Huge Rocket Looks Set For Uncontrolled Reentry Following Chinese Space Station Launch (spacenews.com) 135
Hmmmmmm shares a report from SpaceNews: The Long March 5B, a variant of China's largest rocket, successfully launched the 22.5-metric-ton Tianhe module from Wenchang Thursday local time. Tianhe separated from the core stage of the launcher after 492 seconds of flight, directly entering its planned initial orbit. Designed specifically to launch space station modules into low Earth orbit, the Long March 5B uniquely uses a core stage and four side boosters to place its payload directly into low Earth orbit. However this core stage is now also in orbit and is likely to make an uncontrolled reentry over the next days or week as growing interaction with the atmosphere drags it to Earth. If so, it will be one of the largest instances of uncontrolled reentry of a spacecraft and could potentially land on an inhabited area.
The high speed of the rocket body means it orbits the Earth roughly every 90 minutes and so a change of just a few minutes in reentry time results in reentry point thousands of kilometers away. The Long March 5B core stage's orbital inclination of 41.5 degrees means the rocket body passes a little farther north than New York, Madrid and Beijing and as far south as southern Chile and Wellington, New Zealand, and could make its reentry at any point within this area. The most likely event will see any debris surviving the intense heat of reentry falling into the oceans or uninhabited areas, but the risk remains of damage to people or property.
The high speed of the rocket body means it orbits the Earth roughly every 90 minutes and so a change of just a few minutes in reentry time results in reentry point thousands of kilometers away. The Long March 5B core stage's orbital inclination of 41.5 degrees means the rocket body passes a little farther north than New York, Madrid and Beijing and as far south as southern Chile and Wellington, New Zealand, and could make its reentry at any point within this area. The most likely event will see any debris surviving the intense heat of reentry falling into the oceans or uninhabited areas, but the risk remains of damage to people or property.
By design, like the previous ones (Score:4, Informative)
Re: By design, like the previous ones (Score:2, Interesting)
Re: It's called normalcy bias. (Score:2)
Maybe it'll counter the bias people have against the Chinese.
Re: It's called normalcy bias. (Score:2)
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So called "Low Earth Orbit" has a small amount of air present that induces drag. Everything there needs to be fueled to keep it there. There's no option to leverage it up there.
Re:By design, like the previous ones (Score:5, Interesting)
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What "nearby towns"? When? AFAIK none of Starships rained its debris on anything except the Boca Chica facility.
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Oh come on, don't let little things like "reality" and "facts" get in the way of a good anti-Musk hate-bitch. What kind of example are you trying to set here?
Re: By design, like the previous ones (Score:5, Insightful)
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Lol, you're claiming that SpaceX doesn't have a better record? Really? Maybe if you ignore the percent of uncontrolled reentries and just look at the raw numbers they don't have a better record, but that's straight up lying by omission.
Re: By design, like the previous ones (Score:3)
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So what was the plan to properly de-orbit it?
I know they considered using the Shuttle to collect it later, but as far as I can tell when it was launched there was no plan beyond "figure it out later".
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It's hard to link to things that didn't happen.
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"After fireballs streaked across sky, space-junk sleuths got busy — and hit the jackpot in Washington "
"Yet neither SpaceX nor the various federal agencies with some role in tracking space junk — the Federal Aviation Administration, NASA, and the U.S. Space Force — investigated what happened on the ground."
https://www.seattletimes.com/b... [seattletimes.com]
"NOAA’s Howard said the March 25 rocket reentry “should not be considered an isolated incident but rather a trend, given the vast amount of s
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Yeah, except he said it was a Starship, which never got within 1500 miles of Washington State.
So, as I said, it never happend.
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Right, my mistake for skimming the thread. Beyond the Starship launch site, only small and light bits that seemed to have drifted made it up to 5 miles away.
https://www.foxbusiness.com/te... [foxbusiness.com]
Re:By design, like the previous ones (Score:5, Informative)
The first stage of most rockets don't reach orbit, so they intentionally return in a harmless zone. The Long March 5B (both this launch and the initial launch of the design in May 2020) first stage reaches orbit
So, the dry weight of ~21 tons will fall back to Earth
Re: By design, like the previous ones (Score:4, Insightful)
What ? All in one spot at the same time ?
Re:By design, like the previous ones (Score:5, Insightful)
That's like a statistician saying they can walk across a river because on average it's only 4 feet deep, and then they drown in the attempt because average doesn't tell you shit when the middle is 10 feet with a strong current. It's completely irrelevant and useless in this discussion because that "40 tonnes of meteors" aren't a single 40-ton meteor.
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Re:By design, like the previous ones (Score:5, Insightful)
The average person has one ovary and one testicle.
No.
People have one ovary and one testicle on average.
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oh fuck that made me LOL
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What about the median person?
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That's like a statistician saying they can walk across a river because on average it's only 4 feet deep, and then they drown in the attempt because average doesn't tell you shit when the middle is 10 feet with a strong current.
I understand the point you are trying to make, and you are correct, but the example is a bit flawed. Even if it's exactly 4 feet deep all the way across, with "a strong current" you're going downstream anyway.
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Re:By design, like the previous ones (Score:5, Insightful)
...So, the dry weight of ~21 tons will fall back to Earth ... somewhere. This is about 10x bigger than the average mass of "uncontrolled re-entry" and pretty irresponsible of the Chinese.
When discussing something as potentially deadly as this, irresponsible isn't exactly the word that comes to mind.
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The estimates at the beginning were that there would be 2 million killed in a year. Considering that, Trump also saved 1.6 million people.
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This appears to be a feature, not a bug, of the Long March 5B rocket - although the Chinese aren't exactly being 100% forthcoming on it, either.
Which usually means a fuckup. If everything is going as planned, you brag about it.
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It's certainly possible they designed it without any plan for controlled re-entry, just like Skylab or some of the Russian vehicles and space stations.
It's irresponsible but also less than what other countries have done previously. Skylab, for example, was around 25 tons and parts of it were expected to hit the ground intact rather than breaking up or burning up.
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It's irresponsible but also less than what other countries have done previously.
Previous irresponsibility or irresponsibility of others is not an acceptable justification for continued irresponsibility.
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Yep, it is not a great design. (Adding a tiny amount of extra fuel or a small rocket (If it is low enough for the orbit to decay quickly enough, not much delta-V should needed to put a higher drag part of the orbit in a predictable place) to deorbit it in a predictable area would have been better). The summary / article leaves the impression that it is some kind of failure though.
The chance of it doing significant damage seems quite low though...
Re:By design, like the previous ones (Score:5, Informative)
Mostly burn up. Certain parts of it (principally core portions of the rocket engines) will survive re-entry and land...somewhere. The Chinese have been tight-lipped about whether the lack of de-orbiting is by design (i.e., they just didn't bother to include the capability) or by accident (i.e., they've lost control of the second stage). If China produced a rocket that doesn't have a capability to do a controlled de-orbiting, that is irresponsible, and should not be permitted - by armchair risk managers or professional ones.
Re: By design, like the previous ones (Score:5, Informative)
It's by design, China doesn't give a shit about the safety of anyone, be it foreigners or their own citizens.
Most Chinese launch sites are inland and their rockets travel a lot above ground, and parts routinely fall in populated areas.
"The authorities said the rocket parts fell where they expected them to and the residents in the area were given advance notice, according to local news reports."
https://www.inkstonenews.com/p... [inkstonenews.com]
They just don't care.
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That is obvious bullshit. Look, I get that you people do not like China, but ignoring what they can do only makes them more dangerous. In actual reality, one of the main engineering tasks for such an undertaking is risk assessment for anything and everything and that includes the current question.
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I gave you some sources, you just asserted "it's bullshit". Give some evidence supporting your statement or gtfo.
Fact is that China has four launch sites, 3 of which are deep inland, from which rockets travel above inhabited ground and dump parts and unburn fuel over the population.
There is a picture of a fucking rocket engine that fell on a house in the article I linked, but you're obviously too much of a moron to even bother looking at it.
Of course China did risk assessment, they know damn well what they
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Your sources are irrelevant. Youe claim is "they do not care" and that is complete and utter bullshit. They are just not prone to the typical baseless western panic, because they have not pussified themselves.
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Karma would be this junker landing directly on Xi's head.
Re: By design, like the previous ones (Score:4, Insightful)
You're right, i didn't, so i took your advice and checked it.
And lo and behold, you're right! Contrary to many other space launching nations, China does NOT have a few thousand kilometers of coast on their eastern end.
And that eastern cost they don't have is NOT on the biggest ocean on earth.
So you're right, and China is right to dump its rocket boosters and toxic rocket fuel on its population.
My bad.
Re:By design, like the previous ones (Score:5, Interesting)
Most of those are tiny, with a terminal velocity not much better than a fast pitch. And there's not much that anyone is expecting anyone else to do about it - such individual meteors can't be predicted, and we have no practical way to intercept them. But this is a man-made object put up into orbit intentionally. The means to do a controlled de-orbiting is both 1) technically straightforward, and 2) wouldn't substantially affect the rocket's cost or payload capacity.
In risk management there is a concept called "As Low As Reasonably Practicable" (ALARP [wikipedia.org]). It is a risk classification between Intolerable (risks that still need mitigation, or you scrap the project) and Broadly Acceptable (you've done enough to mitigate the risk, considering all other factors). ALARP describes risks that are worse than Broadly Acceptable, but there is no further practical means to mitigate it. The case of this rocket is not that: the risk of property damage, injury, or expensive cleanup has not been reduced to ALARP. There are practical and straightforward ways to mitigate the risk further - including a means for a controlled de-orbiting. Failing to include such a means to mitigate risk is 1) morally negligent, 2) a tragedy of the commons, and 3) a civil liability. Nation states can get away with such shit as a practical matter, because who is going to force them otherwise, but that doesn't mean they get a free pass.
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Well, given that letting this thing de-orbit by itself has lower risk than putting a small number of cars on a road, your argument is obvious bullshit. The only reason why this even gets into the press is because it is unusual. And the only reason why some people here go all irrational and insane is because it is China.
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Are they 21T meteorites?
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Are they 21T meteorites?
Not when they reach the ground. But the same is true for this Chinese rocket part.
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Depends on the frequency. Also, "littering" is not de-orbiting that stuff. That would be a real problem.
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Somewhere in the middle of the pacific....like,er, hawaii?
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And the facts are pretty clear as is the risk. And it's also clear China's government doesn't care about the risk, however low it is, of debris reaching the ground, most likely in some other country.
It's not just armchair risk managers criticizing them. Last time this happened the administrator of NASA made an unusual public statement criticizing the Chinese government for not having a way to deorbit the booster safely.
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The thing is that there are about 150 meteorite impacts on earth per day (these are the ones that do reach the surface). Adding a few more per year is not cause for concern or special measures.
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Except that it's not the same thing at all. Asteroid risk isn't something we can do much about. Boosters are entirely human-created risk that can and should be mitigated. That's just the responsible grown-up thing to do. All other space-faring countries try pretty hard to avoid this scenario if they can help it.
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You do not understand the argument. If there is already a high baseline, it is not sane trying to reduce a minimal impact you have on it with large effort.
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I assume it's the same thin metals you see everywhere else in the space industry?
It will be, because getting weight into orbit is expensive and so is building a one-time use device more sturdy than needed. The good thing is that all the armchair-experts will have been killed by meteorites (about 150 per day reach the surface of earth) or lightening strikes long before they ever come close to any of this debris, that is if any of it reaches the surface.
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It is expected that the engines and pressure vessels will make it to Earth, wherever they land. On a rocket this size, those could do some damage.
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It is expected that the engines and pressure vessels will make it to Earth, wherever they land. On a rocket this size, those could do some damage.
Yes. So? This is risk management, not "everything must be a safe as humanly possible". If the 2nd approach was sane, we would have to shut down every computer, car, power-plant, etc. immediately.
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Another rockets did a similar re-entry in 2020 [spacenews.com]. It is not a failure, but by design... (which does not feel clear from the article or summary) Another rockets also did it in 2016 [spaceflightnow.com].
If raining debris down on humans creating one of the largest instances of uncontrolled reentry of a spacecraft is by design, then where the fuck is the international safety committee that by design should be stepping in and stopping that kind of shit from happening?
Sure as hell hope no one gets hurt.
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Aehm, what? On a global scale, there is not relevant risk here. That committee you are calling for would not even have this thing on the long list of relevant threats to human life.
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There is such thing as a design failure.
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Re: By design, like the previous ones (Score:1)
By design, like the previous ones.
That sounds even worse... the PR is especially entertaining when one side has the self-awaereness that the ChiComs don't.
Good times; too bad I rarely drink.
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consider.
reporters got the planet name correctly
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Indeed. And the risks of that car or cow getting hit are pretty low.
Not the first time (Score:2)
This happened last year [arstechnica.com] as well.
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If they keep launching rockets from the same location that are trying for the same orbit, it'll probably just keep happening, raising the overall risk for that strip of land in the drop-zone.
Anyone remember when Skylab fell and landed bits in Australia, and NASA got fined for littering? Wiipedia has a good amount of information on the outcome of the de-orbit of Skylab.
It'll be interesting to see how things work out the first time we see real damage occur from an uncontrolled re-entry. I suppose it's only
Re: Not the first time (Score:3)
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I was thinking their problem is more a matter of
A) not having any RCS thrusters on the first stage
B) not being able to relight the first stage engine in space (this is not an easy thing to do)
C) not bothering with any first stage independent control since they can't A or B.
D) they didn't make any effort to do it because they simply don't care where it lands.
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OTOH, had they simply kept it sub-orbital, it would technically not be needed.
Problem was, D. They really do not give a fuck.
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This happened last year [arstechnica.com] as well.
Let's not forget Tiangong-1 [wikipedia.org] back in 2018.
oh well (Score:2, Troll)
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At least we were warned.
This is slashdot
We'll be warned again a few days after it crashes too.
Re: oh well (Score:3)
This is Slashdot. It probably already crashed onto granny.
I wouldn't know. Haven't read TFS. As I said: This is Slashdot! :)
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At least we were warned.
Which is about as effective as removing the blindfold while standing in front of a firing squad.
"Heads up, here it comes."
They're working on it (Score:5, Funny)
Just as soon as China has stolen all the details of Musk's rockets, this problem will go away.
Uniquely uses a core stage and four side boosters (Score:2)
This must be some new meaning to "uniquely". The Russians have been doing this for, what, 60+ years?
Re:Uniquely uses a core stage and four side booste (Score:5, Informative)
Nope, no Level 3 certification on that flight... (Score:2)
Not unless they get it back intact for inspection by their NAR witness.
heyy (Score:1)
WTF?!?!?! Gamble with YOUR life, not mine! (Score:1)
If I want to play Russian Roulette, let me do it on my terms!
Right now, and for the foreseeable future, I choose to NOT risk me life.
How about we let the debris rain down directly on Xi Jinping?
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Yep. This is just more "anti-China" propaganda. We had the same crap stories when it took off..
The Facts Say Otherwise (Score:5, Insightful)
You would also know that NASA Administrator Jim Bridenstein was critical of the previous Long March 5B, which landed in the Atlantic Ocean, but which, if the descent had started 15-30 minutes earlier, could have landed on U.S. soil. Whilst I would not claim that this proves anything definitive, I believe that it does show that this shows that it isn’t simply more of Elon Musk’s PR. Never mind anything else, Musk’s out-sized ego is such that if he had.a view on this then he would not rely on some hidden-hand PR, he would be making a big noise about it himself. I notice that you don’t quote anything from Musk directly.
From the excerpt posted here, you can see that the extent to which the vehicle’s orbit passes north and south of the equator is such that it over-flies the vast majority of the populated surface of the Earth. Now, in fairness, roughly 71% of the surface of the Earth is covered by water, so if it crashes at sea, the risk of significant loss of life is greatly reduced. But the fact remains that this launch does carry a more significant risk than one in which the first stage is either safely landed or where it is intentionally brought down over deep water.
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Probably also on the fact that the last Long March 5B had an uncontrolled re-entry, and China has not said this one will be controlled.
Re:The Facts Say Otherwise (Score:5, Informative)
First, I wouldn't say that I'm "basing" anything on "anything". Rather, I've followed the available links, read the materials and am offering quotations from that material. For example, if you click through you will find a link to this Twitter [twitter.com] page, which seems to have been provided by a Japanese amateur astronomer. In that post (Google Translate is your friend) you will see a comment on the brief video clip, in which the poster writes, (translated),
"It plays at 10x speed and leaves a trail. It was shining every 2.4 seconds. Because it was bright, it was thought to be the core stage, and it seems that the orbit did not deviate."
Am I qualified to say whether or not the video clip was of the first stage? Or qualified to say it was tumbling? No. But Andrew Jones of Space News may well be - and I was quoting Mr. Jones. Please feel free to draw your own conclusions.
Perhaps even more interesting, however, is your link to Wikipedia, to support your claim that Longmarch [sic] is "spin-stabilized". Except, if you go to the page and search for the term, "spin", you find a single reference, which reads,
"Long March 1's 1st and 2nd stage used nitric acid and Unsymmetrical dimethylhydrazine (UDMH) propellants, and its upper stage used a spin-stabilized solid rocket engine."
But that quote is for "Long March 1" and not "Long March 5B". The launch that we're discussing here is a 5B launch... The page that you link to does in fact provide an onward link to a dedicated Long March 5B [wikipedia.org] page, which also makes no mention of 5B being spin-stabilized.
But could this be wrong? Maybe. What about this Gizmodo [gizmodo.com] article, then? At the link, you'll see an article that quotes Jonathan McDowell, an astrophysicist at the Harvard-Smithsonian Center for Astrophysics, who discusses the fact that the 5B first stage isn't spin stabilized. The article notes the following:-
'Jonathan McDowell, an astrophysicist at the Harvard-Smithsonian Center for Astrophysics, suspects this is a deliberate design choice.
“Both CZ-5B launches have left their core stage in orbit for uncontrolled reentry,” he explained in an email. “They are over 20 [metric tons]. It has been standard practice for 30 years for the rest of the world not to leave objects this big—or even half this big—in orbit without controlled deorbit.”
To which he added: “This design choice in 2021 is unacceptable and tarnishes China’s great achievement in launching Tianhe.”
McDowell said a potential solution would be to add a system that vents “leftover propellant in a forwards direction to lower the perigee and make it reenter.” This would be “a bit tricky,” he noted, because the “dead rocket stage would be tumbling at that point,” but this solution would probably be cheaper “than adding a stabilization system and a restartable engine.” '
I don't even work in this field, never mind the fact that I'm not an expert in it. But it looks as though the preponderance of the evidence tells us that: the recent 5B launch may have left its first stage tumbling in orbit; that it looks as though this launch, like previous ones, has relinquished control of the vehicle; that this appears to be a design choice.
Very interested to know if you can share other resources which show that 5B actually is spin-stabilized.
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The Chinese are extremely concerned with public perception so I do not doubt they will add the capability at some point soon for a controlled de-orbit.
reentry predictions (Score:2)
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L
Re: Musk paid stories (Score:1)
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No.
Most first-stage boosters don't reach orbit, so calculating where they will land and making sure it's not going to hit anything of importance is very well understood at this point.
This booster goes into a degrading orbit, where it's practically impossible to figure out where it's going to come down. It could be the Pacific Ocean, it could be the car in my driveway. You, and everyone else, have no idea.
It's worth saying that the "danger" is incredibly small because Earth is really big, and most of it is
Re: Musk paid stories (Score:3)
With launcher, they should have control of all stages through all flight path, either in passive ( i.e.suborbital ) or active ( i.e. gas thrusters, mains, etc ).
Re: Funny dustinction. (Score:5, Informative)
China designed 5B so that first stage orbits, like a missile does. Once in orbit, if you lose control, then you are screwed.
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You people moderating this down do realize that underestimating an enemy is not a smart move, right?