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Object that fell from the skies identified as separation ring from a rocket

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Re: Object that fell from the skies identified as separation ring from a rocket

#41

Post by generuso »

philipwhiuk wrote: post #9
sebmellen wrote: post #8

Do we have any idea which rocket this came from?

I asked Johnathan McDowell, who tracks space objects alongside his main job working on Chandra. He's much less convinced it's from a rocket. https://bsky.app/profile/planet4589.bsky.social/post/3leq2wb... There's not any great candidates.

Jonathan is very knowledgeable and is usually right. But in this specific instance, everything points out that this is indeed a component of a rocket.

The eyewitnesses describe that the object fell with a high velocity, with a loud noise, and was hot when it landed.

The better angles in the video [1] show molten metal on the outside, and a typical aerospace bolt pattern with carefully machined pockets around the bolts.

This kind of construction is typical in rockets, for example at the top and the bottom flanges of some stages of the Indian PSLV rocket [2]

[1] https://youtu.be/Wr1t8CE1FpQ?t=60 [2] https://upload.wikimedia.org/wikipedia/commons/6/67/PSLV_C50...

Re: Object that fell from the skies identified as separation ring from a rocket

#42

Post by mapt »

cjbgkagh wrote: post #16
jamieplex wrote: post #15

Earlier quoted context omitted.

I agree with Jonathan. It seems to be a very low-tech, solid steel ring gear assembled and riveted together from 4 distinct parts. Not very aero-spacey at all...

What other industries use rivets? Wouldn’t most non-aerospace use welds?

The size and shape alone says either rocketry or a piece of a jet turbine. And lacking any obvious plane crashes nearby...

M-V (Japan) Epsilon (Japan) Athena (US) Rokot (USSR) Soyuz-U (USSR) Soyuz-FG (Russia) Simorgh (Iran) ... many more

There are a comical number of options with parts that have a diameter somewhere in the 2.3-2.7m range.

Re: Object that fell from the skies identified as separation ring from a rocket

#43

Post by teruakohatu »

ivewonyoung wrote: post #38
philipwhiuk wrote: post #9

Earlier quoted context omitted.

I asked Johnathan McDowell, who tracks space objects alongside his main job working on Chandra. He's much less convinced it's from a rocket. https://bsky.app/profile/planet4589.bsky.social/post/3leq2wb... There's not any great candidates.

Could be from something like this: https://old.reddit.com/r/nextfuckinglevel/comments/1bmpxaq/t...

That looks ridiculously dangerous, to the point I would like Captain Disillusion to let us know if it is real.

Re: Object that fell from the skies identified as separation ring from a rocket

#45

Post by hermitcrab »

rectang wrote: post #18
jamieplex wrote: post #10

Approximately 8' diameter (other commenters pointed out a more reasonable size) solid steel ring gear (riveted together from 4 parts). Doesn't look anything like a "separation ring", and certainly isn't large enough. Plus it is solid steel. I am kinda doubting the whole story at this point. No way it is from a rocket (too heavy, too low-tech, no ring gears in rocketry), and doubtful from any commercial aircraft (agai…

Could be from a concrete mixer. (Credit: rando YouTube comment.)

From that concrete mixer the Mythbuster's blew up? It took a while to come down...

Re: Object that fell from the skies identified as separation ring from a rocket

#46

Post by mkl »

buildsjets wrote: post #36
jamieplex wrote: post #10

Approximately 8' diameter (other commenters pointed out a more reasonable size) solid steel ring gear (riveted together from 4 parts). Doesn't look anything like a "separation ring", and certainly isn't large enough. Plus it is solid steel. I am kinda doubting the whole story at this point. No way it is from a rocket (too heavy, too low-tech, no ring gears in rocketry), and doubtful from any commercial aircraft (agai…

For reference, here is a ring which is believed to have come from China's Long March BuNo Y77. Note the similar scale, and similar discoloration. https://spacenews.com/india-examining-crashed-space-debris-s... I design and build all sorts of hardware relating to air-breathing (jet) propulsion, including gears. I agree with mkl. Those are not gear teeth. They have flat flanks, and no involute profile. No one makes gea…

The appearance of rust on the surface of the article's main photo suggests steel. I guess heat from reentry may lead to that appearance on other materials?

Re: Object that fell from the skies identified as separation ring from a rocket

#47

Post by Footkerchief »

jamieplex wrote: post #10

Approximately 8' diameter (other commenters pointed out a more reasonable size) solid steel ring gear (riveted together from 4 parts). Doesn't look anything like a "separation ring", and certainly isn't large enough. Plus it is solid steel. I am kinda doubting the whole story at this point. No way it is from a rocket (too heavy, too low-tech, no ring gears in rocketry), and doubtful from any commercial aircraft (agai…

2.5 m (8 ft 2 in) in diameter:

https://en.m.wikipedia.org/wiki/M-V

Re: Object that fell from the skies identified as separation ring from a rocket

#48

Post by hermitcrab »

teruakohatu wrote: post #43
ivewonyoung wrote: post #38

Earlier quoted context omitted.

Could be from something like this: https://old.reddit.com/r/nextfuckinglevel/comments/1bmpxaq/t...

That looks ridiculously dangerous, to the point I would like Captain Disillusion to let us know if it is real.

There are lots of videos of similar Thai fireworks, but I think is the largest one I've seen. Also, based on my amateur rocketry experience, this is completely feasible, if rather dangerous. 99% sure it is a real video.

I'm not sure why it makes the 'chuffing' noise though. Anyone know?

Re: Object that fell from the skies identified as separation ring from a rocket

#49

Post by buildsjets »

mkl wrote: post #46
buildsjets wrote: post #36

Earlier quoted context omitted.

For reference, here is a ring which is believed to have come from China's Long March BuNo Y77. Note the similar scale, and similar discoloration. https://spacenews.com/india-examining-crashed-space-debris-s... I design and build all sorts of hardware relating to air-breathing (jet) propulsion, including gears. I agree with mkl. Those are not gear teeth. They have flat flanks, and no involute profile. No one makes gea…

The appearance of rust on the surface of the article's main photo suggests steel. I guess heat from reentry may lead to that appearance on other materials?

Inconel looks just like that after exposure to heat, and is much more likely to have been used to build an aerospace vehicle than carbon steel. Most jet aircraft exhaust systems are made of Inconel and oxidize to a dull brown at 1200F or so. Like on this 737NG:

https://aviation.stackexchange.com/questions/90974/what-are-...

The exhausts that turn iridescent purple for a while due to heat are titanium, for example this 787. So I would suspect the debris is not titanium based on lack of heat marking.

https://www.reddit.com/r/aviation/comments/b77f5x/b787_its_s...

So if I were to guess what kind of metal it was solely based on coloration and suspected use case, I’d say Inconel.

But I wouldn’t make a guess at all, because it’s naive to assume that you can identify a type of metal based on a grainy freeze-frame of a cell phone video that has been re-encoded an unknown number of times before publication.

Re: Object that fell from the skies identified as separation ring from a rocket

#50

Post by rectang »

hermitcrab wrote: post #45
rectang wrote: post #18

Earlier quoted context omitted.

Could be from a concrete mixer. (Credit: rando YouTube comment.)

From that concrete mixer the Mythbuster's blew up? It took a while to come down...

Haha, had it been a cement mixer ring bearing, then there would have been another explanation for the reports that it fell red hot from the sky — that they were as fanciful as the reports of mysterious drones infesting New Jersey (which seem to have actually been real planes). For instance, a broken cement mixer part got dumped there and somebody made up a colorful story.

But maybe it really is Space Junk! https://www.youtube.com/watch?v=Z2dcVIEQwEE ("and now my Sally's dead...")

Proper scientific inquiry demands both an open mind and skepticism. That's why I didn't claim "it's definitely a cement mixer ring bearing" with the usual certainty of people arguing on the internet, but attempted to convey the unreliability of my source.

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