2. SatellitesSatellites
Satellite: Any body thatSatellite: Any body that orbitsorbits aa
larger bodylarger body
1957: First artificial satellite,1957: First artificial satellite,
Sputnik,Sputnik, launched by the Sovietslaunched by the Soviets
Earth’s onlyEarth’s only naturalnatural satellite is thesatellite is the
moon.moon.
3. The MoonThe Moon
Force of gravity is 1/6Force of gravity is 1/6thth
that ofthat of
Earth’sEarth’s
4. Lack of atmosphere also means that
there is a huge temperature range:
134o
C in the day, -170o
C at night
Very little gravity so it has no atmosphere;Very little gravity so it has no atmosphere;
therefore it has no weathertherefore it has no weather
5. The MoonThe Moon
Your weight wouldYour weight would
change, but notchange, but not
your massyour mass
6. The MoonThe Moon
1969-1972: The US sent 61969-1972: The US sent 6 ApolloApollo
missions to the moonmissions to the moon
7. Moon rotates once every 27.3 days, but appears to take 29.5 days.
It needs time to “catch up” from the delay crated by the rotation of the
earth
8. The Lunar SurfaceThe Lunar Surface
From youngest to oldest -From youngest to oldest -
Rilles : collapsed lava tubesRilles : collapsed lava tubes
Maria: dark areas on the moon;Maria: dark areas on the moon;
made of solidified lavamade of solidified lava
– Remains of ancient volcanoesRemains of ancient volcanoes
– Looks like riverbeds but no water everLooks like riverbeds but no water ever
on moonon moon
Highlands: light areas; created fromHighlands: light areas; created from
meteorites hitting the moonmeteorites hitting the moon
11. The Lunar SurfaceThe Lunar Surface
Craters: bowl-shaped depressions,Craters: bowl-shaped depressions,
most from the moons earlymost from the moons early
formation; named for famousformation; named for famous
scientistsscientists
Rays: streaks that extend from theRays: streaks that extend from the
impact sitesimpact sites
– Most formed 4 billion of years ago from debris
that bombarded all other bodies in solar
system
14. Lunar RocksLunar Rocks
regolithregolith - layer of dust and ground- layer of dust and ground
up rock created from meteoriteup rock created from meteorite
impactsimpacts
Moons rocks are similar to EarthMoons rocks are similar to Earth
rocks –rocks –
silicatessilicates
15. Galileo Was RightGalileo Was Right
From the Earth to the Moon: Part 10From the Earth to the Moon: Part 10
– Gathering of lunar rocksGathering of lunar rocks
16. Interior of the MoonInterior of the Moon
Information found usingInformation found using
seismographsseismographs
Less dense than the interior of theLess dense than the interior of the
EarthEarth
– Density = mass / volumeDensity = mass / volume
17. Interior of the MoonInterior of the Moon
Crust is thinner on the Earth-facingCrust is thinner on the Earth-facing
sideside
Mantle pulled closer on Earth-Mantle pulled closer on Earth-
facing side when ancient magmafacing side when ancient magma
below surface existed – makingbelow surface existed – making
crust thinnercrust thinner
18.
19. Interior of the MoonInterior of the Moon
Core – made of ironCore – made of iron
Determined the iron is solid, unlike Earth’sDetermined the iron is solid, unlike Earth’s
core, because it is not magneticcore, because it is not magnetic
Lack of magnetism is due to lack ofLack of magnetism is due to lack of
convectionconvection
21. Current Theory of Moon’sCurrent Theory of Moon’s
CreationCreation
Giant impact theory: formed whenGiant impact theory: formed when
a Mars-sized object struck thea Mars-sized object struck the
EarthEarth
– Fragments ejected from the EarthFragments ejected from the Earth
(mostly less dense crust and mantle)(mostly less dense crust and mantle)
– Eventually formed moonEventually formed moon
Explains why the moon is lessExplains why the moon is less
dense than the Earthdense than the Earth
23. Impact TheoryImpact Theory
Supported by moon rocksSupported by moon rocks
– Anothrocite – “Genisis Rock”Anothrocite – “Genisis Rock”
– Chemical analysis of the Genesis Rock
indicated it is an anorthosite, composed
mostly of a type of plagioclase feldspar
– formed in the early stages of the solar system,
at least 4 billion years ago.
– recovered in a crater of the Moon, near other
rocks of its kind.
25. Impact TheoryImpact Theory
11stst
phase: Mars-sized object struckphase: Mars-sized object struck
the Earththe Earth
22ndnd
phase: moon was covered withphase: moon was covered with
molten lava – densest materialmolten lava – densest material
moved to the centermoved to the center
33rdrd
phase: meteorite impactphase: meteorite impact
“punches” through thin crust; liquid“punches” through thin crust; liquid
rock seeps throughrock seeps through
Current phase: less loose materialCurrent phase: less loose material
in solar system; only rayed cratersin solar system; only rayed craters
28. New Theory (2012)New Theory (2012)
Impact of Mars-sizedImpact of Mars-sized meteoritemeteorite (Theia)(Theia) notnot
likelylikely
New study of samples of the Moon areNew study of samples of the Moon are
virtually identical with the Earthvirtually identical with the Earth
Studied titanium isotopesStudied titanium isotopes
Meteorite sample shown extremelyMeteorite sample shown extremely
diverse titanium isotope compositiondiverse titanium isotope composition
29. New Theory (2012)New Theory (2012)
Scientists theorize that Theia might haveScientists theorize that Theia might have
been made solely of icebeen made solely of ice
Or that a proto-Earth was spinning muchOr that a proto-Earth was spinning much
faster, allowing more mixing offaster, allowing more mixing of
compositioncomposition
Editor's Notes
Mass is the amount of matter in an object
NASA Nation al Aeronautics and Space Administration
Apollo (1961 to 1972) was the third US human spaceflight program
Project Mercury (one man), conceived during President Eisenhower, sent the first man in to space
Project Gemini (two man) 1962 to 1966 – support the Apollo missions
Moon orbits 27.3 days as compared to distant stars
2 additional days are needed to “catch up” because the earth is not stationary. The movement of the earth puts the moon a little behind its real location because the earth revolves in the same direction as the moon
The earth travels 0.075 of its circuit around the sun in 27.3 days. That causes a difference between the orbit seen on earth verses the orbit seen from space
Rilles is German for groove
Sinous rilles – meander in a curved path like a mature river – remains of collapsed lava tubes – remains controversial
Arcuate rilles – have a smooth curve and are found along the dark edges of maria – made when lava flowed, cooled and contracted and sunk
Straight rilles – follow long linear paths – created by sections of crust sunken between two parallel faults
