Here is an I2M Web Portal search result for "Mars" that provides information on the historical development of the Mars exploration program. The Perserverance space craft rover is off to Mars today (July 30, 2020), an acquisition signal has been received, and is now expected to arrive and land on Mars in about 7 months (February 18, 2021).
The internal power is produced by nuclear batteries, designed to last about 14 years. These power sources and other matters were discussed in a 2013 Chapter 9 of Memoir 101 produced by the Energy Minerals Division of AAPG: http://www.i2mconsultants.com/downloads/corp/Memoir101CHAPTER09Rev.pdf
URL: http://i2mportal.com/search_resource.php?search_value=Mars&sort=date#page=1
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Managed & Built by I2M Consulting, LLC | © 2010-