Perseverance Lands on Mars
NASA released some stunning new imagery and video of Perseverance's recent landing on Mars. That video is embedded later in this post, but first I wanted to write briefly on where Perseverance landed, and why NASA picked the location that it did.
First, here is a map of where the various landers and rovers have landed on Mars over the years. This is what Perseverance's landing location looks like from Earth through an 8" Celestron SCT telescope. I took this imagery back on October 10, 2020, when Mars was at opposition from my backyard in Tulsa, Oklahoma.
Looking at a high-resolution map you can get a better idea of the landing location. Jezero crater, where Perseverance landed, is on the edge of a higher elevation region of Mars and a larger crater with much lower elevation. This crater is interesting because it appears that water flowed through the crater in the past.
High-resolution imagery from the Mars Reconnaissance Orbiter shows what appears to be a delta within the crater at the end of a river channel. A 3D model of the site shows this a little better and it is easier to visualize water flowing down the channel and through the delta region into what would have been a lake filling the crater.
This green line shows one potential path for the Perseverance rover to take up onto the delta, across a major channel in the delta, and up the former river channel and onto the crater rim. Perseverance will be taking samples of the regolith all along its path, to eventually be returned to Earth by a later mission. It will also do extensive testing of samples along its path and send that analysis data back to Earth.
The Perseverance landing (see video below), seems overly complicated because Mars is a challenging planet to land on. The atmosphere is dense enough to require a heat shield on atmospheric entry, but not dense enough to allow a rover of this size and weight to touch down gently using only a parachute. While the parachute used on this mission slowed the craft considerably, Perseverance would have crash-landed without another means of slowing down. So, a powered descent vehicle was used to provide a gentle landing.
It would be possible to use a powered descent vehicle all the way to the surface instead of using a parachute, but that would require a lot more fuel, and thus a larger descent vehicle, and thus a more powerful rocket to launch it from Earth. The powered descent vehicle then lowered Perseverance to the ground with cables before detaching the cables and flying off away from the rover. The powered descent vehicle lowered the rover from above instead of flying underneath it since if the craft landed with the rover on top of it, there would be some chance the rover could get stuck trying to get off the descent vehicle.
Anyway, here is the amazing video NASA released showing the landing from the point of view of the rover and the powered descent vehicle.
Finally, here is the first panoramic image created from Perseverance's cameras. I'll have a link below to where you can view the thousands of raw images that have already been transmitted from the rover's various cameras.
A video version of this post can be watched below.