Wentian Long March 5B Core Stage Reentry Update and Discussion Thread

[Codraroll]

3 hours ago, kerbiloid said:

Maybe, after bargaining with the local villagers in their market, everyone would be doing that, too.

There's a simple way to find out, namely by asking: "Are they?"

After all, a fair few countries are launching spacecraft over land. What happens downrange of those places? My knowledge is limited in that area, but I can't remember many reports of stuff falling down on people. Granted, those inland launch sites tend to be surrounded by vast amounts of pretty much nothing and similar amounts of secrecy, so it could be that similarly indiscriminate rocket dropping has occurred elsewhere, but with fewer houses in the way nobody has been hit (or been able to tell the world about it).

[SunlitZelkova]

1 hour ago, Codraroll said:

There's a simple way to find out, namely by asking: "Are they?"

After all, a fair few countries are launching spacecraft over land. What happens downrange of those places? My knowledge is limited in that area, but I can't remember many reports of stuff falling down on people. Granted, those inland launch sites tend to be surrounded by vast amounts of pretty much nothing and similar amounts of secrecy, so it could be that similarly indiscriminate rocket dropping has occurred elsewhere, but with fewer houses in the way nobody has been hit (or been able to tell the world about it).

Spent Soyuz boosters are known to appear on farms down range-

-while the exhaust has caused health problems. Across the pole, effects have even been alleged from production facilities in the US interior- https://www.space.com/663-reports-outline-rocket-fuel-health-concerns-kazakhstan.html

But it could be argued that all of this is no different than POL leaking from a military base or V-22s dropping aircraft parts on kindergartens. It’s just what you get no matter what for going to space, like how you get those other effects no matter what as a price of having a strong defence.

Edited July 28, 2022 by SunlitZelkova

[steve9728]

Rocket version trolly problem: throw the boosters into somewhere 'mountains disguised as provinces', or let the rocket take the empty boosters few more seconds throw them into the pacific and let the whole world accuse you of polluting the sea, or go south to southern Asia or north to Mongolia and RU or west to middle Asia: throw them to another countries. It's morally questionable whatever you choose, so let's choose one that has relatively less impact.

There is a population distribution line between the east and west of China: the Heihe-Tengchong line. So, every rocket launch except from Wenchang, the Hainan Island at south of China, when they go East all inevitably go to the right of the line.

Use technology to solve the problems of technology and development to solve the problems that development brings. The technology for the controlled return of related rocket wrecks is developing and some of them even already being done by CNSA. Give them some time, after all, China's space development has only been going on for thirty years since it properly started in the 90s.

Spoiler

Liquid hydrogen and oxygen rockets are the future of the mankind!

Edited July 28, 2022 by steve9728

[wumpus]

5 hours ago, SunlitZelkova said:

Spent Soyuz boosters are known to appear on farms down range-

-while the exhaust has caused health problems. Across the pole, effects have even been alleged from production facilities in the US interior- https://www.space.com/663-reports-outline-rocket-fuel-health-concerns-kazakhstan.html

But it could be argued that all of this is no different than POL leaking from a military base or V-22s dropping aircraft parts on kindergartens. It’s just what you get no matter what for going to space, like how you get those other effects no matter what as a price of having a strong defence.

Farming the land between Baikonur and  just north of China?  Gotta be tough to do that.

The health problems are vastly more likely to be thanks to the Proton (UDMH) vs. the Soyuz (kerolox).  Your links references "perchlorates" which sounds like an important part of US launches (solid rocket motors) which are heavily used by Orbital (Minotaur) and (RSN) the SLS.  Do Russians even use SRB mini-boosters wrapped around the boosters like Delta or something?  I think India might mix SRB stages with hypergolic stages, but I doubt it adds up to as much atmospheric pollutants as the American launches.

[steve9728]

2 hours ago, wumpus said:

Farming the land between Baikonur and  just north of China?  Gotta be tough to do that.

Don't know about how the agriculture be like in middle Asia but in Xinjiang, at the same latitude as Baikonur, we have cotton and a variety of literally outrageously sweet fruits. The Inner Mongolia region is mainly grazing and is home to the launch site for manned spacecrafts: Jiu Quan Launch Center. And as for the north-eastern part of China at the same latitude to the east, man it is one of China's granaries.

Besides of the population distribution line, there also have something called 'The three steps of China's terrain': The highest one is the Tibetan plateau, with an average altitude of 3,000 to 4,000 metres. There is no need to discuss it here as no rocket would pass through here in normal conditions. The lowest one is the coastal provinces which have vast plains. Meanwhile China's economic centre of gravity and population distribution are mostly located in these places. Which means there are the places we should avoid. The middle 'step', on the other hand, is littered with hills and mountains, with occasional basins (such as the Sichuan Basin) and some small areas of plain in between, but the main terrain is still dominated by various mountain ranges. So, if we need to throw something, the plateau we won't passing by, the coastal provinces we need to avoid, so we only have two options: the mountains or sea.

[SunlitZelkova]

4 hours ago, wumpus said:

The health problems are vastly more likely to be thanks to the Proton (UDMH) vs. the Soyuz (kerolox).  Your links references "perchlorates" which sounds like an important part of US launches (solid rocket motors) which are heavily used by Orbital (Minotaur) and (RSN) the SLS.  Do Russians even use SRB mini-boosters wrapped around the boosters like Delta or something?  I think India might mix SRB stages with hypergolic stages, but I doubt it adds up to as much atmospheric pollutants as the American launches.

I was not saying the effects are equal, merely that they exist in some form everywhere.

The perchlorate relate to the US only, not Kazakhstan.

I’ve done a little more reading and Proton indeed seems to be the source of the problem.

[steve9728]

For a more easier way to understand here’s the map:

I point out the four launch center approximately location on the map. The left of the red line is the plateau, the ‘first step’. And the right of the yellow line is the ‘third step’. At top right of the Xichang is the Sichuan Basin. Unlike the US’s privileged geographical location, China often really has no choice.

Edited July 28, 2022 by steve9728

[Codraroll]

10 hours ago, SunlitZelkova said:

Spent Soyuz boosters are known to appear on farms down range-

Yeah, I was suspecting there could be similar issues surrounding Baikonur, but with so few people around, the same doctrine of indiscriminately discarding rocket stages would result in more acceptably low risks of somebody getting hit. The problem, as such, is not so much "people in the way" as "enough people in the way that discarded rocket stages will land near them quite often".

Edited July 28, 2022 by Codraroll

[tater]

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

 

[kerbiloid]

Before whining and mourning the terrible fate of the Kazakhstan farmers, one should also have a look in wiki.

US: 333 mln humans on 9.5 mln km².
KZ: 19 mln on 2.7 mln km².

It takes much longer for a rocket stage to find available farm to fall there in KZ than in US.

Also one should realize that in KZ there are no or few such family farms like the US got used to.
It was a large nomad pasture, then it was divided between collective farms which arre much huger that the American next-door farmers can imagine.

[sevenperforce]

Latest prediction is at 2:05 EST +/- 5 hours, which gives us a meaningfully narrowed ground track.

https://www.tiktok.com/t/ZTRDq4Tf5/

I estimate odds of impact over the USA at 2.8% and odds of land impact generally at 24.8%.

Edited July 29, 2022 by sevenperforce

[steve9728]

Spoiler

I would put my bet on Indian Ocean

[tater]

 

[kerbiloid]

Previously.

https://www.theguardian.com/us-news/2021/oct/08/us-navy-nuclear-submarine-strikes-submerged-object-in-south-china-sea-uss-connecticut

UFlyingO became USubmergedO.

Let's just follow the US submarine schedule to know exactly.

[SunlitZelkova]

22 minutes ago, kerbiloid said:

Previously.

https://www.theguardian.com/us-news/2021/oct/08/us-navy-nuclear-submarine-strikes-submerged-object-in-south-china-sea-uss-connecticut

UFlyingO became USubmergedO.

Let's just follow the US submarine schedule to know exactly.

This has already been determined to be an uncharted underwater mountain.

It’s a good lesson in why hydrography and oceanography is so important in military operations.

[kerbiloid]

46 minutes ago, SunlitZelkova said:

This has already been determined to be an uncharted underwater mountain.

One more will grow soon.

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

The part in ru wiki I like the best:

Quote

The fall of the Chinese station Tiangong-1 in 2018 in this area turned out to be accidental, as its deorbit was uncontrollable.

Great Pacific Attractor.
Attracts the crafts even from orbit.
 

[SunlitZelkova]

4 hours ago, kerbiloid said:

Great Pacific Attractor.
Attracts the crafts even from orbit.

It does make up 30% of the Earth’s surface after all.

[tater]

 

Slight variant:

 

[tater]

 

 

[tater]

 

 

Edited July 30, 2022 by tater

[sevenperforce]

My friends in Texas will be disappointed.

[steve9728]

 

[steve9728]

CMS official Weibo: At 00:55 Beijing time on 31 July 2022, the remnants of the upper stage of the CZ-5B Y3 rocket have re-entered the atmosphere. The landing area is in the sea around 119.0°E, 9.1°N, and most of the wreckage was destroyed by ablation during the re-entry process.

I measured about 58 to 60km or so from the nearest land.

Edited July 30, 2022 by steve9728

[kerbiloid]

Missed.

[SunlitZelkova]

Another happy landing!