Habitability

How Earth Became HabitableHabitabilityObviouslyThe planet has to form first.check your notes on planet formation.Conditions necessary for HabitabilityA planet or planetary satellite is said to be habitable if it can sustain life that began there or was brought there. (NASA)The first thing astronomers look for is liquid water.The planet cannot be too hot or too cold, it must be just right (goldilocks zone)Generally, we believe there must be an atmosphere or another method to protect life from harmful radiation

Habitable zone (Goldilocks)

Habitability in our Solar SystemThe only known habitable planet in our solar system is planet Earth.Current research is looking at the moons of Jupiter and Saturn as possible habitable locations.

EuropaHabitability outside our Solar SystemWith new technology we have been able to discover over 450 extra-solar planets (planets outside our solar system)So far most of what we discovered are huge gas giants larger than Saturn.These are unlikely to support lifeStatistically speaking in our Galaxy (the milky way) there are estimated 10,000,000,000 Earth-like planets

Earths First AtmosphereThe creation of the Earth through collisions initially left the surface of the planet moltenEarth slowly cooled and formed a solid crustThe gasses that were originally dissolved in the molten rocks were releasedEarths first atmosphere resembled the gasses from volcanic eruptions.The first atmosphere was composed of Water vapor, carbon dioxide, nitrogen and several trace gasses. No oxygen!Evolution of Earths AtmosphereAs the planet continued to cool the water vapor in the atmosphere fell as rainRain evaporated before or upon reaching the surfaceEvaporation increased the rate of coolingEventually water accumulated in the low areas creating oceans and seasMost of the Carbon dioxide was dissolved in the oceansThe remaining atmosphere was Nitrogen richContinued EvolutionEventually primitive organisms started to use photosynthesis to generate energyThis produced a byproduct of oxygen gasInitially the oxygen gas would attach to metals (iron oxide, aluminum oxide etc)Eventually the oxygen collected in the atmosphere (2.5 billion years ago)Earths Evolving Atmosphere

Composition79% N2 Nitrogen gas20% O2 Oxygen gas.93% Argon an inert (Noble) gas.039% Carbon Dioxide (CO2)Although it only makes a small percent it has large impacts globally.031% other gasses

Your Project: Poster FunYou and your partner will be researching an object in the solar system and making a poster presenting its possible habitabilityMain Points:Compare your object to earthPositives (assets)Negatives (challenges)How to overcome the challenges (What would daily life be like on your object? Travel time there and back?)Comparing to earthGravityAtmosphereSurface conditions (climate, temperature)ResourcesPositives should includeWhat requirements for habitability are present?What reasons do you have for going there?MoneyMineralsScientific PurposesNegativesDrawbacks to living thereWhat doesnt your object have?What would need to be shipped?CostsOvercoming ChallengesLiving StructuresTechnologyDaily LifeTransportationFoodWaterAirProtection from radiationTemperature controlThere and back againTopic ChoicesMercuryVenusLunaMarsCeresIoEuropaCallistoGanymedeTitanIapetusMirandaOberonTritonVestaHaumeaSednaGrading RubricPoints 543210Ontime completionTues. Beginning of classTues. in classTues. end of the dayWed. before schoolWed. beginning of classAfter thatEarth ComparisonSuperior CompletionAll topics CoveredMissing one topic/Badly doneMissing two topics/Badly doneMissing Three/Badly doneDidnt DoProsSuperior CompletionAll topics CoveredMissing one topic/Badly doneMissing two topics/Badly doneMissing Three/Badly doneDidnt DoConsSuperior CompletionAll topics CoveredMissing one topic/Badly doneMissing two topics/Badly doneMissing Three/Badly doneDidnt DoOvercoming Challenges (X 2)Superior CompletionAll topics CoveredMissing one topic/Badly doneMissing two topics/Badly doneMissing Three/Badly doneDidnt DoBibliography3 or more citations/MLA or APA3 or more, bad format2 proper format2 bad format1 good format 1Bad format or not done19