The boundary between space and the earth is purely arbitrary. And I'll probably always be interested in this planet - it's my favorite.

Carl Sagan

Carl Sagan

Profession: Astronomer
Nationality: American

Some suggestions for you :

The most brilliant youngsters are a national and a global resource.

Voyages to the outer solar system are controlled from a single place on the planet Earth, the Jet Propulsion Laboratory (JPL) of the National Aeronautics and Space Administration in Pasadena, California.

In science we may start with experimental results, data, observations, measurements, ‘facts'. We invent, if we can, a rich array of possible explanations and systematically confront each explanation with the facts.

The nature of life on Earth and the search for life elsewhere are two sides of the same question—the search for who we are.

I'm frequently asked, Do you believe there's extraterrestrial intelligence? I give the standard arguments—there are a lot of places out there, the molecules of life are everywhere, I use the word billions, and so on.

I am tormented with an everlasting itch for things remote. I love to sail forbidden seas … To the ancient Greeks and Romans, the known world comprised.

The way to find out about our place in the universe is by examining the universe and by examining ourselves - without preconceptions, with as unbiased a mind as we can muster.

Of course we all would like to foretell the future and make contact with the gods.

If we know only our own side of the argument, we hardly know even that; it becomes stale, soon learned only by rote, untested, a pallid and lifeless truth.

Would you say, Billy, be home by the time the Earth has rotated enough so as to occult the Sun below the local horizon? Billy would be long gone before you're finished.

You are worth about 3 dollars worth in chemicals.

A celibate clergy is an especially good idea, because it tends to suppress any hereditary propensity toward fanaticism.

An oak tree and I are made of the same stuff. If you go far enough back, we have a common ancestor.

I do not imagine that many people in the fifteenth century ever wondered if they were living in the Italian Renaissance.