetic field, wreaked havoc on Mars’ magnetic environment surrounding the planet.

Jared Espley, a MAVEN science team member at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, said the comet “plunged the magnetic field around Mars into chaos.”  Espley added the team thinks “the encounter blew away part of Mars’ upper atmosphere, much like a strong solar storm would.”

Fortunately, the Earth is protected by a strong magnetic shield generated within the planet, something that Mars does not have.  The envelope of gas generated from the comet’s core as it is heated by the Sun, known as the coma, flooded over the planet for several hours, with the inner coma nearly reaching the surface of Mars.

The resulting tide of magnetically charged particles from the comet quickly overwhelmed Mars’ weaker magnetic field, providing the chaos.  The disruption of the planet’s magnetic field lasted for a number of hours after the comet had passed by.  The researchers compared the event to a very strong, but short-lived, solar storm.

Espley wrote in a paper published in the journal Geophysical Research Letters, “The main action took place during the comet’s closest approach but the planet’s magnetosphere began to feel some effects as soon as it entered the outer edge of the comet’s coma.”

The paper’s authors remarked they were getting a better understanding of the interaction of the magnetospheres of both the comet and Mars and the processes that control them.