Comment by KaiserPro

Comment by KaiserPro 3 days ago

3 replies

1) ISS is about 30 years old. It's hardly the state of the art in solar technology.

Domestic solar panels are heavy, and dont need to deal with hypersonic sand blasting. even at that height, you are in shadow every 90 minutes.

> 3) The article complains about lack of bandwidth. Star Link serves millions of customers with high speed, low latency internet via thousands of satellites.

Right. First power and heat are a massive pain to deal with. You need megawatts to run a datacentre. A full rack of GPUs (48u, 96 GPUs) is around 40-70kw. It also weighs a literal ton.

You also need to be able to power that in the time when you are in darkness. BUT! when you are zooming around the earth every 90 minutes, you can't maintain a low latency connection, because the distance between you and the datacentre.

That means geostationary, as that solves most of your power issues, but now you have latency and bandwidth issues. (oh and power, inverse square law and bandwidth are related)

> 5) Learning effects

Great, but it gets us nothing.

mr_toad 3 days ago

> even at that height, you are in shadow every 90 minutes.

There are orbits that stay in permanent sunlight, even in LEO.

  • shagie 3 days ago

    There is one. It is the sun synchronous dawn/dusk orbit.

    https://en.wikipedia.org/wiki/Sun-synchronous_orbit

    > Special cases of the Sun-synchronous orbit are the noon/midnight orbit, where the local mean solar time of passage for equatorial latitudes is around noon or midnight, and the dawn/dusk orbit, where the local mean solar time of passage for equatorial latitudes is around sunrise or sunset, so that the satellite rides the terminator between day and night.

    The dawn dusk orbit is in constant sunlight. The noon-midnight orbit isn't.

    Those orbits (and their corresponding constellations) lack 100% availability for a ground station.

    Furthermore, a polar orbit launch is quite a bit more expensive since it requires a significant change in inclination.

  • KaiserPro 3 days ago

    yup, and that means that you only have low latency once a day.