As NASA's Perseverance rover is not flying to Mars with a mechanic, the US space agency has readied an Earthly twin of the six-wheeler in a bid to avoid as many unexpected issues as possible after the rover lands on February 18, 2021.Engineers expect to take it out of its garage home at NASA's Jet Propulsion Laboratory in Southern California next week into the Mars Yard, where a field of red dirt studded with rocks and other obstacles simulates the Red Planet's surface, the US space agency said on Friday.This rover model passed its first driving test in a relatively tame warehouselike assembly room at JPL earlier this week, NASA said."Perseverance's mobility team can't wait to finally drive our test rover outside," said Anais Zarifian, the mobility test bed engineer at JPL."This is the test robot that comes closest to simulating the actual mission operations Perseverance will experience on Mars - with wheels, eyes, and brains all together - so this rover is going to be especially fun to work with."This rover model will be particularly useful for completing a full set of software tests so the team can send up patches while Perseverance is en route to Mars or after it has landed.And just like Perseverance has a fitting name, its twin has a name, too: OPTIMISM, short for Operational Perseverance Twin for Integration of Mechanisms and Instruments Sent to Mars."Optimism" is nearly identical to Perseverance. It is the same size, has the same mobility system, top driving speed of 0.15 kph, and features the same distinctive "head", known as the remote sensing mast.After a second phase of building at the beginning of the new year, it will have the full suite of science instruments, cameras, and computer "brains" Perseverance has, plus its unique system for collecting rock and soil samples, NASA said.When the Perseverance rover launched to Mars on July 30, it carried with it a sophisticated sampling system with drill bits, a coring arm, and sample tubes. Perseverance will collect samples from several spots on Mars for return to Earth.