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UFO over Houston?

There’s a hole in that story

A perfect Punch-Hole!
A perfect Punch-Hole!

Thanks to “CaptainsGalSeaWitch” for the above Click2Pin yesterday!

What you’re seeing is a called a punch-hole cloud, or hole-punch cloud, or fallstreak. There are lots of names for the phenomenon and it’s no coincidence that this viewer lives near Bush Airport in Humble.

These clouds are fascinating and well-studied. Sorry, this is no UFO, unless that stands for “Understood Flying Object” as in a jet airplane.

First, consider altocumulus clouds. The “alto” part references their height above the earth which is anywhere from 6,000 to 20,000 feet. I’m guessing those clouds were relatively low, probably around 10,000 feet, you know, the level where “you can now turn on your electronic devices.” The cumulus clouds, especially in January, are cold ice crystals! So that is what a jet would be flying through. Here’s another example:

from NOAA
from NOAA

As a jet flies through the air, areas of lower pressure are generated (especially at the wing). Higher pressure compresses air and lower pressure allows air to expand.

That expanding air will cool even more than the surrounding air causing the ice crystals to become even larger and HEAVIER. Those heavy ice crystals fall toward the ground, likely evaporating long before they get there, but the result is a nice big hole in the clouds!

NOAA
NOAA

In the past, these have been mistaken for a UFO, or at least a sign that one was there! Alas, they are normal, especially near airports where jets are taking off and where those altocumulus clouds are hanging out! You can read a wonderful article on this research at Earthsky right here.

And a HUGE thanks to all of you who send me Click2Pins! I appreciate the pics and so do our viewers!

Frank

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