WASHINGTON: NASA’s first mission to retrieve an asteroid sample and return it to US soil is expected to reach a perilous finale on Sunday (Sep 24) 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 of 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 9am local time (11pm, Singapore time), at a military testing site in the western state.
Some four hours earlier, at about 108,000km 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 43,000kmh and reaches a maximum temperature of 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 650 sq km 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.
“Sample return missions are hard. There’s a number of things that can go wrong,” said Sandra Freund, Lockheed Martin’s OSIRIS-REx program manager.
Teams have meticulously prepared for the capsule’s return – even a “hard landing scenario” according to Freund – in order to preserve the asteroid material in its pristine form.
A final dress rehearsal took place in August, with a replica capsule dropped from a helicopter.
Source: CNA
