CZ5B (Chinese rocket) Reentry Prediction

https://aerospace.org/reentries/cz-5b-rb-id-53240

by Kaibeezy • 4 years ago

89 96 4 years ago

aerospace.org

seventytwo• 4 years ago

Am I reading this correctly that this is gonna fall over lots of populated areas?

tgv2• 4 years ago

If I interpret it properly, most of the path is over the ocean. Debris might still hit Indonesia though.

MichaelCollins6• 4 years ago

China is known for dropping rocket boosters on their own towns fairly regularly. For instance: https://twitter.com/ChinaSpaceNews/status/637174369677123584

With China situated where it is, this sort of thing is hard for them to avoid. Probably they want to eventually switch to fully reusable rockets, but that's a touch nut to crack.

ARandomerDude• 4 years ago

With China situated where it is, this sort of thing is hard for them to avoid.

Sea launch or contract launch sites are good ways to avoid it.

bpodgursky2• 4 years ago

Maybe I'm missing something, but China has an enormous east-facing coastline. Why not launch from Hainan over the Pacific? It's basically Florida but better-situated.

mlindner9• 4 years ago

The curve shown is the entire uncertainty bar on the location. It's +/- 1 hour of the center.

tgv2• 4 years ago

That's a pretty sad state of affairs. For what, prestige?

88840-8855• 4 years ago

Science and prestige probably.

Don't forget that China is still catching up. In the 80s, when it started developing, China was poorer than any African country.

The Soviets and Americans also did a lot of borderline and dangerous stuff when doing prestige and science.

Times changes here in the WeSt where safety is first. It will also be in China one day, too.

tjpnz3• 4 years ago

The US program wasn't known for dropping boosters onto villages and dousing residents with hypergolic propellants in the process. While the US program did take a lot of risks early on it would be incorrect to suggest any equivalence in attitudes towards risk management.

serf• 4 years ago

The Soviets and Americans also did a lot of borderline and dangerous stuff when doing prestige and science.

the difference being that the cold war fueled novel R&D and science that the world had never seen; the Long March is a tool that was created as a means to chase after the capabilities of similar Heavy-Lift style rockets. The experimentation of the Cold War was fairly tightly controlled and limited in quantity; the Long March is supposed to be used for generally all space construction for the foreseeable future.

Given that this class of tool exists in the world already, all we can be asked to do is judge it against its' peers. They all have had accidents, but if the Long March is going to be known for spraying debris across the planet then this is a problem that everyone must pay attention to, regardless of where China has progressed to with regards to their safety culture.

We're not talking about Chinese safety when we're referring to space debris; this encapsulates the entire world.

FooBarWidget4• 4 years ago

Necessity.

China is banned from international space cooperation. They have to master space technology themselves because they can't rely on others. In order to do that, risks must be taken and sacrifices are necessary.

On a broader level, the Chinese think they made a mistake in not investing in science and technology for so long (read: the past couple hundred years). They see lack of science and technology as one of the main reasons why the were so miserable the past 150 years (minus the past 40 years or so). So they're not going to make that mistake again.

It's perhaps the "sacrifices are necessary" point that western commentators most disagree with. After all it goes against the idea of individual freedom. But China is very much a country that prioritizes collective interests over individual interests. This isn't even a weird thing on the world stage: most Asian countries have a similar mindset.

bryananderson3• 4 years ago

I can’t emphasize enough how not necessary it is to have the upper stage of CZ-5B reenter uncontrolled. Nudging the stage into the atmosphere while over an ocean is a much easier problem than launching the rocket on a precise trajectory to rendezvous with a space station. China clearly has the capability; not doing it is a choice.

mlindner9• 4 years ago

This is wrong on numerous points.

China is banned from international space cooperation.

Firstly, China is not banned from international space cooperation. They have worked with several other agencies including ESA and Roscosmos. The only ban that exists is the US restricting China from working with it because of a history of their seizing and stealing of US civil space technology for military purposes.

In order to do that, risks must be taken and sacrifices are necessary.

You can take risks and sacrifices without endangering the general public of your own country and especially without endangering the public of the world. China has the technology to de-orbit vehicles, they just refuse to implement it on some vehicles.

They see lack of science and technology as one of the main reasons why the were so miserable the past 150 years (minus the past 40 years or so).

This is the myth of "chinese national humiliation" that is a common talking point of Chinese nationalists and is used to foment nationalist sentiment. Repeating it doesn't make it real.

But China is very much a country that prioritizes collective interests over individual interests.

You can do that (with criticism) and endanger the population of your own country but you can't at all do that internationally. That's a ridiculous claim.

This isn't even a weird thing on the world stage: most Asian countries have a similar mindset.

This is again completely false. Japan values the life of an individual at even higher levels than we do in the US. It's not an Asian sentiment. It's a Chinese Communist Party sentiment. (BTW this technique of expanding their own values to all of Asia is something that Imperial Japan did heavily in the decades lead up to WW2. Let's hope China doesn't head along a similiar route. https://en.wikipedia.org/wiki/Greater_East_Asia_Co-Prosperit...)

mdp2021• 4 years ago

In May 2020, two villages in Ivory Coast were hit by objects – including a 12-metre section of pipe – that appeared to have come from a Chinese Long March 5B expected to land that day
[Dr Shane] Walsh [International Centre for Radio Astronomy Research: ]«They claim to have learned from the last two launches and added some method of control, but the EU tracking network showed this unit is tumbling, which means it’s not controlled»
The US and the EU have embedded risk assessments and will not launch if there is a greater than one in 10,000 chance of causing injury. China appears to have a much lower bar

(From The Guardian: https://www.theguardian.com/world/2022/jul/29/as-more-space-... )

Some would have though from at least last episode in May 2021 that it finally appeared as clear that fatalist and jus-formalist orientations and behaviours are largely frowned upon.

troyvit• 4 years ago

There are no consequences beyond being frowned upon it looks like. One of the perks of being a super power I guess?

JumpCrisscross• 4 years ago

perks of being a super power

China is a regional power vying for superpower status. To memory, nobody has ever been punished for fucking up launch and recovery. (EDIT: I stand corrected!)

publicola19902• 4 years ago

If there is any damage due to debris, they will be liabale under the Space Liability Convention 1972 to which they are signatory to. That will be the consequence.

Both USSR and US had in the past pay out due to this convention in the past. USSR for debris from a Kosmos impacting Canada, and US for Skylab fragments impacting Australia.

yorwba• 4 years ago

The US and the EU have embedded risk assessments and will not launch if there is a greater than one in 10,000 chance of causing injury.

This may seem like a strict requirement, but the surface of the Earth is quite big (510 trillion square meters) compared to how many people there are (7.79 billion), so only about one in 65,000 square meters even has a human on it.

aaron695• 4 years ago

Very cool space junk was found in Australia this week, it's like it's out of a movie -

https://www.abc.net.au/news/2022-07-29/space-junk-found-in-n...

It'd be cool to get close to where this stuff goes down, but it's impossible. Just good luck.

I think seeing the ISS come down in the pacific in 2031 would be cool. Hopefully NASA will help rather than hinder this.

peteradio• 4 years ago

That video is incredible. "It's kinda incredible really having this piece of space junk fallin in me uhhh ... paddy. You know think of what else is out there in uhh other people's paddies. inaudible above my children's weird minecraft videos Yeh? I suppose you wouldn't fare too well if a piece landed on yuh"

MichaelCollins6• 4 years ago

Probably best not to get too close unless you know exactly what it is. Hydrazine is very toxic and probably carcinogenic. It would be cool to watch a reentry like that, but I don't think I'd get as close to the debris as that guy is.

13of40• 4 years ago

It looks like it might be made of carbon fiber as well, which tends to burrow into bare skin when you touch it. I definitely wouldn't take a selfie with my hand resting on it like that guy.

I'm not sure they still do it, but Soyuz(?) used to have a radiation source on the bottom to use as a kind of altitude detector, so if one of those broke up there could be another surprise for someone who found debris.

throwaway4good5• 4 years ago

Imagine the coverage of this had that thing been Chinese.

mlindner9• 4 years ago

It would have been marginally increased compared to what it got, however this thing is not a 20+ ton object like the Chinese stage. It's a few hundred kg. The western press hasn't cared about other re-entering Chinese stages until they start lofting entire main stages into orbit much larger than almost anything in history to re-enter. (The only things larger to re-enter uncontrolled were full space stations, which has only occurred a couple times in history.)

JayGuerette• 4 years ago

1. Disguise payload as space junk 2. Design to "fall" on populated area 3. Say "oops" 4. ...

ethbr06• 4 years ago

What payload would possibly be worth this, that wouldn't be more effectively served by a different delivery mechanism?

matthewaveryusa• 4 years ago

a plausibly deniable payload purpose

raverbashing2• 4 years ago

You're forgetting about what happens when something "falls" from the atmosphere uncontrolled

iNate2000• 4 years ago

But what if it only appears uncontrolled?

m3kw9• 4 years ago

Make it land on a valuable target and not make it looks suspicious?

throwaway4good5• 4 years ago

It is going to land in the water.

The Chinese know what they are doing.

MichaelCollins6• 4 years ago

Yes they know what they're doing, but what they're doing is taking calculated risks. They don't know it's going to land in the water, and their rocket boosters often don't. They understand this risk, and accept it.

Rebelgecko2• 4 years ago

Are you saying they're able to control it somehow?

throwaway4good5• 4 years ago

I am saying they know more about how this thing will fall and desolve than journalists or US defense organisations that have interest in drumming up fear either as a way to get attention or in a broder anti-China effort.

We will see in a couple of hours.

JustSomeNobody2• 4 years ago

Nobody knows what they're doing to the degree of keeping people perfectly safe. Too many variables in how this thing will interact with the atmosphere on re-entry.

mlindner9• 4 years ago

Indeed. The stage is wildly tumbling through the edges of the atmosphere and the atmosphere is not continuous but "lumpy" with areas of higher and lower drag.

mlindner9• 4 years ago

The Chinese don't have any control over this stage. It's tumbling in space (as seen by several observers). They know they're leaving debris in space, but they have no idea where it will land. They continue to lie to their own public and the international public on every launch that the vehicle is controlled.

dudeinjapan• 4 years ago

70% chance. I'll take those odds.

ronyclau• 4 years ago

There is a documentary named "Falling from the Sky"[1] from 2009, which depicts how scared and helpless people in a Hunan village were, every time a rocket wss launched from Xichang Satellite Launch Center. The village was located within the area where rocket debris would fall, and the villagers were basically told to suck it up by officials.

[1] https://www.imdb.com/title/tt2136916/

r7214• 4 years ago

See also this NYT piece with a lot of photos:

Remote Russians Recycle Rocket Wreckage
Space junk from rockets launched from the Plesetsk Cosmodrome in Russia ends up in the remote Mezensky District, where residents repurpose it for hunting sleds, tools and boats.

https://www.nytimes.com/2018/09/26/lens/space-rocket-parts-r...

blinding-streak2• 4 years ago

That is a fantastic alliteration.

AlbertCory• 4 years ago

Headline writers amusing themselves.

WSJ headlines tend toward puns.

GekkePrutser• 4 years ago

I can't really help not feeling bad for them. I think the Chinese people need a reality check. Hopefully this kind of movie will spread awareness. The people that should feel bad are those supporting the regime.

The CCP exists because the Chinese let it exist. If they want to have a fair society they'll have to overthrow it sooner or later. We can't do it for them. There is no other way. Even sanctions hurt the people more than the regime (see North Korea). People are nothing but livestock to them. Hopefully these examples will help teach the population to see what they really are. The people 'displaced' by the Olympics are another example.

It seems pretty popular still, but cracks seem to be forming after the heavy-handed Corona measures in Shanghai. I'm hoping it will sow the seeds of discontent and eventually a revolution will happen. Or a gradual move to democracy perhaps. But the tighter controlled a dictatorship is, the lower the chance of that.

Maybe I'm too optimistic but I think that dictatorships will always fall eventually. Even strict ones like China and North Korea.

throwaway4good5• 4 years ago

In the 90es China used to send up satellites for US companies; cheap and cheerful until a major accident happened:

https://en.wikipedia.org/wiki/Intelsat_708

And after the accident; the Chinese fixed their rockets and the Americans started their boycot; including banning them from the ISS leading to the space station program the CZ5B is a part of.

Today the Chinese space program is a source of national pride and is cherred and followed as the US space program was in its heyday.

Fatnino• 4 years ago

The Chinese fixed their rockets using classified information that the American companies leaked in their report on the crash. This gave the Chinese missile industry a major advance in guidance tech.

In recent years the "cherred" (sic) Chinese space program has heavily borrowed without asking from the soviet and other world space programs to race through a checklist of space achievements the Chinese want to pretend they developed themselves.

For example: see Shenzhou 5's uncanny resemblance to a Soyuz capsule.

Now, to be sure, China hasn't cloned these 1:1. They have even managed to hit checklist items that the rest of the world hasn't got to yet, like communicating with a spacecraft landed on the far side of the moon. But foreign design bones are deeply embedded in their entire program and it's plainly visible to any that care to look.

Contrast this behavior to the US/Soviet space race where each side developed unique spacecraft and spacestation designs with unique abilities and unique degrees of success. With one exception: in the late 80s, on the verge of their collapse, the soviets copied the American spaceshuttle. They even made it better than the American version in almost every way but didn't realize that the entire concept was a huge boondoggle that was a mistake for the US to even develop and fly.

r7214• 4 years ago

Their twitter account to watch for updates: https://twitter.com/AerospaceCorp

TedDoesntTalk• 4 years ago

I still remember when Skylab fell to Earth in 1979. I was 9. People on TV who found items (and others who claimed they did by manufacturing junk with aluminum foil). It was inspirational. We looked to the sky at the right time to see what we could see. I wish I could share that with my kid, but he’s away this weekend.

publicola19902• 4 years ago

There seems a video going the rounds on twitter of its trails over the night sky somewhere in Malaysia[1].

[1] https://twitter.com/AJ_FI/status/1553425522369118208?cxt=HHw...

r7214• 4 years ago

Thread: https://twitter.com/DELTA_V/status/1553426891285139457

throwaway4good5• 4 years ago

It appears to have landed somewhere in the Indian ocean.

r7214• 4 years ago

US: "113E 3N"

https://twitter.com/planet4589/status/1553438866203443207

China: "119.0E 9.1N"

https://twitter.com/planet4589/status/1553444872237027329

CZ5B (Chinese rocket) Reentry Prediction

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