ELLEN STOFAN

Everybody has busy lives, but you can tell people, 'Go outside and look at the night sky. We've been able to demonstrate that every star you see probably has a planet around it.'

Water-based life is very much an Earth-centric view, and we can push the envelope on that here in our own solar system. We have the methane seas of Titan.

The public has an incredible capacity for appreciating the wonder of our planet, our solar system, our universe.

Communication is an issue where we can improve, and if I can do anything to help, I am happy to.

If you think of the Apollo capsule coming into Earth with a parachute, the Mars atmosphere is just so thin, you've got to find some way of slowing yourself down really rapidly.

A lot of my role is advocacy, and as a scientist, you're an advocate, too, because you are coming up with a theory and having to convince your fellow scientists that you're right.

Every time I give a talk, I ask the audience - especially if it's kids - how many want to go to Mars. At least half raise their hands. I don't think there's going to be any shortage of volunteers.

Mars was this water-based planet, and we know there was stable water on the surface for a long time, which is critical for life having a chance to develop.

I wish someone would redo 'Dune.'

I grew up in this business... A lot of my life has been centered around this question about how NASA is helping us to understand our own home planet... and to understand our place in the universe.

We actually look to the scientific community to kind of come back to NASA and tell us what the priorities should be. And then at NASA, we try to look within our budget and say, 'What can we accommodate, and what are the most important things for the nation?'

With the mission to Mars, the whole world wants to get involved. So we actually have 13 different space agencies from around the world working on the global exploration road map.

There's a huge question of whether you really need water for life.

As chief scientist, it's sort of my job to look at bridges between what we do and to see the connections. But when we try to understand how are planets around other stars habitable... to looking back at the Earth - how are the changes that are taking place, how are they going to affect humanity?

As we visit Mars multiple times, we will build up infrastructure on the surface to expand the capabilities and reach of humans on Mars.

Mars missions will require up to three years in reduced gravity, so we need to make sure astronauts can not only survive but thrive as they move outward to explore this new world.

So many people I talk to who work in technology, you ask them, 'What got you interested in science?' and those from my generation say, 'The Apollo landings.'

To unambiguously settle the questions of whether there was life on Mars, it will take scientists down on the surface.

To avoid congestion, I get up at 5:10, grab a slice of raisin toast, and leave the house at 6 A.M. My husband, Tim Dunn, who works for an environmental agency, is still asleep when I slip out, and I find that rather annoying.

Prior to Magellan, due to the fact that we knew it was so hot on Venus, we thought that the rocks at the surface would behave more plastically, more like Silly Putty than like solid rock in the way that we think of it, like the rocks that I'm sitting on.

You see countries like India really investing in their space program because they see it as inspirational and good for their economy.

I live an hour from NASA's HQ in Washington, D.C., and sitting in a jam stresses me out.

As a card-carrying space nerd and NASA's chief scientist, I love space movies, from 'Star Trek' to 'Star Wars' to my all-time favorite - 'The Dish', an Australian comedy that celebrates that first moment when Neil Armstrong stepped down onto the surface of our moon.

One of the big things about space exploration is that it is as expensive as it is complicated, and you need all the countries of the world to help if you want to accomplish big goals.

My key aim is to get man on the surface of Mars by the mid-2030s.