Big Historyの授業を受けています

moocでbig history(https://www.coursera.org/learn/bighistory)についての授業を受けています。4週間コースなのですが今日一周目が終わりました。今回のコースには受講生同士による相互評価テストがありました。今回はその原稿を載せます。

まずは原稿の前に課題について。今回の課題は「自分の宇宙に関する知識と自分で選んだ地上の物との関係性について、自分で質問を作ってそれにこたえる(200~400 words)」でした。テーマを決めるのが意外と簡単なようで難しく期限の今日まで来てしまい急いで仕上げました。

選んだテーマはろうそくの炎についてです。宇宙ではどのように燃えるのかについて書きました。

The flame of a candle have a pointy tip and the color is red, on the earth. You may think it's the same in space, but is it? I'll describe how does a candle burn in a space craft and the reasons.
The appearance of a candle flame in space is very different from that on the earth. First is the shape. On the earth, it get's thinner toward the tip, but in space, the tip is round and it looks like a mushroom. The reason is zero gravity. On the earth, air flows upward from the base of the candle, so the flame become slender. On the other hand, in space, because it is in zero gravity, there is no air circulation, so the air doesn't flow up and the flame becomes like a round sphere. Second is the color. On the earth, the center of the flame is blue, and the rest is red, but all parts are blue in space. The reason is related to the first one. Because there is no air circulation, as I said, new air is no longer supplied to the flame. This makes the temperature of the flame lower, and the color becomes blue.
In conclusion, in space, there is no gravity and no air circulation so that the flame become round and blue. And I think this may makes us to be able to do something that we can't do on the earth in space.