# Tag Info

### What is the maximum distance between two satellites orbiting at 400 km that would still allow them to communicate with each other using radio waves?

Imagine a circle (the circumference of the Earth) and a triangle with the angle points being the locations of the satellites and the centre of the Earth. (the centre of the circle) You can divide that ...
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### What is the maximum distance between two satellites orbiting at 400 km that would still allow them to communicate with each other using radio waves?

Probably not quite what you're looking for, but two satellites on opposite sides of Earth, 13542 km apart, can still stay in almost-uninterrupted contact via EME communications (bouncing the signal ...

### What is the maximum distance between two satellites orbiting at 400 km that would still allow them to communicate with each other using radio waves?

For line-of-sight communication it's not longer than $2\sqrt{ (6371+400)^2 - (6371)^2} = 4585$. Or $2\cos^{-1}\left(\frac{6371}{6371+400}\right)$ = 40 degrees, so 9 satellites at least.
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Accepted

### What is the maximum distance between two satellites orbiting at 400 km that would still allow them to communicate with each other using radio waves?

If, for example, you have only 2 satellites separated by half the distance (i.e., 21, 271 km), will they be able to communicate with each other? I guess not because Earth would be in the way. ...
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### Were Hasselblad cameras used in space after the Apollo mission?

Yes, they were used on the space shuttle inside the cabin. So this iconic image of Bruce McCandless II was taken with a Hasselblad Camera from inside the cabin of the Orbiter. I could not find any ...
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### Do astronauts aboard the International Space Station (ISS) actually use their legs?

It is worth noting that in the 2021 recruitment process, ESA is also looking for astronauts with physical disabilities, including: Persons who have a lower limb deficiency (e.g. due to amputation or ...
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1 vote

### What is the maximum distance between two satellites orbiting at 400 km that would still allow them to communicate with each other using radio waves?

This depends on the wavelength. While short waves spread more like a light, long waves bend over horizon and can cover distances in excess of 17,000 km even from the surface of the Earth. This is more ...
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1 vote

### Why does the ISS have to be destroyed?

Don't forget about the more "mundane" reasons, like legal ones. ISS is a large structure that has a lot of potential liability attached to it, and nobody is going to invest money on ...
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