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Home , Europa (moon), Life on Venus, We Are All Made of Stars

330 HW 2

•! Stanley Swat This class (Lecture 12): http://www.ufohowto.com/ in the •! Lucas Guthrie Next Class: http://www.crystalinks.com/abduction.html Life in the Solar System

HW 5 is due Wednesday

Music: We Are All Made of –

Presentations Outline

•! Daniel Borup •! Life on ? Futurama •! Life on ? Life in the Solar System? – Venus comparison

•! We want to examine in more detail the backyard of humans.

•! What we find may change our estimates of ne.

Radius 0.95 Earth 0.91 Earth Venus is the hottest 0.81 Earth , the closest in Distance from 0.72 AU size to Earth, the closest Average Temp 475 C in distance to Earth, and Year 224.7 Earth days the planet with the Length of Day 116.8 Earth days longest day. 96% CO2

What We Used to Think Turns Out that Venus is Hell

Venus must be hotter, as it is closer the Sun, but the cloud •! The surface is hot enough to melt lead cover must reflect back a large amount of the heat. •! There is a runaway •! There is almost no In 1918, a Swedish chemist and Nobel laureate concluded: •! There is rain •! Everything on Venus is dripping wet. •! Most of the surface is no doubt covered with swamps. •! Not a place to visit for Spring Break. •! The constantly uniform climatic conditions result in an entire absence of adaptation to changing exterior conditions. •! Only low forms of life are therefore represented, mostly no doubt, belonging to the vegetable kingdom; and the organisms are nearly of the same kind all over the planet.

http://www.daviddarling.info/encyclopedia/V/Venuslife.html Our “Twin” Our “Twin” •! Always covered in thick •! Often called the morning

clouds of CO2, which or the evening star. make it the hottest planet 3rd brightest object in the in the Solar System. sky. •! Pressure on surface is 90 •! Often mistaken for a times that on Earth– like UFO. 1 km under the sea •! Retrograde rotation – Sun rises in west •! No , no

http://antwrp.gsfc.nasa.gov/apod/ap960923.html http://antwrp.gsfc.nasa.gov/apod/ap960923.html

Soviet Satellites on Venus The Venusian Surface Revealed

•! We can’t see Venus’ surface in visible light, clouds block the view •! ’s Radar showed the surface •! Most of surface is smooth lava flows •! Many large volcanoes •! Probable ongoing Mostly Basalts-like rocks, indicative of volcanoes Venus: surface features Surface of Venus: Radar

10,000 km

Maxwell Montes (65N 5E) (Highest mountain range in the solar system 11km high– Everest is 8km)

http://www.solarviews.com/cap/venus/vidven1.htm http://www.geology.smu.edu/~dpa-www/venus.html

Impacts on Venus Venus’ Interior

•! Venus’ size and •! Venus has about Core 1,000 craters, often are roughly clustered equal to Earth’s •! No trace of heavy –! Indicates core of bombardment similar size •! Cratering rate •! No magnetic field indicates Venus’ –! Very slow rotation - surface about 243 Earth days 500 million yrs old •! Why? Crust –! Possibility: Extreme soften , making the surface subject to catastrophic volcanic upheaval Runaway Greenhouse What Happened to Venus?

•! On Earth, greenhouse •! It really should have been more like Earth, but the gasses insulate us atmosphere is much different.

–! Keep Earth 35 K warmer •! Earth’s atmosphere is mostly O2 from life, but early Earth than it would be otherwise was N. •! On Venus, massive •! Earth and Venus have similar amounts of carbon & amounts of CO2 keep it nitrogen, but… incredibly hot –! Almost 300 K warmer! –! The hottest planet in the Solar System

http://www.digitalart.ab.ca/art/ren/images/birth-of-venus.jpg

Why So Different? What Happened to Venus?

•! Apparently Venus lost its H2O– no and no sediments. •! Earth’s carbon is locked up •! Probably the atmospheric was hot enough for –! Dissolved in the oceans water to travel high enough to be broken apart by UV radiation, the H was lost –! Locked into rocks and life and the O reacted with something else. •! Irreversible procedure! •! Which is why greenhouse effect is •! Venus’ carbon is in its atmosphere worrisome here too! –! Too close to the Sun for liquid water •! The Earth traps in the cool tropopause at 14km. –! No oceans to trap the –! No life to process the carbon into sedimentary rocks http://photos1.blogger.com/blogger/4103/1148/1600/Venus%20Wimbeldon05.jpg

http://www.edgechaos.com/MECA/WALLART/VR89/venus.jpeg ? Chemical Disequilibrium

•! Surface is far too hot •! High clouds in the atmosphere contain chemicals –! If lead is liquid, think of what heat would do to that hint at the presence of some kind of complex organic polymers biological activity. –! No cooler polar regions exist •! and dioxide - two gases •! Heat is uniform! that react with each other– exists in the clouds. •! But, high in the clouds it should be cooler?! •! Something is probably producing them. •! Maybe life can still exist in •! Hardly any carbon monoxide. So something is the clouds? perhaps removing the gas. •! At 50 km up, the temperature is not too hot and the pressure is 1 atmosphere.

http://www.manson-valley.de/fotogalerie/manson/images/acss/acss_32.jpg

Life on Venus? Earth – Mars comparison

•! One possibility is that microbes living in the clouds could be combining with carbon monoxide and possibly hydrogen sulphide or carbonyl sulphide in a metabolism similar to that of some early terrestrial micro- organisms.

•! Given that the temperature on Venus was once much Radius 0.53 Earth cooler, there may once have been oceans on the planet. Life Surface gravity 0.38 Earth could have started there and retreated to stable niches once Mass 0.11 Earth the runaway greenhouse effect began. Mars has the Solar Distance from Sun 1.5 AU •! Maybe a mission to scoop up some atmosphere? System’s largest Average Temp -63 C , Olympus Max Temp 20 C Mons – 27 km tall. Year 687 Earth days Length of Day 24 hours 39 minutes

Atmosphere CO2 95% What we used to think. Percival Lowell’s Canals

•! Was thought to be similar to •! Evidence for intelligent life? the Earth in many ways. •! Mapped the civilization. • Life was argued to exist on ! •! Influenced culture. Mars by many astronomers. •! The astronomer Schiaparelli announced that he saw regular linear markings on the surface, which he named canali. •! Technically, in Italian means channels, but it was mistranslated to canals.

The Martian Atmosphere •! 95% carbon dioxide •! 0.6% of Earth’s – •! Large daily and seasonal like 40 km altitude on Earth swings in surface •! But too thin for significant greenhouse temperature effect. •! Pressure is too low for liquid water. •! Not protected by a global like Earth’s The Surface of Mars Water on Mars •! Mars is a desert! •! Iron oxide in soil gives reddish cast. •! There is water on Mars –! North and south

polar caps (mostly CO2) –! Some water vapor in the air –! Frost on rocks –! Clouds (ice crystals) •! No liquid water now

http://www.grc.nasa.gov/WWW/PAO/html/marspath.htm

Liquid water on Mars? New Water? •! Water erosion features visible from space •! Atmospheric pressure too low for liquid water to exist •! Perhaps at some point in the past?

“Islands”

Valley networks Erosion Features Flood erosion The Surface of Mars: Opportunity Roving on Mars

http://antwrp.gsfc.nasa.gov/apod/ap040303.html

Standing Water on Mars •! The new data from the rovers are highly suggestive of ancient standing water on the Meridiani Planum. •! 3 pieces of evidence: –! Physical appearance of rocks –! Rocks with niches where crystals appear to have grown –! Rocks with sulfates left after the water evaporated •! Is it a former sea floor or just an area that had ground- Roving on Mars: water? Spirit and Opportunity find evidence of ancient liquid water

http://antwrp.gsfc.nasa.gov/apod/image/0403/ emptynest_opportunity_big.jpg El Capitan Feb 26, 2008 Mars Missions Now Mars Missions Now •! •! Mars Reconnaissance –! Analyze water ice at Mars’ north pole Orbiter –! Studying the geology and climate of Mars –! Look for ancient sea shores –! Survey potential landing sites

http://www.nasa.gov/mission_pages/phoenix/images/ press/PSP_008591_2485_RGB_Lander_Inserts.html

Mars Missions Now Mars’ Watery Past

•! Phoenix –! Confirmed water ice on the surface of Mars –! Sublimates too slowly for dry ice (CO2)

http://www.nasa.gov/mission_pages/phoenix/images/ press/PSP_008591_2485_RGB_Lander_Inserts.html What Happened to the Water? The Geology of Mars

•! That is the big question –! Quite a lot of evidence for water now and in the past. –! Did the surface water escape to space with the air? –! How much is still frozen ! beneath the surface? Opportunity ! Spirit

The Surface of Mars Olympus Mons

•! The largest mountain in the Tharsis volcanoes Solar System rising 26 km high •! A shield volcano, Hellas Impact Basin like Hawaii Valles Marineris on Earth •! Its is 90 km across

http://hyperphysics.phy-astr.gsu.edu/hbase/solar/marsoly.html

Mars Global Surveyor Olympus Mons Valles Marineris

•! Its base is more than 500 •! A series of fault km in diameter canyons •! As long as the entire •! 5000 km long Hawaiian island chain –! A big as the U.S.! •! Rimmed by a 6 km high •! A giant crack in the cliff crust of Mars •! Last erupted 25 million –! Formed as the planet years ago cooled •! Probably so big, due –! Expanded by water flow to lack of

Mars’ Interior Mars’ Past

•! Like Earth, Mars has •! Early in Mars’ history it was an iron core Core likely more Earth-like –! About half of the –! Geologically active planet’s radius in size –! Volcanic eruptions created a thick carbon dioxide, nitrogen –! Heavily contaminated atmosphere with sulfur –! Greenhouse effect made it –! Weak magnetic field warm enough for liquid water suggests a thin layer –! Oceans? Rivers? Glaciers by of liquid iron, mostly Crust Mantle the poles? solid –! Life? What Happened? The “Face” of Mars? (1976) •! Mars was too small Mars Global –! Not enough internal heat Surveyor (1998) •! Plate tectonics stopped –! Volcanoes sat over “hotspots” grew to immense sizes •! Volcanic activity slowed as the interior cooled •! The atmosphere escaped

•! The planet froze http://antwrp.gsfc.nasa.gov/apod/ap980406.html •! Did life move underground? http://antwrp.gsfc.nasa.gov/apod/ap010528.html

Other Faces Other Places

Mars Global Surveyor (1998) " Mars Global Surveyor (1998) "

http://antwrp.gsfc.nasa.gov/apod/ap990315.html http://www.solarviews.com/cap/mgs/heart.htm The Search for Mars Life Martians?

•! Viking 1 and 2 carried several •! In August 1996, evidence for microbial life was experiments to detect life found in a Martian . –! ALH84001 (3Gyrs): •! The results were ambiguous. The Found in , soil reacted vigorously with the composition suggests Viking , then tapered off it was knocked from in activity. Mars •! The conclusion of most scientists –! About 14 such Mars rocks have been found is that the reactions were due to on Earth inorganic chemical reactions. •! David McKay et al. •! Dirk Schulze-Makuch suggested suggested that there was that Mars might harbor peroxide- fossil evidence for based life forms which the bacteria in the meteorite. landers could not detect

Martian Microbe Fossils? &

•! Microscopic shapes that •! Mars’ moons resemble living and fossil bacteria on Earth– •! Likely captured nanobacteria, but much smaller than on Earth. •! Very small •! Microscopic mineral grains –! About 15-25 km in size like some produced by living –! Shaped like potatoes and fossil bacteria on Earth •! Organic chemical compounds that resemble the decay products of bacteria on Earth. •! In the end, not impelling enough. Non-biological processes can probably produce the observed features Manned Mars Exploration Question

•! NASA’s plans to We know for sure that send a manned expedition to Mars •! Timetable: a)! Mars used to have water. –! Complete Space b)! Mars has life. Station by 2010 –! Return to c)! The people of Mars need soap. by 2020 d)! The is gone. –! Then, on to Mars (no date) e)! Mars has water just under the surface now and •! No cost estimates used to have surface water. –! Some funds from to-be-retired shuttle fleet

Question Life in the Solar System •! Venus may have life in the clouds. The face on Mars •! Mars might still have life under the soil. •! But what about the outer solar system? a)! was a huge NASA cover-up. •! It isn’t in our definition of the habitable zone, but it still is interesting. b)! might have been created by Martians or ETs, but •! We will now focus on , , , and . we’ll never know for sure. c)! was an optical illusions, like cloud shapes. d)! will be the major focus of any follow-up rover missions. e)! was really a statue that had fallen over. 143,000 km 1,400,000 km We are here !

Earth – Jupiter comparison Jupiter, King of the

•! Named for the king of the Roman gods •! A truly immense planet –! Over 11 times the diameter of Earth –! Over 300 times the mass of Earth –! Over twice the mass of all the other planets combined! Biggest and most –! Has over 63 moons, its own mini-solar system! massive planet, has the •! Visited by 4 spacecraft The big Radius 11.2 Earth –! - Flyby in 1979 largest gravity, has the Cloud-top gravity 2.5 Earth largest number of –! Voyagers 1 & 2 - Flybys in 1980 & 1981 Mass 318 Earth –! - Went into orbit and dropped a probe into Jupiter’s moons (>63), yet has (more than 2.5 times the rest combined) atmosphere, 1990-2003 the shortest day in Solar Distance from Sun 5.2 AU System. Radiates Year 11.88 Earth years more energy than it Solar day 9 hours 55 minutes absorbs. Causes a bulge at the equator. Jupiter’s Interior Jupiter’s Atmosphere

•! Average density only 30% greater than water •! Although mostly gas, by 20,000 km in, • 25% that of the Earth’s average ! the pressure is 3 million ! density •! By 20,000 km, the pressure is 3 •! Due to an internal heat source, the million times that on the temperature rises as one penetrates the Earth’s surface! atmosphere. –! Hydrogen becomes a liquid •! The outer atmosphere is made of •! Core of rock & “ice” freezing clouds of , , 10-12 Earth and ice. •! The swirling patterns are evidence of great storms.

The Driving Jupiter’s Weather •! A huge storm 25,000 km across – twice size of the Earth! •! On Earth, solar heating drives weather •! First observed > 300 years ago! •! On Jupiter, internal heat drives weather –! Winds maintain speeds to great depths –! Jupiter radiates 70% more heat than it receives from the Sun –! The heat is from Jupiter contracting under its own powerful gravity –! As it contracts, the gas is squeezed, and the temperature increases

Voyager 1 image Cassini images Little Red Spot Life?

•! and Edwin Salpeter devised a scheme for life in the clouds of Jupiter. •! They argued that the atmosphere must be rich in organic chemistry, so why not expect Earth-like life?

http://tierra.rediris.es/merge/Carl_Sagan/192a.jpg http://www.aip.org/history/esva/catalog/images/salpeter_edwin_a3.jpg

Floating Life Floating Life

•! The problem is that any life in the clouds •! The sinkers became the basis of that sank too far down would be destroyed a proposed ecology. by the temperature or pressure. •! They proposed a simple life form like •! They also posited “floaters”– oceanic plankton called “sinkers”. large hydrogen balloon-like life •! Small (0.1 cm) life that grew and fell, but that “swim” in the Jovian then replicated by “splitting-up” and atmosphere. getting circulated back into the upper atmosphere.

http://www.wackerbaits.com/sf/media/bellsinker.jpg http://www.firaxis.com/smac/nativelife.cfm http://www.mantapacific.org/mantapacific/information/images/plankton.jpg Floating Life Floating Life

•! They could be huge •! Maybe there are also “hunters” that fed on the creatures, as large as 1 floaters? to 2 km in diameter. •! Of course, this is all •! Maybe similar to speculative, and there is whales– mixture no way to detect such life. between jellyfish and •! from birds? scientists really. •! Big bags of hydrogen gas.

http://www.epilogue.net/cgi/database/art/list.pl?gallery=3126 http://img.photobucket.com/albums/v154/superminyme/National %20Geographic%20Picture%20Atlas%20of%20Our %20Universe/Pg4JupiterPic.jpg

Jupiter’s Magnetosphere Jupiter’s Rings

•! Liquid metal •! Jupiter has rings! hydrogen •! Discovered by the generates a Voyagers magnetic field –! 14x stronger •! Not prominent like than Earth’s field ’s –! Over 4 million km •! Dusty disk of debris, across probably from •! A ring of ionized impacts particles surrounds J. Spencer with small moons Jupiter –! Stripped from Jupiter’s moon Io The Io

•! Innermost Galilean moon – the “pizza moon” •! Io is active. •! The most volcanically active body in the solar system. •! Europa is now thought to be the best option for life. •! discovered presence of volcanoes •! Internal heating by Jupiter’s tides •! But, and are contenders perhaps •! Atmospheric gases ripped off by Jupiter’s magnetic field – ion torus for ancient life.

Pillan Patera eruption Before & after

Europa Europa •! Slightly smaller than our Moon. •! Icy crust 5 km thick. Can protect life against magnetic fields. •! Evidence for deep (50 km!) liquid water beneath crust– remains liquid from tidal forces from Jupiter •! Cracks and fissures on surface – upwelling?

•! Young surface – few craters •! Tidal forces pull and push the ice –! Like Io, it probably has strong tidal forces.

Galileo Europa

•! Life would have to be below the surface, around hydrothermal vents. •! Very encouraging, as early life on Earth, might have been formed around such vents. •! We don’t how thick the ice is yet. •! Future missions, will have to employ melting or smash and dive spacecraft.