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Full Version: Huge Chinese space junk slams uncontrolled into atmosphere (engineering discards)
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https://www.livescience.com/long-march-c...crash.html
https://qz.com/1856233/a-chinese-rocket-...rom-space/

EXCERPTS: A 19.6-ton (17,800 kilograms) Chinese rocket slammed into our planet on May 11. The bulky Long March 5B became the heaviest orbiting thing to fall uncontrolled to Earth in nearly three decades, according to Jonathan McDowell, a Harvard astrophysicist and orbital object tracker. The last time a heavier object had an uncontrolled entry was 1991, when the 43-ton (39,000 kg) Salyut-7 Soviet space station reentered the atmosphere over Argentina, McDowell wrote on Twitter. [...] "I've never seen a major reentry pass directly over so many major conurbations [metropolitan areas]!" McDowell tweeted... (MORE - details)

[...] Typically, rocket bodies that have completed their work are discarded over the open ocean or maneuvered into long-term disposal orbits where they won’t affect people or other spacecraft. China has a spotty history with this, however, frequently dropping rocket stages in populated areas near its own launch sites. In this case, the rocket’s design made things even more difficult.

Rather than using two stages, the vehicle only has a single core and four disposable boosters. That means that the rocket body that reaches orbit and then re-enters is unusually large. Normally, the larger first stage is disposed of earlier in the mission, leaving just the smaller second stage in orbit. Chinese space engineers will likely face international pressure to adjust the rocket’s flight profile to ensure future missions don’t scatter debris over other countries—in this case, the vehicle passed over New York City less than an hour before it broke back into the atmosphere... (MORE - details)
Large chunks of a Chinese rocket missed New York City by about 15 minutes
https://arstechnica.com/science/2020/05/...5-minutes/

EXCERPT: . . . The core stage is estimated to have a mass of about 21 tons, including extra fuel on board, but it's not clear how much of the rocket survived its interaction with the atmosphere. [...] The US Space Force’s 18th Space Control Squadron confirmed that the core stage re-entered Earth's atmosphere at 11:33am ET (15:33 UTC) on Monday at a location over the Atlantic Ocean. At this point, the core stage would have been at an altitude of 80km and rapidly descending toward Earth.

[...] It is perhaps worth noting that before it entered Earth's atmosphere, the core stage track passed directly over New York City. Had it reentered the atmosphere only a little bit earlier, perhaps 15 to 20 minutes, the rocket's debris could have rained down on the largest metro area in the United States.

China has previously shown a disregard for debris from its rocket launches, however. It frequently launches rockets from pads surrounded by land. This has led to debris from first and second stages falling on villages in the country. It is not clear whether future launches of the Long March 5B rocket will continue to send its core stage into an unstable orbit or if this was a one-off instance during the rocket's test flight. Certainly this will be discouraged, at the very least, by other nations.