We have four objectives, Ken Williford, Deputy Project Scientist for NASAs Mars 2020 mission, told Astronomy earlier this year. The first three are really our core science objectives. And the fourth is preparing for human exploration.

Perseverances science objects are: seeking out sites that were potentially habitable in the past, looking for signs of ancient microbes within rocks known to preserve life, and collecting and storing promising rock samples for a future return mission.

The rover aims to accomplish these goals using a unique and sophisticated suite of instruments including a rock-blasting laser, microphones and cameras, a powerful coring drill, a mobile weather station, and the first ground-penetrating radar ever sent to Mars surface. Although there are some new additions to Perseverance, many of these high-tech tools are just upgraded versions of what the Curiosity rover carried to the Red Planet in 2012. And thats because NASA is employing what they call the heritage approach for Perseverance, borrowing what worked from Curiosity.

[Perseverance] is something like 90 percent spare parts from Curiosity, Jim Bell, principal investigator for Perseverances Mastcam-Z instrument, told Astronomy earlier this year. Thats how they got the mission approved, because they could save an enormous amount of money by using those spare parts.

But that doesnt mean Perseverance is cheap. Its still about a $2-billion project, and NASA expects to spend up to a total about $2.7 billion over the entirety of the mission.

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Mars 2020 launch: NASA's Perseverance rover ready for the Red Planet - Astronomy Magazine