Avi Loeb

Don't speak, just observe the other side, because it may be different than what you think.

And maybe on one of the dates, you will have a serial killer on the other side.

So we can figure out composition of a plume of gas by taking a spectrum of it, which means you basically have some kind of a prism that breaks, you know, that light with different wavelengths is bent at different angles.

And so you spread the light into the different colors.

And if you do that, you can find the fingerprints, the spectral fingerprints of specific atoms or molecules, because each atom or molecule has transitions.

I actually teach, I taught it just two days ago in a class that I teach that is mandatory, obligatory at the Harvard Astronomy Department.

where I was chair for a decade, like between 2011, 2020.

So this is the mandatory class, and I just taught how spectral lines emitted by atoms and molecules just two days ago.

So this is a very well-known thing, and we know the wavelengths of those, and we use them to identify the composition of...

You know, we know which atoms produce these spectral lines, the fingerprints.

It's just like fingerprints, okay?

And so what was found, you know, and that's by multiple teams.

There are three papers on that.

We found...

A lot of nickel, but very little iron.

At first, no iron whatsoever.

Now, usually in all the comets in the past, from the solar system and also from interstellar space, there is one comet, Borisov, that was found.

It's the second interstellar object, which looked just like a familiar comet.

I had nothing to say about that one.

It looked like a comet, behaved like a comet.