AboveAboveandand

BeyondBeyond

Hubble TelescopeHubble Telescope

NASA named the world's NASA named the world's first space-based optical first space-based optical telescope after American telescope after American astronomer Edwin P. astronomer Edwin P. Hubble (1889–1953).Hubble (1889–1953).

Launch Date: Launch Date: April 24, 1990 from space shuttle April 24, 1990 from space shuttle

Discovery Discovery

Mission Duration:Mission Duration: Up to 20 yearsUp to 20 years $1.5 billion cost of launch$1.5 billion cost of launch

Length:Length: 43.5 ft (13.2 m) 43.5 ft (13.2 m)

Weight:Weight: 24,500 lb (11,110 kg) 24,500 lb (11,110 kg)

Maximum Diameter:Maximum Diameter: 14 ft (4.2 m) 14 ft (4.2 m)

Hubble is nearly the size of a large Hubble is nearly the size of a large school bus—but it can fit inside a school bus—but it can fit inside a space shuttle cargo bay.space shuttle cargo bay.

Can Hubble take pictures of Can Hubble take pictures of Earth?Earth?

The surface of the Earth is whizzing by as The surface of the Earth is whizzing by as Hubble orbits, and the pointing system, Hubble orbits, and the pointing system, designed to track the distant stars, designed to track the distant stars, cannot track an object on the Earth. cannot track an object on the Earth.

The shortest exposure time on any of the The shortest exposure time on any of the Hubble instruments is 0.1 seconds, and Hubble instruments is 0.1 seconds, and in this time Hubble moves about 700 in this time Hubble moves about 700 meters. So a picture Hubble took of meters. So a picture Hubble took of Earth would be all streaks.Earth would be all streaks.

The Hubble Space Telescope The Hubble Space Telescope whirls around Earth at a speed of whirls around Earth at a speed of five miles per second. If cars five miles per second. If cars moved that fast, a coast-to-coast moved that fast, a coast-to-coast trip across the continental U.S. trip across the continental U.S. would take only 10 minutes.would take only 10 minutes.

Time to Complete One Orbit:Time to Complete One Orbit: 97 97 minutes minutes

Speed:Speed: 17,500 mph (28,000 kph) 17,500 mph (28,000 kph)

Each day, the Hubble Each day, the Hubble Space Telescope collects Space Telescope collects enough data to fill an enough data to fill an _______________..

Hubble Can’t Observe:Hubble Can’t Observe: The Sun or Mercury, which is too close to The Sun or Mercury, which is too close to

the Sunthe Sun Hubble transmits about 120 gigabytes Hubble transmits about 120 gigabytes

of science data every week. of science data every week. That's equal to about 3,600 feet (1,097 That's equal to about 3,600 feet (1,097

meters) of books on a shelf. meters) of books on a shelf. The rapidly growing collection of pictures The rapidly growing collection of pictures

and data is stored on magneto-optical and data is stored on magneto-optical disks.disks.

Information/pictures are taken and held Information/pictures are taken and held for 1 year before being released to the for 1 year before being released to the public.public.

In an average orbit, Hubble In an average orbit, Hubble uses about the same amount uses about the same amount of energy as 28 - 100-watt of energy as 28 - 100-watt light bulbs.light bulbs.

Energy source:Energy source: _______________

In order to take images of distant, faint In order to take images of distant, faint objects, Hubble must be extremely objects, Hubble must be extremely steady and accurate. steady and accurate.

The telescope is able to lock onto a The telescope is able to lock onto a target without deviating more than target without deviating more than 7/1000th of an arcsecond (7/1000th of an arcsecond (Another Another measurement of angular separation, - one measurement of angular separation, - one sixtieth of an arc minute. (1/3600th of a sixtieth of an arc minute. (1/3600th of a degree.) degree.) , or about the width of a human , or about the width of a human hair seen at a distance of 1 mile.hair seen at a distance of 1 mile.

Pointing the Hubble Space Pointing the Hubble Space Telescope and locking onto Telescope and locking onto distant celestial targets is distant celestial targets is like holding a laser light like holding a laser light steady on a dime that is 200 steady on a dime that is 200 miles away.miles away.

MirrorsMirrors

Hubble's two mirrors were Hubble's two mirrors were ground so that they do not deviate ground so that they do not deviate from a perfect curve by more than from a perfect curve by more than 1/800,000ths of an inch. 1/800,000ths of an inch.

If Hubble’s primary mirror were If Hubble’s primary mirror were scaled up to the diameter of the scaled up to the diameter of the Earth, the biggest bump would be Earth, the biggest bump would be only six inches tall.only six inches tall.

Pictures from the Hubble Pictures from the Hubble TelescopeTelescope

VenusVenus

MarsMars

Jupiter – comet impacts on the planetJupiter – comet impacts on the planet

Jupiter triple eclipseJupiter triple eclipse

SaturnSaturn

Uranus – natural colorsUranus – natural colors

NeptuneNeptune

PlutoPluto

Pluto and Charon double photoPluto and Charon double photo

Barred Spiral GalaxyBarred Spiral Galaxy

Sombrero GalaxySombrero Galaxy

NebulaNebula

A term used to describe A term used to describe celestial objects which celestial objects which have a fuzzy, or nebulous, have a fuzzy, or nebulous, appearance (from the appearance (from the Latin for cloud.), such as Latin for cloud.), such as gas, or dust, clouds.gas, or dust, clouds.

Orion Orion NebulaNebula

4.1 billion 4.1 billion miles miles acrossacross

Located Located 1,500 light 1,500 light years awayyears away

Eagle Nebula M16Eagle Nebula M16 This is part of the This is part of the

"Eagle Nebula" (also "Eagle Nebula" (also called M16 -- the called M16 -- the 16th object in 16th object in Charles Messier's Charles Messier's 18th century catalog 18th century catalog of "fuzzy" objects of "fuzzy" objects that aren't comets), a that aren't comets), a nearby star-forming nearby star-forming region 7,000 light-region 7,000 light-years away in the years away in the constellation constellation Serpens. Serpens.

HorseheHorsehead ad

NebulaNebula

NovaNova

An existing An existing ____________________________ which suddenly which suddenly increases its brightness by more than 10 increases its brightness by more than 10 magnitudes and then slowly fades. magnitudes and then slowly fades.

SupernovaSupernova An An ____________________________. . Last one in our galaxy was about 400 Last one in our galaxy was about 400

years ago.years ago.

Mauna Kea, HawaiiMauna Kea, Hawaii

The summit of Mauna Kea on the Island of The summit of Mauna Kea on the Island of Hawaii hosts the world's largest Hawaii hosts the world's largest astronomical observatory, with telescopes astronomical observatory, with telescopes operated by astronomers from eleven operated by astronomers from eleven countries. countries.

The combined light-gathering power of the The combined light-gathering power of the telescopes on Mauna Kea is fifteen times telescopes on Mauna Kea is fifteen times greater than that of the Palomar telescope greater than that of the Palomar telescope in California -- for many years the world's in California -- for many years the world's largest -- and sixty times greater than that largest -- and sixty times greater than that of the Hubble Space Telescope. of the Hubble Space Telescope.

There are currently There are currently thirteenthirteen working working telescopes near the summit of telescopes near the summit of Mauna Kea. Mauna Kea.

Nine of them are for optical and Nine of them are for optical and infrared astronomy, three of them infrared astronomy, three of them are for submillimeter wavelength are for submillimeter wavelength astronomy and one is for radio astronomy and one is for radio astronomy. astronomy.

Mauna Kea ("White Mountain") is a Mauna Kea ("White Mountain") is a dormant volcano on the island of dormant volcano on the island of Hawaii, the largest and southernmost Hawaii, the largest and southernmost of the Hawaiian Islands. of the Hawaiian Islands.

Mauna Kea rises 9,750 meters (32,000 Mauna Kea rises 9,750 meters (32,000 ft) from the ocean floor to an altitude ft) from the ocean floor to an altitude of 4,205 meters (13,796 ft) above sea of 4,205 meters (13,796 ft) above sea level, which places its summit above level, which places its summit above 40 percent of the Earth's atmosphere. 40 percent of the Earth's atmosphere.

The atmosphere above the mountain The atmosphere above the mountain is extremely dry -- which is important is extremely dry -- which is important in measuring infrared and in measuring infrared and submillimeter radiation from celestial submillimeter radiation from celestial sources - and cloud-free, so that the sources - and cloud-free, so that the proportion of clear nights is among proportion of clear nights is among the highest in the world. the highest in the world.

The exceptional stability of the The exceptional stability of the atmosphere above Mauna Kea permits atmosphere above Mauna Kea permits more detailed studies than are possible more detailed studies than are possible elsewhere, while its distance from city elsewhere, while its distance from city lights and a strong island-wide lighting lights and a strong island-wide lighting ordinance ensure an extremely dark ordinance ensure an extremely dark sky, allowing observation of the sky, allowing observation of the faintest galaxies that lie at the very faintest galaxies that lie at the very edge of the observable Universe.edge of the observable Universe.

Keck TelescopesKeck Telescopes Keck 1 - Keck 1 -

leftleft Keck 2 - Keck 2 -

rightright

Keck Keck TelescopesTelescopes

Canada – Canada – France – Hawaii France – Hawaii TelescopeTelescope

Star trails Star trails above the above the Canada-Canada-France-Hawaii France-Hawaii Telescope. The Telescope. The shortest bright shortest bright trail belonds trail belonds to Polaris - the to Polaris - the pole star. pole star.

UH 2.2 UH 2.2 meter meter telescopetelescope

Optical/IR Optical/IR telescope telescope used mainly used mainly by UH faculty by UH faculty and studentsand students

The 1991 total The 1991 total solar eclipse solar eclipse seen from seen from Mauna Kea. Mauna Kea.

The totally eclipsed sun seen from The totally eclipsed sun seen from Mauna Kea in 1991. Mauna Kea in 1991.

The totally eclipsed sun seen from The totally eclipsed sun seen from Mauna Kea in 1991. Mauna Kea in 1991.

Diamond-ring at end of 1991 total solar Diamond-ring at end of 1991 total solar eclipse. eclipse.

Solar SystemSolar System

  The solar system consists of the The solar system consists of the SunSun; ; the nine planetsthe nine planets, more than 130 , more than 130 satellitessatellites of the planets, a large of the planets, a large number of small bodies (the number of small bodies (the cometscomets and and asteroidsasteroids), and the ), and the interplanetary medium. interplanetary medium.

Solar SystemSolar System

The The _______________solar system contains solar system contains the Sun, the Sun, MercuryMercury, , VenusVenus, , EarthEarth and and MarsMars: :

Solar SystemSolar System

      The planets of the The planets of the _______________solar solar system are system are JupiterJupiter, , SaturnSaturn, , UranusUranus, , NeptuneNeptune and and PlutoPluto: :

The Milky Way GalaxyThe Milky Way Galaxy This image of our galaxy, the Milky Way,

was taken with NASA's Cosmic Background Explorer's (COBE) Diffuse Infrared Background Experiment (DIRBE).

This never-before-seen view shows the Milky Way from an edge-on perspective with the galactic north pole at the top, the south pole at the bottom and the galactic center at the center.

Stars within our galaxy are the dominant source of light.

The whole solar system, together with the local stars visible on a clear night, orbits the center of our home galaxy, a spiral disk of 200 billion stars we call the _______________.

The nearest large galaxy is the _______________. It is a _______________like the Milky Way

but is 4 times as massive and is 2 million light years away.

OrbitsOrbits

  The The orbitsorbits of the planets are of the planets are _______________ with the Sun at one with the Sun at one focus, though all except Mercury focus, though all except Mercury and Pluto are very nearly circular. and Pluto are very nearly circular.

The orbits of the planets are all more The orbits of the planets are all more or less in the same or less in the same _______________ (called the (called the eclipticecliptic and defined by and defined by the plane of the Earth's orbit). the plane of the Earth's orbit).

Relative SizeRelative Size

One way to help visualize the relative sizes in the One way to help visualize the relative sizes in the solar system is to imagine a model in which it is solar system is to imagine a model in which it is reduced in size by a factor of a billion (reduced in size by a factor of a billion (1e91e9). ).

Then the Earth is about 1.3 cm in diameter (the Then the Earth is about 1.3 cm in diameter (the size of a grape). size of a grape).

The Moon orbits about a foot away. The Moon orbits about a foot away. The Sun is 1.5 meters in diameter (about the The Sun is 1.5 meters in diameter (about the

height of a man) and 150 meters (about a city height of a man) and 150 meters (about a city block) from the Earth. block) from the Earth.

Jupiter is 15 cm in diameter (the size of a large Jupiter is 15 cm in diameter (the size of a large grapefruit) and 5 blocks away from the Sun. grapefruit) and 5 blocks away from the Sun.

Saturn (the size of an orange) is 10 blocks away; Saturn (the size of an orange) is 10 blocks away; Uranus and Neptune (lemons) are 20 and 30 Uranus and Neptune (lemons) are 20 and 30

blocks away. blocks away. A human on this scale is the size of an atom; the A human on this scale is the size of an atom; the

nearest star would be over 40000 km away. nearest star would be over 40000 km away.

ClassificationClassification

PlanetsPlanets SatellitesSatellites AsteroidsAsteroids CometsComets

PlanetsPlanets

Big bodies Big bodies _______________ the the sunsun

SatellitesSatellites

_______________ - variously sized - variously sized objects orbiting the planetsobjects orbiting the planets

Callisto - Jupiter

Phobos - Mars

Ariel - Uranus

AsteroidsAsteroids

Small dense objects orbiting the Small dense objects orbiting the _______________

DactylIda

CometsComets

Small icy objects with highly Small icy objects with highly eccentric orbitseccentric orbits

Comet Hale Bop

Haley’s Comet

Other ClassificationOther Classification

CompositionComposition SizeSize Position relative to the sunPosition relative to the sun

CompositionComposition

_______________ or or rockyrocky planets: Mercury, planets: Mercury, Venus, Earth, and Mars: Venus, Earth, and Mars: The terrestrial planets are composed primarily of The terrestrial planets are composed primarily of

rock and metal and have relatively high densities, rock and metal and have relatively high densities, slow rotation, solid surfaces, no rings and few slow rotation, solid surfaces, no rings and few satellites. satellites.

_______________ or or gasgas planets: Jupiter, planets: Jupiter, Saturn, Uranus, and Neptune: Saturn, Uranus, and Neptune: The gas planets are composed primarily of The gas planets are composed primarily of

hydrogen and helium and generally have low hydrogen and helium and generally have low densities, rapid rotation, deep atmospheres, rings densities, rapid rotation, deep atmospheres, rings and lots of satellites. and lots of satellites.

PlutoPluto. .

SizeSize

_______________: Mercury, Venus, : Mercury, Venus, Earth, Mars and Pluto. Earth, Mars and Pluto.

_______________: Jupiter, Saturn, : Jupiter, Saturn, Uranus and Neptune. Uranus and Neptune.

Position Relative to the Position Relative to the SunSun

InnerInner planets planets: Mercury, Venus, Earth : Mercury, Venus, Earth and Mars. and Mars.

OuterOuter planets planets: Jupiter, Saturn, : Jupiter, Saturn, Uranus, Neptune and Pluto. Uranus, Neptune and Pluto.

The The _______________between Mars and between Mars and Jupiter forms the boundary between Jupiter forms the boundary between the inner solar system and the outer the inner solar system and the outer solar system. solar system.

SunSun

SunSun   The Sun is by far the The Sun is by far the

largest object in the solar largest object in the solar system. system.

It contains more than It contains more than 99.8% of the total mass of 99.8% of the total mass of the Solar System the Solar System

The Sun is, at present, The Sun is, at present, about 70% about 70% _______________and 28% and 28% _______________ by mass by mass and everything else and everything else amounts to less than 2%. amounts to less than 2%.

This changes slowly over This changes slowly over time as the Sun converts time as the Sun converts hydrogen to helium in its hydrogen to helium in its core. core.

SunSun   Conditions at the Sun's Conditions at the Sun's corecore are are

extreme. extreme. The temperature is 15.6 million Kelvin The temperature is 15.6 million Kelvin

and the pressure is 250 billion and the pressure is 250 billion atmospheres. atmospheres.

At the center of the core the Sun's At the center of the core the Sun's density is more than 150 times that of density is more than 150 times that of water. water.

SunSun

  The Sun's energy output is produced by The Sun's energy output is produced by _______________ reactions. reactions.

Each second about 700,000,000 tons of Each second about 700,000,000 tons of hydrogen are converted to about 695,000,000 hydrogen are converted to about 695,000,000 tons of helium and 5,000,000 tons of energy tons of helium and 5,000,000 tons of energy in the form of gamma rays. in the form of gamma rays.

As it travels out toward the surface, the As it travels out toward the surface, the energy is continuously absorbed and re-energy is continuously absorbed and re-emitted at lower and lower temperatures so emitted at lower and lower temperatures so that by the time it reaches the surface, it is that by the time it reaches the surface, it is primarily visible light. primarily visible light.

SunSun

  The surface of the Sun, called the The surface of the Sun, called the _______________, is at a temperature of , is at a temperature of about 5800 K. about 5800 K.

_______________ are "cool" regions, only are "cool" regions, only 3800 K (they look dark only by comparison 3800 K (they look dark only by comparison with the surrounding regions). with the surrounding regions). Sunspots can be very large, as much as 50,000 Sunspots can be very large, as much as 50,000

km in diameter. km in diameter. Sunspots are caused by complicated and not Sunspots are caused by complicated and not

very well understood interactions with the Sun's very well understood interactions with the Sun's magnetic field. magnetic field.

SunSun

      A small region known as the A small region known as the _______________lies above the lies above the photosphere. photosphere.

  The highly rarefied region above the The highly rarefied region above the chromosphere, called the chromosphere, called the _______________, extends millions of , extends millions of kilometers into space but is visible only kilometers into space but is visible only during eclipses (left). during eclipses (left). Temperatures in the corona are over Temperatures in the corona are over

1,000,000 K. 1,000,000 K.

Solar Flare/Quake

Fire Fountains

EclipsesEclipses

One consequence of the Moon's One consequence of the Moon's orbit about the Earth is that the orbit about the Earth is that the Moon can shadow the Sun's light as Moon can shadow the Sun's light as viewed from the Earth, or the Moon viewed from the Earth, or the Moon can pass through the shadow cast by can pass through the shadow cast by the Earth. the Earth.

The former is called a The former is called a _______________and the later is called and the later is called a a _______________. .

Types of Solar EclipsesTypes of Solar Eclipses

Total Solar EclipsesTotal Solar Eclipses occur when the umbra of occur when the umbra of the Moon's shadow touches a region on the the Moon's shadow touches a region on the surface of the Earth. surface of the Earth.

Partial Solar EclipsesPartial Solar Eclipses occur when the occur when the penumbra of the Moon's shadow passes over penumbra of the Moon's shadow passes over a region on the Earth's surface. a region on the Earth's surface.

Annular Solar EclipsesAnnular Solar Eclipses occur when a region occur when a region on the Earth's surface is in line with the on the Earth's surface is in line with the umbra, but the distances are such that the tip umbra, but the distances are such that the tip of the umbra does not reach the Earth's of the umbra does not reach the Earth's surface.surface.

Lunar EclipseLunar Eclipse

As we have noted in the preceding As we have noted in the preceding section, the Earth casts a shadow section, the Earth casts a shadow that the Moon can pass through. that the Moon can pass through.

When this happens we say that a When this happens we say that a _______________occurs. occurs.

Just as for solar eclipses, lunar Just as for solar eclipses, lunar eclipses can be partial or total, eclipses can be partial or total, depending on whether the light of the depending on whether the light of the Sun is partially or completely blocked Sun is partially or completely blocked from reaching the Moon. from reaching the Moon.

During a total lunar eclipse the During a total lunar eclipse the Moon takes on a dark red color Moon takes on a dark red color because it is being lighted slightly because it is being lighted slightly by sunlight passing through the by sunlight passing through the Earth's atmosphere and this light Earth's atmosphere and this light has the blue component has the blue component preferentially scattered out (this is preferentially scattered out (this is also why the sky appears blue from also why the sky appears blue from the surface of the Earth), leaving the surface of the Earth), leaving faint reddish light to illuminate the faint reddish light to illuminate the Moon during the eclipse. Moon during the eclipse.

MercuryMercury

Mercury is the Mercury is the _______________ planet planet to the Sun and the to the Sun and the eightheighth largest. largest.

Mercury is the Mercury is the _______________ densest major body in the solar densest major body in the solar system, after Earth.system, after Earth.

Mercury is often visible with Mercury is often visible with binoculars or even the unaided eye.binoculars or even the unaided eye.

Period = 88 daysPeriod = 88 days Length of Day = 58.6 Earth daysLength of Day = 58.6 Earth days

VenusVenus

VVeennuuss

Venus is second planet from the sun.Venus is second planet from the sun. Period = 88 daysPeriod = 88 days Length of Day = 58.6 Earth daysLength of Day = 58.6 Earth days Venus' orbit is the most nearly circular of Venus' orbit is the most nearly circular of

that of any planet.that of any planet. It is the brightest object in the sky except It is the brightest object in the sky except

for the Sun and the Moon. for the Sun and the Moon. Period = 225 days A Venusian day is 243 Earth days and is

longer than its year of 225 days. Venus rotates from _______________ to

_______________. To an observer on Venus, the Sun would rise in the west and set in the east.

  The pressure of Venus' atmosphere at the The pressure of Venus' atmosphere at the surface is 90 atmospheres (about the same surface is 90 atmospheres (about the same as the pressure at a depth of 1 km in Earth's as the pressure at a depth of 1 km in Earth's oceans). oceans).

It is composed mostly of It is composed mostly of _______________. . There are several layers of clouds many There are several layers of clouds many

kilometers thick composed of kilometers thick composed of _______________. These clouds completely . These clouds completely obscure our view of the surface. obscure our view of the surface.

This dense atmosphere produces a run-away This dense atmosphere produces a run-away greenhouse effect that raises Venus' surface greenhouse effect that raises Venus' surface temperature by about 400 degrees to over temperature by about 400 degrees to over 740 K (hot enough to melt lead). Venus' 740 K (hot enough to melt lead). Venus' surface is actually hotter than Mercury's surface is actually hotter than Mercury's despite being nearly twice as far from the despite being nearly twice as far from the Sun. Sun.

EarthEarth

Earth is the 3rd planet from the Sun at a distance of about 150 million kilometers (93.2 million miles).

It takes 365.256 days for the Earth to travel around the Sun and 23.9345 hours for the Earth rotate a complete revolution.

Earth is the only planet in the solar system known to harbor life.

Period = 365 days

Earth’s MoonEarth’s Moon

On _______________, Neil Armstrong became the first man to step onto the surface of the Moon. He was followed by Edwin Aldrin, both of the Apollo 11 mission.

Apollo 11 The Apollo 11 Lunar Module (LM) ascent stage, with Astronauts Neil A. Armstrong and Edwin E. Aldrin Jr. aboard, is photographed from the Command and Service Module (CSM) during rendezvous in lunar orbit. The LM was making its docking approach to the CSM. Astronaut Michael Collins remained with the CSM in lunar orbit while the other two crewmen explored the lunar surface. The large, dark-colored area in the background is Smyth's Sea, centered at 85 degrees east longitude and 2 degrees south latitude on the lunar surface (nearside). This view looks west. The Earth rises

above the lunar horizon. (Courtesy NASA)

MarsMars

Mars is the fourth planet from the Sun and is commonly referred to as the _______________.

The rocks, soil and sky have a red or pink hue.

In 1938, when Orson Welles broadcasted a radio drama based on the science fiction classic War of the Worlds by H.G. Wells, enough people believed in the tale of invading Martians to cause a near panic.

Period = 687 days Length of Day = 24.6 Earth hoursLength of Day = 24.6 Earth hours

Olympus MonsOlympus Mons Mons is about 600

km in diameter. The caldera on top of

____________(mons means mountain) is 24 kilometers above the surrounding plains on Mars.

Its caldera is 80 kilometers across. (Craters on volcanoes are called calderas).

JupiterJupiter

Jupiter is the fifth planet from the Sun and is the _______________ one in the solar system.

If Jupiter were hollow, more than one thousand Earths could fit inside.

There is a ring system, but it is very faint and is totally invisible from the Earth.

Period = 11.9 years Length of Day = 9 hours 55 minutes The _______________is a giant storm -

over 20,000 kilometers wide. Picture of the planet Jupiter's Great

Red Spot taken by Voyager 1. We know that the Great Red Spot existed for at least the last 300 years. The Great Red Spot is the ______________________________in our solar system.

Colorful latitudinal bands, atmospheric clouds and storms illustrate Jupiter's dynamic weather systems. The cloud patterns change within hours or days. The Great Red Spot is a complex storm moving in a _______________ direction.

SaturnSaturn

Saturn is the sixth planet from the Sun and is the _______________largest in the solar system.

Saturn is visibly flattened at the poles, a result of the very fast rotation of the planet on its axis.

Its day is 10 hours, 39 minutes long, and it takes 29.5 Earth years to revolve about the Sun.

Period = 29.5 years Length of Day = 10 hours 40

minutes

The wind blows at high speeds on Saturn. Near the equator, it reaches velocities

of 500 meters a second (1,100 miles an hour). The wind blows mostly in an easterly direction. The strongest winds are found near the equator and velocity falls off uniformly at higher latitudes.

UranusUranus

Uranus is the seventh planet from the Sun and is the third largest in the solar system.

Orbits the Sun once every 84.01 Earth years.

The length of a day on Uranus is 17 hours 14 minutes.

The atmosphere of Uranus is composed of 83% hydrogen, 15% helium, 2% methane and small amounts of acetylene and other hydrocarbons. _______________ in the upper atmosphere absorbs red light, giving Uranus its blue-green color.

Uranus is distinguished by the fact that it is tipped on its side.

Period = 84.1 years Length of Day = 17 hours 14

minutes

NeptuneNeptune

Neptune is the outermost planet of the gas giants.

The first two thirds of Neptune is composed of a mixture of molten rock, water, liquid ammonia and methane. The outer third is a mixture of heated gases comprised of hydrogen, helium, water and methane.

Methane gives Neptune its blue cloud color.

Neptune is a dynamic planet with several large, dark spots reminiscent of Jupiter’s hurricane-like storms. The largest spot, known as the _______________, is about the size of the earth and is similar to the Great Red Spot on Jupiter.

The strongest winds on any planet were measured on Neptune. Most of the winds there blow westward, opposite

to the rotation of the planet. Near the Great Dark Spot, winds blow up to 2,000 kilometers (1,200 miles) an hour.

Period = 164.8 Earth years Length of Day = 16 hours

PlutoPluto

Pluto remains the only planet that has not been visited by a spacecraft.

Pluto is usually farther from the Sun than any of the nine planets. however, due to the eccentricity of its

orbit, it is closer than Neptune for 20 years out of its 249 year orbit.

Pluto crossed Neptune's orbit January 21, 1979, made its closest approach September 5, 1989, and remained within the orbit of Neptune until February 11, 1999.

This will not occur again until September 2226.

Pluto's rotation period is 6.387 days, the same as its satellite _______________.

Period = 248.8 years Length of Day = 6.4 Earth days Although it is common for a satellite to

travel in a synchronous orbit with its planet, Pluto is the only planet to rotate synchronously with the orbit of its satellite. Thus being tidally locked, Pluto and Charon

continuously face each other as they travel through space.