Slop.

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For posting all the anonymous reactionary bullshit that you can't post anywhere else.

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104

Anticommunist space nerds CRYING and SHIDDING themselves over a meme I made seven years ago (hexbear.net)

submitted 3 days ago* (last edited 3 days ago) by TankieTanuki@hexbear.net to c/slop@hexbear.net

83 comments fedilink hide all child comments

Slop? How dare you. This was a hand-crafted artisanal meme that took me a whole night in GIMP to make! meow-cactus

https://xcancel.com/mightbejell0/status/2042447337201483991

[CW: racism, ableism, homophobia, slurs]

https://xcancel.com/TankieTanuki/status/2042395973822136721

Cowbee's Law: Effective agitprop will make you enemies.

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[–] TankieTanuki@hexbear.net 5 points 2 days ago* (last edited 2 days ago) (1 children)

The Surveyor 6 had a different type of engine. The Apollo Lunar Module's used hypergolic fuel, meaning it didn't require an ignition source. It also produced 23 times as much thrust as the Surveyor 6.

Not only was the Apollo 11 mission the first time that that particular engine model had ever been fired on the Moon; it was the very first time that that particular unit had been fired, ever. Because it had to be rebuilt after each use, it was impossible to test it on the ground before the mission as a quality control measure.

Incredibly gutsy.

[–] buckykat@hexbear.net 3 points 2 days ago (1 children)

it was the very first time that that particular unit had been fired, ever.

This is true of pretty much every rocket engine ever fired (including the space shuttle main engines which also had to be almost completely rebuilt after each use) except a few recent reusable first stages.

[–] TankieTanuki@hexbear.net 1 points 2 days ago (2 children)

I'm not sure that's true. You can find videos of NASA's hot fire tests. This article says they test the "flight version" of the RS-25, which sounds like it's the same unit to be used in the mission. Hypergolic propellants are too corrosive to do similar testing.

Slop machine [DeepSeek] output

Prompt: Can rocket engines be test fired before a mission?

Yes, rocket engines are routinely test-fired before a mission. This process, often called a static fire test or hot fire test, involves igniting the engine while the rocket remains secured to a test stand or launch pad.

NASA conducts full-duration static fires for engines like the RS-25 (Space Launch System) and previously for Space Shuttle Main Engines. SpaceX performs static fires of Falcon 9 and Starship engines before nearly every launch. Blue Origin, Rocket Lab, and others follow similar practices.

However, not every individual engine on a production line is test-fired if the design is well-proven and quality control is rigorous. But for crewed missions, new engine designs, or engines that have been refurbished, test firing is standard. Also, some solid rocket motors cannot be test-fired once fully assembled (they are test-fired in segments or via subscale models, because once lit they burn completely).

Prompt: Was this also true of the Apollo Lunar Module's ascent engines?

Yes, but with a critical nuance: while the ascent engine could not be static test-fired on the ground after being installed on a flight-ready Lunar Module (LM), it was certified through an exhaustive program of separate component testing and a single crucial in-flight test.

Ground Test-Firing: Not performed on a completed, flight-configured LM. The hypergolic propellants were too corrosive and would damage the engine if fired more than once.

Reason: The engine used hypergolic propellants (Aerozine 50 fuel / nitrogen tetroxide oxidizer) that ignite on contact, ensuring reliability but causing internal wear.

The ascent engine was unique because it was the only major Apollo system without a physical backup. If it failed on the Moon, the astronauts would be stranded with no rescue option. Because of this, the design prioritized absolute reliability over testability. The use of hypergolic propellants meant the engine had no ignition system to fail, but this same hypergolic chemistry meant the engine would destroy itself if fired more than once on the ground.

[–] buckykat@hexbear.net 1 points 2 days ago

The RS-25 is the space shuttle main engine, and a major reason the space shuttle never achieved its planned flight cadence was that the engines required a significant amount of rebuilding between each flight. The way they were used on the shuttle was to light them with the launch platform holding the shuttle down and make sure they were firing well before lighting off the SRBs (which cannot be shut down once lit) and releasing the launch clamps.

The Falcon (and to some limited degree Starship) are most of what I was referring to with "a few recent reusable first stages"

[–] HexReplyBot@hexbear.net 1 points 2 days ago* (last edited 2 days ago)

I found a YouTube link in your comment. Here are links to the same video on alternative frontends that protect your privacy: