NASA Asks NAU Astronomer to Find the Right One
David Trilling is vigilantly searching the night sky for asteroids. This associate professor of physics and astronomy at Northern Arizona University is particularly interested in the ones that orbit close to the earth.
“There are about 10,000 known near-earth asteroids and most of those are big. ‘Big’ is bigger than the Skydome, let’s say. And none of those right now have any chance of hitting the earth,” he said. “The problem is there are many, many, many thousand more asteroids bigger than your car that enter the earth’s atmosphere and we don’t know where they are. We don’t have any idea what the risk is of hitting the earth.”
So Trilling is on the first line of defense to alert us, should an asteroid be on a collision course with our planet.
But because he and the astronomers at NAU are the only ones in the world with the skills and resources to measure asteroids, he is on another mission as well. NASA officials have asked him to look for a very specific asteroid, one that they can catch.
“The way they want to capture this thing is they want to send a spacecraft and then put the asteroid in a bag,” said Trilling.
NASA’s idea is to place the spacecraft and the bagged asteroid as a unit into an earth-moon orbit. Then, astronauts could go visit the captured asteroid and bring back pieces to study.
“Scientifically, the ones that are very interesting are the ones that have water and then they might have organic molecules in them,” explained Trilling. “They frequently do have organic molecules, which is a molecule that has carbon in it. And our bodies are made of organic molecules. We know there are meteorites [asteroids that crash into the earth] that have amino acids in them, so the building blocks of life have been found in meteorites and they for sure are out there in some of these asteroids.”
Metals like nickel and platinum also are in some asteroids. Therefore, the possibility of extracting valuable ore from asteroids opens up a whole cosmic field for mining companies.
Another reason scientists are interested in asteroids is to solve a mystery. Trilling says the composition of these rocky bodies in space is different from the composition of those that make it to earth.
“The thing about asteroids that’s really cool is that the universe comes to us. We understand the meteorites really well. We know what they’re made of and we have a good guess of what asteroids are made out of, but there’s this one weird problem that the meteorites don’t look like the asteroids. The compositions look similar, but not exactly the same, and nobody really understands this problem very well.”
But first things first: How do you go about bagging an asteroid?
“Well, the bag is only so big,” said Trilling, “so if the asteroid is too big, it doesn’t fit, no good.”
The right fit, he says, is about the size of a school bus, the same size as the asteroid that exploded above Chelyabinsk, Russia a little more than a year ago.
And when this right-sized asteroid is orbiting near the earth, a spacecraft would be sent to intercept it.
“It’s like catching a baseball,” said Trilling. “You’re playing outfield for the Diamondbacks and somebody hits a fly ball to the far outfield and you have to run back toward the fence and look back over your shoulder and hold out your glove and catch this thing as it drops in.”
If this thing drops in, as NASA projects, it could happen as early as 2023. FBN
