Yesterday, China released new images from its Mars rover. These were exciting enough on their own but things got even more exhilarating when one space journalist noticed a big hole under the rover, as first reported by Futurism.
"This is very cool. The hole blasted by China's Mars lander when it touched down on the Red Planet," tweeted Jonathan O' Callaghan along with a close-up of one of the new pictures.
Phil Metzger, a planetary scientist at the University of Central Florida, then tweeted further expert commentary about the hole and it turns out it might not be such a good thing.
"Now that's a crater," Metzger said. "Note the steep sides of the hole due to the cohesion of the soil. Now imagine a 40-ton lander and how big its hole will be. That hole will likely collapse (especially as the hole dries out over the coming weeks) sapping soil away from the footpads."
Now that's a crater. Note the steep sides of the hole due to the cohesion of the soil. Now imagine a 40 ton lander and how big its hole will be. That hole will likely collapse (especially as the hole dries out over the coming weeks) sapping soil away from the footpads. 1/2 https://t.co/IQAAkaGZRu— Dr. Phil Metzger (@DrPhiltill) June 11, 2021
The scientist went on to explain how soil sapping from the footpads may induce tilting of the lander and that that is just one of three risks of landing very large landers on Mars' soft soil. The second risk is ejecta hitting the lander as the rocket exhaust comes back up from the hole before engine cutoff and the third is ejecta hitting the surrounding hardware.
Metzger further noted that aerospace manufacturer startup Masten Space Systems, with support from the University of Central Florida, is working to solve the physics of rockets digging craters. The work will be crucial to understanding how to land safely on Mars and even on the moon.