Chapter 24 Notes:

Unit I: Lunar Exploration

• The moon is 386,000 km away from us!
• First spacecraft to fly passed the moon was in 1959 (non-human)

Entering a Rocket to the Moon:

• Must be large enough to lift out of the earth’s atmosphere.
• Once in orbit, another rocket must fire the craft towards the moon.
• Spacecraft must be fired toward the position the moon will be when the craft gets to the moon.
• Because the moon moves around the earth, the rockets path must be curved to compensate for the movement.

History of Space travel:

The Luna series: (unmanned probes)

• Russian built
• Luna 1 = first successful fly-by of the moon
• Luna 2 = crashed into the moon! Oops!
• Luna 3 = Orbited the moon and returned photos of the front and back of moon’s surface.

Pioneer series: (unmanned probes)

• United States built
• Pioneer 1, 2, and 3 were unsuccessful
• Pioneer 4 escaped earth’s pull and returned photos as it passed the moon.

President Kennedy made it a national goal in 1961 to have a man on the moon by the end of the decade!

Russia was the first country to have an astronaut (cosmonaut) orbit the earth for 25 hours.

Ranger and Surveyor Probes:

• designed to find a perfect landing site.
• Ranger was designed to send back various lunar photos for consideration
• Surveyor was designed to land on the moon and take soil samples to find the perfect site for landing

First manned spacecraft:

• Mercury rockets = 9 missions to launch an astronaut into orbit. Only one astronaut in each rocket.
• John Glenn was first to orbit earth!
• Alan Shepard was first into space!
• Gemini rockets = rockets designed for two astronauts.
• Ten missions were designed to answer 2 questions: #1 Could a human survive in weightlessness? …and #2 Could we maneuver spacecraft in space?
• Apollo rockets = designed to send 3 astronauts to the moon, allowing two of them to walk on the lunar surface.
• Apollo 1 = Caught fire on the launch pad, killing all three astronauts!
• Apollo 2 = (AS-201) Unmanned suborbital flight to test the rocket’s command and service modules.
• Apollo 3 = (AS-202) Also unmanned suborbital flight to test the rocket’s command and service modules.
• Apollo 4 = Unmanned first all-up test of the three stages of the Saturn V rocket!
• Apollo 5 = Unmanned first test of the lunar module in space conditions.
• Apollo 6 = Final unmanned test flight of the Saturn V rocket for Apollo missions.
• Apollo 7 = First manned flight of Apollo missions designed to simply orbit the earth and perform maneuvering tests.
• Apollo 8 = First mission designed to orbit the moon!
• Apollo 9 = Orbited the earth and practiced the attaching and detaching of the lunar and command modules.
• Apollo 10 = Orbited the moon and practiced the landing of the lunar module on the surface of the moon. Did not actually make a full lunar landing.
• Apollo 11 = Allowed Neil Armstrong and Buzz Aldrin to walk on the moon.
• Apollo 12 = Allowed Pete Conrad and Alan Bean to walk on the moon.
• Apollo 13 = First space mission to nearly become a disaster in space. Successfully made it back to earth.
• Apollo 14 = Allowed Alan Shepard and Ed Mitchell to walk on the moon.
• Apollo 15 = Allowed David Scott and Jim Irwin to RIDE on the moon with the first lunar rover (car) on the moon!
• Apollo 16 = Allowed John Young and Charlie Duke to walk on the moon.
• Apollo 17 = Last mission that allowed Gene Cernan and Harrison Schmitt to walk on the moon.

Apollo rocket composition:

• Command module – module that contained the three astronauts and all controls to operate the rocket
• Service module – module that contains all the electrical systems for the rocket
• Lunar module – module used to travel from the Apollo rocket down to the lunar surface and back to the rocket again
• Three stages of launch rockets – consisted of rocket engines and large fuel tanks that were slowly jettisoned (thrown off) as the craft made its way from the launch pad to space to the moon.
• Apollo rocket was 110 meters tall when sitting on the launch pad!
• The command module is the ONLY part to return to earth after the mission is over!

The Space Shuttle:

• Obviously a spacecraft that was designed to be re-used.
• Designed to mimic the physics that allow an airplane to fly. Capable of making smooth landings back on earth.
• Contains two solid rocket boosters and one large fuel tank to fuel the rocket boosters during take-off.
• All external parts are jettisoned once the rocket enters or nears earth’s orbit
• The space shuttle operates on liquid hydrogen and oxygen mixture
• Every mission in space since 1980 has been to explore more unknown facts about space life and travel
• Shuttle missions have included:

• Galileo
• Magellan
• Hubble Space Telescope
• Ulysses
• Gamma Ray Observatory
• Spacelab
• International Space Station

The Apollo program included a large number of uncrewed test missions and 12 crewed missions: three Earth orbiting missions, two lunar orbiting missions (8 & 10), a lunar swingby (13), and six Moon landing missions (11, 12, 14, 15, 16, & 17). Two astronauts from each of the six missions walked on the moon. Total funding of the Apollo program was approximately $20,443,600,000 !!!

 

 

Unit II: Properties of the Moon

Moon’s diameter = 3476km (1/4 earth dia.)

Moon’s mass = 1/80 that of earth

Moon’s gravity = 1/6 that of earth

• Seismic readings sent from the moon’s surface tell us it is made up of a thick crust and mantle and may contain a minor amount of heat in an unknown central core???
• The moon turns on its axis at the same period it rotates around the Earth = the same side of the moon always faces earth!!!

Lunar Surface:

• Dark areas are lunar lowlands
• Light areas are lunar highlands
• The low areas were thought to be filled with water and were called "maria"
• In fact, there is NO water on the moon
• Lunar surface is actually "egg-shaped" because of the pull received from earth!
• Lunar surface is now pock-marked with craters formed from micrometeoriods, no larger than sand grains
• Dating lunar rocks put the moon at about 4.3 billion years old….a little younger than earth!
• Long clefts or cracks in the lunar surface are called "Rilles".
• Lunar soil is called "Regolith" which means ‘loose rock material’. Kind of grayish-brown in color and quite fine in texture.
• Regolith ranges in thickness from about 1 to 20 meters.

The Moon’s Motions:

• Moon revolves around the sun from west to east.
• Its period is about 27 ¼ days
• Its average distance is about 386,000 km
• When the moon is closest to earth it is called ‘perigee’.
• When the moon is farthest from earth it is called ‘apogee’.
• The moon goes through monthly "phases" in which it changes in appearance on a daily basis.
• Moon change = dark to light – waxing
• Moon change = light to dark – waning
• Lunar eclipse – occurs when the earth is blocking the sun’s light from hitting the moon! Happens every ~28 days.
• Solar eclipse – occurs when the moon is blocking the sun from hitting the earth! Happens ‘partially’ every year; totally at one point on earth about every 300 or more years.