Nathalie Cabrol

coming towards the inner solar system and collide with planets.

So you will have more of these impacts if you are too close to the center of the galaxy, not to mention the radiation.

There is a place in our galaxy where it's a really bad neighborhood.

You don't want to be there.

You wouldn't be able to have life.

But what really matters is extinctions, but also the climate history of

of a planet has a role to play.

And it seems that it's a theory.

It still has to be backed up by more observation, but there is a good correlation between not only the passage of the solar system towards the center of the galaxy.

There is one place where we get hit by asteroid because of the interaction I was telling you about.

But the other one is the climate with the Milankovitch cycles.

Big jumps in life's evolution seem to be associated with snowball earth episodes.

We don't know why yet.

Snowball episode, intuitively, you would think that they are connected to a decrease in life because the whole earth is covered in ice.

But for some reason, there were big jumps in evolution right after.

each of those episodes.

And today, there are other things like why all of a sudden you have mutation that seems to be responsible for a big jump in evolution.

We are not clear yet.

So all of those things, when you're thinking about life elsewhere, are going to come into play.

And I cannot tell you that a planet that remains habitable for much longer than the Earth will