astronomy Flashcards
What is the universe
It’s a large collection of billions of galaxies, galaxies is a large collection of billions of stars, our solar system is in the Milky Way galaxy
What is GFS
GFS is how strong something pulls an object towards it
Why is there different GFS on different planets & why does that happen
Earth has a higher GFS than the moon, on earth we are pulled down so much that we can only jumps for a few seconds. On the moon the time you can just for is much longer as it’s pulling you back in with a weaker GF
The earth has more mass than the moon and so has a bigger GFS. Bigger planets than earth will have a bigger GFS
Where else does this happen
Moon orbits the planets
Planets orbit the sun
Comets orbit the sun
Artificial satellites orbit the earth
Differences in Orbits of comets, moons and planets
All have elliptical orbits (rugby balls) Moons orbit planets Comets orbit stars Planets orbit starts Comets have elongated orbits
Stars colour in relation to there surface area temp
The cooler the colour the hotter the star 3500-red 5000-red-orange 7500-yellow-white 10000-white 30000-white-blue 50000-blue
Formation of a Nebula
A star forms from massive clouds of dust and gas in space also know as a nebula. Nebulae are mostly composed of hydrogen,gravity begins to pull the dust and gas together
What is a protostar
Mass grows and star gets hotter a star is formed when it is hot enough for the hydrogen nuclei to fuse together to make helium. The fusion process realises energy which keeps the star hot
Main sequence star
During this stable phase in the life of a star the force of gravity hiking the star together is balanced by higher pressure due to high temps.
What is a red giant
When all the hydrogen has been used up in the fusion process, larger nuclei begin to form and the star may expands to become a red giant
What is a white dwaf
When all the nuclear reactions are over, a small star like the sun may begin to contract under the pull of gravity. In this instance the star becomes a white dwaf
