Definitions Astrophysics

Time for Earth to do one full revolution

Precession

Time for Moon to orbit Earth

Official defiition of a planet, International Astronomical Union (IAU)

Mercury

Venus

Earth

Mars

Jupiter

Saturn

Uranus

Neptune

Asteroids

Comets

Stars

Constellations

Stellar cluster

Astronomical Unit (AU)

Light year (ly)

Parsec (pc)

Galaxy

Stable star

Luminosity (L)

Apparent brightness (b)

Stefan-Boltzmann law

If a star has surface area A, temperature T, then the total power emitted (L) is given by...

O
B
A
F
G
K
M

Red (doppler) shift

Blue (doppler) shift

90% of stars on H-R diagram

Giants

Supergiants

White dwarfs

Variable stars

Binary stars

Visual binaries

Eclipsing binaries

Spectroscopic binary

Stellar parallax

Spectroscopic parallax

Second

Standard candle
(Cepheid variables)

Cepheid variable

Apparent magnitude (m)

Absolute magnitude