OSIRIS-REx orbits less than one kilometer from Bennu
– News of June 18, 2019 –
The solar system continues to reveal its secrets. Comets and asteroids are exploration targets increasingly studied by space agencies. NASA has thus dedicated the OSIRIS-REx space probe to the asteroid Bennu, a Type C near-Earth object of about 500 meters in diameter. It is thought to be a planetoid fragment that was destroyed during the violent history of our solar system. The American space probe will conduct a sampling later in its mission.
But before, OSIRIS-REx is getting closer to Bennu. On June 12, the US space probe maneuvered to lower its orbit. It is now less than 700 meters from the surface of the asteroid. This is the lowest orbit ever reached by a space probe. The purpose is to select four potential sites for sample collection. NASA also wants to use this small distance to elucidate a mystery.
Indeed, Bennu has a strange behavior. He regularly throws dust into space. The scientific team of the mission is surprised by this phenomenon. The horizon of the asteroid will be photographed regularly in the coming weeks to try to highlight these ejections and perhaps understand them. In the middle of August, OSIRIS-REx will resume a little altitude to continue its observation. In July 2020, the space probe will take a small piece of the asteroid before bringing it back to Earth.
The US space agency is however far from having completed the exploration of asteroids. It prepares two ambitious missions. Lucy will be the first space probe to explore the Trojan asteroids of Jupiter. It will take off in October 2021 to fly over many targets. In 2022, the Psyche mission will be launched.
OSIRIS-REx approaches Bennu
– News of December 4, 2018 –
NASA mission OSIRIS-REx has arrived near the asteroid Bennu. For the moment, the spacecraft has not launched into the orbit of the asteroid, it is flying alongside it on a similar trajectory. The space probe will go into orbit of the asteroid on December 31st.
The main mission of OSIRIS-REx is a return of samples, such as what the Japanese space probe Hayabusa 2 is doing on the asteroid Ryugu. It will however be necessary to wait until 2023 before being able to analyze this precious sample of asteroid in the terrestrial laboratories.
In the meantime, the spacecraft will start its study and mapping work to select the best sampling site possible. OSIRIS-REx also has the mission to determine the resource potential of an asteroid, which could interest future miners and explorers.
OSIRIS-REx and Hayabusa 2 approach their goals
– News of September 18, 2018 –
Two space missions will take their samples on asteroids this year. These two missions have similar goals and schedules. This is the US mission OSIRIS-REx and the Japanese mission Hayabusa 2. These two missions have been in the news in recent days as they advance on their objectives.
OSIRIS-REx was able to take a first series of pictures of its target, the asteroid Bennu. The probe is still 2.3 million kilometers away from the asteroid, it will take a few more weeks to get close to the asteroid. OSIRIS-REx is expected to arrive near Bennu on December 3rd. Before taking a sample of the asteroid, the space probe will spend a year studying Bennu. Accurate mapping will make it possible to choose the better site to take the sample. Once its valuable cargo is stored, OSIRIS-REx will make the return journey to Earth. It is necessary to wait until September 2023 to be able to analyze this sample in terrestrial laboratories.
The Japanese spacecraft Hayabusa 2 has arrived in the vicinity of the asteroid Ryugu. The Japanese mission is very ambitious because it must also drop rovers, a lander and bombard its target with an impactor. These operations should begin soon. The JAXA has scheduled to drop the rovers on September 21 and to drop the Franco-German lander called Mascot on October 3. For this, the Japanese space agency had planned a general rehearsal of operations. But the JAXA announced on September 12 that everything has not gone as planned.
The maneuver was to bring the probe 30 meters above the target. Arrived at 600 meters above the Ryugu asteroid, the Hayabusa 2 probe could not measure its altitude correctly. The distance measuring instrument with a laser has difficulties with the black surface of the asteroid, which apparently absorbs a little too much light for this instrument. The probe is perfectly functional but the method of approach is to be reviewed. The first serie of studies on the asteroid has already identified some of its characteristics, including an estimated mass of 450 million tons. This is enough for there to be a small gravity on the asteroid, which would be enough to bring down lander and rovers in free fall to the surface. It is hoped that JAXA will quickly solve the altimetry problems. Meanwhile, Hayabusa 2 has already sent beautiful pictures of Ryugu on which we can even see the shadow of the probe.
NASA/Goddard/University of Arizona [Public domain]
