Flashcards in 9/10/18 The Size of the Universe / The History of the Universe Deck (16)
diameter of Earth
about 10E4 km
distance from Sun to Earth
distance from Sun to Pluto
size of solar system
If the Sun was the size of aa large grapefruit, how big is Earth; an atom, a ball point, a marble, a golf ball?
a ball point
How many stars does the Milky Way have?
How many galaxies are there?
There are as many stars as what?
Grains of dry sand on all Earth's beaches
radius of the observable universe
14 billion lightyears
Why does the universe expand?
the Big Bang
how are galaxies formed?
gravity pulls matter together
What elements did the early universe contain? (2)
How were the other elements made?
When stars run out of fuel, they explode, scattering the elements into space that they made during nuclear fusion
When 2% of H and He had been converted into heavier elements, what occurred?
the solar system was born
Where was most of the material that makes up the Earth and all life on Earth, including humans, formed?
inside stars that died before Earth formed