JUANA SUMMERS, HOST:
Eight years ago, a meteor believed to be from another solar system arrived on Earth. It entered our atmosphere at over 100,000 miles per hour before exploding into hot fragments and falling into the South Pacific Ocean. Avi Loeb and his team were the first to spot what might be the first interstellar object to reach our planet. He is a professor at Harvard's Center for Astrophysics, and now he is hoping to launch an expedition to find those fragments at the bottom of the ocean and figure out where the meteor came from. Professor Loeb joins us now. Welcome.
AVI LOEB: Thanks for having me.
SUMMERS: Professor Loeb, first of all, why do we suspect that this meteor came from outside of our solar system?
LOEB: Oh, that's very simple. It moved very fast, roughly 40 kilometers per second when it exploded in the lower atmosphere. And from that, we can infer that it was moving much too fast to be bound to the sun.
SUMMERS: Wow. So how exactly do you plan to retrieve these fragments, and how do you know where to look?
LOEB: The government spotted this object using part of a missile warning system. It took a few years for the U.S. Space Command to issue a letter confirming that our assertion that this object came from outside the solar system is correct. The government also released the light curve of the fireball that exploded. From that, we could infer that the material strength of this object was tougher than iron. It's just like mowing the lawn. We are planning to use a sled with the magnet that will scoop a very thin layer off top of the muck. It would be of historic significance because it would be the first time that humans put their hands on the materials from a big object that came from outside the solar system.
SUMMERS: And, Professor Loeb, you have just compared this to mowing the lawn. And I have to say mowing the lawn has never sounded that interesting to me. What do you hope to find when you do this search?
LOEB: The first thing that we will be able to test is whether the object came from outside the solar system because the composition would be different than all the rocks we find in the solar system. But there is also the possibility that it will be made of some alloy that nature doesn't put together, and that would imply the object is technological. My hope, if you ask what my wish is, is that if indeed it's of artificial origin, there was some component of the object that survived. And if it has any buttons on it, I would love to press them.
SUMMERS: So if I understand all of this correctly, the simplest explanation is that this meteor was a big rock. And I know that you run the Galileo Project, which searches for extraterrestrial technology. So I've got to ask you, are we talking about aliens here?
LOEB: We don't have enough evidence to confirm an artificial origin, but at least in the case of the meteor, we're able to scoop the ocean floor and seek that evidence.
SUMMERS: A lot of astronomers say there are far simpler explanations for what we've observed. How do you respond to that?
LOEB: My point is if a cave dweller were to find a cellphone, the cave dweller would argue the cellphone is the rock of a type that we've never seen before. And the only way to find out is to press some buttons on this cellphone and realize that it records your voice; it records your image. Then it will be clear that it is not rock.
SUMMERS: Avi Loeb, Harvard professor of astronomy who proposes to study what might just be the first known object from another star to reach Earth. Thank you so much.
LOEB: Thanks for having me.
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