Briefly approach a giant planet next week and grab some rocks and dust from its surface to return to Earth for study. The event marks a major milestone for NASA and a potential boon for our understanding of science, space exploration and the solar system.
A collection of Touch-and-Go (tags) of the asteroid 101955 Bennu is set to go down on Tuesday, October 20th. You need to know about Osiris-Rex, Bennu and how NASA plans to eclipse the planet.
When did the mission start?
Osiris-Rex has existed as a concept since at least 2004, when a team of astronomers first proposed it to NASA. After more than a decade of development, the spacecraft, A joint venture between Lockheed Martin and Boeing topped the United Launch Alliance’s Atlas V rocket. The spacecraft then flew to Benu 26 months later, officially arriving on December 3, 2018.
Since then, the mission team has spent nearly two years around the diamond-shaped space stone, surveying and preparing its specimen to select the best sampling site. In recent months, rehearsals have begun before the next sample collection attempt, and now the team says it is ready to play TAG with Bennu.
Bennu means what is called a “rubble pile” asteroid, i.e. gravity was slowly pushed together with the remains of an ancient collision when it was formed in the deep cosmic past. The result is something like a body-shaped spinning top with a diameter of about a mile (500 m) and large rocks and boulders on the surface.
Bennu is believed to be the window to the solar system’s past: an ancient, carbon-rich body that hindered the formation of both planets and life. Some of these resources, such as water and metals, are suitable for mining at any time in the future on Earth or for space exploration.
The asteroid has another characteristic that makes it interesting to scientists and humans in general – it has the potential to affect Earth in the distant future. Bennu ranks No. 2 on NASA’s list of impact hazards. Current data show dozens of potential effects in the last quarter of the 22nd century, although all of them actually come with a one-minute chance.
How will the tag work?
For anyone who has ever wrestled with robots or entered a robotics competition, the Osiris-Rex mission seems to be the culmination of a young robotist’s dreams. The touch and go sample procedure is a complex, high-stakes task that has been building up at a crucial moment over the years. If it succeeds, it will play a role in history and our future in space.
The original plan is that Osiris-Rex would approach Bennu on a rocky outcrop. The van-size spacecraft will need to negotiate building-size stones around the landing area in order to communicate in a space as large as a few parking spaces. However, the robotic sampling arm will be the only part of the Osiris-Rex that actually comes to the surface. One of the three pressurized nitrogen canisters will run a fire to excite a sample of dust and small rocks that can then be caught in the head of a hand collector to keep it safe and return to Earth.
It will take about four hours to land on the surface of Bennu, about the same time as an asteroid. After this slow approach, the actual TAG sample collection process lasts significantly less than 16 seconds.
Preparations for the tour are not as planned. Mission organizers initially hoped that the surface of Bennu would have plenty of potential landing site, mainly covered with comparable fine material with sand or gravel. It turns out that Bennu’s surface is much rougher than any real welcome landing sites.
After re-evaluating the mission over the past two years, the team decided to try “leading the needle” through the boulder-filled landscape on Nightingale and some other backup specimens. It is still possible that the surface will prove to be very stony to get good samples. If this condition comes out, the team may choose to try again on another site. Osiris-Rex is equipped with three nitrogen canisters to disperse and disrupt the surface, which means that the team makes three attempts to capture the sample.
Immediately after collecting his sample, Osiris-Rex will leave his thrusters behind Bennu. The spacecraft maneuvered the departure the following year and will hang over Bennu until the rest of 2020 before embarking on a two-year journey to Earth.
On September 24, 2023, Osiris-Rex will make its sample return capsule Jetison, which will land in the Utah Desert and be retrieved for study.
Hasn’t this happened before?
Yes. Japan’s Haibusa spacecraft successfully returned to Earth in 2010 with small grains from the planet 25143 Itokawa. His successor, Hayabusa-2, successfullyAnd then received some from the shrapnel. That specimen is currently going to return to Earth.
How to follow the mission
NASA has not yet announced whether it will broadcast the TAG maneuver live, but it looks like NASA TV will take some kind of coverage. We will update this post when we hear more, and in the meantime, follow Osiris-Rex Twitter feed To get the latest updates.