Quotes About Astrophysics

The intrinsic brightness of theSun is fully 5,000 times as great as if the whole surface were formed of the molten steel just issuing from the Bessemer converter.

an expressive phrase coined by a Princeton mathematician of the last century: "Wormholes in space.

A million million million million (1 with twenty-four zeros after it) miles, the size of the observable universe.

It's the gravity that shapes the large scale structure of the universe, even though it is the weakest of four categories of forces.

one has a singularity contained within a region of space-time known as a black hole.

the physicist John Wheeler once calculated that if one took all the heavy water in all the oceans of the world, one could build a hydrogen bomb that would compress matter at the center so much that a black hole would be created. (Of course, there would be no one left to observe it!)

When you look at the vast size of the universe, and how insignificant and accidental human life is in it, that seems most implausible.

the universe expanded by a factor of 1,000,000,000,000,000,000,000,000,000,000 in .00000000000000000000000000000000001 second. It was as if a coin 1 centimeter in diameter suddenly blew up to ten million times the width of the Milky Way.

The mass of the sun curves space-time in such a way that although the earth follows a straight path in four-dimensional space-time, it appears to us to move along a circular orbit in three-dimensional space.

We also have some evidence that there is a much larger black hole, with a mass of about a hundred thousand times that of the sun, at the center of our galaxy.

region of space-time known as a black hole.

can one have atoms in which the nucleus is a tiny primordial black hole, formed in the early universe?

It is said that fact is sometimes stranger than fiction, and nowhere is that more true than in the case of black holes. Black holes are stranger than anything dreamed up by science-fiction writers, but they are firmly matters of science fact.

If you fall towards a black hole feet first, gravity will pull harder on your feet than your head, because they are nearer the black hole. The result is that you will be stretched out lengthwise, and squashed in sideways.

Today scientists describe the universe in terms of two basic partial theories—the general theory of relativity and quantum mechanics

Corpuri precum stelele sau g?urile negre nu pot ap?rea din nimic. Dar un întreg univers poate.

contains on average some one hundred billion stars. If a star were a grain of salt, you could fit all the stars visible to the naked eye on a teaspoon, but all the stars in the universe would fill a ball more than eight miles wide.

There is a black hole with a mass of about four million times that of the Sun at the centre of our Milky Way galaxy.

black hole has a boundary called the event horizon. It is where gravity is just strong enough to drag light back and prevent it from escaping.

If you fall towards a black hole feet first, gravity will pull harder on your feet than your head, because they are nearer the black hole. The result is that you will be stretched out lengthwise, and squashed in sideways. If the black hole has a mass of a few times our Sun, you would be torn apart and made into spaghetti before you reached the horizon.

FIGURE 3.1 Stars

There are no black holes in the sense of regimes from which light can't escape to infinity.

We're going to be seeing things from regions in the universe where Einstein is the whole story. Newton you can forget about.

Finding the first seed black holes could help reveal how the relation between black holes and their host galaxies evolved over time.