How don’t we see huge satellite shaped shadows cast on the earth? Wouldn’t satellites be between the sun and the earth meaning that they’d cast a shadow on us?
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Two things,
– Satellites are very very small compared to celestial objects like the Earth, or even the Moon
– Light has a property called diffraction (made possible because light behaves like a wave). What this means is that light waves tend to bend inwards around the edges of objects
So when satellites come between the Sun and the Earth, their small size and diffraction of light means that their shadow is cast for only a short distance, thus not reaching the Earth’s surface
For the same reason that you don’t see a huge bee-shaped shadow on the wall when a bee flies past your window – it only blocked a tiny part of the window at a time, and therefore only a tiny part of the light. [This](https://petapixel.com/2015/09/09/a-composite-photo-of-the-international-space-station-transiting-the-sun/) is what it looks like when the ISS passes between us and the Sun, and other satellites are much smaller than that.
Satellites are relatively close to the surface compared to the source of light (sun) so the shadows would be just a little larger than the actual size of them. Diffraction makes these shadows completely imperceptible.
I live close to an airport.
If a BIG plane flies above my house, going at 300-500kmk, I can see a quick shadow passing on me, very very quick, almost unnoticeable.
A satellite is very small, less than a meter, traveling at 10000 km/h and more. Even if you are there and hit by the shadow, your eyes would not have the time to see it.
Last, air refracts the light, so the further away an object is the more blurry is it’s shadow, I bet that the satellite is way too far to cast a observable shadow anyway.
The Sun is larger than a satellite and, more importantly, it has a larger visible size. That is, if a satellite (even ISS) passed right before the Sun, it would look like a tiny speck on its disk, since satellites fly at altitudes over 100 km. So a satellite simply cannot block the Sun completely, meaning no shadow. Or, more precisely, the satellite’s shadow only goes for a few kilometers below it, down to a point from which it becomes small enough to not be able to block the Sun completely.
Try holding a paperclip a couple of feet away from a lamp and see if it cast a shadow in your room.
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