# Artemis launch



## Phishfry (Aug 31, 2022)

Quite a rocket. I hope it makes it to the moon.








						Scrubbed Artemis 1 Launch Prompts Concerns About Unfinished Rehearsals
					

NASA is under tremendous pressure to launch its new megarocket—and it shows.




					gizmodo.com


----------



## Phishfry (Aug 31, 2022)

I thought SpaceX would be zooming into space once they got FAA approval.
Seems like they should be doing more than playing with the chopsticks.
Rapid iteration of nothing launch-able so far.
Stainless ain't cheap and I wonder how many sections have been scrapped (lots).

The thermal tiles application looks sketchy. How many times has the skylift bumped into the rocket?
Just those huge shackles for lifting the upper stage should have a thick rubberized finish. I don't get it.
COTS as much as possible for spacecraft equipment.
Quite the opposite of Artemis


----------



## Jose (Aug 31, 2022)

You reminded me I meant to update my sig after Monday's scrub.


----------



## Phishfry (Aug 31, 2022)

Take the $20B writedown and contract out the work.
Lead or step aside.
I don't feel like launching a disposable rocket this day and age should be acceptable.
SpaceX has prevented how much space and ocean trash?
It has been replaced by a large number of satellites they are launching. That is a future problem.


----------



## Crivens (Aug 31, 2022)

Word goes that SpaceX shall drag their feet untill Artemis gut off. Might be true, a lot of well connected PHBs are loosing face should SpaceX be so much faster and cheaper.


----------



## jbo (Aug 31, 2022)

Phishfry said:


> I don't feel like launching a disposable rocket this day and age should be acceptable.


A lot of parts of this rocket already flew before and have been sitting in warehouses for a while. This rocket is basically an engineering result of "let's use what we already have".
Also, lets not forget that rockets/booster recovery has been done before SpaceX. What changed over the decades is the fact that we now have the engineering tools, capabilities & know-how to produce parts that can _safely_ fly again. Recovery is not necessarily the hard part. But ensuring that after recovery you can safely light the candle again is a whole different story.


----------



## Jose (Aug 31, 2022)

Crivens said:


> Might be true, a lot of well connected PHBs are loosing face should SpaceX be so much faster and cheaper.


That ship has sailed. There are many writeups of how much cheaper and faster you could do what the SLS is supposedly going to do with Falcon Heavies.


----------



## Phishfry (Aug 31, 2022)

I must say that SpaceX launch website is very detailed. The exact trajectory and times overhead.

I still can't find that for Artemis. One graphic has it heading straight east from the Cape. 
Usually Falcon9 heads up the coast enough for nite viewing.



jbodenmann said:


> A lot of parts of this rocket already flew before and have been sitting in warehouses for a while. This rocket is basically an engineering result of "let's use what we already have".


Yes the Solid Rocket Boosters from the Shuttle program. 
How unimpressive when SpaceX is using cryo chilled gases.

SpaceX has two turbo pumps per engine(Methane and LOX).
That must be a challenging rotating assembly to build.
They have to pre-chill the engine before light off. Think of the temperature differences that must produce.
From 60Kelvin to 1000c in mere seconds. That is some good engineering.

I am impressed with how well SpaceX's Starship 304L tanks handle Super Chilled Fluids.
Multiple cycles must be hard on the seems. Looked like they use sub-arc robot welders.

One thing that flummoxes me is why don't they have a recovery system for cryo gasses that bleed off.
You know they are going to vent in Texas heat, why don't they trap it instead of letting it blow off.


----------



## Jose (Aug 31, 2022)

I think I read somewhere that they do recirculate the majority of the cryo fluids. Some venting is apparently unavoidable. Musk had plans to build a liquid Oxygen distillation plant at Boca Chica, but they got shelved during the environmental review.


----------



## Crivens (Aug 31, 2022)

I have the live feed from BC on my workstation open. The Boss gehts irritated 
Esp. when some F22 jokys think they need to pose around


----------



## Phishfry (Sep 3, 2022)

Scrubbed again. Just tow it off the pad and put it in storage. The space industrial complex won't allow that.
They have Artemis2 in the wings. Must...keep...pork...flowing.

All that crap in the media about Florida traffic jams due to visitors for launch... Over 100000 to visit..
Hah.


----------



## Phishfry (Sep 7, 2022)

Pretty good article on the Hydrogen problems.








						Why Hydrogen Leaks Continue to Be a Major Headache for NASA Launches
					

A hydrogen leak prevented the launch of NASA’s SLS rocket this Saturday, in what is a troubling yet highly predictable development.




					gizmodo.com
				



8" quick disconnect line of liquid hydrogen. I wonder what the boot seal is made of.

The fact that the rocket shrinks 6" in height is amazing to me. I would have expected it to grow with tank filling.



> That NASA *has yet to fully fuel the first and second stages *and get deep into the countdown is a genuine cause for concern.



That is the 50 billion dollar understatement.


----------



## Crivens (Sep 7, 2022)

Just look at the boiling point of hydrogen at sea level. These tanks either need to be very robust or very well insulated. And when they reach some height, the boiling point drops. There is a reason SpaceX went with methane and roscosmos with kerosine. Using hydrogene is tricky.


----------



## Phishfry (Nov 14, 2022)

The latest news of .2" Thick RTV Silicone fell off really had me laughing.
Was just a gap filler....


			Engineers assessing hurricane-damaged insulation before Artemis launch Wednesday – Spaceflight Now
		


I would suggest some 5200 Marine Adhesive. This stuff holds like gorilla snot.


			https://www.3m.com/3M/en_US/p/d/b40066983/
		

I don't know if it would hold up to all that of shrinkage though.

Just the fact that the fit was so poor that they needed to fill an indentation is telling.
That is stuff we do at shipyards. Not on rockets.


----------



## Jose (Nov 16, 2022)

Aaand the thing has sprung a leak - again!   

Edit: OMG, they're sending some dudes with wrenches to tighten some nuts on the thing while it's fully fueled! I hope this doesn't end badly.


----------



## K5KGT (Nov 16, 2022)

I bet he wears his grounding strap.


----------



## Jose (Nov 16, 2022)

Now they've lost a network switch... I shit you not.


----------



## Jose (Nov 16, 2022)

More loose RTV!


----------



## Jose (Nov 16, 2022)

It launched! Inconceivable!


----------



## Crivens (Nov 16, 2022)

This whole Carly Foxtrot is so bad the earth repelled it... thats why it flies.


----------



## SirDice (Nov 16, 2022)

K5KGT said:


> I bet he wears his grounding strap.


And a pair of brown trousers, just in case.


----------



## Crivens (Nov 16, 2022)

I just hope they have special equipment and tools for this, like bronze hammers and wrenches which do not create sparks when dropped or hitting steel. And I'd be more concerned with freeze damage. Having liquid hydrogen splash on your boots will ruin your day.


----------



## Phishfry (Nov 16, 2022)

Crivens said:


> like bronze hammers and wrenches


Too soft. Beryllium Copper is used for non-sparking wrenches.

I had no idea Liquid Hydrogen was so much colder than Lliquid Nitrogen.
-423F versus -320F


----------



## SirDice (Nov 16, 2022)

Phishfry said:


> I had no idea Liquid Hydrogen was so much colder than Lliquid Nitrogen.
> -423F versus -320F


Yeah, it's quite a bit colder.

Cool documentary (pun intended):




_View: https://www.youtube.com/watch?v=sQ4J0jcAUec_





_View: https://www.youtube.com/watch?v=WX-cCa1oxpY_


----------



## astyle (Nov 16, 2022)

TIL an awful lot about new ways to play with cow pies. Not only are cow pies mostly hydrogen and nitrogen, those components are useful in such a starry capacity!


----------



## Phishfry (Nov 16, 2022)

We use liquid nitrogen to shrink in parts with heavy interference fits. Sleeves and bushings.
I tell everybody to be safe, but at the end of the job there are usually soda bottle bombs going off.
The power of cryo fluids is deceiving in so many ways.
I got my official training with LOX where the Navy shows training videos of all the possible disasters.
They are very blunt. Cryo fluids are dangerous.


----------



## Crivens (Nov 16, 2022)

Phishfry said:


> Too soft. Beryllium Copper is used for non-sparking wrenches.
> 
> I had no idea Liquid Hydrogen was so much colder than Lliquid Nitrogen.
> -423F versus -320F


Bronze does not only refer to copper/tin bronze. The material science course in university was fun - to a degree.

How many would go "Look how it crawls up the side of the container. How cute!" when faced with liquid helium?
Seeing the lower mm of soles still frozen to the ground where someone had jumped out of the way raises your respect for cryofluids a lot.


----------



## Jose (Nov 16, 2022)

Definitely should not be trying this




_View: https://www.youtube.com/watch?v=UjPxDOEdsX8_


Important safety tip: Do not soak the briquets in the liquid oxygen. They will explode when lit.


----------



## Crivens (Nov 16, 2022)

Jose said:


> Definitely should not be trying this
> 
> 
> Important safety tip: Do not soak the briquets in the liquid oxygen. They will explode when lit.


Purdue university, that prof got a cease and desist from the fire department. Schould they catch him with LOX ever again while being near a grill/campfire they'll go nuts on him.

I think every university needs someone like that. We had one guy who would do an experiemt and then stop the time for the guy from the electrical grid company to barge in and yell "We told you 1000 times NOT TO DO THAT!!"


----------



## eternal_noob (Nov 16, 2022)

astyle said:


> play with cow pies


🫣

People should focus on the problems down here instead of wasting resources.

Flying to the Moon is as useless as f*ck.


----------



## Crivens (Nov 16, 2022)

Maybe flying to the moon is akin to stepping on your doorstep. Who knows where you are a thousand steps from there, but you'll never find out without doing that first step.

You may put it into perspective. How many artemis is one twitter? Or where does ITER show up there? How many twitters is the defense budget? How many defense budgets are in the subsidaries for fossill fuels?
The biggest problem humanity has is that the wrong problems get the attention and money.


----------



## astyle (Nov 16, 2022)

Crivens said:


> Purdue university, that prof got a cease and desist from the fire department. Schould they catch him with LOX ever again while being near a grill/campfire they'll go nuts on him.


You realize that it's Purdue *Boilermakers*??? 
And Lox is a type of salmon?

FWIW, I love grilled salmon


----------



## ralphbsz (Nov 17, 2022)

Crivens said:


> I think every university needs someone like that.


When I was a grad student, our physics department had one of the very few liquid nitrogen making machines in the area. Once a year, the machine needs to be disassembled, cleaned, a few parts replaces, and most importantly: recalibrated. That's because any machine that can make liquid nitrogen can also make liquid oxygen and liquid argon, just by adjusting it (in-) correctly. Since LOx is very dangerous, it's important to regularly check the destillation part of a liquid nitrogen maker, to make sure it is really making LN2. The way our technician/machinist showed us: He deliberately misadjusts the machine too hot, until nothing comes out, then keeps adjusting it until some blu-colored liquid forms (which is LOx), then nothing, then a small amount (which is LAr), then a long range of nothing, and finally you get it adjusted just right at the bottom, and a heck of a lot of LN2 comes out. To be absolutely sure you are on the right side of the LOx temperature, you have to first see the large amount of LOx, then the small amount of LAr, and finally the flood of LN2, all going in one direction.

In this process, you end up with a few liters of LOx. The easiest and safest thing to do would be to let it evaporate, but that's not fun. Instead, you soak a few charcoil briquettes in it it (just a few), then put them in a BBQ, and light them with a very long stick. The explode like big firecrackers. Physics students love that kind of stuff.

The rest of the year, there was no way to get LOx.


----------



## Crivens (Nov 17, 2022)

ralphbsz said:


> Physics students love that kind of stuff.


Obligatory xkcd: https://xkcd.com/2662/


----------



## Jose (Nov 17, 2022)

I'd read that LN2 is made by fractional distillation of liquefied air, but had never heard a first hand account like yours. Thanks!


----------



## dgmm (Nov 17, 2022)

Crivens said:


> How many artemis is one twitter?


Somewhere between 1/3rd and a 1/2


----------



## Phishfry (Dec 12, 2022)

They say this thing orbited our Moon.






						Antonia Jaramillo Botero – Artemis
					






					blogs.nasa.gov
				




I am glad it all went well. My wallet is not relieved.


----------

