Seven months after landing on the asteroid Bennu in an attempt to collect samples, the American probe OSIRIS-REx has just started its return journey. In his luggage, a precious cargo likely to shed light on the formation of the solar system.
Four years after its launch from Florida, the OSIRIS-REX probe carried out its attempt to sample the asteroid Bennu (500 meters wide) last October. During this maneuver, attempted at more than 330 million kilometers from Earth, the spacecraft descended in a spiral before touching the surface of the object for a few seconds, exploding a little nitrogen gas at the end of its arm. to release material. These pieces of rock and dust were then collected by the sampling head. The goal was to get at least sixty grams. Mission accomplished.
A long journey home
Since October, OSIRIS-REx has remained in the asteroid’s environment, waiting for the right moment to leave the scene. Finally, it was time to leave. At approximately 10:16 p.m. PST on Monday, Lockheed Martin’s mission control room, located in Littleton, Colorado, received confirmation that his ship had successfully fired its main thrusters to move away from Bennu approximately sixteen minutes earlier. Seven minutes later, the spacecraft officially began its long journey home.
This departure sequence was the most important maneuver of the mission since the arrival of the probe in orbit around Bennu in 2018. The goal was to change the trajectory and speed of the spacecraft so that its path crosses that of our planet Earth in two years. During its journey, the probe will circle the Sun twice, traveling more than 2.3 billion kilometers to catch up with Earth.
If all goes as planned, OSIRIS-REx should normally return to Earth on September 24, 2023 to drop off its package in the Utah desert (United States). These will be the largest samples collected by a NASA mission since the Apollo astronauts returned with moon rocks.
A relic of the solar system
Once recovered, the capsule will be transported to the U.S. agency’s Johnson Space Center conservation facility in Houston. Here the samples will be taken for distribution to several laboratories around the world. NASA will also put 75% of these rocks under seal so that future generations can study them with their technologies.
Bennu being a relic almost unchanged for about 4.6 billion years, analyzing his remains with state-of-the-art instrumentation will be able to give us a glimpse of the formation of our system. This material could also contain molecular precursors that may have led to the evolution of life on Earth.