Nasa’s Perseverance rover typically returns evocative images of dusty, dark landscapes, red-hued sandstorms and samples of Martian rock. So its operators were surprised to receive an image on Monday of a shiny silver object resembling an abandoned crusty package wedged between two rocks.
The object, the Nasa team concluded, is a piece of debris thrown from the robotic craft when it landed in February 2021.
“My team spotted something unexpected: It’s a piece of a thermal blanket that they believe may have come from my descent stage, the rocket-powered jet pack that dropped me off on the day of the landing in 2021,” said the Perseverance Twitter account reported.
“This piece of shiny aluminum foil is part of a thermal blanket – a material used to control temperatures. It’s a surprise to find this here: my descent stage crashed at about 2 km. This piece did she land here after that, or was she blown here by the wind?”
The image has rekindled fears that space exploration risks contaminating pristine Martian and lunar environments. The 1967 Outer Space Treaty created an obligation under international law to avoid harmful contamination of outer space, the moon and other celestial bodies, but some argue that the law is not detailed enough to ensure protection.
However, in the case of the Perseverance scope, Professor Andrew Coates, a space scientist at UCL’s Mullard Space Science Laboratory, said: “The good news is that everything is sterilized before going to Mars, and the environment Space radiation helps during the nine month trip to Mars, as does the harsh surface environment.
“Because it is so difficult to land on Mars due to the weak atmosphere, landers always have associated landing system hardware that also lands on the surface – parachutes, tail shells and landing systems – such as the crane celestial for Perseverance and Curiosity, airbags and retro rocket systems for previous missions,” he added. “These ‘fly into the sunset’ from the landing site and end up crashing , but the risk of contamination is very low.”
Avoiding contamination is crucial for missions like Perseverance, which searches for signs of ancient life in Mars’ Jezero Crater. Scientists believe that more than 3.5 billion years ago the area was flooded with water and was home to an ancient river delta. In theory, microbial life could have survived Jezero during this wetter time and so the car-sized rover is collecting soil samples to return to Earth that scientists can assess for signs of ancient life.