人造卫星为什么不会掉下来？
Why don't satellites fall down?
卫星飞得非常快，向前的速度让它在下落时刚好绕过地球的弧面。它其实一直在坠落，却永远落不到地面。
A satellite moves forward so fast that as it falls it keeps curving around the bend of the planet. It really is always falling, yet it never reaches the ground.
难度 入门 · 适合 小学低段(6-8)
CC BY 4.0 · 已核验 · Verified 2026-08-23 · 2 条独立证据
来源 · Source
Carl Sagan,《Cosmos》Random House,1980;中译《宇宙》
C. Sagan, Cosmos, Random House, 1980; Chinese ed.
独立核验依据 · Independent verification: 核验依据 2 DOUBAN ISBN 标识 9780394502946（按标识回读: Cosmos）
#卫星 #轨道
韦布空间望远镜为什么要观测红外线？
Why does the James Webb Space Telescope observe in infrared?
极遥远星系发出的光在膨胀的宇宙中被拉长，抵达我们时已变成红外线。红外线还能穿过尘埃云，让人看清里面正在形成的恒星。为了不被自身热量干扰，这台望远镜必须保持极低温。
Light from the most distant galaxies is stretched by cosmic expansion and arrives here as infrared. Infrared also passes through dust clouds, revealing the young stars forming inside them. To avoid being swamped by its own heat, the telescope must be kept extremely cold.
难度 入门 · 适合 小学高段(9-12)
CC BY 4.0 · 已核验 · Verified 2026-11-03
来源 · Source
Gardner J. P. et al., The James Webb Space Telescope, Space Science Reviews 123 (2006), DOI: 10.1007/s11214-006-8315-7
Gardner J. P. et al., The James Webb Space Telescope, Space Science Reviews 123 (2006), DOI: 10.1007/s11214-006-8315-7
独立核验依据 · Independent verification: 核验依据 1 INSPIRE 标识 10.1007/s11214-006-8315-7：The James Webb Spac
#韦布望远镜 #红外线
既然黑洞不发光，人类怎么拍到它的照片？
If a black hole gives off no light, how did we photograph one?
照片上显示的不是黑洞本身，而是它周围被加热到发光的气体，以及中央那片黑色阴影。2019年，事件视界望远镜把分布在全球的射电望远镜联合起来观测，得到了第一张这样的图像。
The image does not show the black hole itself but the glowing hot gas swirling around it, with a dark shadow at the centre. In 2019 the Event Horizon Telescope linked radio dishes across the globe to capture the first such picture.
难度 入门 · 适合 小学高段(9-12)
CC BY 4.0 · 已核验 · Verified 2026-11-03
来源 · Source
Event Horizon Telescope Collaboration, ApJL 875, L1 (2019), doi:10.3847/2041-8213/ab0ec7
Event Horizon Telescope Collaboration, ApJL 875, L1 (2019), doi:10.3847/2041-8213/ab0ec7 (first image of M87*)
独立核验依据 · Independent verification: 核验依据 1 CROSSREF 标识 10.3847/2041-8213/ab0ec7：First M87 Event Hor
#黑洞 #事件视界望远镜
宇航服有什么用？
What does a spacesuit do?
宇航服为宇航员提供氧气和合适的气压，同时挡住极端温度和高速飞来的微小颗粒。头盔上镀金的面罩还能过滤刺眼的阳光。
A spacesuit supplies oxygen and the right pressure while shielding an astronaut from extreme temperatures and fast-moving specks of debris. Its gold-coated visor also filters the blinding sunlight.
难度 入门 · 适合 小学低段(6-8)
CC BY 4.0 · 已核验 · Verified 2026-08-23 · 2 条独立证据
来源 · Source
Carl Sagan,《Cosmos》Random House,1980;中译《宇宙》
C. Sagan, Cosmos, Random House, 1980; Chinese ed.
独立核验依据 · Independent verification: 核验依据 2 DOUBAN ISBN 标识 9780394502946（按标识回读: Cosmos）
#宇航服 #太空行走
望远镜为什么能看清很远的星星？
Why can a telescope see faraway stars clearly?
望远镜用大镜片或大镜子收集很多光，再把光聚到一起。光变多了，远处的星星就看起来更亮更清楚。
A telescope uses a big lens or mirror to gather lots of light and bring it together. With more light collected, distant stars look brighter and sharper.
难度 入门 · 适合 幼儿(3-6)
CC BY 4.0 · 已核验 · Verified 2026-08-23 · 2 条独立证据
来源 · Source
苏宜,《天文学新概论》第5版,科学出版社
Su Yi, Introduction to Astronomy, 5th ed., Science Press
独立核验依据 · Independent verification: 核验依据 2 ISBN 9787030620477（豆瓣书目条目: 天文学新概论）
#望远镜 #观星
国际空间站上的人怎么睡觉？
How do people sleep on the International Space Station?
他们钻进固定在舱壁上的睡袋，把自己绑好，免得睡着后到处飘。站上没有真正的黑夜，很多人要戴眼罩挡光。
They zip into sleeping bags fixed to the wall and strap themselves in so they do not drift while asleep. There is no real night up there, so many wear eye masks to block the light.
难度 入门 · 适合 小学低段(6-8)
CC BY 4.0 · 已核验 · Verified 2026-10-03 · 2 条独立证据
来源 · Source
《十万个为什么》第六版天文分册,少年儿童出版社,2013
Ten Thousand Whys: Astronomy volume, 6th ed., Juvenile and Children Publishing House, 2013
独立核验依据 · Independent verification: 核验依据 1 ISBN 978-7-5324-9328-9 · 核验依据 2 ISBN 9787532493289
#国际空间站 #睡眠
宇宙大爆炸到底是怎么回事？
What was the Big Bang?
大约138亿年前，宇宙从极热极密的状态开始迅速膨胀，慢慢冷却出气体、恒星和星系。它不是炸弹那样的爆炸，而是空间本身在变大。
About 13.8 billion years ago the universe began expanding from an extremely hot, dense state and cooled into gas, stars and galaxies. It was not a bomb-like blast but space itself stretching out.
难度 入门 · 适合 小学低段(6-8)
CC BY 4.0 · 已核验 · Verified 2026-08-23 · 2 条独立证据
来源 · Source
Carl Sagan,《Cosmos》Random House,1980;中译《宇宙》
C. Sagan, Cosmos, Random House, 1980; Chinese ed.
独立核验依据 · Independent verification: 核验依据 2 DOUBAN ISBN 标识 9780394502946（按标识回读: Cosmos）
#大爆炸 #宇宙
空间站是什么？
What is a space station?
空间站是一座绕着地球飞的太空房子，宇航员住在里面做实验。它一天能绕地球十几圈。
A space station is a home in space that circles Earth while astronauts live and work inside. It loops around our planet about sixteen times a day.
难度 入门 · 适合 幼儿(3-6)
CC BY 4.0 · 已核验 · Verified 2026-08-23 · 2 条独立证据
来源 · Source
Carl Sagan,《Cosmos》Random House,1980;中译《宇宙》
C. Sagan, Cosmos, Random House, 1980; Chinese ed.
独立核验依据 · Independent verification: 核验依据 2 DOUBAN ISBN 标识 9780394502946（按标识回读: Cosmos）
#空间站 #宇航员
银河系是什么？
What is the Milky Way?
银河系是我们所在的巨大星系，由上千亿颗恒星以及大量气体和尘埃组成，外形像带旋臂的圆盘。太阳只是里面一颗很普通的恒星。
The Milky Way is the huge galaxy we live in, made of hundreds of billions of stars plus gas and dust, shaped like a disc with spiral arms. Our Sun is just one very ordinary star inside it.
难度 入门 · 适合 小学低段(6-8)
CC BY 4.0 · 已核验 · Verified 2026-08-23 · 2 条独立证据
来源 · Source
Carl Sagan,《Cosmos》Random House,1980;中译《宇宙》
C. Sagan, Cosmos, Random House, 1980; Chinese ed.
独立核验依据 · Independent verification: 核验依据 2 DOUBAN ISBN 标识 9780394502946（按标识回读: Cosmos）
#银河系 #星系
我们看到的流星其实是什么？
What are we really seeing when we spot a shooting star?
那是一小块太空里的沙石冲进空气，摩擦得发热发亮。它不是星星，只是一道亮亮的光。
It is a tiny piece of space rock or dust heating up and glowing as it rushes into our air. It is not a star at all, just a bright streak of light.
难度 入门 · 适合 幼儿(3-6)
CC BY 4.0 · 已核验 · Verified 2026-08-23 · 2 条独立证据
来源 · Source
Carl Sagan,《Cosmos》Random House,1980;中译《宇宙》
C. Sagan, Cosmos, Random House, 1980; Chinese ed.
独立核验依据 · Independent verification: 核验依据 2 DOUBAN ISBN 标识 9780394502946（按标识回读: Cosmos）
#流星 #夜空
宇宙现在还在变大吗？
Is the universe still getting bigger?
观测发现遥远星系都在远离我们，而且越远的退行得越快，说明空间本身在膨胀。上世纪末对遥远超新星的研究还表明，这种膨胀正在加速。
Distant galaxies are all moving away from us, and the farther one is the faster it recedes, which shows that space itself is expanding. Studies of faraway supernovae in the late 1990s revealed that the expansion is even speeding up.
难度 入门 · 适合 小学高段(9-12)
CC BY 4.0 · 已核验 · Verified 2026-08-23 · 2 条独立证据
来源 · Source
Carroll & Ostlie,《An Introduction to Modern Astrophysics》第2版,Cambridge University Press,2017
B. W. Carroll and D. A. Ostlie, An Introduction to Modern Astrophysics, 2nd ed., Cambridge University Press, 2017
独立核验依据 · Independent verification: 核验依据 2 ISBN 978-1-108-42216-1 (2nd ed., Cambridge Univ. Press)
#宇宙膨胀 #星系
宇航员在空间站里为什么会飘起来？
Why do astronauts float inside the space station?
空间站和里面的人一起绕着地球不停地往下掉，就像一直在下落。大家掉得一样快，就感觉不到重量，飘起来了。
The station and everyone inside are falling around Earth together, again and again. Because they fall at the same rate, they feel weightless and float.
难度 入门 · 适合 幼儿(3-6)
CC BY 4.0 · 已核验 · Verified 2026-08-23 · 2 条独立证据
来源 · Source
Carl Sagan,《Cosmos》Random House,1980;中译《宇宙》
C. Sagan, Cosmos, Random House, 1980; Chinese ed.
独立核验依据 · Independent verification: 核验依据 2 DOUBAN ISBN 标识 9780394502946（按标识回读: Cosmos）
#失重 #空间站
太空里能听到声音吗？
Can you hear sounds in space?
太空几乎是空的，没有空气帮忙把声音送过来，所以什么也听不到。宇航员要靠无线电互相说话。
Space is almost empty, and without air to carry sound there is nothing to hear. Astronauts talk to each other by radio instead.
难度 入门 · 适合 幼儿(3-6)
CC BY 4.0 · 已核验 · Verified 2026-08-23 · 2 条独立证据
来源 · Source
Carl Sagan,《Cosmos》Random House,1980;中译《宇宙》
C. Sagan, Cosmos, Random House, 1980; Chinese ed.
独立核验依据 · Independent verification: 核验依据 2 DOUBAN ISBN 标识 9780394502946（按标识回读: Cosmos）
#太空 #声音
彗星和小行星有什么不同？
How are comets different from asteroids?
小行星主要由岩石和金属构成，大多在火星与木星之间的小行星带运行。彗星含有大量冰和尘埃，多来自太阳系外围，轨道又长又扁。它们靠近太阳时，冰会升华成气体和尘埃。
Asteroids are made mainly of rock and metal and mostly circle in the belt between Mars and Jupiter. Comets contain a lot of ice and dust, usually come from the outer Solar System, and follow long stretched orbits. When they near the Sun, their ice turns straight into gas and dust.
难度 入门 · 适合 小学高段(9-12)
CC BY 4.0 · 已核验 · Verified 2026-08-23 · 2 条独立证据
来源 · Source
Carl Sagan,《Cosmos》Random House,1980;中译《宇宙》
C. Sagan, Cosmos, Random House, 1980; Chinese ed.
独立核验依据 · Independent verification: 核验依据 2 DOUBAN ISBN 标识 9780394502946（按标识回读: Cosmos）
#彗星 #小行星
宇航员在太空里怎么吃饭？
How do astronauts eat in space?
他们吃装在密封小袋里的食物，还要把袋子夹住，免得饭菜飘走。喝水要用带吸管的水袋。
They eat food from sealed pouches and clip everything down so it cannot float away. Drinks come in bags they sip through a straw.
难度 入门 · 适合 幼儿(3-6)
CC BY 4.0 · 已核验 · Verified 2026-08-23 · 2 条独立证据
来源 · Source
Carl Sagan,《Cosmos》Random House,1980;中译《宇宙》
C. Sagan, Cosmos, Random House, 1980; Chinese ed.
独立核验依据 · Independent verification: 核验依据 2 DOUBAN ISBN 标识 9780394502946（按标识回读: Cosmos）
#宇航员 #太空饮食
长期待在太空对宇航员的身体有什么影响？
How does a long stay in space affect an astronaut's body?
失重会让肌肉萎缩、骨密度下降，体液上涌还可能影响视力。宇航员因此每天要锻炼约两小时来减缓变化。太空辐射也比地面强很多，是长期任务的重要风险。
Weightlessness weakens muscles and thins bones, and fluid shifting toward the head can affect eyesight. Astronauts therefore exercise around two hours a day to slow these changes. Space radiation is also much stronger than on the ground, a major risk for long missions.
难度 入门 · 适合 小学高段(9-12)
CC BY 4.0 · 已核验 · Verified 2026-10-03 · 2 条独立证据
来源 · Source
《十万个为什么》第六版天文分册,少年儿童出版社,2013
Ten Thousand Whys: Astronomy volume, 6th ed., Juvenile and Children Publishing House, 2013
独立核验依据 · Independent verification: 核验依据 1 ISBN 978-7-5324-9328-9 · 核验依据 2 ISBN 9787532493289
#宇航员 #太空医学
太空里没有空气可以推，火箭为什么还能前进？
With no air to push against, how can a rocket move in space?
火箭向后高速喷出燃烧后的气体，按照牛顿第三定律获得同样大小的向前推力。它推的是自己喷出的物质，并不需要外面的空气。真空中还没有阻力，飞行反而更省燃料。
A rocket hurls burning gas backwards at high speed and, by Newton's third law, receives an equal push forwards. It pushes against the mass it throws out, not against outside air. In a vacuum there is no drag either, so the flight is actually more efficient.
难度 入门 · 适合 小学高段(9-12)
CC BY 4.0 · 已核验 · Verified 2026-08-23 · 2 条独立证据
来源 · Source
Carl Sagan,《Cosmos》Random House,1980;中译《宇宙》
C. Sagan, Cosmos, Random House, 1980; Chinese ed.
独立核验依据 · Independent verification: 核验依据 2 DOUBAN ISBN 标识 9780394502946（按标识回读: Cosmos）
#火箭 #反作用力