You are viewing a single thread.
View all comments View context
77 points

fun fact, that would make the transmission slower.

According to wikipedia cat5 cable has a propagation delay of 5.30 ns/m, which works out to about 62% of the speed of light. While radio waves propagate at the speed of light.

permalink
report
parent
reply
24 points
*

Yeah, the reason ethernet is generally faster compared with wifi is mainly due to interference from physical objects between the device and the transmitter. Not as much an issue when you’re issuing commands into the vacuum of space from large, high-powered antennas.

permalink
report
parent
reply
5 points

hehe, imagine a tcp handshake with voyager

permalink
report
parent
reply
1 point

Not as much an issue when you’re issuing commands into the vacuum of space

permalink
report
parent
reply
6 points
*

Radio waves always propagate at the speed of light, it’s just that the effective speed of light in copper and glass fibre is lower than that in air/vacuum.

This means that if you have long cables at some distance you’ll get a lower delay by using low earth orbit satellites like Starlink. Assuming a total distance via satellite of 1000km and the effective speed of light in glass fibre to be 2/3 c, cables over 667km will have a higher delay than the satellite.

permalink
report
parent
reply
1 point

Some fiber-optic cables are faster than others, because they’re full of air. Hollow-core fibers have a large central cutout and/or a close hexagonal packing of smaller glass tubes. The latter are technically a “photonic crystal.”

permalink
report
parent
reply
1 point

Speed of light in fiberoptic cable is slower than c for a different reason. The light is in something close to vacuum, signals travel slower than c because the light doesn’t follow a straight path, it zig zags bouncing off the walls.

A radio wave or laser in reasonable vacuum (in orbit for example) will be lower latency than a signal on a fiber link the same length

I’m expecting lower ping via starlink than fiber once starlink has laser links between satellites

permalink
report
parent
reply

Science Memes

!science_memes@mander.xyz

Create post

Welcome to c/science_memes @ Mander.xyz!

A place for majestic STEMLORD peacocking, as well as memes about the realities of working in a lab.



Rules

  1. Don’t throw mud. Behave like an intellectual and remember the human.
  2. Keep it rooted (on topic).
  3. No spam.
  4. Infographics welcome, get schooled.

This is a science community. We use the Dawkins definition of meme.



Research Committee

Other Mander Communities

Science and Research

Biology and Life Sciences

Physical Sciences

Humanities and Social Sciences

Practical and Applied Sciences

Memes

Miscellaneous

Community stats

  • 12K

    Monthly active users

  • 2.8K

    Posts

  • 41K

    Comments