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by agar 723 days ago
Interesting that they chose an 8 meter diameter, probably assuming a launch on the 9-meter Starship as Blue Origin's New Glenn is only 7m diameter. It would be interesting to see a weight projection for a completed module to see how well it fits within Starship's planned capacity of between 100 to 200 tons to orbit.

A 50cm (max) gap between the module's outer edge and Starship's inner edge does not seem like much room for support or deployment infrastructure in the launch vehicle, and would also require bay doors that fully open - and maybe a robot arm to safely deploy.

I haven't seen any reference to explicit collaboration between Gravitics and SpaceX. Maybe it's still too early, but I would hope the two have open lines of communication to avoid expensive redesigns later on.

3 comments

The starship users guide[1] indicates that an 8 meter diameter payload is the maximum that can be accommodated.

[1] https://www.spacex.com/media/starship_users_guide_v1.pdf

Yeah, that makes sense and they are likely communicating. The dimension is often used approximately to know what class of launch vehicle it is fitting in. For the standard existing rockets we will say things like "this spacecraft fits in a 5m fairing", but the actual static payload envelope is 4.82m or something. So don't take it as a precise measurement.
They are working on 4m and 6M versions as well and yeah, the 8m is for Starship.

https://www.gravitics.com/news/nasa-saa-verification

China is developing a 10m diameter rocket that looks heavily inspired by Starship; methalox engines, stainless steel construction, possibly partly/fully reusable

But yeah I can't imagine this going on any other rocket. At some point in the future there will be a market for habitable volume. Right now habitable volume is built like an RV, a mostly self-contained singular unit, but in the future modular construction might look like big rigid bubbles of air with windows, and every couple of units you have a "mechanical" area for hvac, power, water etc, similar to how high-rise buildings are designed.