Once it's been sent to Earth, they drop it. Curiosity's main computer had a flash drive of 2GB, and each of the big cameras had an 8GB flash drive on board. I d

Once it's been sent to Earth, they drop it. Curiosity's main computer had a flash drive of 2GB, and each of the big cameras had an 8GB flash drive on board. I doubt Perseverance is much changed from that; the main computer is IIRC a spare part from the Curiosity production. Rad-hardened computer hardware is expensive and bulky. You don't add storage or processing power that you don't absolutely need. See https://www.ontrack.com/en-us/blog/how-to-store-data-on-mars https://www.ontrack.com/en-us/blog/how-to-store-data-on-mars and https://mars.nasa.gov/mars2020/spacecraft/rover/brains/ https://mars.nasa.gov/mars2020/spacecraft/rover/brains/