1. Black holes can
be best described as a sort of vacuum, sucking up everything in space.
Scientists have discovered that black holes come from an explosion of huge
stars. Stars that are near death can no longer burn due to loss of fuel, and
because its temperature can no longer control the gravitational (重力的) force,
hydrogen ends up putting pressure onto the star's surface until it suddenly
explodes then collapses. 2. Black holes come from stars that
are made of hydrogen, other gases and a few metals. When these explode it can
turn into a stellar-mass (恒星质量) black hole, which can only occur if the star is
large enough ( should be bigger than the sun ) for the explosion to break it
into pieces, and the gravity starts to compact every piece into the tiniest
particle. Try to see and compare: if a star that's ten times the size of the sun
end up being a black hole that's no longer than 70 kilometers, then the Earth
would become black hole that's only a fraction of an inch! 3.
Objects that get sucked in a black hole will always remain there, never to break
free. But remember that black holes can only gobble up (吞噬) objects within a
specific distance to it. It's possible for a large star near the sun to become a
black hole, but the sun will continue to stay in place. Orbits (轨道) do not
change because the newly formed black hole contains exactly the same amount of
mass as when it was a star, only this its mass is totally contracted that it can
end up as no bigger than a state. 4. So far, astronomers have
figured out that black holes exist because of Albert Einstein's theory of
relativity. In the end, through numerous studies, they have discovered that
black holes truly exist. Since black holes trap light and do not give off light,
it is not possible to detect black holes via a telescope. But astronomers
continue to explore galaxies (银河系), space and the solar system to understand how
black holes. It is possible that black holes can exist for millions of years,
and later contribute further process in galaxies, which can eventually lead to
creation of new entities. Scientists also credit black holes as helpful in
learning how galaxies began to form.
填空题
Paragraph 1 ______?
A. What are black holes made of
B. Is there proof that black holes really exist
C. How were black holes named
D. How are black holes formed
E. What are different types of black holes
F. What happens to the objects around a black hole
填空题
Paragraph 2 ______?
填空题
Paragraph 3 ______?
填空题
Paragraph 4 ______?
填空题
Black holes are formed after ______.
A. a fraction of an inch B. the creation of new entities
C. the same amount of mass D. the tiniest particle
E. an explosion of huge stars F. the existence of black holes
填空题
When a large star explodes, the gravity compacts ever piece into ______.
填空题
A newly formed black hole and the star it comes from are of ______.
填空题
Albert Einstein's theory of relativity helps to prove ______.