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MMMMERCURY; ERCURY; ERCURY; ERCURY; VVVVENUS; ENUS; ENUS; ENUS; EEEEARTH; ARTH; ARTH; ARTH; MMMMARS; ARS; ARS; ARS; JJJJUPITER; UPITER; UPITER; UPITER; SSSSATURN; ATURN; ATURN; ATURN; UUUURANUS; RANUS; RANUS; RANUS; NNNNEPTUNE; EPTUNE; EPTUNE; EPTUNE;

PPPPLUTOLUTOLUTOLUTO

MMMMy y y y VVVVery ery ery ery EEEExcellent xcellent xcellent xcellent MMMMother other other other JJJJust ust ust ust SSSServed erved erved erved UUUUs s s s NNNNine ine ine ine PPPPizzasizzasizzasizzas

MERCURY

• Smallest and fastest planet

• Orbit is 88 days

• Surface is rocky and covered

with craters

• Has no moon

VENUS

*Smaller than the Earth

• *Wrapped in bright clouds (greenhouse effect)

• Hottest Planet ; Temperatures 4640 C to 4800 C

• Air is poisonous to humans; contains CO2

• High pressure

• No moon

• Composition: Mostly rock

(Terrestrial)

EARTH

•The Earth is 93 million miles away from the sun

(150 million km)

• The different layers of the Earth are: Crust, Mantle, Core

• Orbits the Sun in 365 days (= 1 year)

• Rotates in 24 hours (= 1 day)

• One moon

LUNA

THE EARTH’S MOON

• Dry, dusty land, flat

plains, and craters

• Earth’s gravity keeps

the moon from going in a straight line

• The light of the moon is the reflection of the sun’s

light

• The dark side of the moon is the Earth’s shadow

PHASES OF THE MOON

• We always see the same side of the moon

•• RevolutionRevolution (orbit around the earth) is 27.3 days = 1 month

• The positions of the moon, sun, and Earth determine the phases of

the moon

ECLIPSES

• A lunar eclipse happens

when Earth comes between

the sun and the moon and

the shadow of Earth falls on the moon

• A solar eclipse happens when the moon comes between Earth

and the sun and the shadow of the moon falls on part of Earth

MARS

• Rocky and shaped by running water

• Looks red because the soil is rich in

rust (iron oxide)

• Same rotation as Earth (day)

• Revolution is twice as long as Earth (687 earth days)

• Has two small moons

• Mons Olympus is a volcano, 16 miles high

JUPITER• A giant gas ball

• The planet of storms

• The Great Red Spot is a storm that

never changes and it is as big as 3 Earths

• Jupiter’s atmosphere consists of hydrogen, helium, some ammonia,

methane, and H2O

• Temperature of its interior can be 30,0000C

• High winds (540 km/h)

• Distance from sun 5,2 AU

• Rotation: 9h, 55 min

• Revolution: 11 years, 314 days

JUPITER’S MOONS

• Europa, Ganymede, Callisto, and Io are Jupiter’s largest moons

• Ganymede is the largest moon in the solar system

List of all Jupiter Moons (63):

1. Metis 2. Adrastea 3. Amalthea 4. Thebe 6. Europa 7. Ganymede

8. Callisto 9. Themisto 10. Leda 11. Himalia 12. Lysithea 13. Elara

14. S/2000 15. Carpo 16. S/2003 17. Euporie 18. S/2003 19. S/2003

20. Thelxinoe 21. Euanthe 22. Helike 23. Orthosie 24. 25. S/2003

26. Ananke 27. Praxidike 28. Harpalyke 29. Hermippe 30. Thyone

31. Mneme 32. S/2003 33. Aitne 34. Kale 35. Taygete 36. S/2003

37. Chaldene 38. S/2003 39. S/2003 40. S/2003 41. Erinome 42. Aoede 43. Kallichore 44. Kalyke 45. Eurydome 46. S/2003 47. Pasithee

48. Cyllene 49. Eukelade 50. S/2003 51. Hegemone 52. Arche

53. Carme 54. Isonoe 55. S/2003 56. S/2003 57. Pasiphae 58. Callirrhoe 59. Sinope 60. Sponde 61. Autonoe 62. Megaclite 63. S/2003

SATURN

• 800 times bigger than the Earth

• Many moons (more than 53)

• Titan is the largest moon of Saturn

• Has rings

SATURN’S MOONS

• MAJOR MOONS (53 + 9): Pan 1990; Atlas 1980; Prometheus 1980; Pandora 1980; Epimetheus 1980; Janus 1966; Mimas 1789; Enceladus 1789; Tethys 1684; Telesto 1980; Calypso 1980; Dione 1684; Helene1980; Rhea 1672; Titan 1655; Hyperion 1848; Iapetus 1671; Phoebe 1898

• RINGS: A-Ring, B, C, D, E, F, G.

URANUS

• 300 times bigger than the Earth

• 84 Earth years to orbit the sun

• Strange thing: Orbits the sun on its side

• Has rings

NEPTUNE

• 300 times larger than the Earth

• Two moons

• Jupiter, Saturn, Uranus, Neptune are called

OUTER PLANETS and GAS GIANTS

PLUTO

• Dwarf planet in Kueper Zone

• Rock and ice

• Charon is Pluto’s moon

• Charon is the COLDEST place on the entire solar system

ASTEROID BELT

• Between the INNER PLANETS and the

OUTER PLANETS is the Asteroid Belt

• Full of asteroids that orbit the SUN

• ASTEROIDS are made of chunks of rock and some ice and orbit

the sun

GALAXIES

• Galaxies are identified based on their shape

• Clusters of billions of stars with different shapes: spiral, elliptical, irregular

• Galaxies are composed of stars, star clusters, nebulas, and planetary systems

• Classified by shape and by rate of star formation

• Spiral galaxies have

a bulge at the center and

spiral arms.

The Milky Way

• Our galaxy is a spiral shape and is called the Milky Way

• Consists of about 200 billion stars

• The sun is located about 2/3 of the way between the center of the galaxy and the galaxy’s edge

ELLIPTICAL GALAXIES

• Elliptical Galaxies Elliptical Galaxies Elliptical Galaxies Elliptical Galaxies are round or oval (cosmic snowballs)

• They have stopped making new stars more than 10 billion years

ago.

• They are the largest galaxies largest galaxies largest galaxies largest galaxies in the universe

• Contain up to 5 trillion stars

• They form by the merging of smaller galaxies

IRREGULAR GALAXIESIRREGULAR GALAXIES

• Irregular galaxies Irregular galaxies Irregular galaxies Irregular galaxies are galaxies that have no definite shape

• SmallestSmallestSmallestSmallest ones have

only about 10 million stars

• Form new stars slowly

• Some form when galaxies collide

• The Milky Way Milky Way Milky Way Milky Way is consuming a pair

of nearby irregular galaxies

CONTENTS OF GALAXIES

• Galaxies contain stars, planetary systemsstars, planetary systemsstars, planetary systemsstars, planetary systems, gas clouds gas clouds gas clouds gas clouds and star star star star

clustersclustersclustersclusters

• Gas Clouds Gas Clouds Gas Clouds Gas Clouds are called nebulasnebulasnebulasnebulas and they are large clouds of gas

and dust where stars are born

• Some nebulas glowglowglowglow, other types absorb light absorb light absorb light absorb light and hide stars, and

others reflect starlightreflect starlightreflect starlightreflect starlight

STAR CLUSTERS

• A globular cluster globular cluster globular cluster globular cluster is a highly concentrated group of stars that

looks like a ball

• May have up to 1 million stars1 million stars1 million stars1 million stars

• Open clusters Open clusters Open clusters Open clusters are groups of 100 to 1,000 stars that are close

together relative to other stars

QUASARS

• Quasars are among the most distant objects in the universe

• Star like sources of energy that are located in the centers of galaxies

• They generate energy at a high rate and are among the most powerful energy sources in the universe

• May be caused by massive black holes in the cores of galaxies

• The quasar known as PKS 0637-752 radiates with the power of 10 trillion suns

ORIGIN OF GALAXIESORIGIN OF GALAXIES

• Scientists investigate the early universe early universe early universe early universe by observing objects that

are extremely far away in space

• Because light takes time to travel through space, looking through

a telescope is like looking back in time

• Looking at distant galaxies

reveals what early galaxies

looked like

FORMATION OF THE UNIVERSE

The Big Bang TheoryThe Big Bang Theory

• Most galaxies are moving away from each other and the universe is expanding

• About 14 billion years ago, all of the contents of the universe were compressed under tremendous pressure, at high temperature and high density, into an extremely small volume

• The universe was contracting and all matter squeezed together in one small volume

• Then expanded and cooled

• Galaxy formation

FORMATION OF THE SOLAR SYSTEM

• The collision of particles formed

bodies the size of boulders and

asteroids

• As the mass of particles

increased, gravity increased

• Matter in the solar nebula was

pulled together by gravity into

spheres

• The solar nebula collapsed, rotated

• Becomes hot and dense in its center

• The gas and dust forms a disk

• The disk begins to cool enough for dust

particles to form

• Particles begin to collide and form larger larger larger larger

particlesparticlesparticlesparticles

• Gravitational attraction Gravitational attraction Gravitational attraction Gravitational attraction pulls objects toward one another

• All objects experience gravityAll objects experience gravityAll objects experience gravityAll objects experience gravity

• After the big bang, gravitational attraction gravitational attraction gravitational attraction gravitational attraction caused the matter

distributed throughout the universe to form galaxiesgalaxiesgalaxiesgalaxies

• The mutual attraction mutual attraction mutual attraction mutual attraction between galaxies caused galaxies to cluster

• Even though the distances between galaxy clusters are very large,

gravity still acts between themgravity still acts between themgravity still acts between themgravity still acts between them

• Because gravity acts over such great distances, gravity controls gravity controls gravity controls gravity controls

the size and shapethe size and shapethe size and shapethe size and shape of the universe

HOW OLD IS THE UNIVERSE?

• Astronomers can estimate the age of the universe by studying white dwarfs, the oldest stars in the Milky Way

• White dwarfs are the burned-out cores of stars that started out with masses that were less than 8 times the mass of the sun

• These stars have cores of carbon and oxygen at the end of the red giant phase

• They lose their atmospheres in the planetary nebula stage

• The planetary nebula stage is a stage in which the hot central region of a star drives off the star’s cooler atmosphere over a period of a few thousand years.

HOW OLD IS THE UNIVERSE?

• Once the star’s atmosphere is lost, all that is left is the carbon-oxygen core- a white dwarf-which is tiny, hot, and dense

• The oldest white dwarfs are 12 billion to 13 billion years old

• Because it took about 1 billion years after the big bang for the first white

• dwarfs to form from the first

stars, the universe must be

approximately 14 billion years old

THE LIFE CYCLE OF STARSTHE LIFE CYCLE OF STARS

• Stars can exist for billions of years

• Scientists study stars at different stages to

understand how they develop

• Stars are classified by mass, size,

brightness, color, temperature,

composition, and age

• Stars are different as they age

• The fast-expanding gas clouds

in the picture show a dying star

LIFE CYCLE OF SUNLIKE STARSLIFE CYCLE OF SUNLIKE STARS

PROTOSTARSPROTOSTARS --1st Stage

• A star begins its life as a ball of gas and dust

• Gravity pulls the gas and dust into a sphere

• As the sphere becomes denser it gets hotter and

hotter to 10,000,000 in its center

• Hydrogen nuclei combine to become helium

• This is called nuclear fusion

• Causes energy to be released

LIFE CYCLE OF SUNLIKE STARSLIFE CYCLE OF SUNLIKE STARSLIFE CYCLE OF SUNLIKE STARSLIFE CYCLE OF SUNLIKE STARS

MAINMAIN--SEQUENCE STARS SEQUENCE STARS

• After it is formed, it enters the main sequence

• Second and longest stage of its life cycle

• Energy is generated in the core of the star as hydrogen atoms fuse

into helium atoms.

• SizeSizeSizeSize changes very little

LIFE CYCLE OF SUNLIKE STARSLIFE CYCLE OF SUNLIKE STARSLIFE CYCLE OF SUNLIKE STARSLIFE CYCLE OF SUNLIKE STARS

GIANTS AND SUPERGIANTSGIANTS AND SUPERGIANTS

• When a mainmainmainmain----sequencesequencesequencesequence star uses all of the hydrogenhydrogenhydrogenhydrogen in its corecorecorecore,

heliumheliumheliumhelium begins to fuse

• The centercentercentercenter of the star shrinksshrinksshrinksshrinks

• The atmosphereatmosphereatmosphereatmosphere of the star grows very large very large very large very large and coolscools

• The star may become a red giant red giant or

red supergiantsupergiant ex. Betelgeuseex. Betelgeuseex. Betelgeuseex. Betelgeuse

LIFE CYCLE OF SUNLIKE STARSLIFE CYCLE OF SUNLIKE STARSLIFE CYCLE OF SUNLIKE STARSLIFE CYCLE OF SUNLIKE STARS

WHITE DWARFSWHITE DWARFS

• In the final stage of its life cycle, a sunlike star becomes a white white white white

dwarfdwarfdwarfdwarf

• Small, hot, Small, hot, Small, hot, Small, hot, and dim star dim star dim star dim star that is the leftover center of a red giant

• No longer No longer No longer No longer generates energy by nuclear fusion

• Slowly cools and becomes smaller

• A white dwarf white dwarf white dwarf white dwarf can shine for billions of years

H-R DIAGRAM

The Sun

*Middle age

*5 billion years old

BlueBlue = Hot

YellowYellow = MediumRedRed = Cool

THE AGING OF MASSIVE STARS

• Massive stars Massive stars Massive stars Massive stars use their hydrogen much faster than stars like the sun

do

• More energy and they are very hot!

• Shorter lives

SUPERNOVASSUPERNOVASSUPERNOVASSUPERNOVAS

• At the end, a massive star may explode in a large, bright flash called

supernova

• A supernova is a gigantic explosion gigantic explosion gigantic explosion gigantic explosion in which a massive star collapsescollapsescollapsescollapses

and its outer layers are blasted into space

THE AGING OF MASSIVE STARS

PULSARS -If a neutron star is spinningspinningspinningspinning, it is

called a pulsarpulsarpulsarpulsar

• PulsarsPulsarsPulsarsPulsars send out beams of

radiationradiationradiationradiation that sweep across

space like a lighthouse over

the ocean

• Detected by radio telescopes

as pulses

THE AGING OF MASSIVE STARS

NEUTRON STARS

• The centercentercentercenter of the supernovasupernovasupernovasupernova (collapsed star) may contract into a

very small very small very small very small but very dense very dense very dense very dense ball of neutronsneutronsneutronsneutrons

• This ball of neutrons is called Neutron StarNeutron StarNeutron StarNeutron Star

• One teaspoon of matter from a neutron star would weigh 100

million metric tons of Earth

• A lot of energyenergyenergyenergy (100,000 suns)

THE AGING OF MASSIVE STARS

BLACK HOLES

• An object so dense and massive that light cannot escape its gravity

• If the center of a collapsed star has a mass several times the mass

of the sun, the star may contract more because of too much gravity

• The force of the contraction crushes the dense center of the star

and leaves a black holeblack holeblack holeblack hole

BLACK HOLES

BLACK HOLES

BLACK HOLES

• Black holes Black holes Black holes Black holes do not give off light

• Locating them is difficult

• If a star is nearby, some gas some gas some gas some gas or dustdustdustdust from the star will spiral into the

black hole and give off X raysX raysX raysX rays

• These X rays allow astronomersastronomersastronomersastronomers to detect the presence of black holes

• The sun will never will never will never will never become a Black Hole

• Stars with 10 10 10 10 ----100 million times 100 million times 100 million times 100 million times the massmassmassmass of the sun

• StellarStellarStellarStellar---- Mass Black Hole Mass Black Hole Mass Black Hole Mass Black Hole & Supermassive Black HoleSupermassive Black HoleSupermassive Black HoleSupermassive Black Hole

INTERPLANETARY DISTANCES

• Astronomical Unit Astronomical Unit Astronomical Unit Astronomical Unit (AU) is the average distance between the sun and

Earth (150,000,000 km)

• Light minute or light hour

• 1s = 300,000 km

• 1 min = 18,000,000 km (light minute)

• 1 AU = 8.3 light minutes

• Used to measure distances within the SOLAR SYSTEM

Example: between planets or the sun and a planet

• Light YearLight YearLight YearLight Year: used to measure outside the solar system =9.5 trillion km

Example: between galaxies and stars

CometsCometsCometsComets

• Small, loosely packed bodies of ice, rockice, rockice, rockice, rock, and cosmic dustcosmic dustcosmic dustcosmic dust

• The coreThe coreThe coreThe core is rock, metals, and water ice

• The comaThe comaThe comaThe coma surrounds the nucleus and is made of gasgasgasgas and dustdustdustdust

• Comet tailsComet tailsComet tailsComet tails————sunlight sunlight sunlight sunlight causes the comet’s ice to change to gas thus

forming the tails

• One tail is made of ionized gas ionized gas ionized gas ionized gas (no electrons) and points away from

the sun

• The other is made of dustdustdustdust and gasgasgasgas

CometsCometsCometsCometsCometsCometsCometsComets

• CometsCometsCometsComets are found in the KuiperKuiperKuiperKuiper belt (flat ring of objects located

beyond Neptune’s orbit)

• Oort cloudOort cloudOort cloudOort cloud--spherical cloud of dust and ice that surrounds the solar

system far beyond Pluto’s orbit

ASTEROIDS--Asteroid BeltAsteroid BeltAsteroid BeltAsteroid Belt

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• Asteroid Belt is made of asteroids between

Mars and Jupiter

• Located between the Inner Solar System and

the Outer Solar System

• Asteroids are small (1,000 km)

rocky and some metal bodies

• Revolve around the sun

MeteoroidsMeteoroidsMeteoroidsMeteoroids

• DustDustDustDust and debrisdebrisdebrisdebris from

asteroids and comets within

our solar system

• When enter Earth’s atmosphere

reach speeds of 35,000-250,000 km/h

• Friction heats Friction heats Friction heats Friction heats the meteoroids to

thousands of degrees Celsius

• GlowGlowGlowGlow brightly

MeteorsMeteorsMeteorsMeteors

• The glowing trails glowing trails glowing trails glowing trails that result when meteoroidsmeteoroidsmeteoroidsmeteoroids burn up in

Earth’s atmosphere

MeteoritesMeteoritesMeteoritesMeteorites

• Larger bodies that pass through Earth’s atmosphere without burning up

and strike Earthstrike Earthstrike Earthstrike Earth

• Three types: Stony, metallic, Stony-iron meteorites

METEOR SHOWERS

• Meteors can be seen on almost

any night away from lights

• When a large number of small

• meteoroids enter Earth’s atmosphere in a short period of time a

meteor shower occurs

• Occurs when Earth intersects the orbits of comets that have left

behind a trail of dust

METEOR SHOWERS

POINTS TO REMEMBER

• The solar system formed as a result of

gravitational attraction in the solar nebula

• Gravity and pressure were major factors in the

formation of the solar system

• The sun is a star that produces energy by

nuclear fusion

• Astronomers use the astronomical unit to

measure distances in the solar system

POINTS TO REMEMBER

• The four planets of the inner solar systeminner solar systeminner solar systeminner solar system are small, dense, and small, dense, and small, dense, and small, dense, and

rocky rocky rocky rocky and are close to the sunclose to the sunclose to the sunclose to the sun

• The inner planets, or terrestrial planets, are: Mercury, Venus,

Earth, and Mars

• The planets of the outer solar system have deep, massive gas atmospheres

• Jupiter, Saturn, Uranus, and Neptune are the outer planets or the gas giants

• Pluto is made of rock and ice and is a dwarfplanet

POINTS TO REMEMBER

• Moons are bodies that are smaller than planets and that orbit orbit orbit orbit

planetsplanetsplanetsplanets

• Earth’s moon formed when an object collided with Earth

• The moon’s appearance changes as the moon revolvesrevolvesrevolvesrevolves around

earth

• Moons Moons Moons Moons of other planets vary greatly in size and composition

POINTS TO REMEMBER

• CometsCometsCometsComets, asteroidsasteroidsasteroidsasteroids, and meteoroidsmeteoroidsmeteoroidsmeteoroids are small bodies in our solar

system that orbit the sun

• CometsCometsCometsComets are small bodies of iceiceiceice and rockrockrockrock that have very elliptical elliptical elliptical elliptical

orbitsorbitsorbitsorbits

• Most asteroidsasteroidsasteroidsasteroids are located in a beltbeltbeltbelt between Mars and JupiterMars and JupiterMars and JupiterMars and Jupiter

• MeteoroidsMeteoroidsMeteoroidsMeteoroids are dustdustdustdust and debrisdebrisdebrisdebris from asteroidsasteroidsasteroidsasteroids and cometscometscometscomets