Nebula- a cloud of gas and dust in outer space Protostar- a contracting mass of gas which represents the early stage of formation in a star White Dwarf- a stellar remnant composed mostly of electron-degenerate matter Supernova- transient astromnical event that occurs during th last stellar evolutionary stages of a massive star's life Neutron Stars- a type of compact star Pulsar- a highly magnetized rotating neutron star Black Hole- a region of space-time exhibiting so much gravitational effects that nothing can escape from inside it Spiral Galaxy- flat, rotating disc containing stars, gas, and dust Barred-spiral Galaxy- central bar-shaped structure composed of stars Irregular Galaxy- a galaxy with no distinct, or regular shape Quasar- a massive and extremely remote celestial object, emitting large amounts of energy The Big Bang Theory- a cosmological model that explains the early development of the universe Dark Matter- a hypothetical substance that is believed by most astronomers Dark Energy- unknown form of energy which is hypothesized to permate all of space
