4 ms·

I'm amazed that the latency appears so low. I used satellite broadband for years here in very rural England, latency was more like 1000ms!

tigershark 6y ago
LEO vs GEO, that is the main advantage of starlink
octoberfranklin 6y ago
Geosynchronous (35,786km from surface) versus VLEO (550km from surface). Basically the difference in altitude between your satellite and these satellites is almost three times the earth's diameter.
Aldipower 6y ago
If you take the US to Europe round-trip, the latency is even faster then the cable bound connection, because the light in vacuum (space) travels around 1/3 faster then in fiber.
- FrojoS 6y ago
  Only once they have inter satellite communication working.
- bifrost 6y ago
  > because the light in vacuum (space) travels around 1/3 faster then in fiber Pretty sure the speed of light is a constant... You may be confusing the latency of the network framers/etc.
  - Aldipower 6y ago
    So, you are wrong. The speed of light is not constant. :) The speed of light depends on the medium, where the reference (or max speed) is the speed of light in vacuum. The speed of light in a diamond is only half of the speed in vacuum for example! This is why the latency of the low orbit satellites is lower then the cable bound connection.
    - anuila 6y ago
      IANAS but from what I understand, the speed is constant, but it appears to travel more slowly due to the atoms found along the way, which absorb and reemit the photon. In the case of the fibers, the light just bounces on the walls of the tube, effectively lengthening the distance it has to travel. It's like saying that I did not drive a 50 mph simply because I took a longer detour: I still drove 50 mph, but I did not go in a straight line.
      - foxyv 6y ago
        > In the case of the fibers, the light just bounces on the walls of the tube, effectively lengthening the distance it has to travel. This is incorrect, the reduced speed of light is due to the properties of the material through which the light is traveling. The material has in fact changed the speed of light. The wave equation of light is dictated by the permittivity and permeability of the material through which it propagates. This is just a property of electromagnetic waves. Only the speed of light in a vacuum is a constant. Or more accurately, the permeability and permittivity of a vacuum.
      - fomine3 6y ago
        Also fun: low latency fiber is made in space. https://upward.issnationallab.org/the-race-to-manufacture-zblan/ https://upward.issnationallab.org/the-race-to-manufacture-zb...
  - foxyv 6y ago
    The index of refraction of materials is caused by differences of the speed of light in those materials. However, according to the theory of relativity, the speed of light in a _vacuum_ is constant in all reference frames. There is a neat web page where you can see the speed of light in different materials: https://micro.magnet.fsu.edu/primer/java/speedoflight/index.html#:~:text=Light%20travels%20at%20approximately%20300%2C000,(refractive%20index%20of%201.5) https://micro.magnet.fsu.edu/primer/java/speedoflight/index.....

tigershark 6y ago

LEO vs GEO, that is the main advantage of starlink

octoberfranklin 6y ago

Geosynchronous (35,786km from surface) versus VLEO (550km from surface). Basically the difference in altitude between your satellite and these satellites is almost three times the earth's diameter.

Aldipower 6y ago

If you take the US to Europe round-trip, the latency is even faster then the cable bound connection, because the light in vacuum (space) travels around 1/3 faster then in fiber.

FrojoS 6y ago
Only once they have inter satellite communication working.
bifrost 6y ago
> because the light in vacuum (space) travels around 1/3 faster then in fiber Pretty sure the speed of light is a constant... You may be confusing the latency of the network framers/etc.
- Aldipower 6y ago
  So, you are wrong. The speed of light is not constant. :) The speed of light depends on the medium, where the reference (or max speed) is the speed of light in vacuum. The speed of light in a diamond is only half of the speed in vacuum for example! This is why the latency of the low orbit satellites is lower then the cable bound connection.
  - anuila 6y ago
    IANAS but from what I understand, the speed is constant, but it appears to travel more slowly due to the atoms found along the way, which absorb and reemit the photon. In the case of the fibers, the light just bounces on the walls of the tube, effectively lengthening the distance it has to travel. It's like saying that I did not drive a 50 mph simply because I took a longer detour: I still drove 50 mph, but I did not go in a straight line.
    - foxyv 6y ago
      > In the case of the fibers, the light just bounces on the walls of the tube, effectively lengthening the distance it has to travel. This is incorrect, the reduced speed of light is due to the properties of the material through which the light is traveling. The material has in fact changed the speed of light. The wave equation of light is dictated by the permittivity and permeability of the material through which it propagates. This is just a property of electromagnetic waves. Only the speed of light in a vacuum is a constant. Or more accurately, the permeability and permittivity of a vacuum.
    - fomine3 6y ago
      Also fun: low latency fiber is made in space. https://upward.issnationallab.org/the-race-to-manufacture-zblan/ https://upward.issnationallab.org/the-race-to-manufacture-zb...
- foxyv 6y ago
  The index of refraction of materials is caused by differences of the speed of light in those materials. However, according to the theory of relativity, the speed of light in a _vacuum_ is constant in all reference frames. There is a neat web page where you can see the speed of light in different materials: https://micro.magnet.fsu.edu/primer/java/speedoflight/index.html#:~:text=Light%20travels%20at%20approximately%20300%2C000,(refractive%20index%20of%201.5) https://micro.magnet.fsu.edu/primer/java/speedoflight/index.....