Scientist Thinks Mysterious Interstellar Object is Extraterrestrial

You came on my radar when you were discussing Amua-mua, is that what I said? Yes, that's the right thing. Amua-mua, which is an object that we detected in space that you believe could possibly have been extraterrestrial in origin, meaning from some sort of a civilization. Right. Why did you—please explain to people what Amua-mua is, why it's so extraordinary, and why you think it's possible that it came from some other intelligent civilization. Right. So I'm a scientist, and I basically follow the evidence, just like Sherlock Holmes, trying to find solutions. It's a detective story. You have some anomalies, some things that don't quite match what you expected, and you're trying to find an explanation. The thing about Amua-mua is that it was discovered on October 19, 2017, a little more than three years ago. It was the very first object that visited our vicinity in the solar system from outside the solar system. It moved too fast to be bound to the sun, the very first object that we have found coming to us from interstellar space, from other places. And at first, astronomers said, oh, yeah, it's probably just like the objects we had in our solar system, all the rocks that we have seen before. We have seen comets and asteroids. So a comet is a rock that is covered with ice, water ice. So when it gets close to the sun, the surface gets warmed up, and the ice turns into vapor, gas. And you see this beautiful cometary tail behind it. That's what a comet is. An asteroid is just rock without much ice on it. Actually, the first person to explain what comets are was at Harvard, the university that I am affiliated with. And the story goes that, I mean, it was Fred Whipple that he went to Harvard Square and saw all the slush during the winter day, you know, and came up with the idea that it's just icy rock or icy rocks or rocky ice. And that's what a comet is. And the comets come to us from the periphery of the solar system. And, you know, astronomers said, OK, other stars may have them as well. And, you know, since they are loosely bound, if they are in the periphery, they can be easily ripped apart from their host star. And some of them will fly in our direction. We will see them. So they said, oh, mua mua is probably a comet. The only problem is there wasn't any cometary tail. So you look for a duck, but it doesn't look like a duck, you know. So then the question is, what is it? And so people said, OK, it's just a rock without any ice on it. Then the problem was that it exhibited an extra push away from the sun. And usually you get it from the rocket effect that when you make the cometary tail, it pushes the object in the opposite direction, just like a jet plane. A jet plane works by throwing gas out and that's pushing you forward. So a comet has an extra push when it evaporates. But there was no cometary tail. So why did it show an extra push? That was the key question in my mind, at which point I started thinking, maybe it's not a comet and not an asteroid, something else, you know. And the other strange thing about it, it changes its brightness by a factor of 10 or more. And the brightness of the object, the light that we see is simply reflected sunlight. So just think about it. Think about a piece of paper, razor-thin piece of paper tumbling in the wind. And changing the area that we can see, the projected area of that piece of paper, by a factor of 10 as we look at it, that's exactly what we inferred from this object, spinning around every eight hours, but changing its brightness by a factor of 10, meaning that the area projected on the sky that we see, that reflects sunlight, changed by a factor of 10. It has an extreme geometry, most likely flat, if you try to interpret the light that it reflected over, as it was tumbling around. And so a flat object about the size of a football field that has an extra push, if it were a comet, it needed to lose about a tenth of its weight. So a lot of evaporation. You can't just say, oh, it's a little bit of evaporation, and therefore that's why we don't see it. It should have lost a tenth of its weight. If we go on a diet and lose a tenth of our weight, that's a big chunk of mass, right? So this object didn't lose that because we didn't see it. And the Space Telescope looked very deeply behind it to see if there are any traces of dust or gas, didn't see anything. So then, just like Sherlock Holmes, I was trying to think, together with a postdoc of mine, Schmuel Bialy, what could explain it? And the only thing that came to mind is reflecting sunlight. So the object itself is being pushed by the sunlight reflecting off its surface. And that would agree with everything we know about the object, but in order for it to work, the object needs to be very thin, like a sail, the sail on a boat. So a sail is pushed by a wind, but you can also push an object, a thin object, by light. And that is called the light sail. And we're actually using this technology now, developing it for space exploration. The big advantage is you don't need to carry the fuel with the spacecraft. You just reflect light off it and it's being pushed. There was a science fiction movie that did something like that. I think it was called Sunlight. Quite possibly. I should mention an anecdote. In September, just a few months ago, in September 2020, there was another object that showed an extra push, no cometary tail. And then astronomers gave it a name, 2020SO. Okay, September 2020. And then they extrapolated back in time and found that it came from Earth, actually. And then they looked at the history books and saw that indeed there was a rocket booster from a lunar lander that was kicked into space. And this is the object. Now, why did it show this push? Because it's a hollow, it's a very thin structure. So here is an example where we can tell it's artificial. And we know that we made it, but Oumuamua could not have been made by us because it was passing near us just for a few months. Very quickly, faster than any rocket that we can launch. That's why we couldn't really chase it when it was receding away from us. And it came from outside the solar system. So, you know, I just do one plus one equal two. I say, okay, it looks very peculiar. Maybe it belongs to another civilization. I just put it in a scientific paper. I didn't think, you know, we didn't have any press release. Then it went viral. The public got extremely interested. And the thing that really surprised me is that my colleagues were pushing back. They were very upset that this possibility was even mentioned. You know, we had a seminar, a lecture about this object at Harvard, and a colleague of mine after the lecture said, this object is really weird. I wish it never existed. Now, to me, you know, I was really appalled by this. How can you say something like that? You should be happy about whatever nature gives you. You know, you learn something new. If something doesn't look right, it actually teaches us, oh, it's a learning experience. We learn that we have to revise the way we think about reality, you know. That's a good thing. That's not a bad thing. You shouldn't always be in your comfort zone and think that the future will be the same as the past. So I actually see it as a blessing, you know. I can't imagine why anybody would be upset that it exists. Like, I wish it didn't exist. That's kind of hilarious. Because it takes you away from your comfort zone, you know. I know, but if you're studying the heavens, you're studying the cosmos, what is the ultimate thing that you could find, another civilization or a piece of something from another civilization? That's exactly my point. But if you go back in time, let me give you two examples. Galileo Galilei said, I think the earth moves around the sun. But at the time, philosophers knew for sure that the sun moves around the earth. You see it moving in the sky. It was consistent with their religious beliefs, everything. So they said, we don't want to look through your telescope to change our view. We will put you in house arrest. Now, what did they achieve by that? And by the way, I'm in house arrest, but it's because of the pandemic, not because. So what did they achieve by that? They maintained their ignorance and the earth continued to move around the sun. You know, reality is the one thing that never goes away irrespective of whether you ignore it. You can ignore it. Now, there is another example. There is a student, a student at Harvard, that as a result of my book on this subject that is about to come out in in a week or so, she was inspired to do her PhD. By, you know, on the theme of my book. So she invited me to a thesis exam just a couple of months ago. And one of the examiners, a professor, asked her, do you know why Giordano Bruno, an Italian guy, was burnt at the stake? And she said, well, he was an obnoxious guy. He irritated a lot of people, which is true. You know, he was an obno- But the professor corrected her and said, no, it was because he said that other stars are just like the sun. You know, there are stars like the sun and they have planets like the earth around them and there may be life on those planets. And that was offensive to the church because if there is life there and it had sinned, you know, then Christ should have visited those planets to save them, to save the life, life forms. And, you know, you need multi copies of Christ to visit those planets. And that was unacceptable. So they burned the guy. Burned him alive. So you see that, you know, throughout history, people are not really open minded about the heavens, as you said.