angle

meteorite

angular diameter (angular size)

model

angular distance

nebula (plural nebulae)

arcminute (', minute of arc)

Newtonian mechanics

arcsecond (?, second of arc)

parsec (pc)

astronomical unit (AU)

power of ten

Big Bang

powers-of-ten notation

black hole

pulsar

degree (°)

quasar

exponent

scientific method

galaxy

*SI units

hypothesis

*small-angle formula

kiloparsec (kpc)

solar system

laws of physics

subtend (an angle)

light-year (ly)

supernova (plural supernovae)

megaparsec (Mpc)

theory