Question

1)How did the universe begin? What happened during the Big Bang?

2)How do we measure a galaxy's distance?

3 ) What is a black hole?​

Answer 1

Answer:

1) That means billions of years ago, everything in the universe was contained in a tiny ball that exploded! ... The Big Bang was the moment 13.8 billion years ago when the universe began as a tiny, dense, fireball that exploded. Most astronomers use the Big Bang theory to explain how the universe began.

2) Astronomers can use what are called surface brightness fluctuations (SBF, for short), along with the color of a galaxy, to calculate how far away it is from earth. Most galaxies measured in this way are millions of light years away.

3) black hole is a region of spacetime where gravity is so strong that nothing—no particles or even electromagnetic radiation such as light—can escape from it. The theory of general relativity predicts that a sufficiently compact mass can deform spacetime to form a black hole