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the_real_cher

Good point. The chances are truly out of this world.

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> Good point. The chances are truly out of this world.

all the chances that are out of this world are chances of not being hit.

problem is, fully all the chances of being hit are on this world.

"if it wasn't for bad luck, I wouldn't have no luck at all." - Cousin Joe

Yet possible as proven here. Hitting a home is bad enough.

The chances will probably increase the more space debris is handled in this way.

Also, tell the family they just have “bad luck”.

They're making space puns

Homes are much larger than people and people are always in their homes. And even if you were home it’s not like it would 100% penetrate a floor you’re on or wall or whatever.

The linked Twitter post above contains at least one picture of a fully penetrated floor.

US houses are notoriously not as well built as in other places in the world. Where I live at the moment for instance is concrete all around, including the roof. I would be surprised if this falling on it would do anything at all and surely wouldn’t penetrate.

Are you sure about that? It's not literally Rods From the Gods but it's a high density high heat resistance metal chunk, going very fast.

I’m not certain, no. But I’d be curious to see. In my building, each floor is around 20–30 cm thick concrete.

If a barrier can stop a .50 cal BMG, then it should be sufficient to stop space debris. 20-30 cm of concrete should be enough.

I have no idea how fast it was going when it hit, but as it is more than 10x the mass of a 50 cal, I wouldn't rely on the assumption that protection from the latter is also protection from the former.

>US houses are notoriously not as well built as in other places in the world.

I bet you could count on one hand the number of places in the world that, on average, have higher building standards than the US.

>Where I live at the moment for instance is concrete all around, including the roof.

Is the ability to stop space junk your measure here? Are we building homes or bunkers?

Where I live, the common construction for houses is to have reinforced concrete slabs as the floors and ceilings, with the walls being brick except for the load-bearing reinforced concrete columns. The ceramic tiled roof (when there's one) goes above the reinforced concrete ceiling. More than once, I've read about accidents in which Brazilians fell (sometimes to their death) through the ceiling of a USA home, and that's because we simply don't expect the ceiling to be so fragile; our intuition is that the ceiling is as strong as the floor, and that we can walk normally over it.

To those from countries with a similar building culture, USA houses feel really fragile; for instance, what do you mean you can punch a hole in a room's internal wall? We expect these walls to be made of brick.

Sure, but that concrete would break up in case of earthquake and kill a lot of people with debris. US houses are much safer in case of earthquake which is much more likely than space debris.

There are places in the US that that type of build is the norm.

Beyond that, “better built” in what sense? I’ve lived in the places that are built like bunkers (literally; Guam builds for direct typhoon hits). They are fine, but aren’t built for earthquakes, energy efficiency, or any other metric that’s more relevant in other parts of the world.

> Also, tell the family they just have “bad luck”.

It's not wrong, though.

The Earth's surface is slightly over 500 million km².

Let's say that something landing within a 10m radius of you represents a hit. That radius is about 314 m², or 0,000314 km²

If my math doesn't fail me, if we partition the globe into discrete areas equivalent to that 10m radius, the odds of something landing on your area would be around 1 in 10^12.

That's the chance of one specific person being hit. But I think you'd want to calculate the chance of any one person being "hit", which is roughly ten billion times higher than that, and uncomfortably likely (if people were actually 10m wide).

>(if people were actually 10m wide).

Apparently, we're working on that.

doesnt the orbit shadow vastly reduce surface area to a few thin overlapping strips?

Whose orbit?

the orbit/trajectory of the vessel the junk originally stemmed from

Except that neither human nor satellite distribution is even across the global surface, and we actually tend to put our satellites above the human-populated areas so that they can service those humans.

Including the nigh-unpopulated polar regions would massively skew the probabilities, for instance, especially since most satellites aren't in polar orbits either. It's still an infinitesimally small likelihood of being hit by one, of course.

> The chances will probably increase the more space debris is handled in this way.

The more stuff falls the more the models will be fine tuned to figure out how to re-enter stuff to completely burn it.

According to Clark R. Chapman (2007) [1], the "Odds of Dying in the U.S. from Selected Causes in a Human Lifetime" have Regional Asteroid/Comet Impact as 1 in 1,600,000, while the Odds of winning the PowerBall are 1 in 195,249,054.

[1] https://www2.tulane.edu/~sanelson/Natural_Disasters/impacts....

I think the odds of dying from asteroid impact come from global collapse of agriculture, not the thing falling near you.

Most asteroids aren't the Earth ending kind.

> Every day, Earth is bombarded with more than 100 tons of dust and sand-sized particles.

https://www.nasa.gov/solar-system/asteroids/asteroid-fast-fa...

Yes, but an asteroid doesn't have to be earth-ending to ruin agriculture for a year. This is similar to the civilizational threat of volcanic supereruptions.

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