Hacker News Reader

Comment by chasd00 | Hacker News Reader

I was there a couple weeks ago. They had the Apollo control room blocked off to visitors for the rennovations so we saw a different one. The tours are kinda boring but you have to suffer one to get to the Saturn V. That thing is incredible, looking at the welds on the engines knowing they were done by hand blows me away. Also, seeing how large the turbo pumps are and imagining the LOX flowing at full tilt is scary. I get the feeling the term "control" is used very loosely once those engines are ignited.

View on HN

I've been on the tour and I didn't think it was boring. I learned a lot of past and present space exploration. I think there are 2 or 3 different tours you can choose so return trips are recommended.

I agree the Saturn V is a thing of monstrous beauty. The pictures do not do it justice. You have to stand next to it to really appreciate the magnitude of the engineering and workmanship.

Also another good NASA site to tour is the Stennis Space Center in Mississippi where they test the engines to this day. I believe it's where Wernher Von Braun spent most of his time.

I grew up in Huntsville, AL, in the 60s. Von Braun lived there and the Saturn V engines were tested there. The Stennis test stand was built for the Shuttle engines, I think. The test stand was south of Huntsville, on the banks of the Tennessee river. When they tested the F-1 we could hear it at our house on the north side of the city and it would shake the dishes in the kitchen cabinets.

Testing at Stennis started in the 60's. I know they tested at Hunstville but I thought Huntsville is where they did the Saturn V assembly.

https://www.nasa.gov/centers/stennis/pdf/428016main_FS-2010-...

Cool, I didn't know the Stennis site was that old. It looks like the F-1 was tested at several facilities. I found the link below to a Library of Congress document on the Huntsville site, which I'll have to read later.

https://www.loc.gov/resource/hhh.al1331.sheet

Actually Von Braun was probably mostly in Marshall FC but during the early engine testing they said he was in Stennis a lot.

Indeed. The engines for the modern successors to the Saturn V are/were being tested there: the BE-4 (edit: maybe the BE-3, not the -4) for Blue Origin’s New Glenn, Raptor for SpaceX’s Starship, and the SSME (as well as the whole core stage) for NASA’s SLS. We’re actually in a very exciting time for space exploration.

Merlins may have been tested at Stennis, but I believe that the Raptors are not.

The early components of Raptor were, indeed, tested at Stennis. The Raptors are now being tested in Texas. Here's an article from 2013 about the early work on Raptor: https://spacenews.com/37859spacex-could-begin-testing-methan...

Interesting, thank you!

Since a sibling mentioned Huntsville, AL, the US Space and Rocket Center now houses the Saturn V stack in the Davidson Center (built for that purpose) along with multiple other exhibits, including the Apollo 16 command module. The Space and Rocket Center is definitely worth a stop if you get a chance.

If you stop in on a Thursday between March and October, a biergarten is set up under the rocket in the evenings. Food's not the best but having sausages and beer while sitting under a Saturn V is a truly unique experience.

I went on the tours about a year ago and found them very interesting. I think you do need a good guide and group, if you sat in the back and no one asked questions I can see how it would get boring. Completely agree that the Saturn V was incredible.

To me the most impressive part of the tour was the piece of moon rock that you could literally touch. That's a chunk of rock that an astronaut picked up from the moon, across 200,000 miles of vacuum.

Thousands of engineers came together to make that achievement happen, working at the bleeding edge of what was possible 50 years ago, and here I am slacking off on Hacker News on a Monday morning instead of figuring out why this unit I keep having to power cycle won't stay online.

Really!? At the exhibits I've been to the rocks have always been kept in sealed containers. Odd question, did you happen to get to.. smell the rock? The reason I ask is that the Apollo astronauts reported that the moon dust had an aroma similar to gunpowder. Left me curious what, if any, smell a rock would have. Ostensibly it'd just smell... like a rock. But on the Earth dust also smells... like dust, not gunpowder.

Oh wow. Before submitting this just found a really interesting article on this topic. [1] While moon dust does apparently smell like gunpowder, nobody knows why. And back on Earth, the rocks return to smelling... like rocks. Very odd.

[1] - https://science.nasa.gov/science-news/science-at-nasa/2006/3...

I got to go in the big moon rock vault at JSC once and see all[1] the moon rocks. I don't remember any particular smell. Of course unlike in a museum, the ones in there we couldn't touch with bare hands or anything -- we were in bunny suits with gloves and masks and so on. And I didn't try to sniff any! Interesting article, I see that someone else agrees they don't smell like anything in the vault. :)

[1] Not literally all: aside from the small samples out for display at museums etc., about 10-15% IIRC are kept at White Sands rather than at Johnson.

Really, truly!

https://i.imgur.com/kflKLxw.jpg

That is my finger touching a piece of the moon. <shudders>.

It was just a small piece, epoxied to a polycarbonate display where it was protected from being peeled out by vandals. You can't get close enough to put your nose near it, but if you could, I suppose it would have smelled like people's fingers; it seemed to have been polished smooth by thousands of touches.

Also, I was successful in logging off HN all morning and making lives and products better by fixing the restart of this piece of industrial automation. Worn-out over-capacity SSD, apparently. Not quite a retrieval of a moon rock, but now the people putting together Mercedes A-class center consoles will be less frustrated by the heat stake machine that puts them together, and won't have to use the manual heat staker as often. Lunch is almost up - one more look at that picture, then it's back to focusing and working!

I've been to that exhibit and indeed, t is one of a few moonrock samples accessible to the public.

Being able to touch a moon rock was memorable but I never thought to smell it. My immediate inclination, to be honest, was to go off and wash my hands, considering tens of thousands of other index fingers have rubbed against it. It's probably as germy as a wal-mart shopping cart handle.

On the surface of the Moon, there is no oxygen and the rocks are bombarded by UV and other forms of radiation. That's got to lead to some interesting chemical reactions.

It probably smells like fingers, now.

One of my favorite statistics to highlight the engineering absurdity of the Apollo program is that the 'fuel pump' for each F1 operated at approximately 55,000 horsepower. And they still needed five of them to get off the pad.

The mind boggles.

How does 55,000HP compare to modern launches (e.g. SpaceX)? Have they become more efficient in harnessing less power to produce more thrust? I’m a lay person when it comes to engineering, but my assumption would be that we do not need close to 300,000HP to lift a modern shuttle up. If we do, though, it again is a magnificent task to complete.

Note that the 300k hp is for the fuel pumps, the first stage max output is roughly 160 million hp.

for those wanting to learn more, here is a Q&A from NASA and they delve into some specs on the STS-111 main engines [1]

>Darrel from Ft. Payne >How much horsepower do the shuttle's main engines produce at the time of lift off?

>NASA: The three space shuttle main engines generate the maximum equivalent of about 37 million horsepower. The fuel pump alone delivers as much as 71,000 horsepower, the oxygen pump delivers about 23,000. Just as a basis of comparison, the fuel pump alone is probably the equivalent horsepower of 28 locomotives. And with the horsepower of the oxygen pump, that's probably the equivalent of 11 more locomotives.

[1]: https://www.nasa.gov/missions/highlights/webcasts/shuttle/st...

All five engines together exceeded the electric generation capacity of France at the time.

The 55khp is for each fuel pump; the first stage needed just short of 300khp just to bring fuel from storage to the five combustion chambers. (Probably not the correct term)

Edit: ninja'd by eventualhorizon, whose comment is way more informative than mine!

(please anybody that really knows what they are talking about correct the following)

Newer engines have much higher chamber pressure so your pump demands are going to go through the roof.

For example, Elon says 100,000hp per Raptor here: https://twitter.com/elonmusk/status/1076618886932353024

But Raptor is running 300 bar chamber pressure vs 70 bar of the Rocketdyne F1. You have to pump your propellant against that with enough margin to ensure proper atomization and mixture of the liquids. Hard to say what the outlet pressure of the Raptor pumps are but it's going to be intense.

i think a key thing to remember is the manufacturing/fabrication tech. available when the F1 engines where built. Like I said, the welds on it are from a guy with a welder, no CAD/CAM, no robots, no simulation, just some guys with some machine tools, paper, and a shop.

Another thing, if you ever get the chance to visit the Johnson Space Center you can look at some of the control panels and tech. they used. Man, I wouldn't trust a trip to Home Depot and back using that tech and they said, "screw it we're riding this to the moon".

edit: there's a youtube out there of a project to rebuild part of an F1 engine. I think they conclude that a complete F1 can't be built today because a lot of the hand fitting and "tricks of the trade" were never written and down and modern fabrication techniques can't replicate the shape of certain F1 parts. ...something like that

there is a youtube channel trying to rebuild the apollo launch computer.

Very nerdy. The memory is rings of magnets. It is pretty fun though:

https://www.youtube.com/watch?v=2KSahAoOLdU

Also, that Saturn V in Houston was flight ready. It's not a model, they separated the stages a little bit so you could see inside, but that is as real as it gets. I could have stayed in there all day.

I remember visiting Marshall Space Flight Center in Huntsville, AL as a Cub Scout and walking up to the Saturn V. It was laying on its side, and I was a short kid, but the size of just one those engines blew me away. I’ll never forget that sense of wonder and amazement.

I saw a Saturn V at Kennedy. Before that, I had absolutely no concept of the size of those rockets. It is absolutely epic in scale. It is in my view one of the greatest wonders of the modern world.

The Level 9 tour is anything but boring, though I can see the larger tours being less interesting when you don't get to look in the Soyuz trainer or go to the National Buoyancy Lab. However, you don't need to take a tour our pay anything to go to the rocket park. It's free and open to the public, you can just tell guard at the main gate that's where you're going and they'll let you through.

Reply on news.ycombinator.com