astronomy 101 the solar system tuesday, wednesday, thursday tom burbine tomburbine@astro.umass

Astronomy 101The Solar System

Tuesday, Wednesday, Thursday

Tom Burbinetomburbine@astro.umass.edu

Remaining Schedule

• Today – Quiz; Meteorites, Mercury, and Venus

• Wednesday - Presentations

• Thursday - Mars

• Tuesday – Last quiz; Optional final; Final presentation

What are meteorites?

Meteorite

• A small extraterrestrial body that reaches the Earth's surface

Why are meteorites important?

Why are meteorites important?

• They are primarily fragments of asteroids, which can hit us

• They are records of the early solar system

Moon

Meteorites

• Usually have ages of ~4.6 billion years

• Asteroids and comets are thought to be the building blocks of the terrestrial planets

Meteorites

• Many early cultures recognized (or believed) certain stones as having fallen from the sky

• Many early cultures had tools made from iron meteorites

• But to the scientists of the Renaissance and later periods, stones falling from the heavens were considered superstition or heresy

More evidence …

• In 1492, a meteorite weighing almost 130 kilograms landed near the town of Ensisheim, Alsace, France, then in the hands of Germany

Then ..

• In 1794, Ernst Friedrich Chladni, considered the father of meteoritics, published a book in which he concluded that stone and iron masses did fall out of the sky

• In 1803, thousands of meteorite fragments bombarded L'Aigle in Normandy, France, an event investigated by Jean-Baptiste Biot of the French Academy of Science.

Thomas Jefferson

• Meteorite landed in Weston, CT

• It was brought to Yale where it was concluded it was from outer space

• Thomas Jefferson, President of the United states, was told about it

And responded

• "Gentlemen, I would rather believe that two Yankee professors would lie than believe that stones fall from heaven."

Meteorites

• Named after a nearby geographic locality

Meteorite

• Esquel Pallasite

• Found in Esquel, Argentina

Meteorites

• Almost all are thought to be fragments of asteroids

• Where else can they come from?

Meteorites

• Almost all are thought to be fragments of asteroids• Where else can they come from?

– Moon - ~68 samples– Mars - ~34 samples– Comets?– Venus?– Mercury?– Other solar systems?

Peekskill Meteorite

• http://aquarid.physics.uwo.ca/~pbrown/Videos/peekskill.htm

Meteorites

• Meteorites are composed of different minerals– Silicates – contain silicon and oxygen– Sulfides – contain sulfur– Oxide – contains oxygen– Iron-nickel metal

Meteorites

• Usually named after the town (or nearest town) where they fell or were located

Falls and Finds

• Falls – see them fall

• Finds – find them

Fall Statistics (greater than 1%)• Meteorite type Fall Percentages

• L chondrites 38.0%

• H chondrites 34.1%

• LL chondrites 7.9%

• Irons 4.2%

• Eucrites 2.7%

• Howardites 2.1%

• CM 1.7%

• Diogenites 1.2%

• Aubrites 1.0%

Where is the best place to find meteorites on Earth?

Where is the best place to find meteorites on Earth?

• Antarctica• Deserts

– Sahara

Antarctic Meteorites• Designation for which ice field

they were found• ALH Allan Hills

EET Elephant MoraineLEW Lewis Cliff

• Then year and then number (which gives order of discovery)

• For example, ALH 84001 was first meteorite discovered in 1984-1985 field season

How do you know a rock is a meteorite?• Some possible indicators• Presence of Iron-Nickel (FeNi) Metal• Density• Magnetism• Presence of Chondrules• Fusion Crust• Regmaglypts

– Ablation of meteoritewhile passing throughatmosphere

Meteor-wrongs

• For example, magnetite (Fe3O4) is magnetic, but has grey streak

• The best test is finding

Ni in the metallic iron

• NWA 736 (H3.7) NWA stands for North West Africa• Hassayampa (H4)• Pultusk (H5)• NWA 869 (L5)• Holbrook (L6)• Long Island (L6)• NWA 2040 (LL3.5)• NWA 1584 (LL5)• NWA 852 (CR2)• NWA 2086 (CV3)• NWA 800 (R4)• NWA 1929 (Howardite)• NWA 3140 (Ureilite)• Canyon Diablo (iron)• Nantan (Iron)• Sikhote-Alin (Iron)

• Acapulcoites• Angrites• Ataxites• Aubrites• Brachinites• CB• CH• CI• CK• CM• CO• CR• CV• Diogenites

• EH• EL • Eucrites• H• Hexahedrites • Howardites• L• LL• Lodranites• Mesosiderites• Octahedrites• Pallasites• R• Ureilites• Winonaites

Basic types

• Stony – primarily silicates (but can have some FeNi)

• Stony-Iron – ~50-50 mixture of silicates and FeNi

• Iron –almost all FeNi

(Silicates are minerals containing Silicon, and usually Oxygen.)

Types of Stony Meteorites

• Chondrites – Heated but have not melted– Tend to contain chondrules– Aggregates of high- and low-temperature components

• Achondrites – Heating to the point of melting– Tend to differentiate

• Where material segregates due to density

• Chondritic body

• Differentiated body

Ordinary Chondrites

• Most common type of meteorite to fall to Earth

• Ordinary Chondrites – primarily olivine, pyroxene, and metal– H – high-iron – 34% of falls– L – low-iron – 38% of falls– LL – very low-iron – 8% of falls

Ordinary Chondrites

• H chondrites– ~30% olivine, ~30% pyroxene, ~20% FeNi

– Fa17-Fa20 Fs15-Fs17

• L chondrites – ~40% olivine, ~30% pyroxene, ~10% FeNi

– Fa23-Fa26 Fs19-Fs21

• LL chondrites– ~50% olivine, ~25% pyroxene, ~5% FeNi

– Fa27-Fa31 Fs22-Fs25

Within each ordinary chondrite group

• Type 3 are the most primitive (least heated)

• Type 4 has been heated to higher temperatures

• Type 5 heated to higher temperatures than type 4

• Type 6 heated to higher temperatures than type 5

• Pictures

Carbonaceous Chondrites

• Meteorites that contains high levels of water and organic compounds

• Water is in hydrated silicates

• Have not undergone significant heating (>200°C) since they formed

Carbonaceous Chondrites• CI1 I is for Ivuna

• CM2 M is for Mighei

• CR2 R is for Renazzo

• CH2 H is for High-Metal

• CB3 B is for Bencubbin

• CO3 O is for Ornans

• CV3 V is for Vigarano

• CK 3 K is for Karoonda– Could be CK4 or CK5

Alteration Sequence

• 3 is most primitive

• 2 has been aqueously altered

• 1 has been aqueously altered more than 2

CI1 chondrite

• Ivuna – up to 20 wt.% water

CI chondrites haveelemental compositionssimilar to the Sun

CM2 chondrite

• Murchison

CV3 chondrite

• Allende

• Fell February 8, 1969

• Over 2,000 kilograms of material

was recovered

CV3 chondrite

• Contain chondrules

• And Calcium Aluminum Inclusions (CAIs)– They consist of high-temperature minerals, including

silicates and oxides containing calcium, aluminum, and titanium.

– Some CAIs were dated at 4.57 billion years, making them the oldest known objects in the solar system

Difference

• Chondrules are round and composed mostly of silicate minerals like olivine and pyroxene

• CAIs are predominantly white to light gray in color and irregularly shaped and rich in refractory minerals like melilite and spinel

• Melilite - (Ca,Na)2(Al,Mg)(Si,Al)2O7

• Spinel - MgAl2O4

Other types of chondrites

• Enstatite Chondrites (EH and EL) – primarily

enstatite (Magnesium silicate)

• R chondrites –primarily olivine, no FeNi

tiny crystalline grains found in the fine-grained matrix of primitive

meteorites, and are assumed to be older than the solar system.

Achondrites

• Stony meteorites that were heated to the point of melting– HEDs – basaltic crust (lava flows)– Eucrites - pigeonite and plagioclase– Howardites - mixtures of eucrite and diogenite

material– Diogenites - orthopyroxene

• HEDs are thought to be fragments of asteroid 4 Vesta

Differentiation

• Meteorites from the same parent body can

have a very different composition if they

are from a parent body that has differentiated

• Basaltic crust

• Olivine Mantle

• FeNi core

Eucrites

• Basalts• Contain pigeonite and

plagioclase

Diogenites

• mainly magnesium-rich orthopyroxene

• Minor plagioclase• Sometimes olivine

Howardites

• Mixture of eucritic and diogenitic material

Aubrites

• Enstatite-rich achondrite

Angrites

– contain predominately anorthite, Al-Ti diopside-hedenbergite, and Ca-rich olivine

Irons• FeNi

• Some show the growth of two FeNi minerals with different crystal structures

• Widmanstätten pattern – shows when etched with weak acid

• Kamacite – light – Ni-poor

• Taenite – dark – Ni-rich

• Most thought to be cores of

differentiated bodies

Widmanstätten pattern

• Widmanstätten patterns are composed of interleaving kamacite and taenite bands (or ribbons) called lamellae.

• Kamacite - metallic iron with up to 7.5% nickel

• Taenite - iron with 20-65% nickel

Irons

• Ataxite – made almost entirely of taenite (more than 16% Ni)

• Octahedrite – composed of both taenite and kamacite (6-16% Ni)

• Hexahedrite - composed almost entirely of kamacite (less than 6% Ni)

Ataxite

• Made almost entirely of taenite

Octahedrite

• Have Widmanstätten pattern

• Plessite are the spaces between larger kamacite and taenite plates are often filled by a fine-grained mixture of kamacite and taenite

Hexahedrite

• Often have fine parallel line called Neumann lines

• Shock-induced, structural deformation of the kamacite

Stony-Irons

• Pallasites

• Mesosiderites

Pallasite

• Olivine and FeNi

Mesosiderite

• Mixture of silicates and metallic iron

• Silicate material is similar to that found in HEDs

Primitive Achondrites

• Experienced a limited amount of melting so they have bulk compositions and mineralogies similar to chondritic meteorites– Acapulcoites – olivine, pyroxene, FeNi– Lodranites – olivine, pyroxene, FeNi– Winonaites - olivine, pyroxene, FeNi

How old is the solar system?

How old is the solar system?

• ~4.6 billion years

• All meteorites tend to have these ages

• Except:

How old is the solar system?

• ~4.6 billion years

• All meteorites tend to have these ages

• Except:– Martian meteorites– Lunar meteorites

Ages

• Ages

How do you determine this age?

Dating a planetary surface

• Radioactive Dating – Need sample

• Crater counting – Need image of surface

Radioactivity

• The spontaneous emission of radiation (light and/or particles) from the nucleus of an atom

Radioactivity

http://wps.prenhall.com/wps/media/tmp/labeling/2130796_dyn.jpg

Half-Life

• The time required for half of a given sample of a radioactive isotope (parent) to decay to its daughter isotope.

Radioactive Dating• You are dating when a rock crystallized

http://faculty.weber.edu/bdattilo/images/tim_rock.gif

Radioactive Dating n = no(1/2)(t/half-life)

no = original amount

n = amount left after decay

Also can write the formula as

n = noe-λt

λ is the decay constant

decay constant is the fraction of a number of atoms of a radioactive nuclide that disintegrates in a unit of time

Half life = (ln 2)/λ = 0.693/λ

• where e = 2.718 281 828 459 045 …

• Limit (1 + 1/n)n = e

n→∞

• For example if you have n = 1,000

• The limit would be 2.716924

http://www.gpc.edu/~pgore/myart/radgraph.gif

Exponential decay is where the rate of decay is directly proportional to the amount present.

• x = by

• y = logb(x)

• For example,• 100 = 102

• 2 = log10(100)

• 0.01 = 10-2

• -2 = log10(0.01)

• 2 = e0.693

• 0.693 = lne2

Remember

• Number of original atoms (parent atoms)

• = number of daughter atoms today + number of parent atoms today

http://academic.brooklyn.cuny.edu/geology/leveson/core/topics/time/graphics/radio1.gif

What are the assumptions to get an age?

What are the assumptions?

• No loss of parent atoms– Loss will increase the apparent age of the sample.

• No loss of daughter atoms– Loss will decrease the apparent age of the sample.

• No addition of daughter atoms or if daughter atoms was present when the sample formed– If there was, the age of the sample will be inflated

• These can possibly be all corrected for

Basic Formula

• Number of daughter atoms formed = number of parent atoms consumed

• If there were daughter atoms originally there

• D – Do = no - n

• Remember: n = noe-λt so no = n eλt

• D- Do = n eλt – n

• D = Do + n (eλt – 1)

Commonly Used Long-Lived Isotopes in Geochronology

Radioactive Parent (P)

Radiogenic Daughter

(D)

Stable Reference

(S)

Half-life, t½

(109 y) 

Decay constant, l

(y-1)

40K 40Ar  36Ar 1.25 0.58x10-10

87Rb 87Sr 86Sr 48.8 1.42x10-11

147Sm 143Nd 144Nd 106 6.54x10-12

232Th 208Pb 204Pb 14.01 4.95x10-11

235U 207Pb 204Pb 0.704 9.85x10-10

238U 206Pb 204Pb 4.468 1.55x10-10

How do you determine isotopic values?

How do you determine isotopic values?

• Mass Spectrometer

It is easier

• To determine ratios of isotopic values than actual abundances

Example

• 87Rb 87Sr + electron + antineutrino + energy

• Half-life is 48.8 billion years

• 87Sr = 87Srinitial + 87Rb (eλt – 1)

• Divide by stable isotope

• 87Sr = 87Srinitial + 87Rb (eλt – 1)

86Sr 86Sr 86Sr

Example

• Formula for line

• 87Sr = 87Srinitial + (eλt – 1) 87Rb

86Sr 86Sr 86Sr

y = b + m x

http://www.asa3.org/aSA/resources/wiens2002_images/wiensFig4.gif

= (eλt – 1)

Carbon-14

• 99% of the carbon is Carbon-12

• 1% is Carbon-13

• 0.0000000001% is Carbon-14

• The half-life of carbon-14 is 5730±40 years.

• It decays into nitrogen-14 through beta-decay (electron and an anti-neutrino are emitted).

• Due to Carbon-14’s short half-life, can only date objects up to 60,000 years old

• Plants take up atmospheric carbon through photosynthesis

http://hyperphysics.phy-astr.gsu.edu/hbase/nuclear/cardat.html

• When something dies, it stops being equilibrium with the atmosphere

http://hyperphysics.phy-astr.gsu.edu/hbase/nuclear/cardat.html

Why is Carbon-14 still present if it has such a short half-life?

Why is Carbon-14 still present if it has such a short half-life?

• Cosmic rays impact Nitrogen-14 and create Carbon-14

• Cosmic rays are energetic particles (90% are protons) originating from space. From the Sun (solar cosmic rays) or outside the solar system (galactic cosmic rays)

• n + 14N → 14C + p

• http://en.wikipedia.org/wiki/Image:Radiocarbon_bomb_spike.svg

What heats the asteroids?

Radioactive Heating

• Generally thought to be due to 26Al

• 26Al 26Mg + electron + energy

• Half-life of only 700,000 years

• Releases lots of energy

• If 0.005% of all the aluminum in a chondrite was 26Al, (most is aluminum-27, which is not radioactive), it would release enough energy to melt asteroids a few kilometers across and larger

Types of Planetary Missions

• Fly By

• Orbiter

• Lander– Atmospheric Probe– Rover– Manned

• Sample Return

Mercury/Venus

• Mercury is the closest planet to the Sun

• Venus is next closest

Mercury

• orbit: 0.38 AU from Sun• diameter: 4,880 km (38.3% of Earth)• mass: 3.30 x 1023 kg (5.5% of Earth)• temperature:

90 K (minimum) 440 K (average)700 K (maximum)

• Satellites: Zero

Difficult to study Mercury

• Because of Mercury's proximity to the Sun– makes reaching it with spacecraft technically

challenging– Earth-based observations difficult.

Mercury

• Videos

• http://www.gecdsb.on.ca/d&g/astro/html/Mercury.html

Mariner 10

• The first spacecraft to approach Mercury was NASA's Mariner 10 (1974-1975).

Caloris Basin

Caloris Basin(Some of the hill are 1,800 meters tall)

Messenger dataMariner 10 data

Caloris Basin• A basin was defined by Hartmann and Kuiper (1962) as a

"large circular depression with distinctive concentric rings and radial lineaments."

• Others consider any crater larger than 200 kilometers a basin.

• The Caloris basin is 1,550 kilometers in diameter, and was probably caused by a projectile larger than 100 kilometers in size.

• The impact produced concentric mountain rings three kilometers high and sent ejecta 600 to 800 kilometers across the planet.

Moon

Weird TerrainThe weird terrain is almost opposite Caloris Basin. It consists of hills, ridges and grooves that cut across craters. The weird terrain my have been formed by shock waves that raced through the center of the planet and outward early in Mercury's history.

Mercury has high density

• Its density is 5.44 g/cm3 which is comparable to Earth's 5.52g/cm3 density.

• In an uncompressed state, Mercury's density is 5.5 g/cm3 where Earth's is only 4.0 g/cm3.

http://www.psrd.hawaii.edu/WebImg/MercuryCore.gif

Magnetic Field

• Despite its small size and slow 59-day-long rotation, Mercury has a significant, and apparently global, magnetic field.

• It is about 1.1% as strong as the Earth’s.

• Particularly strong tidal effects caused by the planet's high orbital eccentricity would serve to keep the core in the liquid state so it could have a dynamo

Messenger

• Mission to Mercury• Launched August 3, 2004• Flew by Mercury in 2008

and 2009• Will orbit Mercury in

2011

Messenger video• A set of five 11-band images was captured by MESSENGER just after

the spacecraft crossed the night/day line (the “terminator”), which are the highest-resolution color images ever obtained of Mercury’s surface.

• At the beginning of this movie, it is dawn in that region of Mercury, and the Sun is just off the horizon. The long shadows that are cast by crater walls exaggerate the ruggedness of the terrain and highlight variations in topography.

• Though Mercury’s true colors are subtle, the 11 color bands of MDIS were combined in a statistical method used to highlight differences in color units. Older, low-reflectance, and relatively blue material is encroached by younger, relatively red smooth plains. Several lobate scarps or cliffs are observed, which are places where compressional stresses caused Mercury’s crust to fracture and shorten.

http://messenger.jhuapl.edu/news_room/presscon5_images/Robinson%20Image%205.7.mov

Mercury

http://space.newscientist.com/data/images/ns/cms/dn14893/dn14893-1_450.jpg

Much of the image to the right of the Kuiper crater (in the centre here) had never been imaged by a spacecraft before. Researchers were surprised to see long crater rays that extend thousands of kilometers from a crater at the planet's north pole

Mercury

Dark material, shown in deep blue in the enhanced colour image at right (a composite of visible and near-infrared images), was kicked up by impacts. The material seems to be widespread but patchy, suggesting the planet's interior is not homogenous.

http://space.newscientist.com/data/images/ns/cms/dn15077/dn15077-1_600.jpg

Mercury• Double ringed basin

• 290 km in diameter

• Appears young (few craters on it)

• ~ 1 billion years old

• Lava may have covered up the central part of the basin

http://messenger.jhuapl.edu/gallery/sciencePhotos/pics/presscon6_img4_5_lg.jpg

• 160 km in diameter

http://en.wikipedia.org/wiki/File:Mercury_Double-Ring_Impact_Basin.png

Spectra of Mercury

Weak to absent absorption features – no iron in the silicates

Mercury’s Surface

• Possibly made of Enstatite (MgSiO3) – Mg-rich pyroxene

• Possibly made of material like the Lunar Highlands– Plagioclase feldspar - CaAl2Si2O8

Questions:

• Why does Mercury have such a large iron core?

One possibility

• Mercury may have been struck by a planetesimal of approximately 1/6 its mass and several hundred kilometers across.

• The impact would have stripped away much of the original crust and mantle, leaving the core behind as a relatively major component.

Venus

• orbit: 0.72 AU from Sun• diameter: 12,103.6 km (94.9% of Earth) (called Earth‘s twin)• mass: 4.869 x 1024 kg (81.5% of Earth)• Temperature on surface:

726 K(average)

• Satellites: Zero

Venus’ atmosphere• Atmospheric pressure at surface is 92 times the

pressure on the Earth’s surface

• Atmospheric content:

• Carbon dioxide 96.5 %

• Nitrogen 3.5 %

• Sulfur dioxide 150 ppm

• Argon 70 ppm

• Water vapor 20 ppm

Venus’ clouds

• Venusian clouds are thick and are composed of sulfur dioxide and droplets of sulfuric acid.

• These clouds reflect about 75% of the sunlight that falls on them,

Greenhouse Effect• The greenhouse effect is the rise in temperature

that a planet experiences because certain gases in the atmosphere (H2O, CO2, CH4) trap energy emitted from the surface.

• Visble light hits the surface• Surface warms and emits infrared radiation• Atmospheric gases absorb some of the infrared

light• Surface and Atmosphere heat up

Runaway Greenhouse Effect

• Runaway greenhouse effect to describe the effect as it occurs on Venus

• Venus is sufficiently strongly heated by the Sun that water is vaporized and so carbon dioxide is not reabsorbed by the planetary crust

Why does Venus has such a thick atmosphere?

• The luminosity of the Sun has increased by 25% from 3.8 billion years ago

• The atmosphere of Venus up to around 4 billion years ago maybe was more like that of Earth with liquid water on the surface.

• The runaway greenhouse effect may have been caused by the evaporation of the surface water and the rise of the levels of greenhouse gases that followed.

Surface

• Mapped by Magellan spacecraft (1990-1994)

• How was it mapped if it has a dense atmosphere?

How did it do it?

• Used Radar (radio waves)

• Most of Venus' surface consists of gently rolling plains with little relief.

• Data from Magellan's imaging radar shows that much of the surface of Venus is covered by lava flows.

• Lava flows stopped ~300-500 million years ago

• Very few craters

• Most volcanoes on Venus are shield volcanoes

• Low viscosity lava

Maat Mons

• Highest volcano on Venus

• 8 km high

• Shield Volcano

• Could be active

Volcanoes

• ~170 giant volcanoes over 100 km across

• On Earth, only the Big Island of Hawaii is this large

• This is due to Venus’ crust being older

• Earth’s crust is continually being recycled by subduction

Craters

• Venusian craters range from 3 km to 280 km in diameter.

• There are no craters smaller than 3 km because the dense atmosphere stops small incoming objects.

• 200 km long channel

• 2 km wide

http://hyperphysics.phy-astr.gsu.edu/hbase/Solar/venusurf.html

Pancakes Domes

• Flattened lava domes are attributed to upwellings of molten rock which then subsided.

• The solid crust left behind then flattened and cracked.

Coronae• Corona is an oval-shaped feature.

• hot rising bodies of magma reach the crust and cause it to partially melt and collapse

• Generates volcanic flows and fault

patterns that radiate from the

central structure.

http://pds.jpl.nasa.gov/planets/captions/venus/vencor.htm

100 km in diameter

Arachnoids

• concentric ovals surrounded by a complex network of fractures, and can span 200 kilometers

• Almost all Venusian surface features are named after historical and mythological women.

• The only exceptions are Maxwell Montes, named after James Clerk Maxwell, and two highland regions, Alpha Regio and Beta Regio

Venera

• Venera probes were launched by the Soviet Union and enter Venus’ atmosphere

• 1961-1984

• Venera 3-16

• 10 probes landed on surface

Venera 9

Venera 9 and 10 pictures

Venera 13

Venera 13

Venera 13

Pioneer

• Pioneer Venus 1 or Pioneer Venus Orbiter was launched in 1978 and studied the planet for more than a decade after orbital insertion in 1978.

• Pioneer Venus 2 or Pioneer Venus Multiprobe sent four small probes into the Venusian atmosphere.

Pioneer 2

Pioneer 2 bus• The Pioneer Venus bus portion of the spacecraft was targeted

to enter the Venusian atmosphere at a shallow entry angle and transmit data until destruction by the heat of atmospheric friction.

• The objective was to study the structure and composition of the atmosphere down to the surface, the nature and composition of the clouds, etc.

• With no heat shield or parachute, the bus made upper atmospheric measurements down to an altitude of about 165 km before disintegrating on December 9, 1978.

Pioneer 2 Large Probe that entered the atmosphere

• Had parachute• a neutral mass spectrometer to measure the atmospheric composition• a gas chromatograph to measure the atmospheric composition• a solar flux radiometer to measure solar flux penetration in the

atmosphere• an infrared radiometer to measure distribution of infrared radiation• a cloud particle size spectrometer to measure particle size and shape• a nephelometer to search for cloud particles• temperature, pressure, and acceleration sensors

3 small probes

• No parachute

Venus Express

• Launched November 9, 2005 (Soyuz-Fregat from Baikonur, Kazakhstan)

• First global monitoring of composition of lower atmosphere in near-infrared transparency ‘windows’

• First coherent study of atmospheric temperature and dynamics at different levels of atmosphere, from surface up to ~200 km

• First measurements from orbit of global surface temperature distribution

Mostly spare parts from Mars Express or Rosetta

• ASPERA-4 - Neutral and ionised plasma analysis - Mars Express

• MAG - Magnetic field measurements - Rosetta Lander • PFS - Atmospheric vertical sounding by infrared Fourier

spectroscopy - Mars Express • SPICAV - Atmospheric spectrometry by star or Sun

occultation - Mars Express • VeRa - Radio sounding of atmosphereFrance)VeRaRadio

sounding of atmosphere - Rosetta • VIRTIS - Spectrographic mapping of atmosphere and surface

- Rosetta • VMC - Ultraviolet and visible imaging Mars Express and

Rosetta

• http://www.hulu.com/watch/94012/the-universe-mercury-and-venus---the-inner-planets

Any Questions?