astronomy 101 the solar system tuesday, wednesday, thursday · •volume = 4/3*π*r3 = 5.23 x 10...
TRANSCRIPT
Astronomy 101The Solar System
Tuesday, Wednesday, Thursday
Astronomy 101The Solar System
Tuesday, Wednesday, Thursday
Shaping Planetary Surfaces
• Impact Cratering• Volcanism• Tectonics• Tectonics• Erosion
Shaping Planetary Surfaces
Cratering
Meteor Crater, Arizona
http://www.solarviews.com/eng/tercrate.htm
Cratering
Meteor Crater, Arizona
http://www.solarviews.com/eng/tercrate.htm
Galle Crater, MarsGalle Crater, Mars
Mercury
http://geologyindy.byu.edu/eplanet/chapter_5.htm
Mercury
http://geologyindy.byu.edu/eplanet/chapter_5.htm
Callisto (Moon of Jupiter)
http://ase.tufts.edu/cosmos/view_picture.asp?id=726
Callisto (Moon of Jupiter)
http://ase.tufts.edu/cosmos/view_picture.asp?id=726
VolcanismVolcanism
Erosion
• Processes that break down or transport rock through the action of ice, liquid, or gas
• Movement of glaciers• Movement of glaciers• Formation of canyons by running water• Shifting of sand dunes by wind
Erosion
Processes that break down or transport rock through the action of ice, liquid, or gas
Formation of canyons by running waterShifting of sand dunes by wind
Energy of Impact (K
• v = 17 km/s• Density = 3,000 kg/m3
• Diameter = 2*radius =10 km• Volume = 4/3*π*r3 = 5.23 x 10• Mass = density*volume• Mass = 1.57 x 1015 kg• Kinetic energy = ½ mv2
• Kinetic energy = 2.27 x 1023
• Kinetic Energy = 5.42 x 107
• Largest Nuclear Bomb is 100 Megatons of TNT
Energy of Impact (K-T)
Diameter = 2*radius =10 km= 5.23 x 1011 m3
23 Joules7 Megatons of TNT
Largest Nuclear Bomb is 100 Megatons of TNT
Gene Shoemaker
Parts taken from talk of Bridget Mahoney
Gene Shoemaker
Parts taken from talk of Bridget Mahoney
Meteor Crater, Flagstaff, Arizona
• Shoemaker wrote his Ph.D thesis on Meteor Crater
• Shoemakmechanics of meteorite impacts
Shoemaker wrote his Ph.D thesis on Meteor Crater
emaker did seminal research in the mechanics of meteorite impacts
Meteor Crater and Shoemaker
• In 1952, ShMeteor Crater as well as lunar craters were created by asteroidal impactswere created by asteroidal impacts
• USGS sent Shoemaker to the Yucca flats to inveto compare with Meteor Crater,
Shoemaker at Meteor Crater, 1960’s
Meteor Crater and Shoemaker
52, Shoemaker hypothesized that Meteor Crater as well as lunar craters were created by asteroidal impactswere created by asteroidal impactsUSGS sent Shoemaker to the Yucca
to investigate small nuclear events to compare with Meteor Crater,
Quartz (SiOQuartz (SiO2)
Coesite
• While doing meteorite impdiscovered Coesite
• Coesite (SiOproduced during violent impact
• Different crystal structure than quartzearth.leeds.ac.uk
Coesite
doing research in the Yucca flats on ite impact with David Chao, the pair
discovered Coesite(SiO2) is a mineral that is
produced during violent impact Different crystal structure than quartz
Chixculub Crater
Taken from presentation by Amanda Baker
Chixculub Crater
Taken from presentation by Amanda Baker
K-T Boundary
• 65 million years ago• Boundary in the rock
record separating the Cretaceous and Tertiary Cretaceous and Tertiary Periods
• Corresponds to one of the greatest mass extinctions in history
• Global layer of clay separating the two periods
• First proposed by Walter Alvarez
T Boundary
We know it happened but where?•
We know it happened but where?A Circular geophysical anomaly, now known to define the Chicxulub structure, was originally identified on the northern identified on the northern edge of the Yucatan Peninsula during oil surveys in the 1950's.
Chixculub• Translates to “tail of the devil” in Mayan• The meteorite's estimated size was about 10 km (6 mi) in
diameter, releasing an estimated 4.3(equivalent to 191,793 gigatons of TNT) on impact.
ChixculubTranslates to “tail of the devil” in MayanThe meteorite's estimated size was about 10 km (6 mi) in diameter, releasing an estimated 4.3×1023 joules of energy (equivalent to 191,793 gigatons of TNT) on impact.
Data• Seismic, gravity and magnetic
data define a structure ~180 km in diameter.
Data
What happened?
• An asteroid roughly 10 km (6 miles) across hit Earth about 65 million years ago.
• This impact made a huge explosion and a crater about • This impact made a huge explosion and a crater about 180 km (roughly 110 miles) across.
• Debris from the explosion was thrown into the atmosphere, severely altering the climate, and leading to the extinction of roughly 60% of species that existed at that time, including the dinosaurs.
What happened?
An asteroid roughly 10 km (6 miles) across hit Earth about 65 million years ago.
This impact made a huge explosion and a crater about This impact made a huge explosion and a crater about 180 km (roughly 110 miles) across.
Debris from the explosion was thrown into the atmosphere, severely altering the climate, and leading to the extinction of roughly 60% of species that existed at that time, including the dinosaurs.
Environmental Damage
• http://www4.tpgi.com.au/users/horsts/climate.htm
Environmental Damage
http://www4.tpgi.com.au/users/horsts/climate.htm
• The worst hit organisms were those in the oceans.• On land, the Dinosauria of course went extinct,
along with the Pterosauria. • Mammals and most non-
seemed to be relatively unaffected. • The terrestrial plants suffered to a large extent,
except for the ferns, which show an apparently dramatic increase in diversity at the Kboundary, a phenomenon known as the fern spike.
The worst hit organisms were those in the oceans.On land, the Dinosauria of course went extinct, along with the Pterosauria.
- dinosaurian reptiles seemed to be relatively unaffected. The terrestrial plants suffered to a large extent, except for the ferns, which show an apparently dramatic increase in diversity at the K-T boundary, a phenomenon known as the fern spike.
• Pterosaurs were flying reptilesPterosaurs were flying reptiles
• Dinosaurs lived during the Mesozoic Era, from • Dinosaurs lived during the Mesozoic Era, from late in the Triassic period (about 225 million years ago) until the end of the Cretaceous (about 65 million years ago).
Dinosaurs lived during the Mesozoic Era, from Dinosaurs lived during the Mesozoic Era, from late in the Triassic period (about 225 million years ago) until the end of the Cretaceous (about 65
• Modern birds are considered to be the direct descendants of dinosaurs
Modern birds are considered to be the direct descendants
Tunguska • Occurred in 1908• Huge explosion in the atmosphere• Thought to be asteroid or comet that exploded in
mid-air 6 to 10 kilometers above the Earth's surface surface
• Energy of 10 and 15 megatons of TNT• Equivalent to the most powerful nuclear bomb
detonated in the USA• There wasn’t a large expedition to the site until
1927
Tunguska
Huge explosion in the atmosphereThought to be asteroid or comet that exploded in
air 6 to 10 kilometers above the Earth's
Energy of 10 and 15 megatons of TNTEquivalent to the most powerful nuclear bomb
There wasn’t a large expedition to the site until
http://en.wikipedia.org/wiki/Image:Tunguska_event_fallen_trees.jpghttp://en.wikipedia.org/wiki/Image:Tunguska_event_fallen_trees.jpg
http://thunderbolts.info/tpod/2006/image06/060203tunguska2.jpghttp://thunderbolts.info/tpod/2006/image06/060203tunguska2.jpg
•http://geophysics.ou.edu/impacts/tunguska_dc.gifhttp://geophysics.ou.edu/impacts/tunguska_dc.gif
Evidence for extraterrestrial impact
• No large meteorite fragments were found• Found were microscopic glass spheres that
contained high proportions of nickel and iridiumcontained high proportions of nickel and iridium
Evidence for extraterrestrial impact
No large meteorite fragments were foundFound were microscopic glass spheres that contained high proportions of nickel and iridiumcontained high proportions of nickel and iridium
Other ideas
• http://en.wikipedia.org/wiki/Tunguska_event
Other ideas
http://en.wikipedia.org/wiki/Tunguska_event
Craters• Tend to be round unless it is an oblique impact
Tycho crater
http://en.wikipedia.org/wiki/Impact_crater
Tycho crater on Moon
CratersTend to be round unless it is an oblique impact
Diameter 85 kmDepth 4.8 km
http://en.wikipedia.org/wiki/Impact_crater
Depth 4.8 km
Moon
(180 x 65 km).
http://www.boulder.swri.edu/~bottke/Oblique_craters/oblique.html
Mars
(380 x 140 km)
http://www.boulder.swri.edu/~bottke/Oblique_craters/oblique.html
CratersCraters
• Complex craters tend to be larger than simple cratersComplex craters tend to be larger than simple
• Complex Craters – gravity causes the steep crater walls to collapse, which
makes complex craters very shallowmakes complex craters very shallow– Central uplift where the earth rebounds from the
impact
gravity causes the steep crater walls to collapse, which makes complex craters very shallowmakes complex craters very shallowCentral uplift where the earth rebounds from the
Complex
(Melosh, 1989)
Peak RingCentral peak Collapses
(Melosh, 1989)
Different types of craters
• http://www.classzone.com/books/earth_science/terc/content/investigations/es2506/es2506page07.cfmm
Different types of craters
http://www.classzone.com/books/earth_science/terc/content/investigations/es2506/es2506page07.cf
• Small craters are usually much more common than larger ones
http://mars.jpl.nasa.gov/gallery/craters/hires/Gusev(plain).jpg
Small craters are usually much more common
http://mars.jpl.nasa.gov/gallery/craters/hires/Gusev(plain).jpg
• More craters at smaller sizes More craters at smaller sizes - older
Dating through crater counting(Things to bear in mind)
• Impact rate and size distribution of impacting bodies
• Temporal and spatial variations in impactor population
• Temporal variation in the target• Crater degradation• Secondary impacts• Need for measured surface ages to calibrate
counting
Dating through crater counting(Things to bear in mind)
Impact rate and size distribution of impacting
Temporal and spatial variations in impactor
Temporal variation in the target
Need for measured surface ages to calibrate
Calibration
• Moon – we have samples from specific places• Other planets – no samples
Calibration
we have samples from specific placesno samples
http://www.psi.edu/projects/mgs/chron04c.htmlhttp://www.psi.edu/projects/mgs/chron04c.html
• Cratering rate will be different on Mars compared to the Moon– Mars has larger mass so larger flux (gravitational – Mars has larger mass so larger flux (gravitational
focusing)– Mars closer to asteroid belt (more possible impactors)
Cratering rate will be different on Mars compared
Mars has larger mass so larger flux (gravitational Mars has larger mass so larger flux (gravitational
Mars closer to asteroid belt (more possible impactors)
• http://apod.nasa.gov/apod/ap010218.html• The Moon's orbital period is 27.322 days • Rotation period and orbital period are the same• Rotation period and orbital period are the same• This means we keep on seeing the same side of
the Moon
http://apod.nasa.gov/apod/ap010218.htmlThe Moon's orbital period is 27.322 days Rotation period and orbital period are the sameRotation period and orbital period are the sameThis means we keep on seeing the same side of
Moon
• The Moon is the only know natural satellite of Earth.
• Compared with the satellites of other planets of the solar system, The Moon is a large moon with a diameter of system, The Moon is a large moon with a diameter of 3476 km and a mass of 7.349 x 10
• The Moon is an average distance of 384,400 km from Earth and completes its revolution of Earth in 27.32 days.
Moon
The Moon is the only know natural satellite of Earth.
Compared with the satellites of other planets of the solar system, The Moon is a large moon with a diameter of system, The Moon is a large moon with a diameter of 3476 km and a mass of 7.349 x 1022 kg.
The Moon is an average distance of 384,400 km from Earth and completes its revolution of Earth in 27.32 days.
• The Earth's magnetic field strength is about 100 times higher than the highest value measured on the Moon by the Apollo missions
• The Moon does not have a magnetic field like the Earth (North and South Poles) due most likely to having a solid (or only partially molten) core
• Earth’s core is convecting• A flowing molten iron-nickel
http://geomag.usgs.gov/images/faq/Q6.jpg
• A flowing molten iron-nickel material can produce electrical current, which, in turn produces a magnetic field that surrounds the Earth
The Earth's magnetic field strength is about 100 times higher than the highest value measured on the Moon by the Apollo missionsThe Moon does not have a magnetic field like the Earth (North and South Poles) due most likely to having a solid (or only partially molten) core
nickel
http://geomag.usgs.gov/images/faq/Q6.jpgEarth
nickel material can produce electrical current, which, in turn produces a magnetic field that surrounds the
• The first manmade object to land on the Moon was Luna 2 in 1959
• The first photographs of the far side of the Moon • The first photographs of the far side of the Moon were made by Luna 3 that same year
The first manmade object to land on the Moon
The first photographs of the far side of the Moon The first photographs of the far side of the Moon were made by Luna 3 that same year
Who proposed an American mission to the Moon in 1962?
Who proposed an American mission to the Moon in 1962?
Houston, TexasSeptember 12, 1962
• We choose to go to the Moon. We choose to go to the moon in this decade and do the other things, not only because they are easy, but because they are hard, because that goal will because they are hard, because that goal will serve to organize and measure the best of our energies and skills, because that challenge is one that we are willing to accept, one we are unwilling to postpone, and one which we intend to win, and the others, too.
Houston, TexasSeptember 12, 1962
We choose to go to the Moon. We choose to go to the moon in this decade and do the other things, not only because they are easy, but because they are hard, because that goal will because they are hard, because that goal will serve to organize and measure the best of our energies and skills, because that challenge is one that we are willing to accept, one we are unwilling to postpone, and one which we intend to win, and the others, too.
• The first people to land on the Moon came aboard Apollo 11 in 1969.The first people to land on the Moon came aboard
Regolith – Lunar soilNo moisture or organic component compared to terrestrial soilNo moisture or organic component compared to terrestrial soil
Who was the 1st person to walk on the Moonperson to walk on the Moon
Who was the 1st person to walk on the Moon
• Neil Armstrong• Apollo 11
person to walk on the Moon
Who was the 2nd person to walk on the Moon
Who was the 2nd person to walk on the Moon
Who was the 2nd person to walk on the Moon
• Buzz Aldrin• Apollo 11
Who was the 2nd person to walk on the Moon
Moon
• 30,000 craters having a diameter of at least 1 kilometers
• Large craters are named after famous deceased • Large craters are named after famous deceased scientists, scholars, artists
Moon
30,000 craters having a diameter of at least 1
Large craters are named after famous deceased Large craters are named after famous deceased scientists, scholars, artists
• The largest crater on the Moon, and indeed the largest known crater within the solar system, forms the South Pole-Aitken basin.forms the South Pole-Aitken basin.
• Roughly 2,500 kilometers in diameter and 13 kilometers deep
The largest crater on the Moon, and indeed the largest known crater within the solar system,
Aitken basin.Aitken basin.Roughly 2,500 kilometers in diameter and 13
Central part of South Pole
http://www.nhk.or.jp/kaguya/archive/index_e.html
Central part of South Pole-Aitken Basin
http://www.nhk.or.jp/kaguya/archive/index_e.html
• The dark and relatively featureless lunar plains are called maria, Latin for seas, since they were believed by ancient astronomers to be water-filled seas.
• They are actually vast ancient basaltic lava flows that filled the basins of large impact craters.
• Maria are found almost exclusively on the Lunar nearside, with the Lunar farside nearside, with the Lunar farside having only a few scattered patches.
The dark and relatively featureless lunar plains are called maria, Latin for seas, since they were believed by ancient
filled seas. They are actually vast ancient basaltic lava flows that filled the basins of large impact craters. Maria are found almost exclusively on the Lunar nearside, with the Lunar farside nearside, with the Lunar farside having only a few scattered patches.
Far Side of MoonFar Side of Moon
Other features on Moon• Rille - long, narrow depressions in the lunar
surface that resemble channels.• Floor of Gassendi crater• Leading theories for rille
formation include collapsed lava
http://en.wikipedia.org/wiki/Image:AS16
formation include collapsed lava tubes and tectonic extension.
Other features on Moonlong, narrow depressions in the lunar
surface that resemble channels.
formation include collapsed lava
http://en.wikipedia.org/wiki/Image:AS16-120-19295.jpg
formation include collapsed lava tubes and tectonic extension.
Other features on Moon• Scarp – steep slope or cliff• The Altai Scarp, which is
the rim of the 860 km wide Nectaris impact basin, is nearly 500 km long and nearly 500 km long and 3 to 4 km high.
Other features on Moon
The Altai Scarp, which is the rim of the 860 km wide Nectaris impact basin, is nearly 500 km long and nearly 500 km long and
http://www.lpod.org/?m=20060517
Stratigraphy
• Stratigraphy – studies rock layers and layering• On planetary bodies, we tryi to determine the
relative ages when things formedrelative ages when things formed
Stratigraphy
studies rock layers and layeringOn planetary bodies, we tryi to determine the relative ages when things formedrelative ages when things formed
Principle of Superposition
http://earthsci.org/fossils/geotime/time/Super.gif
Principle of Superposition
http://earthsci.org/fossils/geotime/time/Super.gif
http://dept.kent.edu/geology/ehlab/fundamentals/cross_cut.gifhttp://dept.kent.edu/geology/ehlab/fundamentals/cross_cut.gif
Crater Rays
• Historically, they were once regarded as salt deposits from evaporated water (early 1900s) and volcanic ash or dust streaks (late 1940s).volcanic ash or dust streaks (late 1940s).
• Now rays are recognized as fragmental material ejected from primary and secondary craters during impact events
Crater Rays
Historically, they were once regarded as salt deposits from evaporated water (early 1900s) and volcanic ash or dust streaks (late 1940s).volcanic ash or dust streaks (late 1940s).Now rays are recognized as fragmental material ejected from primary and secondary craters during
Crater Rays• In laboratory sand-layer vertical impacts, the ejecta does
come out evenly around the crater.• But in a real impact, there are a number of complicating
factors.• There can be variations in the strength (from pre
fractures in the surface, or inhomogeneties in the target rock) that lead to "jetting" of ejecta and presumably the rock) that lead to "jetting" of ejecta and presumably the rays.
http://en.wikipedia.org/wiki/Image:AS11
Crater Rayslayer vertical impacts, the ejecta does
come out evenly around the crater.But in a real impact, there are a number of complicating
There can be variations in the strength (from pre-existing fractures in the surface, or inhomogeneties in the target rock) that lead to "jetting" of ejecta and presumably the rock) that lead to "jetting" of ejecta and presumably the
http://en.wikipedia.org/wiki/Image:AS11-42-6285.jpg
Copernicus93 km wide
http://apod.nasa.gov/apod/image/0503/moon8_mandel.jpghttp://apod.nasa.gov/apod/image/0503/moon8_mandel.jpg
Tycho85 km wide
• Only 2.5% of the surface of the far side is covered by mare, compared to 31.2% on the near side.
• The likely explanation is that the far side crust is • The likely explanation is that the far side crust is thicker, making it harder for molten material from the interior to flow to the surface and form the smooth maria.
Only 2.5% of the surface of the far side is covered by mare, compared to 31.2% on the near side. The likely explanation is that the far side crust is The likely explanation is that the far side crust is thicker, making it harder for molten material from the interior to flow to the surface and form the
Why do we always see the same side of the Moon?
• Tidal locking of the Moon's rotation to its orbit (the phenomenon whereby the Moon spins on its axis in the same timespan as it takes to orbit the axis in the same timespan as it takes to orbit the Earth).
Why do we always see the same side of the Moon?
Tidal locking of the Moon's rotation to its orbit (the phenomenon whereby the Moon spins on its axis in the same timespan as it takes to orbit the axis in the same timespan as it takes to orbit the
• The lighter-colored areas are called the highlandscolored areas are called the highlands
• Luna 2 - impact on the surface of the Moon (1959) (USSR)• Luna 3 - first photos of the far side of the Moon (1959)
(USSR)• Apollo - Six manned landings on the Moon with sample
return 1969-72. – (The seventh landing, Apollo 18, was canceled for
political reasons)• Luna 16 - automated sample return from the Moon (1970) • Luna 16 - automated sample return from the Moon (1970)
(USSR) • Clementine - a joint mission of the Ballistic Missile Defense
Organization and NASA (1994)• Lunar Prospector - the first NASA mission to the Moon in
almost 30 years (1998-1999)• SMART-1 - The European Space Agency’s (ESA) spacecraft
orbited the Moon and then crashed into the Moon in (September, 2006)
impact on the surface of the Moon (1959) (USSR)first photos of the far side of the Moon (1959)
Six manned landings on the Moon with sample
(The seventh landing, Apollo 18, was canceled for
automated sample return from the Moon (1970) automated sample return from the Moon (1970)
a joint mission of the Ballistic Missile Defense Organization and NASA (1994)
the first NASA mission to the Moon in
The European Space Agency’s (ESA) spacecraft orbited the Moon and then crashed into the Moon in
Currently• Japanese SELENE mission (also known as Kaguya) orbited the
Moon from 2007-2009• Goal was "to obtain scientific data
and to develop the technology for the future lunar exploration"
http://www.selene.jaxa.jp/en/about/image/img_equipment_001_e.jpg
CurrentlyJapanese SELENE mission (also known as Kaguya) orbited the
c data of the lunar origin and evolution and to develop the technology for the future lunar exploration"
http://www.selene.jaxa.jp/en/about/image/img_equipment_001_e.jpg
Pythagoras Crater from SMART
http://www.space.com/imageoftheday/image_of_day_060626.htmlhttp://cdn2.libsyn.com/astronomy/moon_show20
Pythagoras Crater from SMART-1
http://www.space.com/imageoftheday/image_of_day_060626.htmlw20.gif?nvb=20081110153501&nva=20081111153501&t=0b619a8f8100c5f7820f5
Pythagoras Crater from Selene
Diameter 130 km, Depth 5.0 km
http://wms.selene.jaxa.jp/data/en/hdtv/006/hdtv_006_3/hdtv_006_3_l.jpg
Pythagoras Crater from Selene
Diameter 130 km, Depth 5.0 km
http://wms.selene.jaxa.jp/data/en/hdtv/006/hdtv_006_3/hdtv_006_3_l.jpg
• http://space.jaxa.jp/movie/20080411_kaguya_movie01_e.htmlhttp://space.jaxa.jp/movie/20080411_kaguya_mo
Currently
• India's national space agency launched Chandrayaanan unmanned lunar orbiter, on October 22, 2008.
• Estimated cost was $80 million • Its scientific objectives was to prepare a three• Its scientific objectives was to prepare a three
dimensional atlas of the near and far side of the moon and to conduct a chemical and mineralogical mapping of the lunar surface.
• Mission ended on August 29, 2009
Currently
India's national space agency launched Chandrayaan-1, an unmanned lunar orbiter, on October 22, 2008.Estimated cost was $80 million Its scientific objectives was to prepare a three-Its scientific objectives was to prepare a three-dimensional atlas of the near and far side of the moon and to conduct a chemical and mineralogical mapping
Mission ended on August 29, 2009
Chandrayaan
http://en.wikipedia.org/wiki/Image:Chandrayaan_1.jpg
Chandrayaan-1
http://en.wikipedia.org/wiki/Image:Chandrayaan_1.jpg
Water on MoonWater on Moon
How much water?
• The Moon’s surface holds as much as a liter of water in every metric ton (1,000 kg) of lunar soil
How much water?
The Moon’s surface holds as much as a liter of water in every metric ton (1,000 kg) of lunar soil
• A total of 382 kg of rock samples were returned to the Earth by the Apollo and Luna programs.
• Apollo - 381.69 kg • Apollo - 381.69 kg • Luna – 300 g
http://nssdc.gsfc.nasa.gov/database/MasterCatalog?sc=1970
Luna 16
A total of 382 kg of rock samples were returned to the Earth by the Apollo and Luna programs.
Apollo 16
http://nssdc.gsfc.nasa.gov/database/MasterCatalog?sc=1970-072A
http://en.wikipedia.org/wiki/Image:Apollo_16_LM.jpg
Apollo 16
http://en.wikipedia.org/wiki/Image:Apollo_15_Genesis_Rock.jpg
Apollo 15 sample“Genesis Rock”Very ancient sample4 billion years old
http://en.wikipedia.org/wiki/Image:Apollo_15_Genesis_Rock.jpg
Did We Land on the Moon
• http://www.youtube.com/watre=related
Did We Land on the Moon
m/watch?v=LHzufIymeEE&featu
Rocks and More MoonRocks and More Moon
• Mineral – A naturally occurring, homogeneous inorganic solid substance having a definite chemical composition and characteristic crystal chemical composition and characteristic crystal structure
• Rock - naturally occurring aggregate of minerals
A naturally occurring, homogeneous inorganic solid substance having a definite chemical composition and characteristic crystal chemical composition and characteristic crystal
naturally occurring aggregate of minerals
Forming Different Mineralogies
• Can be on a planet-scale• Or a few meters to kilometers
Forming Different Mineralogies
scaleOr a few meters to kilometers
http://www.gly.fsu.edu/~salters/GLY1000/8Igneous_rocks/Slide16.jpg
Some minerals form
http://www.gly.fsu.edu/~salters/GLY1000/8Igneous_rocks/Slide16.jpg
Some minerals formbefore other minerals
What minerals form?
• Depends on the composition of the magma• Depends how quickly the magma cools
What minerals form?
Depends on the composition of the magmaDepends how quickly the magma cools
Types of Rocks
• Igneous – rock that solidified from molten or partially molten material
• Metamorphic - rock that has changed in composition, mineral content, texture, or structure
• Metamorphic - rock that has changed in composition, mineral content, texture, or structure by the application of heat or pressure
• Sedimentary – rock formed from material that was deposited as sediment by water, wind, or ice and then compressed and cemented
Types of Rocks
rock that solidified from molten or partially molten material
rock that has changed in composition, mineral content, texture, or structure
rock that has changed in composition, mineral content, texture, or structure by the application of heat or pressure
rock formed from material that was deposited as sediment by water, wind, or ice and then compressed and cemented
Igneous Rock
http://en.wikipedia.org/wiki/Image:Magma.jpg
Igneous Rock
http://en.wikipedia.org/wiki/Image:Magma.jpg
Metamorphism
http://en.wikipedia.org/wiki/Image:Quartzite.jpg
Metamorphism
Quartzite
http://en.wikipedia.org/wiki/Image:Quartzite.jpg
Sedimentary• Examples of two types of sedimentary rock: limey
shale overlaid by limestone
http://en.wikipedia.org/wiki/Image:Limestoneshale7342.jpg
SedimentaryExamples of two types of sedimentary rock: limey shale overlaid by limestone
http://en.wikipedia.org/wiki/Image:Limestoneshale7342.jpg
• Rock formed from sediments covers 75the Earth's land area Rock formed from sediments covers 75-80% of
Lunar Meteorites
• 44 known as of today• only 1 in 1200 meteorites are lunar• Lunar meteorites go for $800 and $40,000 per • Lunar meteorites go for $800 and $40,000 per
gram. By comparison, the price of 24is about $20 per gram and gemstart at $1000-2000/gram.
http://epsc.wustl.edu/admin/resources/moon_meteorites.html
Lunar Meteorites
only 1 in 1200 meteorites are lunarLunar meteorites go for $800 and $40,000 per Lunar meteorites go for $800 and $40,000 per gram. By comparison, the price of 24-carat gold is about $20 per gram and gem-quality diamonds
2000/gram.
http://epsc.wustl.edu/admin/resources/moon_meteorites.html
Mare
http://epsc.wustl.edu/admin/resources/moon/howdoweknow.htmlhttp://en.wikipedia.org/wiki/Image:Lunar_Ferroan_Anorthosite_60025.jpg
Lunar Highlands
http://epsc.wustl.edu/admin/resources/moon/howdoweknow.htmlhttp://en.wikipedia.org/wiki/Image:Lunar_Ferroan_Anorthosite_60025.jpg
• Highlands – contain Al-rich material– Plagioclase feldspar - CaAl
• Mare – contain Fe-rich material • Mare – contain Fe-rich material – Olivine - (Mg, Fe)2SiO4
– Pyroxene – (Mg,Fe)SiO3
– Ilmenite - FeTiO3
rich materialCaAl2Si2O8
rich material – basaltic eruptionsrich material – basaltic eruptions
Fe-rich
http://epsc.wustl.edu/admin/resources/moon_meteorites.htmlhttp://epsc.wustl.edu/admin/resources/moon_meteorites.html
Al-rich
Magma OceanMagma Ocean
How do you form the Moon?How do you form the Moon?
Definitions
• Volatile – evaporates easily• Refractory – does not evaporate easily
Definitions
evaporates easilydoes not evaporate easily
Need to account for these things
• The Moon's low density (3.3 g/cc) shows that it does not have a substantial iron core like the Earth does.
• Moon rocks contain few volatile substances (e.g. water), which implies extra baking of the lunar surface relative to that of Earth.
• The relative abundance of oxygen isotopes on Earth and on the Moon are identical, which suggests that the Earth and Moon formed at the same distance from the Sun.
Need to account for these things
The Moon's low density (3.3 g/cc) shows that it does not have a substantial iron core like the Earth does.Moon rocks contain few volatile substances (e.g. water), which implies extra baking of the lunar surface relative to
The relative abundance of oxygen isotopes on Earth and on the Moon are identical, which suggests that the Earth and Moon formed at the same distance from the Sun.
Oxygen Isotopes• There are three stable isotopes of oxygen• They have masses of 16, 17, and 18 atomic mass units
%
• 16O ~99.762• 17O ~0.038 • 18O ~0.200• The oxygen isotopic ratios (
silicate rocks from the Earth and Moon are the same and are different from most meteorites and Mars
Oxygen Isotopeshere are three stable isotopes of oxygen
They have masses of 16, 17, and 18 atomic mass units
The oxygen isotopic ratios (17O/16O and 18O/16O of silicate rocks from the Earth and Moon are the same and are different from most meteorites and Mars
http://www4.nau.edu/meteorite/Meteorite/Images/MeteoriteOxygen9.jpghttp://www4.nau.edu/meteorite/Meteorite/Images/MeteoriteOxygen9.jpg
Atmosphere
• Not much of an atmosphere since the Moon’s gravity is so small
Atmosphere
Not much of an atmosphere since the Moon’s gravity is
Any Questions?Any Questions?Any Questions?Any Questions?