AstronomyAstronomy

The Solar SystemThe Solar System

Our Our solar systemsolar system consists of one Sun, consists of one Sun, eight planets, a few dwarf planets, and eight planets, a few dwarf planets, and many, many, moons.many, many, moons.

The solar system also contains asteroids, The solar system also contains asteroids, meteors, meteorites, meteoroids and meteors, meteorites, meteoroids and comets to name a few.comets to name a few.

The solar system also has man made The solar system also has man made items, also. Such as, satellites, rockets, a items, also. Such as, satellites, rockets, a space station, and “space junk.”space station, and “space junk.”

THE SUNTHE SUN The Sun is the closest The Sun is the closest starstar to us to us It is what gives us light and energy for lifeIt is what gives us light and energy for life It is 92 million miles away from Earth = one It is 92 million miles away from Earth = one

astronomical unit (AU)astronomical unit (AU) It is like a giant nuclear power plant, constantly It is like a giant nuclear power plant, constantly

converting Hydrogen into Helium. (H -> He)converting Hydrogen into Helium. (H -> He) It will eventually die out once it loses its fuel It will eventually die out once it loses its fuel

source, and the star will collapse source, and the star will collapse

The The SSuunn’’ss InteriorInterior

The CoreThe Core: the location in the center of the star : the location in the center of the star where the nuclear fusion is taking placewhere the nuclear fusion is taking place

The Radiation ZoneThe Radiation Zone: middle layer where the : middle layer where the energy very slowly passes from the core energy very slowly passes from the core outwardoutward

The Convection ZoneThe Convection Zone: outermost layer where : outermost layer where the hot gases rises from the RZ and cool and the hot gases rises from the RZ and cool and then fall back towards the RZ—creating a then fall back towards the RZ—creating a convection currentconvection current

The Sun’s InteriorThe Sun’s Interior

Features on the SunFeatures on the Sun

SunspotsSunspots: cool areas located on the Sun: cool areas located on the SunProminencesProminences: loops of gas usually linking : loops of gas usually linking

groups of sunspotsgroups of sunspotsSolar FlareSolar Flare: connected prominences that : connected prominences that

have so much energy that they are have so much energy that they are released from the Sun out into spacereleased from the Sun out into spaceThey can be seen as auroras on EarthThey can be seen as auroras on EarthThey can disrupt our satellite links and cell They can disrupt our satellite links and cell

phone servicesphone services

Prominence

Prominence and Solar Flares

Sunspot

AurorasAuroras

Sun SpotsSun Spots

Solar flare: March 9, 2012Solar flare: March 9, 2012http://abclocal.go.com/wpvi/video?id=8575

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StarsStars

Stars are classified according to their color, temperature, Stars are classified according to their color, temperature, size, composition, and brightness.size, composition, and brightness.

Color: determined by the temperatureColor: determined by the temperature (coolest) (coolest) RedRed Red-OrangeRed-Orange YellowYellow White White BlueBlue (hottest) (hottest) 00C 3000 4500 5750 10,000 50,000C 3000 4500 5750 10,000 50,000

Size: Even though they all appear the same to us, they can Size: Even though they all appear the same to us, they can be very differentbe very different

Composition: Helium, Hydrogen, Sodium, CalciumComposition: Helium, Hydrogen, Sodium, Calcium Brightness: depends on its size and temperatureBrightness: depends on its size and temperature

Apparent Brightness: Brightness as seen from EarthApparent Brightness: Brightness as seen from Earth Absolute Brightness: Brightness of the star if we were all at equal Absolute Brightness: Brightness of the star if we were all at equal

distances to every stardistances to every star

The Hertzsprung-Russell DiagramThe Hertzsprung-Russell Diagram

The EIGHT PlanetsThe EIGHT Planets(plus Pluto)(plus Pluto)

The Inner PlanetsThe Inner Planets Small and RockySmall and Rocky Few or no MoonsFew or no Moons

MercuryMercuryVenusVenusEarthEarthMarsMars

The Outer PlanetsThe Outer Planets Large and gaseousLarge and gaseous Many MoonsMany Moons All have ringsAll have rings

JupiterJupiterSaturnSaturnUranusUranusNeptuneNeptune

Planets’ orbits around the SunPlanets’ orbits around the Sun

Poor PlutoPoor Pluto Why doesn’t Pluto qualify as a planet?Why doesn’t Pluto qualify as a planet?

It’s too smallIt’s too small It doesn’t fit the pattern of a planet in that location in our It doesn’t fit the pattern of a planet in that location in our

solar systemsolar system Its orbit is out of sync with the other planetsIts orbit is out of sync with the other planets

It is now considered a It is now considered a DWARF PLANET DWARF PLANET Sometimes called a sub-planetSometimes called a sub-planet

Mercury — Inner PlanetMercury — Inner Planet

Smallest PlanetSmallest PlanetClosest to the SunClosest to the SunHas virtually no atmosphere, which is why Has virtually no atmosphere, which is why

it has so many cratersit has so many cratersMoon: noneMoon: noneDay: 59 Earth daysDay: 59 Earth daysYear: 0.24 Earth Year Year: 0.24 Earth Year

( about 88 days) ( about 88 days)

Venus — Inner PlanetVenus — Inner Planet

Very similar is size and shape to Earth, so Very similar is size and shape to Earth, so it is sometimes called “Earth’s Twin”it is sometimes called “Earth’s Twin”

Its atmosphere is so thick its always Its atmosphere is so thick its always cloudy, but those clouds are acidic!cloudy, but those clouds are acidic!

Moon: noneMoon: noneDay: 243 Earth daysDay: 243 Earth daysYear: 0.62 Earth YearsYear: 0.62 Earth Years

( 226 days)( 226 days)

Earth — Inner PlanetEarth — Inner Planet

Rocky planet with an atmosphere which is Rocky planet with an atmosphere which is mostly Nitrogenmostly Nitrogen

Only planet with LifeOnly planet with LifeOnly planet with Only planet with

liquid water liquid waterMoon: oneMoon: one

Mars — Inner PlanetMars — Inner Planet The RED PLANETThe RED PLANET The atmosphere is 95% COThe atmosphere is 95% CO22.. The planet has extreme temperature The planet has extreme temperature

differences…70differences…70ooF during the day and F during the day and -225-225ooF at night! F at night!

Mars also is tilted like Earth, so it too Mars also is tilted like Earth, so it too has seasonshas seasons

Location we are planning on making a Location we are planning on making a space station in the near futurespace station in the near future

Moons: twoMoons: two Day: 24.7 Earth hoursDay: 24.7 Earth hours Year: 1.9 Earth YearsYear: 1.9 Earth Years

(693 Earth Days)(693 Earth Days)

Asteroid BeltAsteroid Belt The inner planets and the outer planets are The inner planets and the outer planets are

separated by an asteroid beltseparated by an asteroid belt An asteroid is a small rocky substance that An asteroid is a small rocky substance that

orbits the Sunorbits the Sun

Jupiter – Outer PlanetJupiter – Outer Planet

Largest PlanetLargest Planet Thick atmosphere made out Thick atmosphere made out

of Hydrogen and Heliumof Hydrogen and Helium Probably has a dense core, Probably has a dense core,

but most of the planet is but most of the planet is gaseousgaseous

Has ringsHas rings Moons: 60+ Moons: 60+ Day: 10 Earth HoursDay: 10 Earth Hours Year: 12 Earth YearsYear: 12 Earth Years

Saturn—Outer PlanetSaturn—Outer Planet

Second largest planet in Second largest planet in the solar systemthe solar system

Well known for its system Well known for its system of ringsof rings

Gaseous planet made out Gaseous planet made out of Helium and Hydrogenof Helium and Hydrogen

Moons: 31+Moons: 31+ Day: 11 hoursDay: 11 hours Year: 29 yearsYear: 29 years

Uranus—Outer PlanetUranus—Outer Planet

Also a gaseous planet, with traces of methane Also a gaseous planet, with traces of methane which makes it blue-greenwhich makes it blue-green

It axis of rotation is tilted so it rotates head over It axis of rotation is tilted so it rotates head over heel instead of spinning like a topheel instead of spinning like a top

Does have ringsDoes have rings Moons:13+Moons:13+ Day: 16 hoursDay: 16 hours Year: 84 Earth YearsYear: 84 Earth Years

Neptune –Outer PlanetNeptune –Outer Planet

Cold, blue planetCold, blue planet It has clouds and storms, It has clouds and storms,

but not with water like but not with water like oursours

Does have ringsDoes have ringsMoons: 13+Moons: 13+Day: 16 hoursDay: 16 hoursYear: 164 yearsYear: 164 years

Meteors/Meteorites/MeteroidsMeteors/Meteorites/Meteroids

MeteoroidMeteoroid: free floating rock in outer space: free floating rock in outer spaceMeteorMeteor: rock fragments burning as they : rock fragments burning as they

make there way through our atmosphere; make there way through our atmosphere; we see them as “we see them as “Shooting StarsShooting Stars””

MeteoriteMeteorite: If there are any pieces of rock : If there are any pieces of rock that make it to the ground, the remaining that make it to the ground, the remaining piece is called a meteoritepiece is called a meteorite

Meteor or shooting star

Meteorites on Mars

Crater caused by meteorite

Black HolesBlack Holes

An object in space whose gravity is so An object in space whose gravity is so strong that not even light can escapestrong that not even light can escape

CometComet

CometsComets

Hale-Bopp 1997

Halley’s Comet

SeasonsSeasons

The seasons on Earth are due to the tilt of The seasons on Earth are due to the tilt of the Earth, the Earth, NOTNOT how close we are to the how close we are to the Sun.Sun.

We are actually closest to the Sun in the We are actually closest to the Sun in the Winter, but the Northern Hemisphere is Winter, but the Northern Hemisphere is tilted away from the sun, so we receive tilted away from the sun, so we receive less direct Sun rays.less direct Sun rays.

Tilt of the Earth causes SeasonsTilt of the Earth causes Seasons

During the winter, we are tilted AWAY from the Sun.During the summer, we are tilted TOWARDS the Sun

Distance of Earth to the Sun during Distance of Earth to the Sun during its Orbitits Orbit

We are CLOSER to the Sun on January 2nd than on July 2nd

Size ComparisonsSize Comparisons

Size ComparisonsSize Comparisons

Size ComparisonsSize Comparisons

Size comparisonsSize comparisons

History of the Earth in 2 minutesHistory of the Earth in 2 minutes

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