Chapter 22Chapter 22Exploring SpaceExploring Space

Electromagnetic RadiationElectromagnetic Radiation

What is it ???What is it ???– Radio wavesRadio waves– Visible lightVisible light– Gamma raysGamma rays– X-raysX-rays– Ultraviolet lightUltraviolet light– Infrared wavesInfrared waves– MicrowavesMicrowaves

Electromagnetic SpectrumElectromagnetic Spectrum

FrequencyFrequency

Forms of electromagnetic radiation differ in Forms of electromagnetic radiation differ in their frequencies.their frequencies.

FrequencyFrequency: # of wave crests that pass a : # of wave crests that pass a given point per unit of time.given point per unit of time.

The shorter the wavelength, the higher the The shorter the wavelength, the higher the frequency.frequency.

Speed of LightSpeed of Light

300,000 km/s300,000 km/s

ALL electromagnetic waves travel ALL electromagnetic waves travel at this speed in a vacuum (where at this speed in a vacuum (where there is no matter)there is no matter)

First to Use a Telescope to Study First to Use a Telescope to Study the Skythe Sky

Galileo in 1600’sGalileo in 1600’s

Optical TelescopeOptical TelescopeUse light to produce magnified images.Use light to produce magnified images.– Refracting telescope: convex lensesRefracting telescope: convex lenses– Reflecting telescope: concave mirror.Reflecting telescope: concave mirror.

ObservatoryObservatoryWhere optical telescopes are located.Where optical telescopes are located.

Edwin P. HubbleEdwin P. HubbleDiscovered: Universe is ExpandingDiscovered: Universe is Expanding

Hubble Space Telescope named after him.Hubble Space Telescope named after him.

Hubble Space TelescopeHubble Space Telescope

Located outside Earth’s atmosphereLocated outside Earth’s atmosphere

Hubble TelescopeHubble Telescope

Hubble PicturesHubble Pictures

Radio TelescopeRadio Telescope

Studies radio waves that travel through Studies radio waves that travel through space.space.

Useful 24 hoursUseful 24 hours

a day.a day.

Early Space MissionsEarly Space Missions

Allowed astronomers Allowed astronomers to study space in to study space in ways not possible ways not possible using telescopes.using telescopes.

Made possible by Made possible by rockets.rockets.

SatelliteSatellite

Any object that Any object that revolves around revolves around another object another object in an orbitin an orbit

In 1957 the formerIn 1957 the formerSoviet Union Soviet Union launched first artificiallaunched first artificial satellite: Sputnik I.satellite: Sputnik I.

Satellites TodaySatellites Today

Thousands of artificial Thousands of artificial satellites orbit Earthsatellites orbit Earth

Used for: Used for: communication and communication and weather forecasting.weather forecasting.

Space ProbesSpace Probes

Do not orbit EarthDo not orbit Earth

Travel through space.Travel through space.

Space Probes: Pioneer 10Space Probes: Pioneer 10

Launched 1972Launched 1972

11stst manmade object manmade object

to travel through to travel through

asteroid belt.asteroid belt.

Transmitter Transmitter

failed in 2003failed in 2003

Passed PlutoPassed Pluto

Space Probes: Voyager I & IISpace Probes: Voyager I & IILaunched by U.S. in 1977Launched by U.S. in 1977

Expected to collect data until 2020Expected to collect data until 2020

SaturnSaturnTaken by Voyager II1981

Images from Voyager Space Images from Voyager Space ProbesProbes

Voyager 2: 1981Rings of Saturn

Images from Voyager Space Images from Voyager Space ProbesProbes- Voyager 2

- 1989- Neptune

Voyager 1990Voyager 1990

By 1990, Voyager 1 was farther from the By 1990, Voyager 1 was farther from the Sun than Pluto, and approximately 4 billion Sun than Pluto, and approximately 4 billion miles from the Earth. Thus, NASA gave miles from the Earth. Thus, NASA gave Voyager 1 one last assignment and had Voyager 1 one last assignment and had the craft take the first ever pictures of the the craft take the first ever pictures of the planets from “outside” the solar system. planets from “outside” the solar system. This is a compilation of those shots. This is a compilation of those shots.

Images from Voyager Space Images from Voyager Space ProbesProbes

Space Probe: GalileoSpace Probe: Galileo

Launched in 1989Launched in 1989

Reached Jupiter in 1995Reached Jupiter in 1995

Released smaller probe to approach Released smaller probe to approach Jupiter.Jupiter.

Studied Europa and Io (Jupiter’s moons)Studied Europa and Io (Jupiter’s moons)

Moon QuestMoon Quest

Yuri Gagarin: 1Yuri Gagarin: 1stst man in space (Soviet) man in space (Soviet)

Project Mercury: began U.S. mission to Project Mercury: began U.S. mission to put a man in space.put a man in space.

1961: Alan Shepard: 11961: Alan Shepard: 1stst U.S. man in U.S. man in spacespace

1962: John Glenn: 11962: John Glenn: 1stst U.S. citizen to orbit U.S. citizen to orbit EarthEarth

Men in SpaceMen in Space

Yuri Gagarin1st man to orbit Earth

Men in SpaceMen in Space

Alan Shepherd John Glenn

Project GeminiProject Gemini

Teams of 2 Teams of 2 astronauts in the astronauts in the same Gemini same Gemini spacecraft orbited spacecraft orbited Earth. One Gemini Earth. One Gemini team met and team met and connected with connected with another spacecraft in another spacecraft in orbit.orbit.

Robotic Probes Sent to the MoonRobotic Probes Sent to the Moon

RangerRanger

Surveyor: Surveyor: landed on moon in 1966landed on moon in 1966

Lunar Orbiter: Lunar Orbiter: took pictures of moon’s took pictures of moon’s surfacesurface

Project ApolloProject Apollo

1969: Apollo II 1969: Apollo II landed on the Moonlanded on the Moon

Neil Armstrong: 1Neil Armstrong: 1stst person to step on person to step on MoonMoon

Space StationsSpace Stations

1973: U.S. launched Skylab1973: U.S. launched Skylab– Fell out of orbit in 1979 Fell out of orbit in 1979

Space StationsSpace Stations

MirMir– Soviet UnionSoviet Union– Dr. Valery Polyakov Dr. Valery Polyakov

spent 438 days in spent 438 days in space studying the space studying the long-term effects of long-term effects of weightlessness.weightlessness.

International Space StationInternational Space Station

Effort of 16 nationsEffort of 16 nations

3 phases3 phases

Should be completed Should be completed by 2006by 2006

Missions to MarsMissions to Mars

Mars Global Surveyor: orbited Mars and Mars Global Surveyor: orbited Mars and took pictures.took pictures.

Pathfinder: descended to surface of MarsPathfinder: descended to surface of Mars

Mars Odyssey: mapping surface of MarsMars Odyssey: mapping surface of Mars

Spirit and Opportunity: rovers launched in Spirit and Opportunity: rovers launched in 2003: goal to analyze surface of mars2003: goal to analyze surface of mars

Future plans: Phoenix 2008Future plans: Phoenix 2008

CassiniCassini

Launched 1997Launched 1997

Destination: SaturnDestination: Saturn