NASA has set the timeline for the departure and return of its OSIRIS-REx spacecraft, which will carry with it precious surface samples from the asteroid Bennu for laboratory analysis back on Earth. Prior to making the return journey, the probe will conduct one final close flyby of the wandering solar system body to make observations of the impact site from which the samples were taken.
Since the advent of modern astronomy, humanity has made phenomenal strides in understanding how our solar system came to form, however much of this process remains shrouded in uncertainty.
One method by which scientists are hoping to shed light on the creation processes is to obtain a material sample from one of the many asteroids orbiting the Sun, and return it to Earth. Asteroids are essentially chunks of leftover material dating back to the period in which the planets coalesced.
By transporting a sample of this ancient material and analyzing it in a laboratory setting, it is hoped that scientists will be able to deduce the history of the asteroid from which it was taken, and in so doing shed light on the processes that shaped the solar system as we observe it today.
On September 8, 2016, NASA launched the Origins, Spectral Interpretation, Resource Identification, Security, Regolith Explorer (OSIRIS-REx) spacecraft, which had the ambitious mission of rendezvousing with, and retrieving a sample from the wandering asteroid Bennu.
It is estimated that Bennu has been orbiting largely undisturbed for billions of years, and that it likely formed within the first 10 million years of our solar system’s history. After over two years travelling through the interplanetary void, OSIRIS-REx was finally able to catch up with the comet, and began the process of characterizing the alien body with the goal of isolating a suitable landing spot from which to collect the material sample.
On October 20 last year, OSIRIS-REx successfully descended to the surface of Bennu, and extracted material from the asteroid’s rocky exterior. NASA believes that, following an analysis of data collected during and after the operation, that the probe was able to collect over 2 oz (60 g) of debris, which was the mission sample target.
With this extremely hazardous section of OSIRIS-REx’s mission receding in the rearview mirror, NASA is now looking forward to bringing the spacecraft, and its precious cargo, back to Earth.
In a recent statement, the agency outlined the timeline for OSIRIS-REx’s eventual return. The spacecraft is now slated to leave Bennu on May 10th this year. It will then spend a little under two years and three months in interplanetary space before finally rendezvousing with Earth and detaching the sample return capsule.
"Leaving Bennu’s vicinity in May puts us in the 'sweet spot,' when the departure maneuver will consume the least amount of the spacecraft’s onboard fuel," comments Michael Moreau, OSIRIS-REx deputy project manager at NASA’s Goddard Space Flight Center, Maryland. "Nevertheless, with over 593 miles per hour (265 meters per second) of velocity change, this will be the largest propulsive maneuver conducted by OSIRIS-REx since the approach to Bennu in October 2018."
Prior to leaving Bennu, OSIRIS-REx will undertake a final close flyby of Bennu, during which the probe will image the sample site in order to see how the touchdown has altered the asteroid’s surface.
Source: NASA