Scientists have recently shaken up our perception of Mars. A NASA team has directly shown that Mars is seismically active – much more than scientists expected, too. The findings were published earlier this year in Nature Geosciences. This discovery was reported as part of a larger batch of findings reported from the first 10 months of NASA’s InSight campaign to observe Mars’s environment.
The large spacecraft called InSight landed in a massive crater on Mars back in November 2018. Packed with sensors to observe various aspects of the planet’s environment, the lander has been relaying information to the NASA team ever since. One of the sensors was a seismometer, marking the first time that humans managed to directly measure marsquakes (these are like earthquakes, but on Mars). The seismometer behaves somewhat like a stethoscope pressed against the planets surface. Through this, the NASA researchers observed 174 marsquakes since they started observing the planet. The quakes are much more gentle than those on Earth, but it’s a surprise that they’re occurring much at all.
Earthquakes are largely caused by moving tectonic plates. Scientists believed that tectonics on Mars stopped moving long ago. But the characteristics of the marsquakes that InSight observed suggest they also originate from tectonic motion. On Earth, tectonic plates move because the planet’s core is so much hotter than its surface, creating motion through the heat difference between the layers. If Mars has unexpectedly high tectonic activity, then one possibility is that its core is hotter than scientists thought. The discovery of unexpectedly high seismic activity may require us to change our understanding of what Mars is made of and how it’s been changing over time.
While the findings released from InSight are already exciting, the campaign is planned for 2 years total. There are many more observations in store. Accordingly, the NASA team has emphasized that they’ll be gathering the rest of the data before drawing overarching conclusions about the red planet and how we might need to refine our understanding of it.
Managing Correspondent: Jordan Wilkerson
Scientific Article: The seismicity of Mars. Nature Geoscience
Image Credit: NASA (IPGP/Nicolas Sarter)