Mars 2020 mission

The launch took place successfully on July 30, 2020 at 7:50 am EDT, aboard an Atlas V 541 rocket.

The Perseverance rover landed in Jezero Crater at 21:55 CET on February 18, 2021.

Mars 2020 is a space mission for the exploration of Mars that was developed by NASA, whose launch was successful on July 30, 2020 and its arrival on the surface of Mars was equally successful on February 18, 2021 at 21:55 CET. The mission is mainly focused on sending Perseverance to the surface of Mars, a rover derived from the predecessor Curiosity to reduce costs, to which several improvements have been applied. In addition to the rover, there is a small demonstration helicopter called Ingenuity.

The primary objectives of the mission consist in studying the habitability of Mars, investigating its past and looking for traces of possible biological life. Furthermore, the storage of geological samples is foreseen to allow the future Mars Sample Return mission to bring them to Earth in order to analyze them accurately.

The rover is based on the footprint and structure of Curiosity, and is in fact equipped with a radioisotope thermoelectric generator (MMRTG), or a generator of heat and electricity, based on the decay of plutonium, to power and heat the rover, as the average temperature on the surface of Mars is −63 ° C.

Compared to Curiosity, however, the rover has been equipped with an improved landing system. In particular, it has been able to count on two evolutions, the "Range Trigger" and the "Terrain-Relative Navigation".

The Range Trigger is the system that controls the timing of the opening of the parachute during the descent. Knowing one's position with respect to the planned landing site and delaying or anticipating the opening of the parachutes, it was possible to reduce the landing ellipse, i.e. the estimated arrival area, by 50%, thus reducing the risks of being in inaccessible areas or of little interest. Before then, the parachutes of the various probes that arrived on Mars have always been opened as soon as the capsule reached a suitable speed to do so; with this system, on the other hand, the parachute was opened at the most useful moment to get as close as possible to the landing site, obviously always remaining within the required speed parameters. For example, if the control system had noticed that the site had been passed, this would have commanded an opening earlier than the scheduled time; in the opposite case the opening would have been postponed by increasing the distance traveled in the fall.

Terrain-Relative Navigation, on the other hand, is an unprecedented system for determining the characteristics of the soil in the very last stages of landing. The computer that governed this phase of the mission had a high-resolution map of the landing site pre-loaded, made in previous years by the probes currently in Martian orbit and containing in turn all the areas that are dangerous or not recommended for landing. During the descent, the rover collected images in rapid succession of the area it flew over and, comparing them with the known map, calculated its position and the estimated arrival area. Had the calculated position been considered dangerous, the navigation system could have moved the landing to a preferable area within a radius of 300 m. Previously, 99% of areas considered interesting due to the possible presence of traces of biological compounds or particular geological structures were discarded as they presented possible dangers (rocks, slopes, etc.). With this navigation system it was instead possible to choose landing areas that had been closed until now, allowing the selection of areas with dangers that could then have been avoided by Terrain-Relative Navigation. 

Also in the descent phase, the MEDLI2 suite of instruments was also active, or the second generation of the MEDLI suite, (MSL Entry, Descent and Landing Instrumentation) which collected data such as atmospheric pressure and temperature and the heat shield, allowing to better characterize the Martian atmosphere for future missions. During the landing, several cameras were active, making it possible to film all phases of the landing: one camera filmed the parachute, one the ground at the bottom of the descent stage, one was pointed upwards towards the descent stage and a ' the other towards the ground. There is also a microphone that picked up the sounds during all stages.