chapter 22
TRANSCRIPT
Chapter 22Chapter 22Exploring SpaceExploring Space
Electromagnetic waves carry Electromagnetic waves carry energy through space and energy through space and matter.matter.
Electromagnetic radiation Electromagnetic radiation includes radio waves, visible includes radio waves, visible light, gamma rays, X rays, light, gamma rays, X rays, ultraviolet light, infrared waves ultraviolet light, infrared waves and microwaves.and microwaves.
Electromagnetic spectrum –Electromagnetic spectrum –electromagnetic radiation electromagnetic radiation arranged by wavelengtharranged by wavelength
Forms of electromagnetic Forms of electromagnetic radiation differ in their radiation differ in their frequencies –the number of frequencies –the number of wave crests that pass a given wave crests that pass a given point per unit time.point per unit time.
• The shorter the wavelength, the The shorter the wavelength, the higher the frequency.higher the frequency.
Optical telescopes –use light to Optical telescopes –use light to produce magnified images.produce magnified images.
Refracting telescopes –have Refracting telescopes –have convex lensesconvex lenses
Reflecting telescope –uses Reflecting telescope –uses concave mirror.concave mirror.
Optical telescopes are often Optical telescopes are often located in buildings called located in buildings called observatories, which often observatories, which often have roofs that can be opened have roofs that can be opened for viewing.for viewing.
The Hubble Space Telescope, is The Hubble Space Telescope, is located outside Earth’s located outside Earth’s atmosphere.atmosphere.• Mistake made in shaping largest Mistake made in shaping largest
mirrormirror
• Once the mistake was repaired in Once the mistake was repaired in 1999, the Hubble Space Telescope 1999, the Hubble Space Telescope sent back images of a large cluster of sent back images of a large cluster of galaxies.galaxies.
Radio telescope –studies radio Radio telescope –studies radio waves that travel through waves that travel through space.space.
• Because radio waves pass freely Because radio waves pass freely through Earth’s atmosphere, radio through Earth’s atmosphere, radio telescopes are usually useful 24 telescopes are usually useful 24 hours a day.hours a day.
• Scientists use information from radio Scientists use information from radio waves to detect objects in space, waves to detect objects in space, map the universe, and look for signs map the universe, and look for signs of life on other planets.of life on other planets.
Section 2: Early Space Section 2: Early Space MissionsMissions
Early space missions allowed Early space missions allowed astronomers to study space in astronomers to study space in ways not possible using ways not possible using telescopestelescopes
Special motors that don’t Special motors that don’t require air are called rockets.require air are called rockets.
A satellite –any object that A satellite –any object that revolves around another object revolves around another object in an orbit, or curved path.in an orbit, or curved path.
In 1957 the former Soviet In 1957 the former Soviet Union launched the first Union launched the first artificial satellite, Sputnik I.artificial satellite, Sputnik I.
Today thousands of Today thousands of communication, scientific, and communication, scientific, and weather satellites orbit Earth.weather satellites orbit Earth.
A space probe gathers and A space probe gathers and transmits information to Earth.transmits information to Earth.
Voyager 1 and Voyager 2 are Voyager 1 and Voyager 2 are exploring space beyond the exploring space beyond the solar system.solar system.
Pioneer 10, first probe to travel Pioneer 10, first probe to travel through an asteroid belt.through an asteroid belt.
Galileo, launched in 1989, Galileo, launched in 1989, studied Jupiter and two of its studied Jupiter and two of its moons, Europa and Io.moons, Europa and Io.
United States began race for United States began race for the Moon in the 1960s.the Moon in the 1960s.
First step in program to reach First step in program to reach the Moon began with Project the Moon began with Project Mercury.Mercury.
In 1961, Alan B. Shepard In 1961, Alan B. Shepard became the first U.S. citizen in became the first U.S. citizen in space.space.
In 1962, John Glenn became In 1962, John Glenn became the first U.S. citizen to orbit the first U.S. citizen to orbit Earth.Earth.
Second step in the Moon race Second step in the Moon race involved project Gemini.involved project Gemini.
• Teams of astronauts met and Teams of astronauts met and connect with orbiting spacecraft.connect with orbiting spacecraft.
• Effects of space travel on humans Effects of space travel on humans studied.studied.
Project Apollo –the final step in Project Apollo –the final step in U.S. program to reach the U.S. program to reach the Moon.Moon.• On July 20, 1969, Apollo 11 landed on On July 20, 1969, Apollo 11 landed on
the Moon’s surface, and Neil the Moon’s surface, and Neil Armstrong and Edwin Aldrin became Armstrong and Edwin Aldrin became the first two people to set foot on the the first two people to set foot on the Moon.Moon.
Section 3: Current and Future Section 3: Current and Future Space MissionsSpace Missions
Space shuttle: reusable Space shuttle: reusable spacecraft for transporting spacecraft for transporting people, satellites, and other people, satellites, and other materials to and from space.materials to and from space.• Launched standing on end.Launched standing on end.
• Glides back to Earth like an airplane.Glides back to Earth like an airplane.
Space stations –permanent Space stations –permanent places in space for humans to places in space for humans to live and work.live and work.
U.S. Skylab orbited Earth from U.S. Skylab orbited Earth from 1973-1979.1973-1979.
• Crews performed experiments and Crews performed experiments and collected data on the effects of living collected data on the effects of living in space.in space.
• Fell out of orbit and burned up as it Fell out of orbit and burned up as it entered the atmosphere.entered the atmosphere.
Former Soviet Union Mir Former Soviet Union Mir housed one socmonaut for housed one socmonaut for more than a year at a time.more than a year at a time.
The United States and Russia The United States and Russia have cooperated in nine joint have cooperated in nine joint space missions.space missions.
International Space Station –International Space Station –cooperation and resources of cooperation and resources of 16 countries.16 countries.• ISS to be completed by 2006ISS to be completed by 2006
Several missions explore Several missions explore MarsMars
• Mars Global Surveyor and Mars Mars Global Surveyor and Mars Pathfinder –scientists learned water Pathfinder –scientists learned water may have covered planet in the past.may have covered planet in the past.
In 2002, Odyssey confirmed In 2002, Odyssey confirmed that Martian soil contained that Martian soil contained frozen water.frozen water.