Universe

Mr. SkirbstPhysical Science

Topic 24

Watch Videos:VIDEO: The UniverseCLIP: Understanding the UniverseCLIP: Early Theories about the UniverseCLIP: Matter & Energy

UniverseBig Bang Theory

- the belief that the universe began with an explosion from a single point containing all the matter of the present universe

UniverseBig Bang Theory

- states that the universe is currently expanding in all directions

UniverseDoppler Effect

- apparent change in wavelength due to the movement of an object

http://astro.unl.edu/classaction/animations/light/dopplershift.html

Doppler EffectRed Shift

- spectrum shifted to red- indicates movement AWAY from an observer

Doppler EffectBlue Shift

- spectrum shifted to blue- indicates movement TOWARD an observer

http://upload.wikimedia.org/wikipedia/commons/1/14/Redshift.png

Features of the UniverseConstellations

- groups of stars that appear to form patterns in the sky

Features of the UniverseGalaxies

- major feature of the universe- huge collection of billions of stars

3 Types of Galaxies1. Spiral

- shaped like a pinwheel

You are here!

3 Types of Galaxies2. Elliptical

- varies from spherical to disk-like

3 Types of Galaxies3. Irregular

- no definite shape

Gravity- Force holding galaxies together- Matter “clumped” together by

gravity

Calculating Gravity

G = 4 pi2 L / T2

pi = 3.14L = .5mT = 1.4 sec

where: