[music playing] Would you go to Mars?

That's the next planet in line from the sun, in case you weren't sure.

There's so much talk all the time of, let's go colonize Mars.

Let's go explore Mars.

No, I want to be first to live in a bubble by myself.

And all this talk is getting to me, like it's making me think about it.

Would I actually go to Mars?

I don't know.

In order to go through this discussion with me, I interviewed Bill Nye.

Yeah.

I totally played it cool.

Totally.

So here today to talk to me about this crazy idea of traveling to Mars is Bill Nye, and we're here at the Planetary Society.

Bill, thanks for joining me.

Oh, no.

No, no, it is I who must thank you.

Well, you are welcome.

The first question I have to ask you is, what is the obsession with Mars?

Why do people want to go?

First of all, you can see it from here, I guess.

But the main thing nowadays is, for me-- this is for me, scientifically, as a human here on Earth in the cosmos-- is it's reasonable that Mars once supported life, because it used to be very wet.

There used to be oceans and maybe a lake, or 500, on Mars.

So wherever, wherever go on Earth and find even a little bit of moisture, there's something alive.

So my claim is if we were to find something alive on Mars, it would change the course of human history, or evidence of life, like fossil bacteria, Martian microbes, Marscrobes.

It would be huge.

It would be huge.

It would be so huge.

OK, pause.

We have a ton of evidence that Mars used to be covered in oceans.

There's this line all over the entire planet that goes for kilometers, and for awhile scientists didn't know what it was.

They thought maybe it was an ancient shoreline.

Because, OK, so if all of the oceans on Earth suddenly evaporated, it would leave behind, well, first dead fish.

But eventually, after millions of years, just a line, evidence for a shoreline.

And it should be at all the same elevation.

It should be at sea level.

So they thought that maybe this line on Mars was a prehistoric shoreline.

But there was a problem.

The line on Mars has kind of a wobble.

It changes in elevation by a few kilometers.

And if it were shoreline, it should be all at sea level.

So scientists thought, this can't be a shoreline unless there's something that changed the elevation of Mars' shoreline at some point.

Could something change sea level?

Well, scientists in 2007 looked into whether a giant mass redistribution, like that from a growing 13-mile volcano, like the volcano that Mars has called Olympus Mons, and they found that that mass redistribution can cause Mars' spin access to move, and that could change sea level by a few kilometers.

When they added in this giant outcropping of volcanoes on Mars, they got a perfect sea level line.

So this line all over Mars became evidence that one fifth of Mars was once covered in oceans, which is pretty cool.

And that's why I want to explore Mars.

Because if we found evidence of life, it'd change the course of history.

That would be-- I may have said that line.

--incredible.

It would be right on the border of credible.

It'd be amazing.

Yeah.

I probably wouldn't turn down the opportunity to find life on another planet, but first you'd have to get there.

And that's not exactly easy on you, because there's cosmic rays constantly bombarding you in space, trying to give you cancer.

And then zero gravity is super hard on your body.

It takes away your bone density, and your muscle mass, and your strength.

And then when you get to Mars, well, Mars would try to kill you.

What are the ways Mars will kill you when you get there?

You will show up without enough strength to do anything.

Right, because you've just traveled for 300 days.

Your life support system lost water all the way over, so you can't find enough water.

And there's nothing to breathe, so your air maker better work.

Mark Watney, do you know who I'm talking about?

Oh, yeah.

He had an oxygenator.

Right now, though, we don't-- there's no such thing.

You're going to need some technology to allow you to breathe on the planet of Mars.

Yes.

Which I'm not saying is not a solvable problem.

And people on the Space Station are continually working this problem.

And there's always trouble with the "let's make pee back into drinkable water" machine.

It's not saying it can't be done.

It's intuitive.

It sure seems like it should work just great, but there's always some doggone thing.

Right.

So we're not exactly technologically prepared for this kind of trip.

And there are a ton of decisions that key space exploration leaders need to make.

When would we go?

How do we land humans?

And would we just go plop down first on Mars?

People have the idea, let's go land on Mars, set up camps.

It'll be great.

Well, the model we'll give you is the Apollo astronauts who explored the moon.

They orbited the moon first to make sure that it would work, make sure that it-- Without landing.

Without landing.

So you just first do a little orbit.

Oh, a little.

The proper sized.

And that worked.

And so we suggest that this is the same way, the same architecture-- Right.

--for going to Mars is let's orbit first.

And we did a study that you could orbit Mars in 2033 without increasing the NASA budget.

And you can only go to Mars every 26 months, because of the orbits.

So we can only send humans at certain times to Mars, but the same goes for supplies.

Just to support the people.

You know, the Curiosity Rover was huge.

It weighed a ton.

But for a human, you need-- people throw around these numbers-- 30 or 40 tons.

Because you need the life support systems, and you need-- And you need Tang and space food sticks.

That might be an older reference.

But Snickers bars.

Like Thanksgiving dinners.

Yes.

Potatoes.

Yes.

So what everybody who's into this proposes is that we would have a series of rockets, a series of missions, that we'd stage stuff in the Martian orbit, and then you get out there and rendezvous with your stuff, and then you land on-- So it's like squirrels, like they're preparing their nuts for winter.

Yes.

Yeah.

Yes.

And these are big nuts.

Yes.

Yes, they are.

So are we going to Mars to colonize or are we going just to explore?

Bill Nye had something to say about that.

So all this aside, it is an extraordinary place that we very much want to explore, but I don't think it's a place we necessarily want to colonize.

It's two different things.

And I give you Antarctica as the example.

There's a couple hundred people there all the time doing scientific research.

Made very important discoveries.

But you don't go, I'm going to go raise a family on Antarctica.

Nobody says that.

And then the other thing that's really important, and this is really the legacy of "Star Trek," is the prime directive.

We are all sworn not to interfere with other lives in the galaxy.

Starfleet takes the prime directive very seriously.

Which in this show, they did every day.

And it would take 54 minutes.

Do as I say, not as I do.

If there is evidence of living things on Mars, we don't want to contaminate it so that we don't see the living things.

We don't want to bring microbes from Earth, which get mixed in with whatever was going on on Mars, and you can't tell us from them.

We do this planetary exploration for less than $2 billion a year, which you spend-- you buy a cup of coffee, as a taxpayer, you paid for the whole thing.

That's nothing.

Are you excited about going to Mars?

Yes.

Now, I would go to Mars if I'm coming back.

I'm not just going-- Yeah, you want the round trip ticket.

Yeah, heck yes.

So with all this discussion, would I go to Mars?

Despite this childish excitement and wonder inside of me wanting to take me to a different planet, I feel like I just love my life here too much on this planet, on Earth.

And that's such a crazy thought, like, leaving behind your own planet.

Like, no humans have yet left our planet without an intention of returning.

Think about that.

And I would totally buy that memoir, but it's not going to be written by me.

This has been really fun, Dianna.

Thank you.

This has been so much fun.

Check out the Planetary Society, everybody, planetary.org.

Thank you so much for watching, and-- BOTH: Happy physics-ing.