[space] big bang theory

Big Bang Theory

The universe is always expanding after exploding suddenly from a very small and extremely hot and dense region, space, time and matter were created.

Electromagnetic Spectrum

The range of wavelengths of radiation produced by the Sun and other sources, arranged in order of frequency and wavelength.

Doppler Effect

A change in sound frequency caused by motion of the sound source, motion of the listener, or both.

Sound moving towards observer...

wavelength (λ) shorter, frequency (f) higher

Sound moving away from observer...

wavelength (λ) longer, frequency (f) lower

Blue Shift

When an object, such as a star, is travelling towards Earth, the wavelength of light observed decreases while frequency increases.

Red Shift

When an object, such as a star, is travelling away from Earth, the wavelength of light observed increases while frequency decreases.

The greater the speed of the star/galaxy receding (from Earth)...

, the greater the red shift

Cosmic Microwave Background Radiation (CMBR)

Electromagnetic radiation (heat) that has been traveling through space ever since it was created shortly after the Big Bang.

Initial Big Bang heat should now be thinly spread across the whole Universe...

CMBR is everywhere at a temperature of about -270°C

Dark Energy

An unknown form of energy, put forward as a solution to the problem of why the expansion of the Universe is accelerating all the time.

Dark Matter

An unidentified form of matter that accounts for galaxies rotating faster than their visible mass should cause.

Big Crunch

If the density of the universe is more than a particular amount, it will stop expanding and go into reverse.

Big Yawn

If the density of the universe is less than a particular amount, it will expand forever. The stars will die out.