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You can't have 24hour sunlight AND low altitude, low-latency orbits

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Re: You can't have 24hour sunlight AND low altitude, low-latency orbits

#2
> You can't have 24hour sunlight AND low altitude, low-latency orbits.

The key issue is "low-latency". The DCs in space are about getting ~10x the energy/day compared to ground DCs. Moving from 300km to 1400km doesn't increase latency that much since those DCs aren't meant to have realtime connections to users. I think the criticism is confusing something like Starlink which gets low latency by having a ton of routers that are only ~300km away from the user with these DCs which will by design have to transmit from polar orbit to wherever the ground control is. 300km or 1400km won't be a big deal compared to the tramission time from polar orbit to the urban or tech hubs.

Gemini's math about median RTT from these DCs to a random spot on Earth suggests the altitude change only adds 15ms of latency:

  The median surface distance between any two arbitrary points on Earth is 90deg along the globe, or 10,008km. Scaled up to the respective orbital radii (6,671 km vs. 7,971km), the median one-way vacuum ISL path length is ~10,480km at 300 km altitude and ~12,520km at 1,600 km altitude...When factoring in realistic ground-to-space uplinks/downlinks, atmospheric delay, and optical switching overhead, the median global RTT increases to approximately 85-100ms for a 300 km constellation compared to 100-115ms for a 1,600 km constellation.

Re: You can't have 24hour sunlight AND low altitude, low-latency orbits

#3
This was never an issue. Space-based data centers in SSO will connect to the internet via Starlink's laser network.

SSO data centers were never meant for low-latency applications. The intent is to perform non-time sensitive workloads, such as model training or batched inference.

Re: You can't have 24hour sunlight AND low altitude, low-latency orbits

#4
post #2

> You can't have 24hour sunlight AND low altitude, low-latency orbits. The key issue is "low-latency". The DCs in space are about getting ~10x the energy/day compared to ground DCs. Moving from 300km to 1400km doesn't increase latency that much since those DCs aren't meant to have realtime connections to users. I think the criticism is confusing something like Starlink which gets low latency by having a ton of router…

Starlink sats have been described as having a low Kessler Syndrome risk due to low altitudes. What happens to that risk at 1400km as the rings of DCs scale up?