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New Long March 5B Uncontrolled Reentry Tracked by Aerospace's Experts

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Re: New Long March 5B Uncontrolled Reentry Tracked by Aerospace's Experts

#81

Post by cycrutchfield »

FpUser wrote: post #52
cycrutchfield wrote: post #10

Earlier quoted context omitted.

Ah, the good old “whatabout the US did it 50 years ago therefore we can do it today”. Also used to justify all sorts of atrocities, imperialism, IP theft, etc.

>"the US did it 50 years ago therefore we can do it today" The US / or other countries for that matter "did it XXX years ago" to advance their goals and get more prosperous at the expense of the others. If you want to punish countries for doing similar things now it is totally ok, as long as you punish the same crimes committed earlier. The crime must be paid for. This of course will never happen so when you are tryi…

If you punish every country retroactively for crimes committed ages ago, every country would cease to exist. There is no country without blood on its hands, historically. This is like saying that you should go to jail because your grandfather jaywalked 80 years ago, which was not a crime back then but is now.

Re: New Long March 5B Uncontrolled Reentry Tracked by Aerospace's Experts

#82

Post by fwipsy »

ghufran_syed wrote: post #43
fwipsy wrote: post #42

Earlier quoted context omitted.

Let's not make generalizations about a country of 1b+ people based on one aspect of their space program. You could easily draw an equally unflattering image of the US or any other nation if you're willing to extrapolate from a single datapoint like that.

charitable interpretation: “china” = “chinese government“ in the statement you are responding to. I try to use the latter form myself when talking about nation state actions to aid people who have trouble translating from one to the other, but it doesn’t seem that hard to figure out in this case. otoh e.g. “the chinese value education highly” is a bit more ambiguous since the statement is true for both the chinese pe…

This interpretation is a little better, but I think my objections still apply.

Re: New Long March 5B Uncontrolled Reentry Tracked by Aerospace's Experts

#83

Post by tkanarsky »

tostonescon wrote: post #72

Genuinely curious - why is China doing uncontrolled reentry any different? As far as I understand it the vast majority of rockets have uncontrolled re-entry, save for spaceplanes, falcon 9, and more recently electron.

Several nuances:

"Controlled reentry" isn't necessarily synonymous with "booster recovery". Most rockets have a way to deorbit the upper stage once its job is done, either by firing the main engine retrograde, or using a small dedicated deorbit motor. By firing the motor about half an orbit before the projected reentry point, you can control exactly when and where the stage will reenter the atmosphere, hence controlled reentry.

Second, the Long March 5B is somewhat unique among rockets in that its large main stage stays with the payload all the way until orbital insertion. Most other rockets drop a large majority of their bulk long before it has enough energy to stay in orbit for any appreciable amount of time. Probably the closest comparison in this category is the space shuttle's big orange external tank, as it provides fuel for the main engines until just a hair below orbital velocity, but it's subsequently jettisoned and the orbit is completed using the shuttle's onboard thrusters.

So you have a combination of (no deorbit capability) and (big tank floating in orbit) that results in (big tank crashing down at an arbitrary location whenever it feels like coming down to earth).

Re: New Long March 5B Uncontrolled Reentry Tracked by Aerospace's Experts

#84

Post by tostonescon »

mrweasel wrote: post #76
tostonescon wrote: post #72

Genuinely curious - why is China doing uncontrolled reentry any different? As far as I understand it the vast majority of rockets have uncontrolled re-entry, save for spaceplanes, falcon 9, and more recently electron.

> As far as I understand it the vast majority of rockets have uncontrolled I don't think that's true anymore. There's a Danish radio program[1] that talked about this and apparently China is the only country/operator that still have uncontrolled reentry rocket stages. Everyone else have committed to controlled reentry. Looking that the possible places where the rocket can hit populated areas. It looks like they went…

https://www.nature.com/articles/s41550-022-01718-8

>In 2020, over 60% of launches to low Earth orbit resulted in a rocket body being abandoned in orbit

>In the USA, the Orbital Debris Mitigation Standard Practices (ODMSPs) apply to all launches and require that the risk of a casualty from a reentering rocket body is below a 1-in-10,000 threshold4. However, the US Air Force waived the ODMSP requirements for 37 of the 66 launches conducted for it between 2011 and 2018, on the basis that it would be too expensive to replace non-compliant rockets with compliant ones

I do think China's space program is more irresponsible than USA/EU launches based on some of the debris fall, but blaming uncontrolled re-entry seems like the wrong thing here

Re: New Long March 5B Uncontrolled Reentry Tracked by Aerospace's Experts

#85

Post by tgsovlerkhgsel »

dangle1 wrote: post #73
MonkeyMalarky wrote: post #67

Earlier quoted context omitted.

I'd chock it up under crass disregard for others safety. They drop boosters on their own people and don't care: https://arstechnica.com/science/2019/11/china-keeps-dropping... >China's defiance of this norm has resulted in some horrific scenes as its boosters have periodically crashed into villages.

And possibly a fairing half dropped onto a populated area from a different launch yesterday: https://twitter.com/cnspaceflight/status/1589289240776839168

"It's fine, we did tell everyone to evacuate" - I wonder how many actually evacuate / can afford to evacuate every time.

Re: New Long March 5B Uncontrolled Reentry Tracked by Aerospace's Experts

#86

Post by tgsovlerkhgsel »

fwipsy wrote: post #42
holoduke wrote: post #27

Earlier quoted context omitted.

This is China in a nutshell. They don't give a fuck about what's happening around them. Unless it Harms their economic interest. Other than that they do not have any compassion for safety, environment etc. It might change in the future, but with this crazy regime I doubt people ever gonna care about it.

Let's not make generalizations about a country of 1b+ people based on one aspect of their space program. You could easily draw an equally unflattering image of the US or any other nation if you're willing to extrapolate from a single datapoint like that.

There are plenty of other data points that line up with this one though.

Re: New Long March 5B Uncontrolled Reentry Tracked by Aerospace's Experts

#87

Post by tgsovlerkhgsel »

chihuahua wrote: post #77
supertrope wrote: post #69

Earlier quoted context omitted.

China signed the Outer Space Treaty. Your rocket your damage your bill.

But how is anyone going to collect on the bill, if China doesn't want to pay?

Just quickly and quietly paying is likely cheaper than the international incident, the "China refuses to comply with treaty" headlines, and likely resulting souring of international relations.

Re: New Long March 5B Uncontrolled Reentry Tracked by Aerospace's Experts

#88

Post by LatteLazy »

fnordpiglet wrote: post #33
LatteLazy wrote: post #24

[flagged]

I like how you squeezed a crazy conspiracy theory that’s been largely dismissed in at the end. Slick.

I don't actually think COVID was leaked from the lab. I just think that Chinas refusal to do basic food hygiene, despite multiple zoonotic diseases already arriving makes it equally criminal...

Re: New Long March 5B Uncontrolled Reentry Tracked by Aerospace's Experts

#89

Post by speedylight »

pfdietz wrote: post #75
dvt wrote: post #66

Earlier quoted context omitted.

Not according to the ESA[1], NASA[1], Portugese airspace authorities, or our captain. Or my dad, for that matter, who works for NASA (some of his projects specifically involve space debris cleanup). But thanks for your input, random internet stranger. [1] https://www.space.com/nasa-esa-space-chiefs-condemn-china-ro...

Nowhere in that rather bombastic report did I see any argument justifying altering any airline flight due to the reentry.

It may not say it directly but the implication is clear, in that uncontrolled re-entry is dangerous to anything that might cross its path, including people, infrastructure, planes, and pigeons if they’re really unlucky.

Re: New Long March 5B Uncontrolled Reentry Tracked by Aerospace's Experts

#90

Post by ch4s3 »

MichaelZuo wrote: post #80
ch4s3 wrote: post #59

Earlier quoted context omitted.

There are numerous scientists and government agencies on the record making official press releases claiming to have tracked the rocket debris to an area of Cotes d'Ivoire. There are photos in Cotes d'Ivoire of wreckage consistent with the rocket. Why do you need an "official investigation"? Who would you trust to do that? Why are you taking the word of the Chinese government?

The Verge article links to a 'local news site' afriksoir.net that looks really shady, similar to clickbait spam sites. Registered on April 9th, 2019 with GoDaddy according to WHOIS. It's top story today is just commenting on some Ivorian politican's Twitter feed https://afriksoir.net/lobognon-junte-goita-integrite-mali-jo... And it's not linked to any established West African news organization. This took me about 10…

Oh please, numerous scientists and governments tracked the Rocket debris going down over Cotes d’Ivoire. It landed somewhere there for sure. Analysts think the photo is credible. The preponderance of evidence points in a clear direction, we’re not trying to convict someone of murder here.

What do you think fell in Cotes d’Ivoire? What level of proof would be sufficient? Why are you so willing to believe the CCO line here? How have they demonstrated evidence to the contrary? If it burned up in reentry surely they have proof no? Where’s there investigation?

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