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SpaceX Facilities and Fleets / Re: SpaceX Texas Massey site Discussion and Updates

« Last post by catdlr on Today at 05:05 am »

Cross-Post

https://twitter.com/efraser77/status/2013839446148329505

Erik Fraser
@efraser77
It appears the B18.3 test tank buckled below the common dome level during crush testing at the Masseys test site this evening. It's currently unclear whether this was intentional or not. Watch till the end for a zoomed in view.

🎥: http://nsf.live/starbase
@NASASpaceflight

https://twitter.com/colleenliedtke/status/2013849995024142382

Colleen
@colleenliedtke
B18.3 test tank buckled below the common dome level during crush testing at the Masseys test site this evening.

📷:
@NASASpaceflight

2

SpaceX Starship Program / Re: SpaceX/Elon Making 10,000 Starships a Year?

« Last post by DanClemmensen on Today at 05:05 am »

SSO is not your average LEO, it doesn't look like starship will be able to launch any useful payload to SSO any time soon, 200t payload definitely never, that's just not physically possible with this architecture. Orbital refueling doesn't help here much, probably something like launch smallish payload to very low not exactly SSO then refuel, raise and dogleg to target SSO, very inefficient.

I don't completely trust my model on this, but I think it's moderately accurate on computing doglegs.  (It assumes that all delta-v to 200km x 200km is applied at the dogleg, which obviously isn't true, but it is past most of the gravity drag for the launch.)  If you can put 200t into 200km x 200km x 28.5º from the Cape, then you should be able to put 101t into the SSO that's 567 x 567 x 97.7º, using the Cuban Dogleg.  If you launch from Vandenberg, you can put 119t into the same orbit, with no dogleg.

That sounds pretty useful to me.

Presumably, if you can dogleg 101t into that orbit you can dogleg more mass into a lower orbit in that plane, and dogleg a tanker with that same mass of propellant to meet it there so it can boost to a higher orbit and then return from it. I'm not sure why the customer wants this big satellite in that orbit.

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SpaceX Starship Program / Re: SpaceX Starship/Super Heavy Engineering General Thread 5

« Last post by catdlr on Today at 05:04 am »

https://twitter.com/efraser77/status/2013839446148329505

Erik Fraser
@efraser77
It appears the B18.3 test tank buckled below the common dome level during crush testing at the Masseys test site this evening. It's currently unclear whether this was intentional or not. Watch till the end for a zoomed in view.

🎥: http://nsf.live/starbase
@NASASpaceflight

https://twitter.com/colleenliedtke/status/2013849995024142382

Colleen
@colleenliedtke
B18.3 test tank buckled below the common dome level during crush testing at the Masseys test site this evening.

📷:
@NASASpaceflight

4

SpaceX Starship Program / Re: StarCycler: A Starship-Based Artificial Gravity Station

« Last post by mikelepage on Today at 04:54 am »

Quoting myself from the prop-transfer thread.

For a while I have been thinking that the 4 probe-drogue setup is purely a mechanical linkage such that the two ships' QD interfaces can be brought together for prop transfer<snip>

Also, at some point it will probably be useful to dock two starships together in a "69" position ...

Back when we thought SpaceX was planning "tail to tail" propellant transfer, I was a fan of using that configuration to test rotational gravity concepts, but we've since realised that wouldn't work anyway... because of the stability issue. We want the moment of inertia around our preferred axis of rotation to be a factor of at least 1.2x that of the intermediate axis, to ensure stable rotation (can't find a source for that, but it seems a good rule of thumb).

I still think rotational gravity concepts should try to stick close to existing technologies, and so I offer this configuration - call it the "offset inverted config" if you prefer  - requiring a beefing up of the probe docking system SpaceX is already building (and a rearrangement of the crew cabin to take advantage).

Approximating Starship to a 9m diameter 50m cylinder, I find that the axis of rotation in this setup has to be around 2m beyond the outer rim of Starship in order for the moment of inertia around this axis of rotation to be >1.2x that of the intermediate axis. This achieves stable end over end rotation, with the crew cabin(s) being at radii of 15 to 35m.

Also as a heads up to those who haven't followed the centrifugal gravity thread closely, space stations have to get pretty substantial before it's worth attempting any counter-rotating / flywheel shenanigans instead of just using thrusters to spin up/ spin down. See my attached spreadsheet to have a play with the numbers. In this current setup - to get 22-50% of Earth gravity at 3.6 rpm - you need about 1.5 tons of prop per spin-up or spin-down if using the nose thrusters.

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SpaceX Starship Program / Re: SpaceX/Elon Making 10,000 Starships a Year?

« Last post by TheRadicalModerate on Today at 04:32 am »

SSO is not your average LEO, it doesn't look like starship will be able to launch any useful payload to SSO any time soon, 200t payload definitely never, that's just not physically possible with this architecture. Orbital refueling doesn't help here much, probably something like launch smallish payload to very low not exactly SSO then refuel, raise and dogleg to target SSO, very inefficient.

I don't completely trust my model on this, but I think it's moderately accurate on computing doglegs.  (It assumes that all delta-v to 200km x 200km is applied at the dogleg, which obviously isn't true, but it is past most of the gravity drag for the launch.)  If you can put 200t into 200km x 200km x 28.5º from the Cape, then you should be able to put 101t into the SSO that's 567 x 567 x 97.7º, using the Cuban Dogleg.  If you launch from Vandenberg, you can put 119t into the same orbit, with no dogleg.

That sounds pretty useful to me.

6

Historical Spaceflight / Re: The Apollo Lunar Module Engineering

« Last post by catdlr on Today at 03:55 am »

The Lunar Module Descent Engine: Why Throttleability Nearly Broke Apollo

Jan 20, 2026 
The Lunar Module descent engine was unlike any rocket engine flown before. It had to throttle deeply, remain stable at low thrust, hover near the lunar surface, and respond to both guidance commands and crew input in real time. NASA documents show that this requirement pushed combustion stability, pressurization, valve control, and system integration to their limits. In this video, we examine how throttleability shaped the Lunar Module descent engine, the technical problems it caused, and why landing on the Moon depended on an engine that could behave more like a control system than a rocket motor. Based entirely on original NASA technical reports and Apollo experience documents.

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SpaceX Starship Program / Re: SpaceX/Elon Making 10,000 Starships a Year?

« Last post by Vultur on Today at 03:16 am »

SSO is not your average LEO, it doesn't look like starship will be able to launch any useful payload to SSO any time soon, 200t payload definitely never, that's just not physically possible with this architecture. Orbital refueling doesn't help here much, probably something like launch smallish payload to very low not exactly SSO then refuel, raise and dogleg to target SSO, very inefficient.

If you start in a "not exactly SSO" can the data center satellites use electric propulsion to reach the final SSO?

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Blue Origin / Re: New Glenn : Blue Moon MK1 Pathfinder : NET 2026

« Last post by Vultur on Today at 03:10 am »

https://twitter.com/blueorigin/status/2013686788167000239

Blue Moon MK1 left for the port today ahead of shipment to Houston.
 
Introducing Endurance. Named for Ernest Shackleton’s legendary ship that journeyed to Earth’s South Pole, MK1 honors resilience under pressure. That same spirit of perseverance guides our mission to the lunar South Pole.

I love the name.

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Indian Launchers / Re: PSLV-XL C63 : TDS-01 : FLP : NET Q1 2026

« Last post by AndrewM on Today at 02:47 am »

This mission will likely be delayed due to the EOS-N1 failure.

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Chinese Launchers / Re: Hong Kong / Macau astronauts - Shenzhou 22/23?

« Last post by AndrewM on Today at 02:36 am »

Wasn't on SZ-22.