Define Flashcards
Black hole
Gravity so strong NOTHING can escape it. A massive star collapses under its own gravity after running out of nuclear fuel.
Big Bang
An extremely hot and dense explosion that caused the development of the universe
Doppler effect
Change in frequency or pitch in a wave: if closer together, the frequency increases (higher pitch); if further apart, the frequency decreases (Lower pitch)
Galaxy
A large system of stars, gas, dust, and matter are all held together by the galaxy.
Light Year
Unit used to measure the distance light travels in a year.
Main sequence
Stable phase of the life cycle. It fuses hydrogen into helium in its core.
Nuclear fusion
Process by which stars generate heat and light by combining hydrogen atoms to form helium in their cores.
Nebula
Birthplace of stars, as particles within them come together under gravity to form new stellar bodies. Formed by dust and gas.
Red-shift, blue-shift
When an object move away, the wavelengths become longer which shifts to the red spectrum. when a object is moving closer, wavelengths become shorter shifting to a blue spectrum.
Supernova
luminous explosion at the end of a stars life cycle. When a star exhausts its nuclear fuel and its core collapses under gravity.
Biosphere
part of earth where life exists
Atmosphere
layer of gasses surrounding earth
Hydrosphere
all water found on, under or above the planet
Lithosphere
outer layer of the earth, like the crust or upper part of the mantle.
Greenhouse effect
certain gasses in earth’s atmosphere trap heat from the sun
