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Comment by mecsred | Hacker News Reader

Did you see the size of the pieces they found? Do you believe junk the size of a car door falling at terminal velocity on a populated area is a risk "so small as to be unmeasurable"?

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The popular theory on why they've survived the trip down even though that doesn't fit the modeling from NASA and SpaceX is that their terminal velocity is very low.

For practical purposes does this matter? There is a lot of range between lethal and burns up on re-entry speeds for a ping pong table sized piece of debris.

Then they should improve the modeling, as a start

Amazing insight!

The risk of that debris falling from outer space and hitting a human is indeed incredibly small.

I'm not sure how you can say otherwise. Nobody's ever been hit by one, right?

The point of the article is that the frequency of launches is increasing, and the frequency at which pieces are surviving re-entry is increasing. I don’t think past performance is necessarily indicative of the future here.

It's not increasing, though. The number of launches to the space station has been relatively constant for the last 30 years or so. And it's only those launches that have this problem. The other ~100 launches or so SpaceX does each year don't.

It can still damage property. I'd love to see how you can handle suing a corporation from another country when you could barely pay your mortgage and now your house is gone, and you forgot to get space debris insurance.

Just because nobody dies, doesn't mean these things can't have dramatic consequences.

It's not only about hitting a human. Of course you can say the risk is small if you pick the smallest target? Houses, roads, barns, gas stations, and infrastructure makes up a small but relevant part of the land area here. We already have examples of space junk hitting houses, and examples of large junk than expected touching down. If we continue business as is and keep scaling up rocket launches, the risk just keeps increasing until property starts getting damaged. Is it a huge risk? No it's a manageable one. But definitely not a negligible one.

> on a populated area

Nice random qualifier there. The debris is falling over the entire earth, this one had bad luck enough to be noticed.

So yes, the risk is pretty much negligible

The article also mentions pieces of the same Crew Dragon mission landing on the roof of a house in North Carolina. Pieces of a non Crew Dragon mission going through a roof, and floor of a house in Florida.

So no, the risk isn’t negligible.

The Florida incident wasn't from Crew Dragon, it was "trash" released directly from the ISS:

https://www.nbcnews.com/science/space/nasa-space-station-deb...

Oh you’re right. I updated my comment to reflect that so as to not spread misinformation. That said the point stands. ISS junk hitting you will cause just as much damage as SpaceX junk.

Why do you think that qualifier is random? There's very little risk when things hit the ocean, it's a non populated area. That's why we do launches over it. In a populated area, there are things like houses and roads which can be hit, and cause a lot of problems. I really don't see how people can think it's "negligible" when we already have space junk hitting houses, and the pieces are getting larger. That sounds like... Negligence to me.

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