Science Unit 2 Part 4

Universe

All the space, time, matter, and energy. It includes everything from subatomic particles to palaxies, stars, planets, and all the fundamental forces that govern them.

The Big Bang Theory

• ~13.7 Billion years ago

• a dense ball of matter and gas expanded outward. (Singularity) George Lemaitre

The universe is still expanding

• We think this because mathematical formulas and models and by observing the ‘echo” of the expansion through a phenomenon known as the cosmic microwave background radiation

Hubble’s Law

• Made by Edwin Hubble

• Using evidence (spectroscope/poppler shift) he made a claim that “The universe is expanding”

Universal Expansion

-74.2 (± 3.6) km/sec/mpc.

Electromagnetic Energy

• E.M.E

• all energy that can travel through space (does not need a medium)

• all matter gives off Electromag Energy (E.M.E) ex. humans, desks

• energy is released in the form of transverse

Electromagnetic Spectrum

• The range of wavelengths spans from: radio waves to cosmic waves

Spectrum of Visible Light

• when visible light passes through a prism it produces a continuous spectrum of colors

continuous

rainbow

absorption

dark line

emission

bright lines

Solar Spectrum

• Joseph Von Fraunhofer

What does Hubble’s Law state?

• The universe is expanding

• The Doppler effect gives evidence to support this claim

Red Shift

• lower frequency

• longer wavelength

• objects that are moving away from us give off frequency waves

• waves spread out

Blue Shift

• high frequency

• short wavelength

• objects that are moving towards us give off high frequency waves

• waves bunch

The greater the red shift

The faster it was moving away

The greater the blue shift

the faster it was moving towards us

after the “Big Bang” matter began to cool & gravity caused it to condense/clump, which formed unorganized small groups of stars called

Protostars

Once fully organized they form:

galaxies

Galaxy

• hundreds of billions of stars, gas, and dust held together gravity

total mass causes various shapes and different sizes to form:

• spiral galaxies

• elliptical galaxies

• irregular galaxies

Milky Way

• contains about 200  billion stars

• rotates counter clockwise

• diameter is about 100,000 Ly

• Thickness is just 1,000 Ly

• The galactic disk is very thin compared with the galactic bulge

Hubble- Vaucouleur’s Sequence

• Elliptical

• Lenticular

• Spiral