Space physics Flashcards
What is the universe made up of?
Billions of galaxies
What is the galaxy made up of?
Hundereds of millions of stars
What is the milky way made up of?
The sun, 8 planets + dwaf planets that orbit the sun, asteriods + comets that also orbit the sun, Moons that orbit the planets
What was the Sun formed from?
A nebula
What is a nebula?
A cloud of dust and gas pulled together by gravitational attraction
What keeps the core of the sun hot?
Energy made in Nuclear Fusion
What is the stability of the sun resulted from?
The fusion energy trying to expand the sun and gravity acting inwards trying to collapse the sun
What happens to the different size stars?
Small- black dwarf stars
Large- neutron stars
Largest- black holes
What happens during the main sequence of a star?
HYdrogen fuses together to create helium (+ in larger stars lithium)
What happens as a star ages?
More of its mass is converted into energy by nuclear fusion
As the mass decreases, outward forces become larger than the force from gravity
The star then expands + cools becoming a red giant or red super giant
As the star cools and the hydrogen fuel is used up, the outward forces are reduced
The star collapses inwards due to gravity and this causes to increase the temperature once more
It begins to fuse helium + lithium
What was the first element?
Hydrogen
What makes something travel in a circular motion?
A force
What force causes planets to orbit?
Gravity
What happens to an object undergoing circular motion?
The acceleration does not cause the object to change speed
The acceleration causes the object to change direction
The velocity changes but the speed remains the same
The instantaneous velocity is perpandicular to the centripetal force
What do red-shift observations indicate?
All the galaxies in the universe are moving away from one another, the universe is expanding
