NASA's next Mars rover mission is potentially delayed due to a crack that formed in the rover's heat shield.
The Mars 2020 rover, scheduled for launch in July 2020, is equipped with upgraded technology, including a heat shield that is meant to protect it during its descent through the Martian atmosphere. It is designed to withstand approximately 4,000 degrees Fahrenheit. While undergoing testing, it formed a crack that spread across the circumference of the rover.
Replacing the shield is an obvious financial setback, but could also postpone the launch date, depending on what caused it to crack. According to NPR, developers at Lockheed Martin, along with NASA engineers, are examining the shield and may end up making changes to its design. Although NASA seems sure that the replacement shield will not prolong the Mars 2020 rover departure, a recent complication with the new James Webb Space Telescope has delayed its launch by almost a year.
Mars 2020 rover's shield is made of phenolic impregnated carbon ablator (PICA), which has been successfully used on other atmospheric entry missions, such as SpaceX's Dragon. The material is both lightweight and heat resistant, making it an ideal option. The following video from NASA's Ames Research Center explains how this heat shield material works: