All around the world, millions of people hushed on Feb. 18 to hear NASA aerospace engineer Swati Mohan â04 calmly call the play-by-play of the Mars 2020 Perseverance rover landing. Mohan, who graduated with a degree in mechanical and aerospace engineering, described the capsule containing Perseverance as it entered the thin Mars atmosphere at 12,000 mph, briefly becoming a fast-flying fireball and then deploying a supersonic parachute. The craft slowed and tossed its back shield away, while looking for a parking spot on the red planet. With the help of retrorockets and a sky crane, Perseverance slowed to a gentle 1.7 mph at Jezero Crater and came to rest.