AFP :
NASA’s first mission to retrieve an asteroid sample and return it to US soil is expected to reach a perilous finale on Sunday with a descent into the Utah desert.
Scientists hope the material — possibly the most ever retrieved by such a mission — will provide humanity with a better understanding on the formation of our solar system and how Earth became habitable.
The US space probe OSIRIS-REx, launched in 2016, scooped up the sample from an asteroid called Bennu almost three years ago.
Touchdown is scheduled for Sunday at around 9:00 am local time (1500 GMT), at a military testing site in the western state.
Some four hours earlier, at about 67,000 miles (108,000 kilometers) away from Earth, the Osiris-Rex probe will release the capsule containing the sample.
The final descent lasts 13 minutes: the capsule enters the atmosphere at a speed of around 27,000 miles (43,000 kilometers) per hour and reaches a maximum temperature of 5,000 degrees Fahrenheit (2,800 degrees Celsius), NASA said.
If all goes well, two successive parachutes will bring the capsule to a soft landing on the desert floor, where it will be retrieved by prepositioned staff.
Hitting the target area of 250 square miles (650 square kilometers) is like “throwing a dart across the length of a basketball court and hitting the bullseye,” Rich Burns, OSIRIS-REx project manager at NASA, told a press conference last month.
The night before landing, controllers will have a final opportunity to abort if conditions are not correct.
If so, the probe would then circle the Sun before its next attempt — in 2025.