Nasa spacecraft touches asteroid surface to return alien samples to Earth

In a historic event that unfolded nearly 321 million kilometers away from the Earth, a Nasa spacecraft successfully touched the surface of an asteroid to collect pristine samples to return to the Earth. The OsirisRex mission performed a first-of-its-kind Touch and Go (TAG) manoeuvre to blast nitrogen to gather regolith (dust and minerals) from the surface of asteroid Bennu. 

“This amazing first for Nasa demonstrates how an incredible team from across the country came together and persevered through incredible challenges to expand the boundaries of knowledge,” said Nasa Administrator Jim Bridenstine, adding, “our industry, academic, and international partners have made it possible to hold a piece of the most ancient solar system in our hands.”

On the midnight of Tuesday-Wednesday, the spacecraft began its descent out of the asteroid's orbit where it had been for nearly two years. After a four-hour descent at an altitude of approximately 410 feet, the spacecraft precisely targeted the sample collection site Nightingale extending the shoulder, then elbow, then wrist of its 11-foot sampling arm, known as the Touch-And-Go Sample Acquisition Mechanism (TAGSAM). 

It continued its descent coasting past a boulder the size of a two-story building, nicknamed “Mount Doom,” to touch down in a clear spot in a crater on Bennu’s northern hemisphere. The size of a small parking lot, the site Nightingale is one of the few relatively clear spots on this unexpectedly boulder-covered space rock.

. The mission’s target is Bennu, a carbon-rich near-Earth asteroid that is also potentially hazardous to Earth. (Source: Nasa)

 

“After over a decade of planning, the team is overjoyed at the success of today’s sampling attempt,” said Dante Lauretta, OSIRIS-REx principal investigator at the University of Arizona in Tucson. “Even though we have some work ahead of us to determine the outcome of the event – the successful contact, the TAGSAM gas firing, and back-away from Bennu are major accomplishments for the team. I look forward to analyzing the data to determine the mass of the sample collected.”

While the mission has been a success so far, it will take about a week for the OSIRIS-REx team to confirm how much samples the spacecraft collected. The goal is to gather at least 60 grams of alien surface material. 

Since the distance between the Earth and Asteroid Bennu is over a million km the commands to execute the TAG were pre-programmed into the system. “Our first indication of whether we were successful in collecting a sample will come on October 21 when we downlink the back-away movie from the spacecraft,” Nasa quoted Michael Moreau, OSIRIS-REx deputy project manager as saying. 

NASA’s OSIRIS-REx mission is the first mission to retrieve a pristine sample of an asteroid and return it to Earth for further study. (Source: Nasa)

Scientists will verify the success of the mission on October 22 as they snap images of the TAGSAM head to see whether it contains Bennu’s surface material followed by a spin maneuver on October 24 to determine the mass of the collected material. If unsuccessful, the spacecraft has enough pressurised nitrogen for two more attempts in January 2021.

Bennu is a diamond-shaped pile of rubble floating in space, but there’s more to it than meets the eye. The asteroid is just one of the nearly 780,000 asteroids in our solar system, but what makes it unique and appealing is its proximity to the Earth. A well preserved time capsule from the early solar system, scientists suspect that microscopic grains of dust on the surface could be the same ones that spewed from dying stars which coalesced to make the Sun and the planets nearly 4.6 billion years ago. 

The spacecraft is set to deliver the asteroid sample to Earth on September 24, 2023.