Happy 20th, Spirit and Opportunity! How the Mars rovers expanded our horizons 

 Spirit and Opportunity landed on Mars 20 years ago this month, kicking off a surface mission that reshaped our understanding of the Red Planet.
 

https://cdn.mos.cms.futurecdn.net/3hgec7iPZccY9eiZWTUCdd.jpg

https://www.space.com/mars-rovers-spirit-opportunity-20th-anniversary