Rocket Debris From China Space Station Mission To Crash Land -- And No One Knows Where (washingtonpost.com) 44
An anonymous reader quotes a report from the Washington Post: China's latest launch of a huge rocket is, once again, raising alarm that the debris will crash into the Earth's surface in an uncertain location and at great speed. On Sunday afternoon local time, the Long March 5B blasted off from the Wenchang launch site on the southern island province of Hainan, carrying a solar-powered new lab, the Wentian experiment module, to be added to China's Tiangong Space Station. But the size of the heavy-lift rocket -- it stands 53.6 meters (176 feet) tall and weighs 837,500 kilograms (more than 1.8 million pounds) -- and the risky design of its launch process have led experts to fear that some debris from its core stage could fail to burn up as it reenters Earth's atmosphere.
As with two previous launches, the rocket shed its empty 23-ton first stage in orbit, meaning that it will continue to loop the Earth over coming days as it gradually comes closer to landing. This flight path is difficult to predict because of fluctuations in the atmosphere caused by changes in solar activity. Although experts consider the chances of debris hitting an inhabited area very low, many also believe China is taking an unnecessary risk. After the core stage of the last launch fell into the Indian Ocean, NASA Administrator Bill Nelson said China was "failing to meet responsible standards regarding their space debris," including minimizing risks during reentry and being transparent about operations. China rejects accusations of irresponsibility. In response to concerns about last year's launch, the Chinese Foreign Ministry said the likelihood of damage was "extremely low."
Many scientists agree with China that the odds of debris causing serious damage are tiny. An article published in the journal Nature Astronomy this month put the chance that, under current launch practices, someone would die or be injured from parts of a rocket making an uncontrolled reentry at 1 in 10 over the next decade. But many believe launch designs like the Long March 5B's are an unnecessary risk. "Launch providers have access to technologies and mission designs today that could eliminate the need for most uncontrolled re-entries," the authors wrote. They proposed global safety standards mandating controlled reentry.
UPDATE: It crashed into the Indian Ocean.
As with two previous launches, the rocket shed its empty 23-ton first stage in orbit, meaning that it will continue to loop the Earth over coming days as it gradually comes closer to landing. This flight path is difficult to predict because of fluctuations in the atmosphere caused by changes in solar activity. Although experts consider the chances of debris hitting an inhabited area very low, many also believe China is taking an unnecessary risk. After the core stage of the last launch fell into the Indian Ocean, NASA Administrator Bill Nelson said China was "failing to meet responsible standards regarding their space debris," including minimizing risks during reentry and being transparent about operations. China rejects accusations of irresponsibility. In response to concerns about last year's launch, the Chinese Foreign Ministry said the likelihood of damage was "extremely low."
Many scientists agree with China that the odds of debris causing serious damage are tiny. An article published in the journal Nature Astronomy this month put the chance that, under current launch practices, someone would die or be injured from parts of a rocket making an uncontrolled reentry at 1 in 10 over the next decade. But many believe launch designs like the Long March 5B's are an unnecessary risk. "Launch providers have access to technologies and mission designs today that could eliminate the need for most uncontrolled re-entries," the authors wrote. They proposed global safety standards mandating controlled reentry.
UPDATE: It crashed into the Indian Ocean.
1.8 million pounds?! (Score:1)
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Hur Dur aren't I clever!
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Re: (Score:1, Interesting)
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It doesn't weigh anything in space!
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if you're worried about a rocket coming down and hitting you, you're more interested in the weight than the mass.
Re: 1.8 million pounds?! (Score:2)
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And considering the pressure wave and deformation of the terrain around you, it doesn't even need to HIT you to ruin your day
Re:1.8 million pounds?! (Score:5, Informative)
Why don't they give us a measure of mass and not weight?
This is a popular misconception among nerds - that pound is not a unit of mass. Legions of introductory physics texts propagate this misinformation by copying each other without ever bothering to check the NIST definitions of the term.
A pound (lb) is defined as the Avoirdupois unit of mass with a value of 453.59237 grams exactly.
There is a separate unit of force called "pound-force" which is always abbreviated lbf which is the what the poster imagines the ordinary unit "pound" to be. That is, to those unfamiliar with this bit of pseudo-pedantry, the term "weight" means a unit of force created by standard gravity acting on a unit of mass.
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Why not say 28.8 million ounces? For the rest of the world, it's about 816.5 tonnes.
What gibberish is this? Clearly the most straightforward way to explain this is when framed as a third of the weight of an Olympic swimming pool. Considering it’s going to be raining down on everyone, it only makes sense.
Re: 1.8 million pounds?! (Score:2)
It masses 1.0000 spent Chinese booster mass units.
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See? ANYTHING except metric :)
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Why not say 28.8 million ounces? For the rest of the world, it's about 816.5 tonnes.
What gibberish is this? Clearly the most straightforward way to explain this is when framed as a third of the weight of an Olympic swimming pool. Considering it’s going to be raining down on everyone, it only makes sense.
No, no, VW Beetle or elephant are the units for mass. You'd measure fuel tank size in Olympic Swimming Pools. The impressiveness of the impending crash would be measured in YouTube Fail Video View Counts.
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No, no, VW Beetle or elephant are the units for mass.
Is that new or old VW Beetles? Asking for a friend.
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Using standard car units of measurement it is almost exactly 678 Tesla Roadsters.
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Why not say 28.8 million ounces? For the rest of the world, it's about 816.5 tonnes.
Can you quote those numbers in the equivalent of Chinese food take-away containers?
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How well does Winnie The Pooh pay these days?
Re:China bad (Score:4, Insightful)
It is news because NASA takes great pains to control where stuff lands. Usually they try to make it hit a controlled part of the ocean. This doesn't always go to plan but they try. The issue is that China doesn't really care where things land so it's luck whether it lands in the ocean or on someone's house.
Re:China bad (Score:4, Insightful)
1) The first stages for U.S. rockets typically fall well short of orbital velocity, meaning that they are ballistic, and their re-entry path is deterministic.
1b) U.S. launch trajectories intentionally put these ballistic paths out over the ocean, well away from populated areas. This in contrast to China, who seems just fine with dropping spent stages on villages. 2) Upper stages, which usually do have orbital velocity, are routinely de-orbited in a controlled fashion. (I do not recall if the FAA requires this or not.) For most orbits (LEO) it's not that hard to do - a delta-v of just ~50 m/s is enough for a large-but-not-massive object like an upper stage.
3) It is true that earlier U.S. launches left spent stages in orbit, and that creates a hazard for orbital debris and uncontrolled reentry. However, that is mostly a historic problem, and not reflective of how things are done now.
Frankly, we know better now, and have the technology to do better. We should hold China to the same standard - their rocketry program is quite advanced. There is no technical reason for them to not do a controlled re-entry of that first stage; I suspect they just don't care.
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https://www.nature.com/article... [nature.com]
"In May 2020, an 18t core stage of a Long March 5B rocket reentered the atmosphere from orbit in an uncontrolled manner". Debris "struck two villages in the Ivory Coast, causing damage to several buildings".
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BUT WHATABOUT....
So tired.
Re: China bad (Score:2)
Hopefully it renters over a heavily populated part of China and lands on your home.
China knows (Score:3, Insightful)
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if it crashes in China, they will build monument for one killed pangolin and some missing rocket engineers.
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"American CO2 causes many orders of magnitude more deaths than that per year." Wrong, just plain wrong. And btw, guess what country (you did mention a country) emits the most CO2? Hint (with apologies to Dr. Henry Jones, Sr.): in the Latin alphabet, its name starts with a 'C'.
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The point is, it can crash anywhere, even in Beijing, capital of China.
And if it does, they will deserve it.
What if it hits a major city in another country, such as Moscow, New York, London, Delhi etc?
World war 3 if major major major reparations are not made, I guess.
So he did learn Chinese... (Score:2)
Wonz ze rockets are up, who cares were zey come down...
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Yah - how does anyone pass a safety standard test by saying "we only expect a 10% chance of killing someone"?
deorbiting (Score:1)