So I have recently fallen in love with this site.

It's called Khan Academy and I love it. It offers free education to anyone willing to learn.
You get your little character and it evolves along as you learn new stuff, so it's good for kids too.

Both the concept of free education and the way they made it happen swept me off my feet, so I decided to dedicate today's lesson to science!

General Japanese term for it is:

科学
かがく
Science

By itself, 科 can mean 'section, department' and 学 means 'learning / knowledge'
...so something like 'compartmentalized learning', if I may?

Anyways, careful not to get it mixed up with '化学/かがく/chemistry', as it is pronounced the same.

But this one is easy to remember as it spells 'the knowledge of change', with '化/か' standing for 'change'.

I think we should start from the very beginning.

As you may know, everything started with the?

Yep, hooray for katakana! 'The Big Bang' in Japanese is 'ビッグバン' . They couldn't have made it easier.

Still, they have a (much less common) kanji word for that too. So for those of you who can't get enough of counting strokes and remembering all the different readings on top, here you go, I am happy to spoil you:

宇宙大爆発
宇　　宙　　 大　　爆　　 発
う　ちゅう　 だい　 ばく　はつ
Big Bang
Literally: 'Space + big + explosion'

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Legend says the first atoms that formed after the universe came into existence were helium and hydrogen. So what do we call that?

And what do we call an atom in the first place?

原子 / げんし / Atom is made up of '原' which stands for 'origin, primitive' and '子' that stands for 'child' . So if you put it together... well... I don't really know how to make sense of it but I can feel some dots connecting in my brain.

Now we have

水素
すいそ
Hydrogen
Literally: 'water + plain / original / base or root (of smth.)'

and

ヘリウム
へりうむ
Helium

and one we really couldn't live without:

酸素
さんそ
Oxygen
Literally: 'acid + plain / original / base or root (of smth.)'

Now this one is a little stretched, but I think of it like this. To get acid stuff like vinegar you require fermentation, and oxygen plays a very important role in the success of the fermentation process. That's why wine remains intact sealed in a bottle (and kept in dark places) and once you pour some in a glass and leave it on the kitchen counter, it won't take more than a day for it to turn sour.

... so oxygen is the origin of acid stuff? Yeah, I know, for someone wanting to talk about science I made a terrible job at reasoning my way out of this.

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But let's continue our little journey across the universal beginning. All we got was 水素 and ヘリウム. So... then what? Well these two little elements, they got together into a big cosmic party. And as more and more arrived, things got heavy, with the force of gravity pulling them closer and closer.

Wait a sec, gravity?

重力
じゅうりょく
gravity
Literally: 'the force of heaviness'

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So after they all got really close, things ummm, heated up a little.

Actually not just a little, they got really really hot, really really fast!

And bam! You get nuclear reaction. If they get hot enough (10.000.000 degrees Celsius) they officially become a star.

Now, just one more and then we'll recap.
Nuclear reaction?

核反応
かくはんのう
Nuclear reaction
Literally: 'Nucleus / core + reaction'

So yeah :)

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Now, let's pretend you didn't know any of this and ask me:

星はどうやってうまれるのですか。
ほし　は　どうやって　うまれた　の　です　か。
How do the stars get born?
Literally: 'Stars + は + how + become born + の + です + か.'

I could reply:

宇宙がビッグバンで生まれたとき、たくさんの水素とヘリウムのガスができました。
うちゅう　が　びっぐばん　で　うまれた　とき、　たくさん　の　すいそ　と　へりうむ　の　がす　が　できました。
When the universe came to be through the big bang, a lot of helium and hydrogen gas was created.
Literally: 'Universe + が + Big Bang + で + got born + when, + a lot + の + Hydrogen + と + Helium + の + gas + が + appeared.'

いま私たちが見ている星はみんなこのガスからできています。
いま　わたしたち　が　みている　ほし　は　みんな　この　がす　から　できています。
The stars we are looking at now are all made from this gas.
Literally: 'Now + we + が + looking + stars + は + all + this + gas + from + created.'

For the finale, I want to leave you with the knowledge that all the other elements we know were made in the warm belly of a nuclear reacting sun that proceeded to end its life with a bang (supernova explosion). Thus happened that oxygen, carbon, iron, and all other elements came to spread through the universe, fresh out of the oven.

Which brings me to my cheesy line for the day: We are all, quite literally, made up of stardust.

Have fun with your studies and see you next time!

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This lesson was written by Adriana, a guest contributor.