Neil deGrasse Tyson
What's the difference between astronomy and astrophysics? Sheila Kaminsky BROOKLYN, N.Y.
There was a day long ago when all you could do to study the universe was pull out a telescope and look up. Physics did not come of age until the late 1800s. Now any modern-day astronomer is also an astrophysicist. We use them interchangeably.
What should be done about the fact that American children lag behind kids in other countries in science and math? Francis Harrington MARLBOROUGH, MASS.
We need to do something about the stigma. Somehow it's O.K. for people to chuckle about not being good at math. Yet if I said I never learned to read, they'd say I was an illiterate dolt. You can't look at science and math as separate. They're fundamental to what it is to be alive because they're all around us.
Which area of astrophysics interests you the most? Sandra Wright, CHESTER, N.J.
I'm fascinated by the deaths of stars and the havoc they wreak on their environments. As a public scientist, I like the subjects the public likes: the search for life, NASA missions, black holes, the Big Bang.
Do you believe in the possibility of extraterrestrial life? Peter Bryan Torres NEW YORK CITY
Anyone who has studied the problem recognizes the likelihood that there's life elsewhere in the universe. Now, if you want to say that there is life out there that is intelligent and built a flying saucer and traversed the galaxy to come here and land on Earth and be spotted by people who see lights in the sky ... okaaay.
What is your favorite part of the work you do? Laura Essel, AKRON, OHIO
When someone comes up to me with a question about the universe. And I reply. And I see the person's eyes light up because they learned something new.
You talk about events that can cause the end of the world. Does this keep you up at night? Carlos Sell SAN JOSÉ, COSTA RICA
Yes! If it doesn't keep you awake at night, what's wrong with you? However, it might keep me awake in a different way. I think of ways to prevent them from happening.
How long do you think it will be until we colonize other planets? Antonio Jones, PHILADELPHIA
Do you know that Antarctica is balmier and wetter than the surface of Mars? Yet I don't see people lining up to build condos in Antarctica. So how long? A thousand years. Never. We can visit them. But to land there and say, "What an oasis!"--not anytime soon.
If you could meet any scientist who ever lived, who would it be? Larry Bassett THORNWOOD, N.Y.
Isaac Newton. No question about it. The smartest person ever to walk the face of this earth. The man was connected to the universe in spooky ways. He discovered the laws of motion, the laws of gravity, the laws of optics. Then he turned 26.
What is your favorite science-fiction movie, and in that movie, what science is plausible? Rohit Sang, NEW YORK CITY
Deep Impact and Contact. They spent a lot of time getting the science right. I'm on a crusade to get movie directors to get their science right because, more often than they believe, the science is more extraordinary than anything they can invent.
Do you think that man is fully capable of understanding the universe's design? Byron Lendl Ong, MANILA
I lose sleep at night wondering whether we are intelligent enough to figure out the universe. I don't know.
Video at Time.com To watch a video interview with Neil deGrasse Tyson and to subscribe to the 10 Questions podcast on iTunes, go to time.com/10questions