UFOs spotted off Irish coast under investigation

Re:UFOs spotted off Irish coast under investigation by codezero on Monday November 12, 2018 @08:40PM (#18437695)

would be interesting to know the relative trajectory – would help determine if it was a known satellite reentry or on a typical orbit of debris (lots of periodic comets have well known debris trails, they form most of the "meteor showers" that happen yearly.)

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Re:UFOs spotted off Irish coast under investigation by slg on Monday November 12, 2018 @08:56PM (#18437783)

The transcript above refers to the object banking and climbing. That sounds a lot more like a secret military vehicle than falling space debris.

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Re:UFOs spotted off Irish coast under investigation by flukus on Monday November 12, 2018 @10:56PM (#18438451)

Could be one skipping off the atmosphere. Aero breaking (https://en.wikipedia.org/wiki/Aerobraking) if you want to stick with the spacecraft theory.

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Re:UFOs spotted off Irish coast under investigation by gnulinux on Monday November 12, 2018 @11:47PM (#18438668)

I'm not an astronomer but it seems unlikely to me a meteor skipping off atmosphere would be as slow as Mach 2 and not hot enough to shine red.

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Re:UFOs spotted off Irish coast under investigation by lloeki on Tuesday November 13, 2018 @05:09AM (#18439916)

What if it was perceptually at Mach 2 / distance X yet really was at Mach 20 / distance 10 * X ? (Bullshitting numbers here, but you get the point)

Angular speed across FoV is a function of distance from the object and the only thing that makes us understand that high altitude airplanes are nowhere close to a standstill is that we can infer distance from the intrinsic knowledge of the airplane size.

If all observers are close enough together we'd be unable to uncover the illusion, as that would require a widespread enough configuration.

Additionally, I question the "astronomical" attribute, especially with planes cruising at ~800kph, Mach 2 is at most 2.5 their typical speed. Concorde is hardly astronomical, and although jet fighters are not chasing for top speed anymore some of them are still able to go to such Mach factors. Now, Mach 12, that would be closing in to being astronomical (entering the order of magnitude of an ICBM descent speed).

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Re:UFOs spotted off Irish coast under investigation by tigerlily on Tuesday November 13, 2018 @02:39AM (#18439349)

I believe they call such a thing a 'bolide'

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Re:UFOs spotted off Irish coast under investigation by starbeast on Monday November 12, 2018 @11:59PM (#18438718)

Could be outgassing.

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Re:UFOs spotted off Irish coast under investigation by rbanffy on Tuesday November 13, 2018 @07:20AM (#18440403)

Or plain lift. If the object is flat when it hits the atmosphere, it may get some lift and bounce back to space.

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Re:UFOs spotted off Irish coast under investigation by speeq on Monday November 12, 2018 @11:35PM (#18438620)

Maybe it's something from the recent Rocket Lab launch?

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Re:UFOs spotted off Irish coast under investigation by gnulinux on Monday November 12, 2018 @11:44PM (#18438658)

Seems extremely unlikely air traffic control wouldn't know of it, since it's potentially a >200-casualty mistake if it hits a commercial airline.

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Re:UFOs spotted off Irish coast under investigation by Ono-Sendai on Tuesday November 13, 2018 @07:33AM (#18440451)

The rocket lab launch was south from New Zealand - and there aren't many planes flying around down there as far as I know.

I'm guessing only the final stage would still be airborne/in space once it orbited around to populated areas. And the second/final stage should be deliberately de-orbited for exactly this reason, right?

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