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by lettergram 1387 days ago
> The Main Astronomical Observatory of NAS of Ukraine conducts an independent study of unidentified phenomena in the atmosphere.

To me this sends up a couple of thoughts: (1) this sounds like a way to spy on Russia and (2) quite possibly could be technology from Russia (such as hypersonic missiles).

Then I read the speed:

> An object contrast makes it possible to estimate the distance using colourimetric methods. Phantoms are observed in the troposphere at distances up to 10 - 12 km. We estimate their size from 3 to 12 meters and speeds up to 15 km/s.

... that's 33,500 mph ... Re-entry speed from something out of the atmosphere is something like 8km/s; or 19,000 mph. Of course that generates an insane amount of heat and is still half the reportedly measured speed.

TBH it seems like a possible sampling error for the speed calculations. If we assume that to be the case, then it seems likely (if real) that these are some sort of hypersonic test craft / missile system.
2 comments
torotonnato 1387 days ago
That's what I thought too. Why not create a bit of distance to a possible reputational damage and spy on Russia at the same time too?

Not many data points, but fig. 4 (page 3) is interesting: a linear relation between luminosity and speed. For meteors should be, as intuitively expected, proportional to kinetic energy, hence quadratic.

Does this relation holds for missiles too?

EDIT: they are not related to NASA, it's in the second sentence of the abstract (ops)

...The Main Astronomical Observatory of NAS of Ukraine conducts an independent study of UAP also...

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godelski 1387 days ago
> 15 km/s

That's over mach 40 and would allow you to circumnavigate the globe in 45 minutes.

There are flight vehicles that travel mach 20+, but 40 sounds insane. Mach also isn't the best numbers to use. The HTV-2 goes Mach 20+ but that's 5.7 km/s. Granted it is 2010 technology (first flight) but it would be insane to think we've doubled the speed and are testing these vehicles. It isn't like you can fly vehicles that fly that fast secretly. They make A LOT of noise.

Measurement errors sounds like a better explanation. Especially when we have such strong evidence of other things (like tic-tac) being measurement errors.

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