Human evolution overview | 地球上和宇宙中的生命 | Cosmology & Astronomy | 可汗学院

An overview of human evolution. 由萨尔·汗（Sal Khan）创建.

观看下一课: ❤️情人节美甲💅教程#20nails://www.khanacademy.org/science/cosmology-and-astronomy/life-earth-universe/humanity-on-earth-tutorial/v/understanding-calendar-notation?utm_source = yt&utm_medium = desc&utm_campaign=cosmologystronomy

错过了上课? ❤️情人节美甲💅教程#20nails://www.khanacademy.org/science/cosmology-and-astronomy/life-earth-universe/history-life-earth-tutorial/v/first-living-things-on-land-clarification?utm_source = yt&utm_medium = desc&utm_campaign=cosmologystronomy

Cosmology & Astronomy on Khan Academy: The Earth is huge, but it is tiny compared to the Sun (which is super huge). But the Sun is tiny compared to the solar system which is tiny compared to the distance to the next star. Oh, did we mention that there are over 100 billion stars in our galaxy (which is about 100,000 light years in diameter) which is one of hundreds of billions of galaxies in just the observable universe (which might be infinite for all we know). Don’t feel small. We find it liberating. Your everyday human stresses are nothing compared to this enormity that we are a part of. Enjoy the fact that we get to be part of this vastness!

关于可汗学院: 可汗学院提供练习练习, 教学视频, 以及一个个性化的学习仪表板，使学习者能够按照教室内外的步调学习. 我们解决数学, 使用人类有史以来最大的机器, 计算机编程, 历史, 艺术史, 经济学, 和更多. 我们的数学任务指导学习者从幼儿园到微积分的学习者使用最先进, 识别优势和学习差距的自适应技术. 我们还与NASA这样的机构合作, 现代艺术博物馆, 加利福尼亚科学院, 并提供专业内容.

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