Pictured is a carboniferous asteroid named Bennu.
Eons ago, during the chaotic early stages of the cosmos, our Earth was bombarded by space rocks like Bennu and space debris. Knowledgeable scientists agree that life on Earth was made possible by those early impacts which brought water and carbon and other key ingredients.
Bennu is in the news because we sent a spacecraft there and retrieved a sample. Yay us! Careful analysis in the coming days will tell us much.
Bennu is an object worth studying for its composition but also for another reason. It is described as being as large as the Empire State building, and it’s trajectory indicates it may impact the Earth, possibly as early as 2182. If Bennu does collide with us, it would release 1,200 megatons of energy, 24 times as much as the most powerful nuclear weapon built so far. But no worries! We have our eyes on it.
More cosmic irony! NASA scientists expected the asteroid to be smooth enough for their OSIRIS-REx spacecraft to land. It really wasn’t. The success of the mission to Bennu was only made possible by Brian May, a guitarist for the band Queen. Brian is also PhD in astronomy who specializes in stereoscopic imaging. He turned out to be the hero of the mission when he was able to identify a crater smooth enough for landing.
A billion bravos to the OSIRIS-REx/APEX team on this gigantic achievement.
The surface of Bennu is bombarded with light, solar wind, and cosmic rays. Some of Earth’s atmosphere is lost to space and may include microbes that land on the surface of this near-Earth asteroid. The sampling probe penetrated about a foot and a half. A future mission could sample a deep core for comparison.
To observe is to disturb. The impact of the sample acquisition head broke delicate chemical bonds. The substances in and on Bennu were in near zero gravity but were squeezed with 32 times the force of Earth’s gravity on entry in the sample return capsule. The chamber was designed to keep the sample under 167 degrees F. A major challenge in science is to reduce extraneous variables as far as feasible.
New knowledge leads to new questions. Issac Newton said that he was successful because he stood on the shoulders of giants. Future scientists and technologists will stand on the shoulders of OSIRIS-REx/APEX giants and extend their work perhaps by miniaturizing smart laboratories that can work in and on distant objects without needing sample returns.
Encore!
Thanks for the astute and enlightening follow up, Jim.