The spacecraft of NASA is arriving at the asteroid called Bennu, in order to collect some samples which are going to tell us something more about life origins.
After a two billion kilometer chase, the spacecraft of NASA, called OSIRIS-REx, finally caught up with the Bennu asteroid.
This intrepid SUV-sized probe was soaring throughout space for more than two years. On the 3rdof December, one week after the space agency landed its spacecraft on the planet Mars, it reached the desired target: a huge rock, with the shape of a diamond, and with a diameter as huge as the Empire State Building, which floats 122 million kilometers from the planet Earth. As of the 31stof December, the probe now successfully orbits the asteroid.
The mission of NASA is to gather some samples from this ancient asteroid, called Bennu, and return those samples to the Earth. The scientists really hope that these space rocks are going to give us some clues about the way life started here, on the planet Earth.
The operation was also quite risky. After the spacecraft’s triumphant arrival, Dante Lauretta, who is the principal investigator, posted a tweet in which he said that the team or OSIRIS is relieved, anxious, and proud to start with the exploration.
Subsequently, on the 31stof December, the spacecraft successfully entered the orbit zone of Bennu, which wasn’t an easy step at all. The OSIRIS-REx was moving at a worrying 10cm per second relative to Bennu.
Heather Enos, the deputy principal investigator, previously warned:
“Manoeuvring around a small body that basically has no gravity is a very challenging endeavor. So we do have to get a little more information to proceed every step of the way.”
Bennu is almost 5% the Mt. Everest’s mass, which sounds quite big. However, in terms of space, it is pretty small, and it generates weak or poor gravitational attraction. In fact, this means the orbit of the spacecraft could be alerted even by the tiniest touch, such as sunlight. Also, the probe will need to travel through the so-called terminator zone, the place where the day meets the night, keeping the solar radiation continuous, in order to avoid the frazzling hopes of NASA of a fixed orbit.
Finally, right after eighteen months of going around Bennu, the spacecraft OSIRIS is eventually going to swing down to the rocky surface of the asteroid, in order to collect all the samples. A robotic arm, long three meters, will hover up about 60g of dust and rocks in just five seconds, right before it slingshots back on our planet, together with the precious cargo it will take.
Despite the origins of life, the space agency expects that the samples are going to tell us something more about asteroids’ make-up, with the view of using the oxygen and hydrogen inside them for one day as the fuel for the passing of OSIRIS.
The time of OSIRIS with the asteroid is probably going to increase our understandings of the effect of Yarkovsky – a non-gravitational and mysterious force which is able to alert an asteroid’s orbit. Scientists hope that shedding some light on these phenomena is going to improve the asteroid-effect forecasts.
How long will we need to wait for the answers?
OSIRIS is supposed to drop the samples on our planet somewhere after five years from this time, with a sample capsule which will touch down on the 24thof September, 2023, in Utah.
For those of you that think that this is a too long period for waiting for the answers, there is a similar mission in Japan which is underway on Ryugu, another asteroid which is two times bigger than Bennu. Also, the samples from this asteroid will be quite smaller and can provide less information that the rocks of OSIRIS; however they are supposed to re-enter the atmosphere somewhere in 2020.
But, for those of you that really cannot wait for Bennu’s fragments to come, you have to be really careful with your wishes: this asteroid is supposed to pass quite close to our planet in about 150 years. This is too close, with a one in 2,700 chance that it is going to collide with our planet.
However, until then, the scientists are going to enjoy the discoveries of OSIRIS-REx over the following several years.
As the principal investigator Dante Lauretta stated:
“The exploration of Bennu has just begun. The best times are ahead of us, so stay tuned!”
Image Credit: NASA
