Right now, a spacecraft is carrying a very special delivery to Earth after a years-long voyage to a cosmic destination that can shed light on how life might have first emerged on our planet and how we can protect it from future cosmic hazards.
This enterprising NASA mission, known as the Origins, Spectral Interpretation, Resource Identification, Security, Regolith Explorer (OSIRIS-REx), is returning home with samples it snatched from asteroid Bennu, which is deemed one of the most dangerous space objects known to scientists.
“Bennu is considered a potentially hazardous object because it does have this near-Earth orbit,” Daniella DellaGiustina, an OSIRIS-REx working group lead at the University of Arizona, in an episode of Motherboard’s “Space Show” posted on Wednesday. “There is about a one-in-2,700 chance of an Earth impact late in the next century from Bennu, but OSIRIS REx has really helped to inform our planetary defense efforts.”
In the new episode, DellaGiustina and fellow guests Pierre Haenecour and Andrew Ryan, who are also OSIRIS-REx working group leads at the University of Arizona, delved into the precise measurements and surveys that the spacecraft has captured to better understand Bennu and the threat it might pose to Earth.
They also described the thrilling moment in October 2020 when the spacecraft briefly touched Bennu and grabbed about a half pound of dust and rocks from its surface.
“‘Giddy’ is the first word that comes to mind,” said Ryan as he recalled the day of the sample collection. “We had done everything we could to prepare, the commands were sent to the spacecraft, and it was now or never.”
“We were all kind of watching together at that point and feeling confident but, of course, a little nervous, because there is always a bit of unpredictability,” he added. “We don't know, 100 percent, the true nature of the material on the surface."
Indeed, it turned out that OSIRIS-REx was almost too good at snatching samples, as its collection container got jammed from the huge haul of material it was able to grasp.
Fortunately, the team resolved the issue and closed the container, enabling the spacecraft to safely bring its valuable contents back to Earth, where they will be dropped off in New Mexico in September 2023. A quarter of the samples will be available for immediate analysis, but the rest will be preserved for the benefit of future scientists who will likely have access to better analysis techniques.
“A lot of discoveries are based on not just a new sample availability, but also new technology,” Haenecour said, which is why the team is “ensuring that we preserve the samples for the next generation.”
In this way, OSIRIS-REx may continue to yield insights about our solar system, the origins of life on Earth, and planetary defense for decades, or even centuries, to come.