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Massive piece of Chinese space junk slams uncontrolled into Earth's atmosphere

A Chinese Aerospace Corporation image shows the Long March 5b's launch from Wenchang launch center May 5.
A Chinese Aerospace Corporation image shows the Long March 5b's launch from Wenchang launch center May 5.
(Image: © CASC)

A 19.6-ton (17,800 kilograms) Chinese rocket slammed into our planet today (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. (Another contender he mentioned: the 2003 shuttle Columbia disaster, though that reentry did not become uncontrolled until the space shuttle was already in the atmosphere over Texas.)

In July 2019, the Chinese space station Tiangong-2 fell in a controlled descent through Earth’s atmosphere. But that 9.5-ton (8,600 kg) crash was less than half the size of today's descent, and it was guided remotely using the last of its fuel to land in a specific, remote bit of ocean. In 2018, that space station's predecessor,  the 9.3-ton (8,500 kg) Tiangong-1, fell uncontrolled (but harmlessly) into the Pacific ocean

The 18th Space Control Squadron, an Air Force space-tracking group, reported that Long March 5B reentered the atmosphere at 11:33 a.m. EST. At that time, it was just off the west coast of Africa, approaching Nouakchott, Mauritania. In the rocket's last half-hour in orbit, it passed over Hollywood, Colorado Springs and New York City's Central Park, according to McDowell.

Related: In Photos: A Look at China's space station that's crashing to Earth

"I've never seen a major reentry pass directly over so many major conurbations [metropolitan areas]!" McDowell tweeted.

The rocket's uncontrolled reentry path was largely determined by the last few days of space weather, McDowell said. Particles streaming from the sun can create drag and perturb the path of such a fast-moving piece of debris in ways that make its passage difficult to predict.

Originally published on Live Science.

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  • Star Spangled Hypocrisy
    Why is this framed as "space junk" and why is the adjective "uncontrolled" (or some closely related variant) used in so many "independently produced" Corporate State Media?

    Are we to assume that every time the US sent a Space Shuttle into orbit, that its own "space junk" did not fall "uncontrolled" to earth before "slamming into" whatever?

    Or are we to assume that "those people" have no business in "our" space?

    I would expect better from a media outlet that purports to present a "scientific", rather than jingoistic nationalist editorial perspective.
    Reply
  • Stealthbird97
    Star Spangled Hypocrisy said:
    Why is this framed as "space junk" and why is the adjective "uncontrolled" (or some closely related variant) used in so many "independently produced" Corporate State Media?

    Are we to assume that every time the US sent a Space Shuttle into orbit, that its own "space junk" did not fall "uncontrolled" to earth before "slamming into" whatever?
    To give you clarification, a controlled reentry would be one where the reentry trajectory is either physically controlled or planned to follow a specific course. In the case of shuttle launches, the solid boosters and external fuel tank would be controlled reentries as their trajectories would be essentially determined by the flight. This was done such that the solid rocket boosters could be recovered and then reused (In all but 4 instances the SRB were recovered). The External tank was not reused but instead set on a trajectory which would cause it to burn up over the Indian ocean (or pacific ocean) away from shipping lanes. Nowadays, the exemplar for a controlled reenetry is the sort of stuff space-x is doing.

    In the case of deorbiting of space-stations and satellites, a controlled reentry is usually carried out by using the remaining fuel and the thrusters to forcibly deorbit the object onto a particular trajectory away from populated areas, or in such a way to maximize the burn-up time minimizing the potential for larger debris hitting the ground.

    Where this is not possible, you are basically relying on the upper atmospheric conditions to cause the orbit decay. The exact time of reentry is difficult to predict, meaning it is difficult to predict the reentry trajectory and impact zone. This is made more complicated if the object is tumbling back to earth during a uncontrolled decent and in general the whole idea of an uncontrolled reentry is considered to be potentially dangerous and therefore, irresponsible.

    The issue is not that this piece of junk fell back to earth, but that it appears that no effort was put in to mitigating risks during the reenetry by forward planning. Uncontrolled deorbits should be avoided where possible.
    Reply
  • Star Spangled Hypocrisy
    Stealthbird97 said:
    To give you clarification, a controlled reentry would be one where the reentry trajectory is either physically controlled or planned to follow a specific course. In the case of shuttle launches, the solid boosters and external fuel tank would be controlled reentries as their trajectories would be essentially determined by the flight. This was done such that the solid rocket boosters could be recovered and then reused (In all but 4 instances the SRB were recovered). The External tank was not reused but instead set on a trajectory which would cause it to burn up over the Indian ocean (or pacific ocean) away from shipping lanes. Nowadays, the exemplar for a controlled reenetry is the sort of stuff space-x is doing.

    In the case of deorbiting of space-stations and satellites, a controlled reentry is usually carried out by using the remaining fuel and the thrusters to forcibly deorbit the object onto a particular trajectory away from populated areas, or in such a way to maximize the burn-up time minimizing the potential for larger debris hitting the ground.

    Where this is not possible, you are basically relying on the upper atmospheric conditions to cause the orbit decay. The exact time of reentry is difficult to predict, meaning it is difficult to predict the reentry trajectory and impact zone. This is made more complicated if the object is tumbling back to earth during a uncontrolled decent and in general the whole idea of an uncontrolled reentry is considered to be potentially dangerous and therefore, irresponsible.

    The issue is not that this piece of junk fell back to earth, but that it appears that no effort was put in to mitigating risks during the reenetry by forward planning. Uncontrolled deorbits should be avoided where possible.


    And yet, the US Space Shuttle flew over 150 missions, each of which involved the release and free-fall back to earth of a 40 ton external fuel tank, the uncontrolled descent of which was never "mitigated" in any way.

    The fact that the Corporate-State Media are reporting that this piece of debris "missed NYC by 15 minutes" (landing in the ocean near *Africa* it might be noted), is indicative of much more at work than what is being presented.

    Why was there no such "concern" evinced in any of 150+ Space Shuttle missions?

    Are you seriously claiming that this is any different or less "dangerous"?
    Reply
  • Star Spangled Hypocrisy
    Set the Wayback machine for 1979 Guise and Let's Blast Off!

    Compare & Contrast;


    1979:


    "Skylab was made to go up but not to come back down.The space Junk formerly known as Skylab was designed as a temporary orbiting workshop supposedly intended for "research on scientific matters, such as the effects of prolonged weightlessness on the human body." NASA eagerly sent Skylab in orbit. However, NASA was not so eager to spend the time or the effort to plot a re-entry - or to even plan for such an event, despite the admittedly temporary nature of its, shall we say, "endeavor". Devised for just a nine-year lifespan, NASA failed to build in any control or navigation mechanisms to return the Space Junk formerly known as Skylab back to terra firma. To do so would have “cost too much,” Robert Frosch, NASA administrator at the time, stated.
    This lack of planning and a fundamental ability to not care about the consequences of ones' actions led, naturally, to the uncontrolled descent of the largest piece of space-junk to ever touch down on terra-firma. Note that I stated "terra firma" as, unlike the Long March rocket boosters, Good Old Star Spangled SpaceJunk - in true American fashion - made an unscheduled arrival on the shores of Australia. No records remain whether the illegal immigrant/space junk decided to bring a passport with it as it flew in.

    Meanwhile, "Back at the Raunch" as they say in Hollywood, what do you suppose the people of the USA were doing? Lamenting the possible deaths of millions, or celebrating and turning the whole thing into a big celebratory media event?

    I'll give you two guesses and the first one's on the house:

    Naw. Just kidding. Let me save ya the effort:


    "In the United States, people tended to treat Skylab’s return as an excuse to party. Skylab parties were held all over the United States, t-shirts with big bulls-eyes printed on them and cans of Skylab repellant were sold." ( source: https://sciencenotes.org/today-in-science-history-july-11/ )
    Reply
  • jonathanb
    As you ably point out in your last post, it's been nearly half a century since the US did something so irresponsible. And the Long March did not just land harmlessly in the ocean, pieces of it rained down on villages and caused damage, but fortunately no loss of life.

    Is it unfair that the US got a bit of a pass for SkyLab? Perhaps. But that's the benefit of being one of the pioneers; there are fewer norms when you're one of the first to do something. But almost 50 years later, China needs to do better.
    Reply