NASA's OSIRIS-REx today reached its asteroid Bennu, an important step in its mission to sample asteroid and return it to Earth.
OSIRIS-REx was launched on September 8, 2016 from Cape Canaveral. It has five data collection tools, and scientists hope to learn more about the formation of the solar system and even about the resources of an asteroid. Today's milestone marks the end of a two-year journey to Bennu and the beginning of a 1.5-year study phase.
"It took a long time to arrive and we are looking forward to the next chapter of this mission," said Heather Enos, deputy senior investigator for OSIRIS-REx at the University of Arizona, in a NASA press video ,
Today, scientists burned the engines to place OSIRIS-REx safely in orbit around Bennu, 7 kilometers from the asteroid. The spacecraft has been maneuvering since the summer to change its speed and prepare it for this approach and arrival.
Circling asteroids (and rendezvousing with them) is not easy – these rocks have very low gravity and multiple asteroid missions have encountered problems. Bennu will be the smallest astronomical object ever brought into orbit by a spacecraft. On average, it is only about 1,600 feet from end to end. "The low-gravity environment is one of the biggest challenges in carrying out this mission," said Rich Burns, OSIRIS-REx project manager at NASA's Goddard Space Flight Center, in a NASA video. Even the solar energy that heats the spacecraft can change its trajectory.
Asteroids are of great interest to scientists. It is believed that they contain an unaltered record of the early solar system, and it could be the path on which some of the earth's water arrived on our planet. This water or the metals of the asteroid could one day serve as useful resources, so space explorers do not need to bring these heavy materials. And Bennu's orbit makes him a "potentially dangerous" asteroid, which means he's tall and could potentially threaten the earth in the distance, so scientists hope to further characterize him.
Scientists are looking forward to having some real asteroids here analyzing the Earth. "I'm especially looking forward to the moment the sample is retrieved," said Neyda Abreu, a professor of Earth Sciences and Mathematics at Penn State DuBois, to Gizmodo. "We just scratched the surface when it comes to understanding asteroids." Abreu hopes that Bennu will reveal a variety of different materials and terrains, while at the same time providing a safe place to land mission and the largest sample return since Apollo returned lunar rocks. It will hopefully grab up to 2 kilograms of material. However, it is not the first asteroid test – the first "disturbed" Hayabusa mission from Japan brought 1,500 grains of dust from the asteroid Itokawa after considerable difficulty. His predecessor Hayabusa2 is in the middle of his own mission to set up another asteroid, Ryugu.
The OSIRIS REx team will now model the asteroid extremely fine and measure its mass. This will help them determine future orbits and determine where to collect the sample on the asteroid, said Coralie Adams, OSIRIS-REx Flight Navigator, during NASA's press briefing.
The spacecraft is expected to return to Earth in September 2023]