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Course: Big History Project > Unit 4
Lesson 3: Why Is Plate Tectonics Important? | 4.2WATCH: The Solar System & the Earth
Emily Graslie joins John and Hank Green to discuss the formation of our Sun, Solar System, and Earth - and how it's all slightly more interesting than leftover crumbs and clam chowder. Learn how we're all essentially 'lava surfers' as you investigate how geological processes related to plate tectonics shape our daily lives. Created by Big History Project.
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What does it mean to be a gas giant? I understand the giant part as much as a human brain can understand such huge sizes, but the gas part makes me think that the planets don't have a ground and they're just soupy elements maybe cuddling with some kind of solid core, and maybe the planet is teeming with deep-dwelling sea monsters...(8 votes)
Great question! Gas giants are hard to get a grasp on unless you understand some advanced physics, so I've linked in the basic principle below. Scientists still debate on whether gas giants are solid all the way through or if there is an honest to goodness core. In either case, pressure and heat builds as you move inwards until gases become metallic (not solid or liquid, still gaseous yet capable of conducting electricity!). As for the incomprehensible part, gas giants range from around twice to ten times the size of Earth. Sal made a video on scales in the Universe if you have a hard time understanding this. It is improbable that life would evolve in such an extreme environment, and they definetely wouldn't resemble any deep ocean creature we could imagine, but life on the moons of gas giants is a real possibility (as some, like Europa, have liquid water beneath their surfaces!).
https://en.wikipedia.org/wiki/Triple_point
https://www.khanacademy.org/science/cosmology-and-astronomy/universe-scale-topic/scale-earth-galaxy-tutorial/v/scale-of-solar-system(5 votes)
Isn't calling Pluto a "planet" an example of folk taxonomy? Grouping things according to the less precise criteria that people use in general discussion and thinking? If so, what's wrong with folk taxonomy? Science has its criteria for classifying things and people have other less formal criteria. Why not just acknowledge that these are two separate ways of describing a set of facts and let that be the end of it without nitpicking where nitpicking might not be appropriate.(7 votes)
pluto is a dwarf planet so its not a real planet.(0 votes)
What is Helium?(3 votes)
Helium
Chemical Element
Helium is a chemical element with symbol He and atomic number 2. It is a colorless, odorless, tasteless, non-toxic, inert, monatomic gas, the first in the noble gas group in the periodic table. Wikipedia
Symbol: He
Atomic mass: 4.002602 u ± 0.000002 u
Atomic number: 2
Discovered: 1868
Electron configuration: 1s2
Melting point: -458°F (-272.2°C)
Discoverers: Pierre Janssen, Norman Lockyer(5 votes)
Who's Emily, the person who explained the Solar System forming?(2 votes)
She also worked on Crash Course for the second season on Big History.(3 votes)
Why is the planet has super volcanos?(2 votes)
The similar reason to todays volcanoes. The crust rubbs against other plates(ame thing as arthquakes).The enormous build-up of heat and pressure caused mountaians,and essentially, volcanoes. Just there were more super volcanoes back then because the planet was already extremely hot and had much more lava.(2 votes)
did you all here that cat meow in the first twentyfive seconds listen closely and slow the video down to 0.5(2 votes)- So is like forming planets like playing agar.io?(2 votes)
- Oversimplification, but yes! Except it isn't perfect, stuff will get flung into space.(1 vote)
- Why earth got gravity, air and life?(2 votes)
It's all just chance. If Earth was in a different location or if some of the things that happened in its early stages didn't happen we wouldn't be here at all, but part of the reason why life DOES exist is that we have water, which is essential for life. We also got a perfect location, not too hot and not too cold, and as the earth is not a gas giant, we can stand on it and all those other stuff.(0 votes)
aren't black holes just undead zombie stars, looking for things to consume(1 vote)
what does Goldilocks have to do with the solar system?(0 votes)
For many years scientists looked around the solar system. Mercury and Venus were too hot. Mars and the outer planets were too cold. Only Earth was just right for life, they thought. Our planet has liquid water, a breathable atmosphere, a suitable amount of sunshine. Perfect.
https://smd-prod.s3.amazonaws.com/science-red/s3fs-public/mnt/medialibrary/2003/10/01/02oct_goldilocks_resources/earth_med.jpg Right: Earth photographed by the crew of Apollo 17.
It didn't have to be that way. If Earth were a little closer to the sun it might be like hot choking Venus; a little farther, like cold arid Mars. Somehow, though, we ended up in just the right place with just the right ingredients for life to flourish. Researchers of the 1970s scratched their heads and said we were in "the Goldilocks Zone."(2 votes)
