Seriously, that was a stunning event - the landing method must have had some herbs involved at the planning stage, but heck, it worked !
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Because the atmosphere is so thin, you can not get gentle descent rates with parachutes alone. well, reasonably sized ones anyway.
The early rovers dropped onto the surface inside a beach ball. When they did the Curiosity rover, they found that it was too heavy for the beach ball concept to work, and they had to figure out something different. But you don't want to burden the rover with having to carry around descent rockets for its whole mission life. So the Skycrane concept was born.
A brief story about parachutes. (kind of relevant for BRS systems)
At the conclusion of the earlier Mars Airplane design studies that I mentioned, all the design teams got together to try to coalesce all the knowledge and ideas that had emerged during the studies among the several groups. So there was a big meeting. This was around December 1999.
One of the members of the Langley team at that time was Juan Cruz, a lightweight-composites designer that had been part of the Daedalus project at MIT, along with Mark Drela, John Langford, Guppy Yungren, Bob Park, and a handful of other brilliant guys. So anyway, Juan Cruz brought up the issue of parachutes at the Mars Airplane design confab. We would need a parachute for the entry capsule, and we would need a parachute for the drogue to help with aircraft deployment. So Juan had this huge orange book that was like the bible for parachutes, and he plopped it onto the meeting table with a thud and said that someone needed to step up and become a parachute guru. There was a general quiet shuffling of feet and subtle backing away from the table, as if Juan had put a black mamba in the middle of the table. No one wanted to go anywhere near it. So Juan picked the book up and shrugged and said he guessed he would have a go at it.
Well, as it turned out, every single parachute that has been used for Mars missions since that time was designed by Juan, including the descent parachutes for Spirit, Opportunity, Curiosity, and now Perseverance. These were challenging development projects, with lots of trial and error and failure along the way. He did a parachute test in the NASA Ames 80 x 120 ft NFAC wind tunnel, where the canopy writhed like an octopus, where the flow on one side of the canopy would somehow trigger the collapse of the other side. He did a drop test from a helicopter where the whole canopy just shredded. But he got it all sorted out. No missions where ever delayed or failed because of problems with parachutes.