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Comment by Zenst | Hacker News Reader

What type of pillow can stop a meteorite is what I'm wondering. Sure the roof may of slowed it enough but for it to still be intact from that and at that size, it would of been dense to make it that far without breaking up or burning up and I'd of expected a more substantial roof would be needed to slow it. Then the final detail, It would still be pretty darn hot.

So I'm somewhat sceptical.

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I won't make numerical estimates here, but we can consider that:

  - the piece of meteorite had already achieved terminal velocity,

  - most of the remaining energy was lost on the collision with the layers of the roof and

  - final collision was dampened by the pillow, mattress foam and bed structure.

By the size of of the object on the photograph, if it has approximately the same density of earth stones, the story seems 100% believable.

>What type of pillow can stop a meteorite

The kind that has a roof, ceiling and maybe a few walls between it and the meteorite.

This NASA document explains very nicely how a series of thin shields can provide more protection than one much thicker shield layer. Of course, the velocity is much lower once in the atmosphere.

https://hvit.jsc.nasa.gov/shield-development/

I suspect they're trading an obscene amount of space to save weight (because space). There's a reason (the reason being they tested this stuff 1.5 centuries ago) pretty much no armored vehicle or vessel uses armor with empty spaces in between.

It’s called “spaced armor” and there’s a whole wikipedia article detailing its use in the last century of tank design.

Army wants to save weight too btw, they do fly these things in after all.

https://en.m.wikipedia.org/wiki/Spaced_armour

Not only that, but you get better fuel efficiency, better acceleration etc.

You would be surprised: https://below-the-turret-ring.blogspot.com/2016/03/chobham-a...

Sounds like it may have hit the mattress before rolling between the pillows, and the photo and title are mildly sensationalizing with hitting the pillow directly.

> “…I rolled back one of the two pillows I'd been sleeping on and in between them was the meteorite."

As I understand it most meteorites, especially small ones, are cool when they hit the earth.

https://planetary.msfc.nasa.gov/Meteorites_and_Craters.html

I'm really kinda hoping it was a MyPillow so that my afternoon local radio ads turn into METEORITE PROTECTION

Assuming meteors can have any initial size, speed, and entry angle, there must be some sets of those initial values such that a remaining meteorite of the size seen in these photos could go through a roof and land on a bed. It doesn't seem possible that there would be any step function where if it doesn't burn up completely and can make it through a roof it must be going fast enough to also go through a pillow.

“Aww, I loosened it for ya!” - Roof

(Like the wide opening a jar of pickles her husband couldn’t)

also possibly quite hot from recent interactions with the atmosphere

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