SPACE - random thread about space stuff

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Re: SPACE - random thread about space stuff

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As if you didn't have enough to lay awake at night and worry about...
A large solar storm could knock out the power grid and the internet — an electrical engineer explains how
On Sept. 1 and 2, 1859, telegraph systems around the world failed catastrophically. The operators of the telegraphs reported receiving electrical shocks, telegraph paper catching fire, and being able to operate equipment with batteries disconnected. During the evenings, the aurora borealis, more commonly known as the northern lights, could be seen as far south as Colombia. Typically, these lights are only visible at higher latitudes, in northern Canada, Scandinavia and Siberia.

What the world experienced that day, now known as the Carrington Event, was a massive geomagnetic storm. These storms occur when a large bubble of superheated gas called plasma is ejected from the surface of the sun and hits the Earth. This bubble is known as a coronal mass ejection.

The plasma of a coronal mass ejection consists of a cloud of protons and electrons, which are electrically charged particles. When these particles reach the Earth, they interact with the magnetic field that surrounds the planet. This interaction causes the magnetic field to distort and weaken, which in turn leads to the strange behavior of the aurora borealis and other natural phenomena. As an electrical engineer who specializes in the power grid, I study how geomagnetic storms also threaten to cause power and internet outages and how to protect against that.
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Re: SPACE - random thread about space stuff

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A nice article about today's Artemis I Wet Dress Rehearsal and my favorite subject, liquid hydrogen :D
SLS wet dress rehearsal brings final major pre-flight test for NASA moon rocket
With the arrival of SLS and Orion at Pad-B on March 18, engineers and technicians have been busy making final preparations for Sunday’s critical last design verification test: the Wet Dress Rehearsal, or WDR.

The WDR will validate the vehicle’s readiness for flight as well as all elements of the new Mobile Launcher and pad propellant system upgrades for LC-39B’s liquid hydrogen storage and disposal systems — a multi-year process undertaken by NASA’s Exploration Ground Systems team.
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Re: SPACE - random thread about space stuff

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Need to Just Cause intensifies
It's almost as if people are the problem.
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Re: SPACE - random thread about space stuff

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Isgrimnur wrote: Sun Apr 03, 2022 11:10 am Need to Just Cause intensifies
??
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Re: SPACE - random thread about space stuff

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It's almost as if people are the problem.
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Re: SPACE - random thread about space stuff

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Ah yes :D.
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Re: SPACE - random thread about space stuff

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Re: SPACE - random thread about space stuff

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Zaxxon wrote: Sun Apr 03, 2022 2:14 pm
I think it's obvious that Berger has an axe to grind with Big Aerospace. Or does he think that magically every test goes off perfectly each time? And he keeps harping on cost-plus contracts, which as I've mentioned before is something else he has that axe for.
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Re: SPACE - random thread about space stuff

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Yeah, I was posting this one for the delay news, not the editorializing. In this case I think he's clearly off-base. Not like SpaceX has never had a 24-hour delay while loading...
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Re: SPACE - random thread about space stuff

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Zaxxon wrote: Sun Apr 03, 2022 2:41 pm Yeah, I was posting this one for the delay news, not the editorializing. In this case I think he's clearly off-base. Not like SpaceX has never had a 24-hour delay while loading...
The issue apparently is with the system that pressurizes the interior of the mobile launch tower to prevent ingestion of unwanted gases. It is probably the same type of system we used in Shuttle. Annoying, but not a fundamental problem as I understand it.

Also, it was odd that NASA decided not to broadcast the command channel audio for this test, something that was done for all the Shuttle non-DOD launches. They had some bogus sounding reasons but I think it was a mistake not to let the public hear what was going on.
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Re: SPACE - random thread about space stuff

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Neat razor ad in the middle :)

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Re: SPACE - random thread about space stuff

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This video is worthless without mushrooms or squirrels.
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Re: SPACE - random thread about space stuff

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Scrub for the day.




A less grudge-y but still mildly annoyed Berger update:

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Re: SPACE - random thread about space stuff

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What could possibly go wrong with loading those two without making sure that everything is working properly?
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Re: SPACE - random thread about space stuff

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If I wasn't such a modest person I would point out that when we did the first tanking test on STS-1 in the Space Shuttle program we successfully completed the tanking of each propellant (IIRC we tanked LH2 on a Tuesday and then LOX two days later) on schedule. If I wasn't so modest... :roll: :wink:
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Re: SPACE - random thread about space stuff

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jztemple2 wrote: Mon Apr 04, 2022 5:23 pm If I wasn't such a modest person I would point out that when we did the first tanking test on STS-1 in the Space Shuttle program we successfully completed the tanking of each propellant (IIRC we tanked LH2 on a Tuesday and then LOX two days later) on schedule. If I wasn't so modest... :roll: :wink:
Don't be so modest!
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Re: SPACE - random thread about space stuff

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There seems to be some confusion about which "vent valve" isn't working. I'm looking at the feed from Spaceflight Now.

There was this...
The Artemis launch team is evaluating a balky vent valve on the Space Launch System’s mobile launch tower. The valve on the mobile launcher's 160-foot-level failed to open, preventing the start of liquid hydrogen tanking into the core stage for today’s countdown dress rehearsal.
...but NASA replied,


That tells me it was a ground (GSE) issue, not a flight hardware issue. That to me is more of a oopsie since it's part of the ground systems which means it could have (and probably was) tested a lot. Also, if it is preventing a vent valve in the hydrogen venting system from opening, it seems especially odd to me since back in Shuttle (and most of the Artemis ground systems are based on Shuttle) this would be an actuation system with a secondary/redundancy function built into it. I would want to know if both the primary and secondary functions failed, or in an abundance of caution did they decide to scrub if they didn't have both available for the loading.
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Re: SPACE - random thread about space stuff

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The above post reminded me of an old war story of mine, which I'll relate if no one minds... no objections? :D

Back before the first Shuttle launch, one of the initiatives at that time was to cut down on the length of the countdown which actually started a few days before launch. Various parts of the S0007 Launch Countdown procedure were being critically examined to see which activities really needed to be done that close to launch day or could be moved out to earlier in the pad flow or even eliminated.

So one day I got a call to come up to the Launch Director's (LD) office. I had never been there before. The LD was the person in charge of all the activities for that flow once the orbiter was mated to the stack, and it was a pretty high and mighty position. The first and at that time current LD was George Page (link* to PDF of the Shuttle Launch Directors). Now Page was an old school boss, gruff, short tempered and rather intimidating.

I was asked by Page about a certain test that we ran twice, first just after the stacked vehicle was brought to the pad and mated, and then again during those S0007 launch preps. This test remotely cycled all the solenoid valves in our system sequentially. Those that had feedbacks we verified at the launch consoles, those that did not we verified by the tech actually placing their hand on it and verifying it was warm. Why, he wanted to know, were we running the same test a few weeks apart? Didn't we have confidence in our initial testing?

Now I had been working on the program (and actually in any post-college job) for less than four years, while Page was an old space veteran. But somehow I sensed something about his question. I replied that while we did have confidence in the initial run of the test, we also didn't want to go into cryogenic loading without being able to do a final confidence check as close as possible to the actual loading. After all, I said, I'd rather spend the several hours running the test than risk having to postpone the launch due to a failed component we could have easily found.

Page didn't say anything at first, then nodded and said OK and I left. Afterwards I figured out (at least I think it was true) that is wasn't so much what I said as much as the confidence I had in the reason for it. And for the rest of the program we ran that test twice each time the vehicle was at the pad, and honestly I don't remember us ever having a component that didn't work :wink:

Page was a good guy however, as I found out not too many weeks later. Minutes after STS-1 launched, just after engine shutdown, a NASA Project Engineer stopped by our launch console at which we were doing our first ever post-launch securing. He motioned for my boss and I to follow him and we climbed the stairs to the fourth floor of the LCC and were ushered into the Launch Director's office, me for the second time ever. We walked over to Page's desk, he stood up, shook our hands and thanked us for the hard work. And then he invited us to partake in the open bar which mysteriously had been set up in his office. A couple of the SRB guys were already there, since their boosters had finished their jobs two minutes after launch. I noticed that there weren't too many folks invited up from the firing room, so being invited there was quite a compliment :D

We stood up there for a while, long enough for the initial opening of the payload bay doors to be shown live on a monitor in his office. The camera looking from the aft cockpit windows showed something pretty shocking, a bunch of tiles were missing... that video feed was current restricted and we were asked not to mention anything till NASA officials had briefed the press across the road.

Not quite best day ever, but close :wink:

*If you're interested I'll tell you which Launch Director was part of our Rotisserie Baseball League :wink:. Hint, not George Page :D
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Re: SPACE - random thread about space stuff

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That's a great story.
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Re: SPACE - random thread about space stuff

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Awesome tale.

In other news, Amazon announced the start of Prime LEO by buying virtually all non-SpaceX launch capacity for the next several years.
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Re: SPACE - random thread about space stuff

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One mildly wishes he were in the office to hear the chatter rather than in the USVI for his wife’s work trip.

Mildly.
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Re: SPACE - random thread about space stuff

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Zaxxon wrote: Tue Apr 05, 2022 9:26 am In other news, Amazon announced the start of Prime LEO by buying virtually all non-SpaceX launch capacity for the next several years.
I read the article, holy crap that's a lot of launches. And except for Ariane, they will be flying from the Cape, about twenty miles from me :D
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Re: SPACE - random thread about space stuff

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I like the pic with the Launch Directors. Page is the only one not smiling. He looks like Josh Brolin as Agent-K.
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Re: SPACE - random thread about space stuff

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jztemple2 wrote: Tue Apr 05, 2022 11:23 am
Zaxxon wrote: Tue Apr 05, 2022 9:26 am In other news, Amazon announced the start of Prime LEO by buying virtually all non-SpaceX launch capacity for the next several years.
I read the article, holy crap that's a lot of launches. And except for Ariane, they will be flying from the Cape, about twenty miles from me :D
Great more space junk.
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Re: SPACE - random thread about space stuff

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Daehawk wrote: Tue Apr 05, 2022 12:15 pm Great more space junk.
You say space junk, I say more reasonably well paid employees moving to the area and paying property taxes to help fund more local improvements :D

By the way, the Artemis I wet dress rehearsal completion has been postponed till after the Axiom I launch on Friday April 8th.
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Re: SPACE - random thread about space stuff

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Here's another article about today's announcement from Amazon, Amazon purchases up to 83 launches for Project Kuiper, 50-65 of which could launch from the Space Coast. It's from our local Spectrum News affiliate so there's there's more focus on local impacts, like hiring from local college and universities and other local talent.

Now the Vulcan is made in Alabama and Colorado I believe, but New Glenn is being manufactured here. I'm not sure where the satellites are going to be made for Kuiper, but the One Web satellites are being manufactured locally right across the road from Blue Origin. And of course not part of the newly announced Project Kuiper, but SpaceX manufactures and refurbishes its boosters about a mile from the Blue Origin facility right here too.

I think the biggest question will be, where will everyone live? Housing is at a real premium in East Central Florida right now. Apartment occupancy rates are at an all time high. Houses are very expensive, even if you can find one. We get several offers each week for our house which is a fifteen minute drive from the Blue Origin facility. Also within a fifteen minute drive of my home there are several new massive apartment complexes going up plus new housing developments. Oh, and condos. We still need places for our old people to live :wink:
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Re: SPACE - random thread about space stuff

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Things looking good weather-wise for the Axiom-1 launch on Friday.

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Re: SPACE - random thread about space stuff

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I love that we've reached the point where humans go to space and it merits nary a mention here for hours afterward. Now do the moon!

Also, the sun is so cool...

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Re: SPACE - random thread about space stuff

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Zaxxon wrote: Fri Apr 08, 2022 11:54 pm I love that we've reached the point where humans go to space and it merits nary a mention here for hours afterward. Now do the moon!
Well, if the mission goes off normally and there's no issues to talk about there wasn't going to be much to post about. There were a lot of big crowds here at the Cape and lot of television coverage on our local affiliate. The weather was perfect, hardly a cloud in the sky and you could see the rocket on ascent all the way up until it was too far away to see.

Now, we'll see if Artemis I can finally gets their tanking test completed successfully.
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Re: SPACE - random thread about space stuff

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Regarding the Artemis I Wet Dress Rehearsal... NASA delays crucial Artemis 1 moon mission test to April 12
NASA has pushed back the resumption of the Artemis 1 moon mission's critical "wet dress rehearsal" by two days, to Tuesday (April 12).

The agency had planned to restart the wet dress — a practice run of rocket fueling and other important Artemis 1 prelaunch activities — today (April 9) at Pad 39B of the Kennedy Space Center (KSC) in Florida.

But the mission team decided to modify the test procedure after noticing a problem with a "helium check valve," which prevents the gas from escaping out of Artemis 1's huge Space Launch System (SLS) rocket. Helium is used to clear engine lines before loading and draining propellant, NASA officials explained in an Artemis 1 update today.
This pushes the actual cryo tanking to Thursday, April 14th.
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Re: SPACE - random thread about space stuff

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NASA scaling back Artemis 1 moon mission test due to faulty valve
The Artemis 1 wet dress rehearsal, which resumes Tuesday (April 12), won't feature a fueling of the moon rocket's upper stage.
The crucial "wet dress rehearsal" for NASA's Artemis 1 moon mission won't cover as much ground as the agency had originally hoped.

The wet dress rehearsal is a practice run for Artemis 1, which will use a Space Launch System (SLS) rocket to send an uncrewed Orion capsule on a roughly month-long journey around the moon. The test goes through many of Artemis 1's most important prelaunch activities, including fueling of the SLS.

The wet dress began on April 1 at Pad 39B at NASA's Kennedy Space Center (KSC) in Florida and was supposed to wrap up about 48 hours later. But several technical issues paused the proceedings, which were then halted to accommodate the April 8 launch of the private Ax-1 mission to the International Space Station from KSC's Pad 39A.
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Re: SPACE - random thread about space stuff

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After the wet test concludes successfully, do they subsequently drain the rocket? I know they plan to move the stack back to the VAB for some more fiddling around before the real launch.
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Re: SPACE - random thread about space stuff

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Kraken wrote: Mon Apr 11, 2022 9:41 pm After the wet test concludes successfully, do they subsequently drain the rocket? I know they plan to move the stack back to the VAB for some more fiddling around before the real launch.
Yes, they drain the liquid hydrogen and oxygen back to the storage areas.

I don't know what they are planning to do about the upper stage. Perhaps they will do a subsequent tanking test when they return to the pad.
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Re: SPACE - random thread about space stuff

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NASA Space Flight, 04/03
Originally built in the 1960s, LC-39B’s LH2 storage sphere is capable of holding 850,000 gallons of propellant. But from the beginning, there was a problem: the tank was losing more LH2 per day then design specifications.

By the end of the Shuttle program, it was losing 1,200 gallons of LH2 to boil-off a day.

“I happen to be the guy who found the void back in 2003, and it had been a problem with that storage tank from the beginning, from the start with Apollo,” said Mark Berg of NASA’s Cryogenic Propulsion Branch in an interview with NASASpaceflight.

The void referenced was the ultimate cause of the excessive LH2 evaporation in the tank — which was supposed to only lose 640 gallons of LH2 a day per design. For comparison, Pad-A’s LH2 tank averaged just 317 gallons of LH2 lost per day over its entire 60-year careeer.
...
The cause of the excessive evaporation from the Pad-B tank — which was not seen on the Pad-A tank — found by Mr. Berg ultimately related to a perlite bulk-fill insulation void in the storage sphere.
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Re: SPACE - random thread about space stuff

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jztemple2 wrote: Mon Apr 11, 2022 9:55 pm
Kraken wrote: Mon Apr 11, 2022 9:41 pm After the wet test concludes successfully, do they subsequently drain the rocket? I know they plan to move the stack back to the VAB for some more fiddling around before the real launch.
Yes, they drain the liquid hydrogen and oxygen back to the storage areas.
What's the expected loss of material from detanking?
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Re: SPACE - random thread about space stuff

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Isgrimnur wrote: Mon Apr 11, 2022 10:09 pm NASA Space Flight, 04/03
Originally built in the 1960s, LC-39B’s LH2 storage sphere is capable of holding 850,000 gallons of propellant. But from the beginning, there was a problem: the tank was losing more LH2 per day then design specifications.

By the end of the Shuttle program, it was losing 1,200 gallons of LH2 to boil-off a day.

“I happen to be the guy who found the void back in 2003, and it had been a problem with that storage tank from the beginning, from the start with Apollo,” said Mark Berg of NASA’s Cryogenic Propulsion Branch in an interview with NASASpaceflight.

The void referenced was the ultimate cause of the excessive LH2 evaporation in the tank — which was supposed to only lose 640 gallons of LH2 a day per design. For comparison, Pad-A’s LH2 tank averaged just 317 gallons of LH2 lost per day over its entire 60-year careeer.
...
The cause of the excessive evaporation from the Pad-B tank — which was not seen on the Pad-A tank — found by Mr. Berg ultimately related to a perlite bulk-fill insulation void in the storage sphere.
Well, there's your problem. The Pad A tank used vacuum insulation while the Pad B tank uses a perlite insulator, which isn't as efficient. I can tell you all about the Pad A tank because I was working as a field engineer at the LH2 facility during the re-activation after Apollo prior to its use for Shuttle. In fact I can remember sitting on the top of the tank one pre-dawn Sunday morning in early 1978 with the lead tech. We were pumping down the annulus space, which is pretty large on that large a tank. We had to get down to under 25 microns* of pressure in the annulus. The lead tech had to be up there to watch the gauge and I felt that it was my place to sit up there with him instead of a nice (reasonably) comfortable trailer. We were up there several hours till just as dawn was breaking we agreed (by squinting at the needle) that we had reached that 25 micron limit.

*A micron refers to a micrometer of mercury. As vacuum technology advanced, it became necessary to have a more precise vacuum measurement unit than the mm of Hg. The mm of Hg was divided into 1000 smaller parts which were called microns. Regular atmospheric pressure is 29.92 inches of mercury or 760 mm Hg. So 25 microns is 0.00003289 of atmospheric pressure.
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Re: SPACE - random thread about space stuff

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Isgrimnur wrote: Mon Apr 11, 2022 10:12 pm
jztemple2 wrote: Mon Apr 11, 2022 9:55 pm
Kraken wrote: Mon Apr 11, 2022 9:41 pm After the wet test concludes successfully, do they subsequently drain the rocket? I know they plan to move the stack back to the VAB for some more fiddling around before the real launch.
Yes, they drain the liquid hydrogen and oxygen back to the storage areas.
What's the expected loss of material from detanking?
I can't speak for LOX, but IIRC in Shuttle we had an 800,000 LH2 storage tank feeding the External Tank which had a 382,000 gallon capacity. The storage tank was normally not full to allow for some ullage space for pressurization. We could tank and drain twice, doing a 24 hour turnaround, but then we had to wait at least 48 hours for the next attempt because we had to bring in a couple of waves of tankers to top off the tank again. Again, IIRC a normal tanking plus sitting in replenish for several hours then draining used up about 100,000 gallons of LH2. We wouldn't want to start loading with less than 500,000 in the tank because you didn't want to get the liquid level too low in the tank.

Those LH2 tankers, by the way, had to come all the way from New Orleans, so for the initial launch attempt they would be staged at NO, ready to fill. If we scrubbed after the first attempt the tankers would be filled and sent, getting here some time after a second launch attempt the next day. If we had scrubbed on the second attempt after a normal tanking we'd just offload the LH2 into our storage tank. However, if on the second attempt we never got to LH2 tanking for some reason we'd have the tankers hold at a stand-by site at the Space Center. They couldn't remain indefinitely since the contractor needed those tankers back in New Orleans. If for some reason we wouldn't have a launch attempt for awhile, we'd offload what LH2 we could into the storage sphere and then see which other users on the Cape and at KSC could use the rest of the liquid hydrogen.
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jztemple2
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Re: SPACE - random thread about space stuff

Post by jztemple2 »

Not quite space, but close enough to be posted I think. Space Perspective unveils lavish interior of balloon-borne tourist capsule
Spaceship Neptune will start carrying customers to the stratosphere in 2024, if all goes according to plan.

Space Perspective wants its passengers to fly in style.

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The Florida-based company is working to send paying customers (as well as research payloads) to the stratosphere aboard its "Spaceship Neptune," a pressurized capsule that will cruise high above Earth beneath an enormous balloon.

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Space Perspective just released artist's illustrations of the interior of Spaceship Neptune, which will include 360-degree panoramic windows and even a restroom with a view. The announcement Tuesday (April 12) coincided with the anniversary of the first human spaceflight by cosmonaut Yuri Gagarin in 1961.
Ahem! The April 12th announcement also coincided with the anniversary of the first Space Shuttle launch... I really wish we had gone on the 11th :roll:
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Re: SPACE - random thread about space stuff

Post by Daehawk »

ty blues news

'Dead sunspot' launches ball of plasma toward Earth
The "corpse" of a sunspot exploded Monday (April 11), triggering a mass ejection of solar material that is headed in Earth's direction.

The explosion comes courtesy of a dead sunspot called AR2987, according to SpaceWeather.com (opens in new tab). The sunspot explosion released loads of energy in the form of radiation, which also led to a coronal mass ejection (CME) — explosive balls of solar material — both of which could spur more intense northern lights in Earth's upper atmosphere. The material in that CME is likely to impact Earth on April 14, according to SpaceWeather.
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