Artemis II

[MostlyHarmless]

Yeah - saw the baskets on the Everyday Astronaut feed but no one else I've spoken to did. Maybe they didn't want them to get toasted by the exhaust? Can't recall seeing that happen last time though.

[TURIN]

The question was asked at the post launch press conference.
No, it wasn't supposed to get damaged..it should have been released several seconds earlier to be clear of the exhaust.
Or not. I can't find the video now but it was definitely mentioned alongside a few other anomalies such as the Comms cut out.

[tdracer]

Originally Posted by B Fraser

The exhaust from the SRBs seems to be a little dark at the point of ignition, was that a concrete rich exhaust plume ?

Could be from the ignition device they use - those ammonium-perchlorate based solid boosters are not easy to ignite, so some sort of highly energetic pyrogen is used to light the propellant.
Read somewhere that the solid boosters need to light off withing a few hundreds of a second of each other or the asymmetric thrust can cause catastrophic structural damage (at least that was the case of the Space Shuttle).
Using ammonium-perchlorate in my high-power hobby rocketry, trust me that getting both solid boosters to ignite within such a short time period is highly non-trivial...

[Bfah]

Toilet malfunction:
Apparently now fixed.

""..Not long ⁠after the successful launch, astronaut Christina Koch alerted mission control in Houston to a red blinking light signaling a problem with Orion’s toilet, housed in a small compartment within the crew cabin, itself only slightly larger than a minivan’s interior..."

A fan was stuck.
Ground control told them how to fix it.

Only $24 Million...!
"...On the ISS and Orion, astronauts use a $24 million Universal Waste Management ​System...",

What happens to the waste?
Bags of Poo floating around in space and bags of Poo lying on the surface of the moon. Imaging an alien walking along and going, wonder what this bag has inside it...'???

"....recycles urine into water and seals solid waste in bags.... that are eventually jettisoned..."

".... Apollo missions of the 1960s and 1970s used rudimentary bags attached to their bodies, storing them in onboard compartments or leaving them on the ⁠moon....".

[B Fraser]

Originally Posted by tdracer

Could be from the ignition device they use - those ammonium-perchlorate based solid boosters are not easy to ignite, so some sort of highly energetic pyrogen is used to light the propellant.
Read somewhere that the solid boosters need to light off withing a few hundreds of a second of each other or the asymmetric thrust can cause catastrophic structural damage (at least that was the case of the Space Shuttle).
Using ammonium-perchlorate in my high-power hobby rocketry, trust me that getting both solid boosters to ignite within such a short time period is highly non-trivial...

To be honest I don't think so. it looks like concrete dust to me but the post launch pad photos will be interesting.

I cover the SRBs in my Shuttle STEM talk and the igniter is at the nose end of the booster with the reaction doing the job all along the thrust channel within the propellant. The propellant is moulded in a particular shape at the pointy end that exposes the maximum surface area at the moment of launch, which then reduces as the material burns. It is the only way to have any control over the amount of thrust generated. The geometry of the fuel causes the thrust to decrease by some 33% at 50 seconds after launch to avoid over-stressing the vehicle i.e. the exposed reacting area is lowered.

Yes, the ignition has to be timed to a millisecond otherwise the stack would become the world's largest Catherine wheel. I'm surprised that the SRBs are not recovered on Artemis. The nozzles gimbal for directional control however they never solved the problem of the expensive end smacking into the Atlantic first, causing some rather costly damage. The Shuttle missions only lost 2 SRBs over the entire programme (other than Challenger where they were intentionally destroyed), a remarkable record.

I was watching one Artemis II feed where the talking head insisted that the SRBs could be extinguished by the introduction of an inert gas. OFFS ! I'll do a better job for expenses, a cold beer and a ringside seat.

For Shuttle SRB solid fuel perforations, what is the shape of the double-truncated-cone? - Space Exploration Stack Exchange

[B Fraser]

Originally Posted by Bfah

".... Apollo missions of the 1960s and 1970s used rudimentary bags attached to their bodies, storing them in onboard compartments or leaving them on the ⁠moon....".

You can't really avoid that topic if you are interested in the history of spaceflight. The process was rather gross and to be honest, I would be on a liquid diet for 48hrs prior to lift off. The top hat shaped receptacle had an adhesive ring at the "business" end and astronauts reported that had they known, any hair in that region would have been removed prior to flight. Liquid waste was pumped overboard but played havoc with taking star sightings through the navigation sextant.

Back in the days when astronauts were former fighter jocks, Rusty Schweickart commented on Apollo 9 that the most beautiful sight in the universe was the urine dump at sunset. Today's Disney groomed on-message PC inclusive outreaching space ambassadors will not be remembered for their witty comments. Strangely, we are becoming better yet poorer at the same time. I would have commented that constellation Urea was shining brightly off the port bow.

(On a long distance balloon flight some years back, I fitted a liquid jettison system in the basket which was used just after sunrise and while flying over Swindon, the dancing amber diamonds glittered in the morning rays of the sun. Delightful !)

[cavuman1]

During the entirety of the U.S. Space Program, the sparkling residue of the urine dump was fondly referred to as "The Constellation Urion!"

- Ed

[MostlyHarmless]

Think the baskets might have got a little toasty

[DogTailRed2]

After all these years since Apollo 11 can't help thinking the video feeds are a bit rubbish.
The commentary is also a little lack lustre. I'm not knocking the endeavour but as a spectator it's all a little underwhelming. In fact it's a bit boring.

[wiggy]

Originally Posted by Kiltrash

Given the flight management and computational power has improved so much in the 'old' days the craft would splash down somewhere in the Pacific,.......

In the early days the recovery force pretty much parked on the aim point on the basis that the spacecraft must miss.

So Apollo 8 came as a shock and frightened a few when during the final.stages of descent it directly overflew the carrier and ended up splashing down maybe 3 miles away....all in the dark.

This promptly led to a memo to those concerned from one of the senior operations managers at NASA (Bill Tindall) entitled:

"Let's move the recovery force a little"

They did.

[Bfah]

Looks like the loo/poo issue isn't done yet...

Apparently, the liquid uriane disposal exit port is iced up. News briefing said something about ''..once turned to the sun (aka Heating it), allowed half of the container to empty.

From what was said in the briefing the waste 'basket' is the size of a normal office waste basket, and of course it's gonna get filled quickly, with four people and three squares a day - One assumes that a square that a suckie nutrient/vitamin meal suffices for the 10 days.

[B Fraser]

Thank you for the toasty baskets image, I'll use that in a presentation at the end of this month on the Artemis II flight. I make a point of never using an image that 90% of the room will have seen unless there's an interesting detail hiding in plain sight.

[B Fraser]

Originally Posted by DogTailRed2

After all these years since Apollo 11 can't help thinking the video feeds are a bit rubbish.
The commentary is also a little lack lustre. I'm not knocking the endeavour but as a spectator it's all a little underwhelming. In fact it's a bit boring.

I could not agree more, calling the commentary shallow would be insulting to puddles. The numbers involved are incredible however I have missed any commentary on the rate of fuel flow or the rate of mass to thrust conversion. A great commentator stretches their audience and inspires curiosity. The words will go over the heads of some however others will be inspired to look closer. A good commentator can tell you a lot about physics by simply describing how and why the exhaust plume changes over time. How the persistent exhaust plume moves after the launch reveals the movement of the atmosphere etc. etc. etc.

If NASA are reading this, my fees are very reasonable. The late great Sir Patrick Moore did a slot for Canadian tv and refused payment or a contract, the handshake was all that was needed. He spoke for 3 minutes with no script and finished right on the money. They settled on a case of Canadian whiskey.

God, I do miss James Burke.

[Brian Pern]

Oh to have Journalists and commentators of yesteryear. James Burke is a legend, for those that have no idea of who he is. I was tempted to put the NTNOCN skit on but anyway , enjoy.

You Tube

[TURIN]

Originally Posted by B Fraser

I could not agree more, calling the commentary shallow would be insulting to puddles. The numbers involved are incredible however I have missed any commentary on the rate of fuel flow or the rate of mass to thrust conversion. A great commentator stretches their audience and inspires curiosity. The words will go over the heads of some however others will be inspired to look closer. A good commentator can tell you a lot about physics by simply describing how and why the exhaust plume changes over time. How the persistent exhaust plume moves after the launch reveals the movement of the atmosphere etc. etc. etc.

If NASA are reading this, my fees are very reasonable. The late great Sir Patrick Moore did a slot for Canadian tv and refused payment or a contract, the handshake was all that was needed. He spoke for 3 minutes with no script and finished right on the money. They settled on a case of Canadian whiskey.

God, I do miss James Burke.

Plus one on Mr Burke, a powerhouse among TV science presenters.
Great story about Patrick Moore, another legend.

Regarding shallow TV commentators, the YouTube channels such as NSF, Everyday Astronaut and Scott Manley are there for those that want something more in depth.

[BonnieLass]

I had the launch on TV in the background and it made me think back to Apollo 13.

Back in the day when the Apollo launches occurred there was understandable initial excitement at the prospect of travelling to the moon and all that it entailed. But after a while that excitement seemed to wain a bit, there wasn't the interest shown as each launch / return home was completed, it was seen as an almost vanity project that was wasting money.

Apollo 13 launch wasn't really watched that much, a sort of "oh not again" attitude prevailed, probably to do with the costs involved and what else was happening in the world at the time.

Then came the accident and that (no pun intended) reignited the interest and excitement and caused those people who had dismissed it or ignored "another" rocket to the moon as something that had to be watched due to the lives left hanging in the balance...a kind of "will they survive?" that til then was only seen in Hollywood movies and where every expert was rolled out to give their ideas on what happened and if the astronauts will make it back in one piece.

Artemis II hasn't really reignited the interest of space exploration, some may even feel that it is a technological step back....it started with rockets, then went to reusable shuttles and now back to rockets again.

Oddly and in some ways similar to Apollo 13 lack of interest, the issues with the toilet on board Artemis II has garnered more coverage than the entire expedition itself - and example of this being, reading in the comments section of one of the MSM...."was the toilet made by the same firm that made the toilets on the Ford aircraft carrier and was the important message conveyed to the astronauts to the effect of don't use the laundryroom".

Through no fault of NASA's timing, the Artemis II has been totally overshadowed by other events that are deemed to be more important so even when the world needs something exciting to watch and something to be proud of, it has totally missed that mark.

[cavuman1]

Space exploration is the most important and noble undertaking of our species.

- Ed

[MechEngr]

I recall some system for shutting down solid fuel motors by opening pressure reliefs and, after that, maybe some cooling gas would finish the job. At the least venting the pressure alone would eliminate the thrust. Not sure if it was investigated for the manned missions. Some propellants require both heat and pressure to release energy.

The freezing problem with the waste disposal suggest to me that the very best engineers were put on other things and that, perhaps, younger engineers, who have never had a urine flow issue, worked on the toilets.

[tdracer]

Originally Posted by MechEngr

I recall some system for shutting down solid fuel motors by opening pressure reliefs and, after that, maybe some cooling gas would finish the job. At the least venting the pressure alone would eliminate the thrust. Not sure if it was investigated for the manned missions. Some propellants require both heat and pressure to release energy.

You can kill the effective thrust relatively easily - ejecting the nozzle being one way - by getting rid of the high pressure within the 'combustion chamber' which will greatly slow the burn rate of the propellant (along with lacking a proper nozzle to accelerate the exhaust). In my hobby rocketry, the failure of the bottom (i.e. nozzle) or top closure stops any effective acceleration of the rocket (not a particularly uncommon failure).
OTOH, getting the propellant to stop burning is next to impossible - it'll burn just fine underwater - although on occasion the 'shock' of going from several hundred PSI to ambient pressure in an instant can cause pieces of the propellant to self-extinguish leaving bits of propellant in the debris. But even when that happens, it won't extinguish all the propellant, just parts.
All that being said, I'm unaware of any serious work on a system to kill the thrust from the solid boosters for Artemis. Rather, the emphasis was on the launch escape system being able to pull the capsule away from any catastrophic failure of the booster. It's significant that the launch escape system is not jettisoned until several seconds after the solid boosters separate.

[TURIN]

Originally Posted by MechEngr

I recall some system for shutting down solid fuel motors by opening pressure reliefs and, after that, maybe some cooling gas would finish the job. At the least venting the pressure alone would eliminate the thrust. Not sure if it was investigated for the manned missions. Some propellants require both heat and pressure to release energy.

The freezing problem with the waste disposal suggest to me that the very best engineers were put on other things and that, perhaps, younger engineers, who have never had a urine flow issue, worked on the toilets.

You could well be correct.

You Tube

Take a look at this video, 'big nang theory iss toilet' https://share.google/rQYgG2yuAiplDMKPK