NASA’s Mars InSight lander has detected its three most powerful quakes yet.
On 25 August, InSight detected two quakes, at magnitude 4.1 & 4.2. Then, on 18 September – the lander’s 1,000th Mars day of operation – it picked up the rumbles of another magnitude 4.2 quake.
These new quakes blow the previous record of a magnitude 3.7 quake detected in 2019 out of water. Fascinatingly, the largest of August quakes was most distant detected yet, with an epicenter some 8,500 kilometers (5,280 miles) from InSight.
Analysis remains ongoing, but scientists are excited about the likelihood of learning something new about the inside of the Mars .
“Even after quite two years, Mars seems to possess given us something new with these two quakes, which have unique characteristics,” said planetary geophysicist Bruce Banerdt of NASA’s reaction propulsion Laboratory.
InSight, squatting stationary on surface of Mars, instrumentation primed to detect rumbles & grumbles of the planet’s belly, has been operational since 2018. During that point , lander has given us a wealth of latest new information.
First, there was direct detection of mars quakes in first place. That’s an enormous big deal, because Mars had been considered geologically dead. Now we all know surely that there is enough happening within the interior to stay things occasionally trembling.
Second, mars quake data is allowing planetary scientists to map Martian interior. When acoustic waves bounce around inside Mars & propagate through materials of various densities, the resulting signals are often decoded to work-out what & where – those materials are. It’s how we map Earth’s interior, too. In this way, scientists earlier this year determined that Mars features a larger-than-expected, low-density liquid core.
The newly detected quakes bring something new to table.
Firstly, most of massive quakes detected by InSight so far are from much closer to its landing site, in region called the Cerberus Fossae, around 1,600 kilometers from InSight. Here, a series of fissures are often found, created by faults that pulled the crust apart. Evidence suggests that region was tectonically & volcanically active recently, i.e., within last 10 million years.
Scientists are yet to research September quake, or precisely pinpoint the epicenter of larger of the 2 August quakes, but they’re watching another region that shows signs of past volcanic activity – Valles Marineris, a huge canyon system that gouges a 4,000 kilometer path across the face of Mars. Centre of this system is 9,700 kilometers from InSight.
The 2 August quakes also delivered different seismic profiles. The 4.2 magnitude quake was slow & low-frequency, and the 4.1 magnitude quake was faster & better . it had been also much closer, a mere 925 kilometers from lander.
Different seismic profiles can mean different processes at play within Mars, but they also help with aforementioned Mars interior mapping, since they will help put together a more detailed reconstruction of interior densities.
InSight, the poor little ducky, hasn’t exactly been having a simple time of it. First, it had some issues with its burrowing instrument, the Mole, designed to watch heat flow. The Mole was pronounced dead earlier this year. And, although lander received a 2 year mission extension, it suffered some power issues when its solar panels became coated in dust.
In May of this year, scientists cleverly fixed this by directing InSight to trickle sand next to solar panels on a windy day. The larger grains hit panels & bounced off, collecting smaller dust within the process, leading to a big power boost. The action was performed several times, restoring lander’s functionality.
“If we hadn’t acted quickly earlier this year, we’d have missed-out on some great science,” Banerdt said.