The thread for space cadets!

[Timsup2nothin]

That's interesting, wouldn't have expected the steering thrusters to create that kind of visual effect. But what do I know, nothing apparently.

That's because "steering thruster," while correct, just doesn't have the pop to produce the proper mental image. Substitute "big ass nozzles spewing propellant" for the more technical term and it will provide more accurate expectations.

 

[Lexicus]

That's because "steering thruster," while correct, just doesn't have the pop to produce the proper mental image. Substitute "big ass nozzles spewing propellant" for the more technical term and it will provide more accurate expectations.

No, that's not what I mean at all. I mean simply that I would have expected the visual effect created by the "big ass nozzzles spewing propellant" to be more like fuzziness or debris on the largely straight exhaust trail of the rocket, not what appears to be an explosion. My initial guess was that the stuff exploded out like that because the rocket hit the tropopause or something and the exhaust trail just expanded outward like a cumulonimbus forming an anvil cloud, but I guess the thrusters were firing at a much higher altitude than that.

 

[hobbsyoyo]

Yeah stage sep happens around 100 mile altitude give or take.

 

[trader/warrior]

So, how come it explodes outward the way it does? About one second in the vapor trail, like, mushrooms out or whatever, where before it looked like a line.

I think the cause of the big "explosion" of exhaust that was so prominent in the sky is the boostback burn of the first stage fighting with the plume of the second stage. In this launch the booster immediately flipped and fired so the first and second stages are effectively firing against eachother.

As seen more clearly in this video. Then at about 3:30 you can see how the control thrusters look (pretty spaced out).

Of course the initial big control thruster burst to actually flip the booster may have an effect on this as well, but I can't really see it in any video.

 

[Broken_Erika]

Russians joke Soyuz rocket 'still heavier than air'

An Orthodox priest who blessed the Russian Soyuz rocket before lift-off has become the main source of mockery on social media after the launch ended in an emergency landing.

The Russian capsule experienced a booster problem which meant the two-man crew's six-month mission to the International Space Station has had to be delayed.

And with the news the crew - Alexey Ovchinin, a Russian cosmonaut, and Nick Hague an American astronaut - are in good health according to officials, attention has somewhat inevitably turned to the more humorous side of the misfire.

Many commentators have poked fun at a traditional blessing ritual performed by an Orthodox priest who sprinkled holy water on the rocket before the launch.

A prominent blogger Ilya Varlamov commented that "the rocket had been blessed before launch, but it was still heavier than the air".

However, some people have playfully blamed the priest himself with @atticus_flinch suggesting "the Soyuz crash was caused by poor quality holy water".

https://www.bbc.com/news/blogs-trending-45836111

 

[hobbsyoyo]

I think the cause of the big "explosion" of exhaust that was so prominent in the sky is the boostback burn of the first stage fighting with the plume of the second stage. In this launch the booster immediately flipped and fired so the first and second stages are effectively firing against eachother.

As seen more clearly in this video. Then at about 3:30 you can see how the control thrusters look (pretty spaced out).

Of course the initial big control thruster burst to actually flip the booster may have an effect on this as well, but I can't really see it in any video.

During initial stage separation, the first stage engine is off. It uses the exhaust from the second stage + large ACS burns to flip over. The main engines don't restart to begin the boost back for a bit after stage separation. Before that point it looks like the first stage is burning but it isn't - the Falcon first stage is as big as a building and it's painted white. In the seconds leading up to 3:04 it is turned fully to the sun and we're seeing its reflection. At 3:04 you can see the exhaust from the engines during start up as it has fully flipped over and begun the boostback sequence. Then at 3:30 (as you noted) you can clearly see the ACS engines firing.

The ACS thrusters are firing in the chaos of 2:45 - you just can't see them due to all of the plume impingement from the second stage kicking the first stage in the face with its exhaust.

A bit later the rocket will do an entry burn with the main engines - this is to lower the maximum dynamic pressure the rocket will experience during re-entry so it doesn't burn up. Then finally right before the rocket hits the ground it will do a landing burn.

The goal is to hit zero velocity exactly as you reach zero altitude - a fuel-saving maneuver called the suicide burn that conserves fuel. Interestingly, up until the final landing burn the vehicle is not actually headed toward land or the drone ship. Instead, it is heading toward a crash just shy of the land or landing barge. This is to ensure that should the engines fail to relight that the rocket will miss the landing pad entirely and thereby avoid damaging them.

This strategy saved the drone ship during the Falcon Heavy launch. During the landing of the center core of that rocket, one of the engines failed to start and the vehicle was unable to fully adjust its trajectory to make a landing and instead hit the water like a lawn dart just next to the drone ship.

Falcon Heavy Center Core Crash

 

[hobbsyoyo]

That maneuver where the second stage torches the first stage is called the 'fast flip' and it's something they slowly edged toward over multiple missions. It's really hard to know before hand how all the hardware on top of the stage will take getting blasted by rocket exhaust so they slowly walked the envelope up until they were satisfied that the interstage could take the pounding.

In this first image, we are looking up the skirt of the second stage nozzle on the left (that's not lewd - that's the legitimate technical description of what we are seeing). On the right is the second stage engine bell looking down into the interstage. You will notice on the left some struts that stick up into the nozzle throat. This strut assembly is the center pusher - it's a big rod that does a falcon punch right into the throat of the second stage merlin engine to push the stages apart.

Spoiler :

On this image, the second stage engine burn has just begun and it is torching the interstage.

Spoiler :

I developed tooling that allowed technicians to weld all of the tubes that are in the interstage. Those tubes provide pressurized gas to power things like the center pusher and the grid fins. I joined the company right as they were transitioning between the Block 2 and Block 3 versions of the Falcon 9. All of the tubing had changed so I had to develop all new tools. I developed a novel method of fabricating the tools that saved a lot of time and money.

By the time Block 4 rolled around, the process to swap out the tooling (yet again) was even faster and more comprehensive. I'm not sure how many of my tool sets are still in use with the newest Block 5 version.

 

[red_elk]

I liked the weightlessness indicator at 3.15

4.25 - Booster failure

https://www.bbc.com/news/blogs-trending-45836111

Orthodox blessing is obligatory procedure, without it the rocket would smash itself against the firmament.

 

[Thorgalaeg]

https://www.bbc.com/news/blogs-trending-45836111

OTOH the crew survived after a successful emergency landing. How many times has such thing happened instead of a deadly crash? I think this priest is good at his work.

 

[hobbsyoyo]

OTOH the crew survived after a successful emergency landing. How many times has such thing happened instead of a deadly crash? I think this priest is good at his work.

This is the third time the Soyuz has had a launch abort. The first time was further into the flight and the vehicle was more or less ripped off of the vehicle and put into a really steep re-entry trajectory that hurt (but did not kill) the cosmonauts. Even more dramatically, they landed on the edge of a cliff and were only saved when the capsule's parachutes caught in some trees that held stopped the capsule from rolling over the cliff.

The second time was when a Soyuz began to explode on the launch pad. Flames danced around the engine bays and quickly consumed the rocket over the course of a minute. The abort sequence was triggered with literal seconds to spare before the rocket exploded. The cosmonauts escaped injury.

This time, the launch escape tower had already jettisoned but the capsule retained an aerodynamic fairing which contained a smaller set of abort/escape rockets. It was this secondary, smaller set of rockets which pulled the capsule away from the Soyuz.

The Soyuz has a robust launch escape system.

Scott Manley did an excellent overview of the likely failure mode of this launch and the ConOps (concept of operations) of the launch escape system.

The particular failure mode was likely a ball lack that attaches the top of the side boosters to the main core. These ball locks are very similar to the locks used by the Falcon 9 to hold its landing legs in a stowed position for takeoff.

 

[hobbsyoyo]

So I'm sorry for double-posting so much but this is one of the biggest news weeks for space in recent memory. A lot of huge stuff went down this week.

First off, the USAF did a down-select for their next generation of launch vehicles. Four companies are thought to have submitted proposals for new rockets: ULA (Vulcan), Blue Origin (New Shephard), Orbital ATK/Northrup (OmegA) and SpaceX (upgraded Falcon or BFR). The Air Force chose only three - ULA, BO and NG - leaving SpaceX out of the mix. People were quite shocked that SpaceX got cut from this competition but it actually makes a lot of sense. SpaceX already has two rockets that can meet all of the requirements of the Air Force. An upgrade to the F9 or further development of the BFR just isn't necessary. Moreover, the Air Force really cares about having multiple launch vehicle options so it makes sense for them to spread the cash around to companies that have no rockets that meet their requirements (BO and NG) or that are retiring their current stable of rockets (ULA).

It's worth pointing out that ULA will use rocket engines provided by both BO and NG. Also, ULA and NG are separately buying the same engines from Aerojet Rocketdyne. It all gos to show how incestuous this industry is.

https://spacenews.com/air-force-fun...ds-to-buy-launch-services-from-two-providers/


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The Hubble Space Telescope (HST) suffered a failure in one of its gyroscopes and a second gyroscope is acting up as well. This means the telescope won't be able to do as much science or as high of a quality of science. Unfortunately, there are currently no vehicles which can service the telescope so it may go into a downward spiral and cease functioning altogether. There are some vehicles on the horizon that could potentially service the HST, namely the BFR. Boeing's StarLiner and SpaceX's Crew Dragon may also concievably service HST but this would be a stretch. There are some robotic vehicles on the horizon which may also service the HST or could even boost it into an orbit that would bring it close to the ISS for capture and servicing.

During the last HST servicing mission, NASA attached a set of grappling points for just such an eventuality so maybe the HST can be saved with some planning and lots of funding. I think it would be worth every dollar spent to save, to be honest. There are something like 15,000 scientific papers that were published using HST data.

Scott Manley has a great video on this subject.

Spoiler :

The Chandra X-Ray telescope also went into safe mode this week but from the little I've read on it is seems as if this was essentially a routine response to radiation and the vehicle quickly recovered.


---------

NASA's inspector general shredded Boeing for mismanagement of the SLS program. It also blamed NASA itself for failing to deal with Boeing's poor performance. The program has suffered a 100% cost increase and is at least 2 years behind schedule (depending on when you count as the start of the SLS program).

The program is so behind that NASA essentially psuedo-cancelled the upgraded second stage of the SLS as their won't be a core stage to accept this upgraded second stage when it would be ready. They are taking this delay to rethink the entire stage and potentially upgrade it even further as the current design of the upgraded second stage will still be dramatically under-powered for a rocket this size. This may mean we'll eventually get an SLS which can truly replicate the capabilities of the Saturn V but I think it more likely that this stage will be cancelled (along with the entire SLS) when BFR and New Glenn start flying.

Each SLS rocket currently has a 53 month lead time and a price tag of several billion dollars. For reference, Falcon Heavy has about a one year lead time at this point (and improving) and a $100m price tag for 2/3 the capability of the SLS. NG will likely have a price in the same ball park with 5/6 the capability of the SLS.

NASA needs to cancel this program but won't because congress won't let the given how much money this dumps into Alabama, Texas and Florida.

https://spacenews.com/nasa-inspector-general-sharply-criticizes-sls-core-stage-development/

Spoiler SLS test article under construction :

----------

China and India have also re-affirmed their committment to manned space flight. India's government announced their intention to have ISRO begin flying astronauts in the next couple of years and China is finishing ground testing for their next-generation crew capsule and heavy-lift rocket. Additionally, in a month's time China will launch the first lander to the dark side of the moon.

Also, coincidentally, the Chinese are developing their own Hubble Space Telescope and plan to co-orbit it with their upcoming space station which will make servicing it relatively easy.

Spoiler Chinese Capsule Test Article :

 

[hobbsyoyo]

These two dogs are the first creatures to go to orbit and make it back alive. One of them later had a puppy which was given to Kennedy by Kruschev as a gift.


The first animal in space died from heat exhaustion as their was no plan or ability to bring it back to Earth.

 

[caketastydelish]

I'm worried about Elon Musk's plan to have a colony on Mars.

The monumental costs of such a monstrosity aside, he's putting millions of innocent, gullible people (he said he wants millions to go with him) on this insane journey.

Here is what I mean:

Mars is only 'hospital' to people if you manipulate it with technology. It's cold for people to live on Mars without technology, same with being able to breathe, farm, etc.

No technology is 100% reliable 100% of the time. All it takes is one failure for the stuff to shut down and millions of people are dead. This is NOT like the Europeans going from the Mayflower to settle in the new world... the difference is it was still earth so you didn't need technology to be constantly up and running.

There are all kinds of things that can go wrong, not the least of which is an evil terrorist/hacker wanted to deliberately cause pain.

Your computer can freeze and crash which is an inconvenience but isn't fatal. You can experience dropped phone calls, same thing. People are going to depend on this technology running 100%, 100% of the time for their very existence, and this is a very selfish, dangerous game Musk is playing just so he can say he was the first person to bring a colony to another planet.

Obviously, Musk himself doesn't want anything bad to happen (and I pray he's right0 but he's taking the risk just because he's in the opportunity to do so.

 

[uppi]

No technology is 100% reliable 100% of the time. All it takes is one failure for the stuff to shut down and millions of people are dead. This is NOT like the Europeans going from the Mayflower to settle in the new world... the difference is it was still earth so you didn't need technology to be constantly up and running.

You got to give the engineers a bit more credit here. You don't design a life-support system without multiple redundancies and failovers. If one failure leads to everything being shut down, you have built a very bad system. In a good design it should take at least a few failures in a very short time for the system to go down and the probability for the occurrence of that should be near-zero.

Technical failures are a problem for self-sufficiency, because you will constantly need spare parts for broken stuff or else you die. But as long as the spare parts keep coming, technical failures shouldn't pose an existential threat to the colony. That doesn't mean it's not dangerous, but although the Plymouth colony was successful, other colonies were not.

 

[red_elk]

The particular failure mode was likely a ball lack that attaches the top of the side boosters to the main core. These ball locks are very similar to the locks used by the Falcon 9 to hold its landing legs in a stowed position for takeoff.

There are unofficial reports in Russian sources that ball lock binding (not sure if it's correct translation) was damaged during assembly.

 

[hobbsyoyo]

There are unofficial reports in Russian sources that ball lock binding (not sure if it's correct translation) was damaged during assembly.

That's an entirely credible theory. I would hard time believing it was anything but an integration failure given the design flaws in this rocket have been ironed out over the last 60 years.

In any case I'm in awe at how robust the Russian crew escape system is. If you watch the Scott Manley video I linked before he goes into detail on the three different abort scenarios the escape system is designed to handle that cover the entire launch sequence from the pad all the way up to space. Unfortunately with this failure we have seen all three abort modes in action - fortunately for those involved it worked.

 

[hobbsyoyo]

I'm worried about Elon Musk's plan to have a colony on Mars.

The monumental costs of such a monstrosity aside, he's putting millions of innocent, gullible people (he said he wants millions to go with him) on this insane journey.

Here is what I mean:

Mars is only 'hospital' to people if you manipulate it with technology. It's cold for people to live on Mars without technology, same with being able to breathe, farm, etc.

No technology is 100% reliable 100% of the time. All it takes is one failure for the stuff to shut down and millions of people are dead. This is NOT like the Europeans going from the Mayflower to settle in the new world... the difference is it was still earth so you didn't need technology to be constantly up and running.

There are all kinds of things that can go wrong, not the least of which is an evil terrorist/hacker wanted to deliberately cause pain.

Your computer can freeze and crash which is an inconvenience but isn't fatal. You can experience dropped phone calls, same thing. People are going to depend on this technology running 100%, 100% of the time for their very existence, and this is a very selfish, dangerous game Musk is playing just so he can say he was the first person to bring a colony to another planet.

Obviously, Musk himself doesn't want anything bad to happen (and I pray he's right0 but he's taking the risk just because he's in the opportunity to do so.

You got to give the engineers a bit more credit here. You don't design a life-support system without multiple redundancies and failovers. If one failure leads to everything being shut down, you have built a very bad system. In a good design it should take at least a few failures in a very short time for the system to go down and the probability for the occurrence of that should be near-zero.

Technical failures are a problem for self-sufficiency, because you will constantly need spare parts for broken stuff or else you die. But as long as the spare parts keep coming, technical failures shouldn't pose an existential threat to the colony. That doesn't mean it's not dangerous, but although the Plymouth colony was successful, other colonies were not.

I think that for the most part, you could set up a small self-sufficient colony such that technical failures wouldn't be devastating. Manufacturing technology has come to the point where you could send over 3D printers and basic machine tools that are capable enough to build most of the intricate parts you'd need to keep a colony running - or else use them to build more complicated machine tools that you need. Plus, it would help if they 'dumb down' the architecture of the colony itself to lessen the length of the necessary supply chain to keep things running.

What I mean is that say you have to design pumps to move air around your habitats - I would not design the most exquisite, most efficient pump for the job. Instead I'd design the most robust, easily replaceable pump that I could and use banks of those. That way when your pump fails, you don't have to rely on a 50-step industrial process to replace the internals of the pump - you just machine or forge new, simple parts out of iron and other locally available materials.

The achilles heel of a colony won't be the technology - it will be biological inputs. It will be a very long time before chemistry is sufficiently advanced to make all of the prerequisites for a full suite of modern medicines with only locally available non-biological inputs, for example. That's why I suggested to the internal suggestion box at SpaceX that they stuff the proposed Red Dragon capsule with long shelf-life medicines for a future colony.

 

[uppi]

I think that for the most part, you could set up a small self-sufficient colony such that technical failures wouldn't be devastating. Manufacturing technology has come to the point where you could send over 3D printers and basic machine tools that are capable enough to build most of the intricate parts you'd need to keep a colony running - or else use them to build more complicated machine tools that you need. Plus, it would help if they 'dumb down' the architecture of the colony itself to lessen the length of the necessary supply chain to keep things running.

What I mean is that say you have to design pumps to move air around your habitats - I would not design the most exquisite, most efficient pump for the job. Instead I'd design the most robust, easily replaceable pump that I could and use banks of those. That way when your pump fails, you don't have to rely on a 50-step industrial process to replace the internals of the pump - you just machine or forge new, simple parts out of iron and other locally available materials.

That would certainly be prudent. I would add that you want to standardize equipment as much as possible. So instead of having 20 different pump models for slightly different purposes, you would want to have as few designs as possible and try to be modular wherever you can. This means that you won't have to maintain many supply chains, but as few as possible.

The challenge is that a Mars colony will require a certain level of technical complexity. The supply chain for stone tools is rather short, but on Mars, those are not going to help you to survive, while on Earth they might. A big problem I see are electronics. To maintain the Mars colony, you would want a high level of automation, which means that there will be a lot of electronics needed. The supply chain for those is rather long and it is difficult to repair those. It would be a challenge to set up a supply chain on Mars that would be able to churn out advanced microchips, yet the colony won't function without those.

The question is, how much do you prioritize self-sufficiency against efficiency. For very specialized equipment that is not very heavy itself, but requires a long supply chain it would be more efficient to produce it on Earth and ship it to Mars, at least until the colony grows very large. But this compromises self-sufficiency, so you have to decide, how many supply ships per year you want to send.

The achilles heel of a colony won't be the technology - it will be biological inputs. It will be a very long time before chemistry is sufficiently advanced to make all of the prerequisites for a full suite of modern medicines with only locally available non-biological inputs, for example. That's why I suggested to the internal suggestion box at SpaceX that they stuff the proposed Red Dragon capsule with long shelf-life medicines for a future colony.

Immediately after basic nutrition has been secured, you would want to set up a Martian herb garden to provide at least some of those necessary biological inputs. But, yeah, that won't suffice for a full suite of modern medicines, so Martian colonists will die to causes that would be non-threatening on Earth. I fully expect that the life-expectancy of Martian colonists will be significantly reduced compared to those who stay on Earth.

The colony would most likely have a very controlled environment, which means that it would be fairly easy to eradicate infectious diseases there. This raises the question how much of that do you want to do? You could have a colony that is relatively disease-free, but then a fresh arrival, who is sick, might doom the colony if the immune systems of the colonists are not able to deal with the infectious agent.

 

[hobbsyoyo]

You're right - electronics will be a major issue for a while. However, given the number of small custom PCB manufacturing firms there are in the US, I don't think it's insurmountable. I will admit that I'm not sufficiently knowledgeable in the manufacturing process of electrical components (integrated circuits, PCB boards, resistors, capacitors, and so on) to know how easily you could set up small-scale manufacturing facilities for an entire electronics supply chain. Those small PCB manufacturing firms rely on components suppliers providing most of their inputs to turn into full boards.

I know you it is fairly straightforward to set up a machine shop to cut metal into 99% of everything you'll need mechanically but I don't know if the same can be said for electronics.

That said, you have identified the work around. By adopting flexible electronics platforms - something like a ruggedized breadboard format and a selection of standard components - you can easily meet most of your electronics needs by shipping over bulk quantities of simple components.

 

[uppi]

You're right - electronics will be a major issue for a while. However, given the number of small custom PCB manufacturing firms there are in the US, I don't think it's insurmountable. I will admit that I'm not sufficiently knowledgeable in the manufacturing process of electrical components (integrated circuits, PCB boards, resistors, capacitors, and so on) to know how easily you could set up small-scale manufacturing facilities for an entire electronics supply chain. Those small PCB manufacturing firms rely on components suppliers providing most of their inputs to turn into full boards.

PCBs are quite straightforward to produce. It's quite easy to set up a small scale operation for these. I am pretty sure, you could set up something up on Mars, provided you have some very basic chemistry supply chain. Integrated circuits are another matter, though. These require a much bigger supply chain and are much more complicated to set up.