Snowball Earth: Mission to Planet Earth in the Distant Past
In this class, we've learned about our planet, the Earth, and about many other planetary bodies in our solar system. We've seen that there are many interesting similarities and differences between them. The Earth resides in the warm inner solar system, near the Sun, but Venus and Mercury are even hotter than the Earth. Most of the solar system is farther from the Sun than the Earth is, so we've learned about things like ice on Mars, on Europa, on Enceladus, etc..., and even about signs of liquid water beneath the surfaces of some of those bodies.
For this question, you're going to imagine you're a space alien living about 650 million years ago, on some other planetary body (like Mars or a moon of an outer planet), and you're studying the Earth.
Let's imagine this alien species has evolved much like humans have, and has senses similar to ours, and a level of intelligence like ours, and has developed science much like we have today.
So there you are - it's about 650 million years ago, and you're a space alien with human-like senses and intelligence, and a level of scientific and technological development like early 21st-century humans have. Just because you're a space alien, it doesn't mean you have super-duper advanced technology. You've got late-20th to early-21st century technology, if we're making a comparison to humans.
Now, here's the thing - 650 million years ago, the Earth was weird! It was going through a strange episode in its history called Snowball Earth. (In fact, there were more than one of these "snowball" episodes. The most recent one was about 650 million years ago. Complex multicellular life evolved on Earth about 540 million years ago.)
Scientists aren't sure if the Earth totally froze, with the oceans and continents completely covered with ice, but let's assume it did. Nothing but white everywhere. Like the ice planet Hoth from "The Empire Strikes Back". Kind of like the illustration in this article about Snowball Earth.
Method 2 - To get ALL of the possible points
Question: But what if... just what if... you just might be so gosh-darn smart, you can solve this problem without a space program! You can solve it with the technology of the late 1700s! Imagine you're sitting there listening to Hamilton - those people could have solved this problem!
How would they have done it? I wonder... hmm...
If you can figure out the low-tech, pre-space-age, could-have-been-done-200-years-ago method, you can write it in a few short paragraphs, like a medium-sized Discussion post
THE SOLAR SYSTEM
The sun is a vast ball of gas namely hydrogen, helium and dust formed about 4.6 billion years ago. some spread out as spinning disk and clumped together to form orbiting planets of the solar system. the four small inner planets namely, Mercury, Venus , Earth and Mars are made up of rocks and the outer planets namely, Jupiter, Saturn, Uranus, Neptune are made up of gas and ice. there are also a few dwarf planets namely Pluto, Eris and billions of small rocky asteroids.
MERCURY - smallest of the inner planets, closest to the sun, contains craters and thin atmosphere, temperature at day is 430 degree centigrade and at night is -180 degree centigrade.
VENUS - contains volcanoes, thick atmosphere with CO2, hottest of the planets with temperature 464 degree centigrade.
EARTH - water is present in liquid form, atmosphere act as blanket, acts as GOLDILOCKS PLANET meaning the atmosphere is not too hot nor too cold.i.e, perfect for human life.
MARS - red colour in appereance, cold and dry, thin atmosphere with CO2, water is present in the form of ice.
JUPITER - thick atmosphere of H and He, has 63 moons, has great red spot is a huge storm and wider than earth.
SATURN - has rings with 60 moons, made up of mainly H and He.
URANUS - made up of ice and frozen gases namely methane and ammonia, has 27 moons.
NEPTUNE - most distant with temperature -200 degree centigrade, has one large moon called Triton and 12 smaller ones.
SNOWBALL EARTH HYPOTHESIS
this is most popular yet controversial hypothesis which inquires the scientists mind and now behaves as strong evidence for global glaciations , 650 million years ago. it shows much about the paleoclimate of that time from studying the carbonate debris found in glacial deposits and shallow marine carbonates known as cap carbonates. in this phase of time, the entire earth freezes over and then thaws.
although controversial but snowball earth model explains most of the data like,
1)incomplete freezing of oceans permits the survival of multi cellular life.
2)atmospheric CO2 levels are very low that time leading widespread glaciation.
3)breaking of super continent Rodinia must have taken place producing new plate margins.
this model of glaciation how ended up is also an interesting topic for discussion?