A critical part of NASA's next $2 billion rover mission to Mars broke during testing earlier this month.
The Mars 2020 mission's heat shield was undergoing stress-testing when it developed a crack that appeared around its entire circumference. The shield is designed to protect the rover as it enters the Martian atmosphere.
"The test was designed to subject the heat shield to forces up to 20 percent greater than those expected during entry into the Martian atmosphere," NASA said in a statement. The crack was "unexpected" according to the release, and engineers will have to build a new shield for the mission.
Mars 2020 is intended to send a six-wheeled rover that will look for potential signs for life on the red planet. And it will demonstrate the initial steps needed for a future Mars mission that will return samples to Earth.
The heat shield is a curved structure made mostly out of a lightweight material known as phenolic-impregnated carbon ablator. PICA is as light as balsa wood but can withstand temperatures of nearly 4,000 degrees Fahrenheit as the spacecraft comes screaming into the Martian atmosphere.