2.1 Star Magnitudes

Star Magnitudes

Key terms

Light Year - Distance Light Travels through space in a year =9.45*10^15m

Galaxy - Assemblies of stars prevented from moving away from eachother by gravitational attraction. They are a million light years apart separated by empty spaces.

Astronomical Unit - Mean average distance between the centre of the Sun to Earth.

Parallax Angle - angle subtended to the star by the line between the Sun and Earth. Half the angular shift of the stars line of sight over six months. Measured in arc seconds 1degree/3600.

1 Parsec - The distance to a star which subtends an angle of 1 arcsecond…