Image From: http://www.astronomy-pictures.net/spiral_galaxy.jpg;

AstronomyNotes

Part 1

Notes Created by Harris Middle School with graphics cited.

Size of the planets compared to the Sun

Scale model !Scale model !

The Inner Planets and our moon (The Terrestrial Planets)

Scale model !

The Outer Planets compared to the Inner Planets

(The Gas Giants)

Scale model !

Click: http://www.youtube.com/watch?v=HEheh1BH34Q

1. Universe- contains everything that may or may not exist in space2. Galaxy- system of stars held together by gravity. 3 types: Spiral, Elliptical, and Irregular. Ex: Milky Way3. Nebula= interstellar cloud of gas4. Star- self luminous sphere of gas. Ex: sun5. Planet- celestial object moving in orbit around star.6. Moon- ex: small object orbits a planet.

Stars• An object made of gas that gives off energy

– mainly hydrogen– helium

The Sun• medium in size & life span compared to other stars• primary energy source for all processes on Earth• much closer to Earth than any other star!• about 4 ½ billion years old

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Nebula

Black Dwarf

1. Large cloud of gas & dust where stars form.

3. ExpandsExplodes!

5. Collapses to just its

core

4. Outer layers come off

or

Iike our Sun!

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2. Gravity pulls material into a

sphere that becomes

dense, hot& ignites.

Hertzsprung-Russell DiagramHertzsprung-Russell Diagram• Chart to classify luminosity & temperature of stars• Luminosity- how BRIGHT or DIM star is. (y-axis)

• Temperature-  higher (hotter) temperatures on left, and lower (cooler) temperatures are on right. (x-axis)

Temperature and Color

H-R Diagram

H-R Diagram: Shows the relationship between color, temperature, magnitude & size of stars.

• Color = temperature• Luminosity = how bright• Our Sun is a main sequence star.

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H-R Diagram

H-R Diagram copy and label in journal as (HOT,COOL) (BRIGHT, DIM)

temperature

Lum

ino

sity

SUN

______, _______

______, _______

______, _______

______, _______

H-R Diagram ANSWERS copy and label in journal as (HOT,COOL) (BRIGHT, DIM)

temperature

Lum

ino

sity

SUN

BRIGHT HOT

______, _______

______, _______

______, _______

Galaxy• A large grouping of stars, dust/gas in space• 3 types

1. Spiral – bulge in center & distinctive spiral arms• Example: Our galaxy, The Milky Way• Our solar system is located within an arm

2. Elliptical – spherical or elongated3. Irregular

1 2 3

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Our Solar SystemTerrestrial Planet: a rocky, INNER planet

Mercury• closest to the sun• no atmosphere

• full of craters• very hot during day; freezing cold at night

Venus• Similar in size to Earth• Hot, thick & poisonous atmosphere

Earth – home!

Mars• known as the “red planet” because of its iron-

rich soil

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Gas Giant: large, OUTER planet that is made mostly of gases

Jupiter• largest planet• known for its storm, “The Great Red Spot”

Saturn• known for its ring system

Uranus• known for blue-green atmosphere

Neptune• blue-green atmosphere like Uranus• Also has a storm, “The Great Dark Spot”

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Other Rocky Bodies...Asteroids• asteroid belt between Mars & Jupiter• small, rocky body that revolves around the Sun

Meteoroids – in space (like asteroids), but usually smaller

Meteors – (meteor shower); a bright streak of light caused by the rock burning as it streaks through the atmosphere

Meteorites – piece of rock that has landed on Earth without completely burning up, possibly making a crater

Comet – a body of ice, rock and dust that forms a tail as it gets close to the Sun

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Light YearA measure of how long it takes light to travel through space in one year.

Image From: http://uniqhorns.com/images/milkyway.gif; Definition: www.thefreedictionary.com 9 of 11

Electromagnetic SpectrumThe range of all the waves that can travel through matter as well as empty space.

Image From: http://www.lcse.umn.edu/specs/labs/images/spectrum.gifDefinition: www.thefreedictionary.com

R O Y G B I V

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Scientists use different portions of the spectrum to learn about the universe.

Ex: light waves can tell us what elements stars are made & if they are moving away or towards other objects.

Theories on the Origin of the Universe1. Steady State – has always been the same

2. Oscillating Model - began by expanding, has slowed down & is now contracting

3. Big Bang - *the dominant theory• 12 to 15 billion years ago• Universe began as a dense point that exploded• It rapidly expanded & began to cool down,

forming stars, etc.• Evidence

discovery of cosmic background radiation red shift in EM spectrum suggest it is still expanding

11 of 11Click for Big Bang BrainPOP: http://www.brainpop.com/science/space/bigbang/