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-   -   Heads-up - uncontrolled reentry of large rocket booster projected May 8-10 (https://www.pprune.org/space-flight-operations/640279-heads-up-uncontrolled-reentry-large-rocket-booster-projected-may-8-10-a.html)

.Scott 7th May 2021 03:38

There has been no word at all from China.

Also, the aviation community is alerted because they are more likely to see something than others.
As far as the risk to aviation, its about the same for everyone. Airplanes may be more fragile, but they are also pretty compact - presenting a small target per passenger.

Right now, the aerospace prediction is down to a 32 hour window. Regions at higher than random chance of catching the rocket are the South Atlantic and the region around Japan include areas of China and the Pacific just east and west of Japan.

wiggy 7th May 2021 07:42

slacktide


The other issue with Skylab was ( shorthand description) an unusually solar active solar cycle made the upper atmosphere more dense then had been predicted and increased the rate of orbital decay, making even the most optimistic plans for a Shuttle boost redundant.

It's that sort of known unknown thats a driver for having a de-orbit plan..

rattman 7th May 2021 08:14

jolihokistix

They are but theres a margin of error, they normally give 12 hours warning of re entries or collisions.

WillowRun 6-3 7th May 2021 12:30

More info
 
Credit, SpacePolicyOnline (U.S. Secretary of Defense stating no plans to shoot down the rocket stage - plus good background information about this and related situations)

Austin: No Plans to Shoot Down Errant Chinese Rocket Stage – SpacePolicyOnline.com

wiggy 7th May 2021 13:43

A shoot down makes pretty zero sense anyway..the ironmongery won't just disappear, all that blowing the thing up does is risk increasing the amount of debris in Low Earth Orbit and/or increasing the size of the footprint on the Earth's surface likely to be on the receiving end of the incoming debris.

Less Hair 8th May 2021 13:02

Updated reentry prediction.
https://aerospace.org/reentries/cz-5...-body-id-48275

And some tweed:
https://twitter.com/planet4589

meleagertoo 8th May 2021 17:47

WillowRun 6-3

That is simply an April 1st headline.
What an utterly nonsensical concept - to 'shoot down' an object that is not airborne at all but is in free-fall!

Can there really be people so dim and naiive to even suggest or imagine such things?

ShyTorque 8th May 2021 19:49

I can’t see how something like this can be “shot down” because it’s on its way down anyway. However, presumably if it were broken into smaller pieces there would be more chance of it burning up more completely on re-entry (surface area to mass ratio is increased).

Less Hair 8th May 2021 20:43

Around 4:30 hours to go.

Big Pistons Forever 8th May 2021 21:02

Sadly another example of the Chinese government refusal to follow established norms of responsible behavior. Responsible governments which basically include all space capable governments except for China and North Korea, allow for some extra residual fuel to allow a managed descent. China loads up the rocket so every pound of fuel is needed to get the payload to orbit and then they throw away the launch body and basically walk away from any responsibility for the resulting uncontrolledly re-entry.

They know they can get away with such irresponsible behavior because there is not the political will to hold them accountable with meaningful sanctions.

wiggy 8th May 2021 23:15

Latest prediction from Space-Track..


projected re-entry at 2021-05-09 0204(UTC) +/- 60 minutes at latitude 41.6, longitude 350.7 (North Atlantic) NOTE: Getting closer to re-entry, but still not a precise time or location.
That peculiar Longitude translates as 9.7 west, in reality the plus/minus 60 min on the timing is effectively an uncertainty of a whole orbit plus a bit.

Other sources are predicting 0302 UTC with re-entry over the Pacific, but again with a big plus/minus....

We'll only know when it's happened.

India Four Two 9th May 2021 05:19

BBC: China rocket debris 'disintegrates over Indian Ocean' - Chinese media
https://www.bbc.com/news/science-environment-57045058

WillowRun 6-3 9th May 2021 12:46

meleagertoo

As this is R&N, even if the Secretary of Defense's answer to a reporter's question did not point out the silliness of the question itself, it's still worthy of a post to note the SecDef response. Going back to the news source, SpacePolicyOnline News reported Sec. Austin's comments as;
"At this point we don’t have a plan to shoot the rocket down. We’re hopeful it will land in a place where it won’t harm anyone. Hopefully in the ocean or someplace like that. I think this speaks to the fact that for those of us who operate in the space domain that there should be a requirement to operate in a safe and thoughtful mode and make sure that we take those kinds of things into consideration as we plan and conduct operations." (emphasis added).

If further factual information about where the rocket body re-entered and impacted, this update (from the same online source, noted in the space law and policy community as to reliability and accuracy of the site's proprietor):
"U.S. Space Command reports that the LM-5B rocket stage reentered over the Arabian Peninsula at approximately 10:15 pm EDT May 8. 'It is unknown if the debris impacted land or water.' Separately, NASA Administrator Bill Nelson criticized China for 'failing to meet responsible standards regarding their space debris.' Reports are that debris fell near the Maldives. China’s Xinhua reported a slightly different time (May 9 10:24 am Beijing Time, or May 8 10:24 pm EDT) and said the 'vast majority' of the rocket disintegrated and the rest of the debris fell in the sea in an area centered at 2.65 degrees North, 72.47 degrees East." (internal quotations in original; links converted to ordinary type)

The apparent sole holder of both expertise and authoritativeness, in the English-speaking world anyway, is a gentleman who also happens to be an astrophysics prof at Harvard. His site on Twtr social media platform is @planet4589. (I've met this gent several times in connection with professional and academic projects of mutual interest, and ladies and gentlemen, Prof. McD. is the real deal, for both expertise and authoritativeness on these sorts of subjects - however lacking this combination may be elsewhere.)

Big Pistons Forever

The contrary assertion, relative to the criticisms your post offers, is that it is the United States which has earned the title of Big Hypocrite insofar as norms of behavior are concerned. If you want more elaboration, look for the Twtr thread of the gent from SWF, Secure World Foundation (with a PhD and title like Policy Administration Director). I don't subscribe to the overall criticism, or any of its primary or logical elements - but it's where the discussion typically winds up.

As long as I've gone pedantic, for current diplomatic content on developing norms of responsible behavior in space check out the website where official comments (positions) by various countries, including United States, on the subject are posted (it's a U.N. deal, originated by the U.K., and currently in progress - if you don't have a seat at the negotiating table you might be surprised to find someone else wound up as the main course on the menu while you're only the soup, or maybe the parsley only).
Report of the Secretary-General on reducing space threats through norms, rules and principles of responsible behaviors (2021) – UNODA

Big Pistons Forever 9th May 2021 15:48

It is not rocket science........well I guess it is :O; but this issue is entirely about a policy decision on the part of the Chinese government not to engineer a planned entry. You can roll out a bunch of "whataboutisms" , but that does not change the facts. The current norm for space capable nations is to design a controlled re-entry system for all space debris that could survive re-entry. China did not do that and should therefore be called out for it.

etudiant 9th May 2021 22:36

If there is such a 'norm', it is nowhere articulated afaik.
It is simply that no one has sent up anything large enough to be noticed. The ISS presumably will get deorbited eventually under some control, but neither Skylab nor Mir had anything but orbital decay.

WillowRun 6-3 10th May 2021 00:32

etudiant

But there are several sets of rules close to norms, though dealing with orbital debris (and not in the form of an international convention or treaty). These are what people who work with international law refer to as "soft law". Attorneys, also diplomats and other governmental types, and of course a full complement of academics, non-lawyers as well as lawyers (a regrettable portion of this last subset having little if anything in the "actually representing a client" experience category).

There's a set of Debris Mitigation Guidelines. These were formulated and put into circulation by the IADC, Inter-Agency Space Debris Coordination Committee, an "international forum of governmental bodies for the coordination of activities related to the issues of man-made and natural debris in space." This was done under the auspices of UNOOSA, the U.N. Office of Outer Space Activities, and the multi-country U.N. forum COPUOS (Committee on Peaceful Uses of Outer Space). Relatedly COPUOS has issued "Guidelines for the Long-term Sustainability of Outer Space Activities."

Whether the concept of ultimate, maximum rocket fuel dedication for payload, paired with deliberate ignorance of risks of uncontrolled re-entry, is specifically rejected in any of these or other sets of guidelines (or proposed guidelines), I don't recall. This isn't quite the same problem area as orbital debris.

There's like a "cottage industry" in space law and policy focused upon debris, active debris removal, debris mitigation, and so on (lots of academic conferences, papers, research budgets). If I were a betting poster, I'd wager that one would be hard-pressed to find more than a sliver of this group which does not decry this act by China - not counting China's own space cadres, certainly.

Ascend Charlie 10th May 2021 05:19

"It won't land back in China, so it will not be our problem. And if it does, it will be because those aggressive countries interfered with our grand plans, in order to cause harm to our great nation of China. There WILL be consequences..."

averow 10th May 2021 10:00

China debris situation
 
Someday, at some point I reckon there will eventuallly be a bad outcome if China keeps launching "dumb" (unsteered, unplanned for safe landing) boosters into space. . Then we will have a mess on our hands. I wonder if there is a collective noun for deliberately pretending there isn't a lurking problem with a huge potential for disaster!

etudiant 10th May 2021 12:02

Thank you, WillowRun 6-3.
You've posted by far the best summary of the state of play for space hazard rules that I've ever seen. Clearly China pushed the tentative envelope with this launch, but 'soft law' has no teeth.
I think there are two more sections to be launched for the Chinese station. It will be interesting to see whether their boosters will likewise decay randomly, or whether China will make some effort to control their demise.

DaveReidUK 10th May 2021 13:44

The Chinese have been launching rockets without worrying about where they land for the last couple of millenia. :O

Old habits die hard.


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