城市灯光在下方划过, 拍摄于国际空间站 City lights streak below, taken from the International Space Station (© NASA)

城市灯光在下方划过, 拍摄于国际空间站 City lights streak below, taken from the International Space Station (© NASA)

离开地球的第一步 The first step off Earth

国际人类航天日

今天，世界纪念国际载人航天日，这是联合国设立的纪念日，旨在纪念人类首次进入太空的旅程以及人类太空时代的开始。这个日期回忆起1961年4月12日，尤里·加加林绕地球飞行，证明人类可以离开地球并安全返回。

这种探索精神在国际空间站上依然存在。从国际空间站上，宇航员拍摄发光的城市网格和穿越地球大气层的强烈雷暴——这些景象将科学变成了魔法。空间站绕地球运行的高度大约为250英里，每90分钟环绕地球一圈，使船员每天最多可以看到16次日出和日落。自2000年以来，空间站一直有人居住，由美国、俄罗斯、欧洲、日本和加拿大的合作伙伴共同运营。在空间站内部，宇航员进行推进医学、材料和气候科学的研究，同时也学习人类如何在离地球更远的地方生活和工作。

International Day of Human Space Flight

Today, the world marks the International Day of Human Space Flight, a United Nations observance honoring the first human journey into space and the start of the space age for humanity. The date recalls April 12, 1961, when Yuri Gagarin orbited Earth, proving that people could leave the planet and return safely.

That spirit of exploration lives on aboard the International Space Station. From the ISS, astronauts photograph glowing city grids and powerful lightning storms streaking through Earth's atmosphere—views that turn science into magic. Orbiting about 250 miles above the planet, the station circles Earth every 90 minutes, giving crews up to 16 sunrises and sunsets a day. It has been continuously occupied since 2000 and is operated by a partnership of the United States, Russia, Europe, Japan, and Canada. Inside, astronauts conduct research that advances medicine, materials, and climate science, while also learning how humans can live and work farther from home.