the universe Physics

Main sequence stars

Stars that are actively fusing hydrogen into helium and is stable.

Our Location

Earth, Solar System, Orion Arm, Milky Way, Local Group, Virgo Supercluster, Observable Universe.

Red Shift

When light strectches due to its low frequency because it is moving away.

Blue Shift

when light is squashed due to its high frequency because it is moving towards you.

the age of the universe

13.8 billion years olfd

The two pieces of evidence for the Big Bang

1. the stretching of light tells us that the universe is expanding

2. The radiation from the Big Bang

1 Light Year

How far light travels in a year

the speed of light

3 × 10 to the power of 8

Hydrogen Nuclei

the simplest thing in the universe, usually one positively charged proton.

Star Colour

when stars appear blue or red depending on their temperature

Spiral Galaxies

long curling arms, looks like whirlpools, Milky Way

Elliptical Galaxies

Uniform structure, rounded shape

Irregular Galaxies

Twisted shapes, caused by galaxy collisions

Apparent Magnitude

How bright the stars appear from the observable eye

Absolute Magnitude

How bright the stars appear when compared next to eachother

The apparent magnitude of the sun

-27

The apparent magnitude of a full moon

-13

the temperature of red stars

cooler

the temperature of blue stars

hotter

Stars with low temperatures and high luminosity

Red Giants

Black Hole

What the largest stars leave after a supernova explosion. Has densely packed neutrons and very hihg mass, everything collapsing in one point