NASA has confirmed that its OSIRIS-REx space probe has left the asteroid Bennu after more than two years of study. In fact, OSIRIS-REx reached Bennu on December 3, 2018. In addition to the data collected with its instruments, OSIRIS-REx will bring back to Earth a capsule containing the Bennu samples collected on October 20, 2020. The return journey will be long because the arrival is scheduled for September 24, 2023.
The route for the return of the OSIRIS-REx space probe to Earth – but to be precise it should be said to the Earth’s orbit – has been designed to save the fuel onboard. There’s no risk to run out of fuel, indeed there’s still plenty of it, to the point that NASA is studying a possible second mission to another asteroid. It will still take some months to know the decisions regarding this possibility.
Meanwhile, the OSIRIS-REx space probe has conducted the first maneuvers to leave the asteroid Bennu. The route makes an orbit around the Sun with a progressive approach to the Earth. During its mission near Bennu, the thrusters were used carefully to get close to and far from the asteroid. To leave Bennu, the thrusters burned at full throttle for seven minutes to reach the speed necessary to begin the long pursuit of Earth.
When the OSIRIS-REx space probe reaches Earth’s orbit, the capsule containing the samples from the asteroid Bennu will be dropped and parachuted over an area of Utah. The data collected by the OSIRIS-REx instruments are essential to know the characteristics of Bennu but only on Earth, it’s possible to carry out in-depth analyzes of the materials that compose it.
Analyzing materials that remained almost unchanged since the formation of the solar system is useful to better understand the history of the formation of asteroids but also of planets. Knowing better the asteroids is also useful for better understanding their potential danger to the Earth and their potential usefulness for the presence of minerals that could be collected in future mining operations. For these reasons, Bennu’s studies will continue in various ways for many years.