The robotic Mars probe provided valuable data
Q: What was the InSight mission, when was it launched and what was it supposed to do?
A. InSight is a robot sent to explore Mars. Unlike a rover that spins around, the InSight is a lander that stays in one place. NASA, working with partners in Europe, developed InSight and launched it in May 2018. InSight reached Mars six months later, in November 2018, landing on Elysium Planitia, a wide plain near the Martian equator.
Unlike the rover, which focuses on exploring the geology near the surface, InSight had a different goal: to better understand the interior of Mars. This is because InSight was equipped with specialized tools that allow scientists to “look under the hood” of the planet.
For example, much of what we know about the structure of the Earth deep beneath our feet comes from seismographs, which are the instruments that measure earthquakes. That’s because the same seismic waves that cause shaking in an earthquake can travel deep into Earth’s interior and give clues to the structure of the planet itself. So InSight is designed to use the seismometer and other time-tested instruments, including probes to measure magnetic signals and heat flow from the interior, to study a different planet.
s. How many years was the data sent back?
a. Just over four years on Earth. InSight landed on Mars on November 26, 2018, and NASA announced that it lost the signal from the rover on December 21, 2022. The rover was gradually losing power as dust covered its solar panels.
Q: What did scientists learn about Mars from the mission?
A. Earthquakes occur regularly on Mars. InSight has detected more than 1,300 earthquakes, and dozens of them have been interpreted as being caused by the movement of molten rock underground.
InSight also detected tremors caused by a meteorite impact, the effects of which were then documented with satellite imagery. The collision excavated a small crater that revealed water ice near the surface, closer to the equator than had ever been detected. The ice was discovered using color images from the satellite. There are some slight differences in chemistry, but at first glance, it’s like water ice on Earth. But the biggest benefit to scientists wasn’t actually the earthquakes themselves, but what they reveal about the planet’s internal structure, including the thickness of the crust, mantle, and core.
InSight has been looking not only at the planet’s interior, but also at the atmosphere, recording the most detailed weather data ever collected from Earth for an entire Mars year. As a secondary part of the science mission, InSight acted as a local weather station and recorded wind direction, speed, air temperature, and pressure over the course of an entire year. NASA made a nice dashboard that displays information not unlike what you might see in a TV weather forecast. There has never been this much data from Earth on Mars, so it will benefit all kinds of atmospheric studies.
Q: Does this alter and/or confirm what scientists thought they knew about the planet?
A: We had limited prior information about the interior of Mars, especially the core. One line of reasoning holds that the core cooled and solidified in the distant past. Instead, data from InSight indicates that the core is mostly liquid and is also less dense and larger than expected — with a radius of 1,800 kilometers, which is just over halfway from the planet’s center. The similarities and differences between Mars, Earth and other rocky bodies in the inner solar system give clues to how planets formed and evolved.
We also tend to think of Mars as a geological sleeper, which it is, in some important ways. However, InSight provided a fresh reminder that there are still active and interesting geological processes going on on the planet.