Comet Siding Spring's Close Flyby Caused a Meteor Storm on Mars

When Comet Siding Spring brushed past Mars, scientists captured data using NASA's MAVEN mission. Now, researchers have found that the comet was actually the cause of an intense meteor shower and added a new layer of ions, or charged particles to the ionosphere.

The comet itself traveled from one of the most distant regions of our solar system, called the Oort Cloud. From there, it sped toward Mars and made its close approach within about 87,000 miles of the Red Planet, which is less than half the distance between the Earth and our moon.

"MAVEN was well suited for studying the effects of the dust from the comet in the Martian atmosphere, because it makes measurements at the altitudes where the dust was expected to have an effect," said Bruce Jakosky, the principal investigator of the MAVEN mission, in a news release. "We also should be able to see if there are long-term effects from the comet dust in that same region of the atmosphere."

The MAVEN used its remote-sensing Imaging Ultraviolet Spectrograph (IUVS) and took direct samples in order to learn more about the comet. In fact, the scientists were able to obtain direct measurements of the composition of dust from an Oort Cloud comet.

"They call this comet encounter a once-in-a-lifetime event, but it's more like a once-in-a-million years," said Nick Schneider, one of the researchers. "MAVEN got there just in time, and we were ready. The number suggest a Martian would have seen many thousands of shooting stars per hour-possibly enough to be called a meteor storm-so it must have been a spectacular event that night on mars."

The findings reveal a bit more about the comet and the Oort Cloud. Because the Oort cloud contains some of the oldest materials in our solar system, the findings could allow scientists to better understand the evolution of our planet and other bodies in the solar system. In addition, the new research reveals a bit more about the effects on Mars, which will be important to note going forward with future space missions.