Exploration Quote by John M. Grunsfeld

“Asteroids are craggy chunks of rock. Comets are balls of dirt, ice, and frozen gases. And meteors are, quite simply, whatever falls through and…

— Neil deGrasse Tyson

Just as the system of the sun, planets and comets is put in motion by the forces of gravity, and its parts persist in…

— Isaac Newton

Luckily, there are some rocks left over from our earliest days, asteroids formed during our solar system's birth. Occasionally, some of them drop in…

— Neil deGrasse Tyson

Just because Pluto or comets aren't as big as Jupiter doesn't mean they are not scientifically important - indeed, just the reverse is often…

— Alan Stern

I love studying asteroids because they are relatively simple, just rocks in space. They can be understood with physics and described with elegant equations.…

— Carrie Nugent

Our solar system is actually a wild frontier, teeming with different, diverse places: planets and moons, millions of objects of ice and rock.

— Carrie Nugent

Look at that! If you ever needed convincing that we live in the solar system, that we are on a ball of rock, orbiting…

— Brian Cox

If you get asteroids about a kilometer in size, those are large enough and carry enough energy into our system to disrupt transportation, communication,…

— Neil deGrasse Tyson

Once you've got the makings of a star, gravity draws leftover gas and dust into a giant swirling disk. The dust continues to stick…

— Neil deGrasse Tyson

Asteroids have hit the Earth millions of times. We can see them as shooting stars every night. When they get bigger, things get complicated.…

— Rusty Schweickart

Talk about celestial bodies.

— Jackson Browne

What is there in places empty of matter? and Whence is it that the sun and planets gravitate toward one another without dense matter…

— Isaac Newton