Study Guides (238,612)
Canada (115,252)
York University (9,816)
NATS 1540 (22)

NATS 1540 - Review Lecture 1-5.doc

10 Pages
Unlock Document

York University
Natural Science
NATS 1540
Robert Levine

Lecture#1: Birth of the Planet No water, no oxygen, just toxic gas Collision course with another young planet (Thera) nearly oblibrated the Earth - instead created life on Earth as we know it Planetary Scientists discover Earth`s history by studying neighbour planet`s surfaces o Surfaces on the planets of Jupiter and Mars Earth`s axis of 23 degree + we have a moon = Earth was explosive Thera and Earth`s collision = leftover red dust and rocks that became the Earth`s moon over the next 100 years Lunar samples similar, represents the outer edges of the Earth`s crust - the moon born from the Earth Creation of the moon led to may events to create Earth (now) Coral samples and fossils from ancient oceans showed that long ago: o There were 410 days in a year o Millions of years ago, days were shorter, only 21 hours the Earth spun faster than now o After the collision, days were 6 hours long only; spun x4 faster o Moon was x10 closer; Earth became a hostile env. Young planet (Earth`s) being devoured by the oceans o Taken resources and minerals from the water to give to the lands - created LIFE ! o Tides form due to close proximity of the moon - tides = life Studies ancient and modern bacteria - found that they were similar Tidal friction = tides + continents meet, friction created; slowing down the Earth o The deceleration of the Earth`s spin made the days longer = more liveable Tides are pushing the moon away - gravity o Gravity from water acting against the moon, pulling the moon further away, almost ripping the Earth apart Photosynthesis is created - oxygen used but poisonous at first o Oxygen = poison, take away the harmful bacteria few survived = good ** Catastrophe is always the beginning of something 600 mya - PALAEOZOIC ERA (1st life - Ancient celled organisms Primary) : (ex. simple fishes) 250-75 mya - MESOZOIC ERA (middle - Amphibians and reptiles life - Secondary) : (ex. shells, fishes, land-living saurians - crawlers) 75 - 10 mya - TERTIARY or CENOZIC Mammals, birds ERA ( recent life) : 10 mya - present - QUATERNARY Modern plants and animals (recent life) : MESOZOIC 1. Triassic Period (245-200 mya) 2. Jurassic Period (200-144 mya) 3. Getaceous Period (144-63 mya) Lecture#2 : Prehistoric Disasters Snowball Earth 650 million years ago Temperatures plummet glaciers take over the planet covering the entire globe with ice 25 million years before it defrost Life was just beginning to grow now covered in ice Proof hidden away in some of the worlds most hidden parts Investigation by air Every layer of rock holds a secret Dried up creek bed a drop stone The drop stone must have been transported from hundreds of miles away Only force able to transfer it is ice Glaciers transfer/transport heavy materials hundreds of miles thousands of tons of rock When glacier melts away rocks, sand/ mud is exposed Same process that transfers the drop stones Earths surface in steady constant motion pushing continents around Must determine the area of each continent Death valley of U.S. gathering evidence to support theory Very hot area, no signs of ice/ glaciers Many random rocks obviously out of place 650 million years ago, it was sealed in ice Drop stones there date back to the same time as those found in Flinders Measuring a piece of the drop stone to determine its magnitude to locate its origin Each rock has its unique magnetic signature - measures magnetic fields Figure out the latitude rock forms - determines where they`re from 650 mya, Australia used to be near the equator during the ``big freeze`` If a country so close to the equator is covered in ice the entire planet = snowball earth Whole world seemed to be buried alive ice age end of earth Ice age the further the earth moved from the sun, the colder it got Ice ages occur every 100 000 years or so Triggered in changes of planet`s orbit around the sun ``smoking gun`` Imbalance not enough carbon oxide , too much greenhouse gas greenhouse gases make the planet what it is today - balancing act If CO2 gets too high or low, the planet will spiral into downfall Something must be taking CO2 out weathering Acid rain is formed when hitting rock , washes into the oceans, washed to the bottom of limestone locked the CO2 into the rocks CO2 levels crashes as well as Earth`s temperatures - must cool down Earths surface includes land surface, and water Each reflect sunlight in different ways Ratio of earths reflective surfaces thrown off everything off Best reflector = sea ice , worst = sea water Less sea water = less warmth Tipping points must find a balance Once balance is breached , planet can no longer keep ice in check Ice eventually shut off the entire planet life seems doomed Deep beneath the ice sheets life/ bacteria seem to become extinct How could any living thing survive the deep freeze Life/ bacteria learned to adapt Extremophiles live in extreme conditions Learn to live in the extreme, cold conditions of a cave If taken away from their conditions they will die May relate back to the earliest survivors Unlike humans they can endure some of the most extreme conditions on earth once adding water to a bacteria, they begin photosynthesis again Even in the harshest conditions, earth will find a loophole After 25 million years of deep freeze, salvation is on its way Ice sheets begin to defreeze / getting warmer from the inside of earth Mount Augustine volcanoes are the only things strong enough and warm enough to warm/ melt all the ice and save the world Eruption so powerful that the volcano actually grew Volcano eruption forms many greenhouse gases Billions of tons of carbon dioxide levels produced from the eruption over 1000 years Snowball earth is finally over Species that l
More Less

Related notes for NATS 1540

Log In


Don't have an account?

Join OneClass

Access over 10 million pages of study
documents for 1.3 million courses.

Sign up

Join to view


By registering, I agree to the Terms and Privacy Policies
Already have an account?
Just a few more details

So we can recommend you notes for your school.

Reset Password

Please enter below the email address you registered with and we will send you a link to reset your password.

Add your courses

Get notes from the top students in your class.