Earth is not the only planet to feel tremors. In fact, Mercury also has something that scientists decided to call "Mercuryquakes" for obvious reasons, when they found in a study that Earth is not the only one with tectonically active plates.
Mercury, the innermost planet in the solar system, had been very mysterious until NASA's MESSENGER spacecraft orbited it in 2011. Prior to that, the only visits that it received were the flybys from the Mariner 10 probe that took the trip over 40 years ago.
It is about time that we learn more of the hot planet, though. According to Space.com, the Mariner 10 discovered that Merucry actually had a vast array of large fault scarps or cliffs, some of which are more than 600 miles long, and over 1.8 miles high.
These fault scarps usually form when rocks are pushed together and thrust upward along the faults and fractures of the planet's crust, much like the way some hills and mountains are formed on Earth. For Mercury, these scarps are said to have formed as wrinkles on the planet's surface, cooling over time, and even leading to the planet shrinking in size, with previous research suggesting that Mercury may have already contracted by about 1.8 to 8.7 miles in diameter. The study, which was published in Nature Geoscience, showed these scarps that indicated the shrinking size of the planet as it cools down from its molten years.
This discovery is especially exciting for researchers as it shows that Mercury's shrinking wasn't something that just happened in the distant past, but that it might as well still be going on, giving the planet a slot into the small circle of tectonically active planets, like Earth.
Jim Green, NASA's director for Planetary Science said. "This is why we explore. For years, scientists believed that Mercury's tectonic activity was in the distant past. It's exciting to consider that this small planet - not much larger than Earth's moon - is active even today."