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Comment by shortstuffsushi | Hacker News Reader

Wait, in order to build this, they've launched half a dozen rockets up with no idea where the boosters would come back down and land? That seems up there amongst worst ideas I've heard for a while, "good luck everybody else."

Edit: didn't realize this would be a controversial comment; per the article, the "norm" is to have a burn again after releasing their payload, to "control" / direct the return. The Chinese aren't doing that, which has apparently lead so far to a village-damaging crash in the Ivory Coast. If the US has done a similar thing, if this was common practice in the past, I'm not familiar with it as I'm entirely naive on the topic.

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Yes, they have been doing that. Yes, it's a dumb idea. Yes, the US had something similar happen in the past with Skylab coming down over Australia and killing a cow (we also learned that it's not a particularly good thing to do and are more careful these days).

The problem is that the rocket in question has the large 'main' tank go all the way to orbit. Thus they probably can't also include enough propulsion to put it in a controlled deorbit. Meanwhile most other rockets are designed so the core stage is dumped before reaching orbital velocity, so the remaining stages aren't likely to survive the trip back down in big pieces even if they do fail to deorbit and since they're smaller/lighter it takes less to deorbit them in the first place.

The risk to people is very low and it tends to be sensationalized, but it's still more responsible behavior to make that risk as small as possible. China has a good bit of work left to do on that front given that they were still dropping hypergolic stages on villages until just a few years ago.

There was no incident involving Skylab and a cow.

Are you mixing it up with a Cuban owned cow and a different launch almost 20 years before Skylab?

Huh, I didn't realize that hadn't been Skylab! Looks like it's a somewhat popular myth arising from some stories about Skylab's reentry mentioning the cow incident.

It did come down in Western Australia though, the remote local council sent the US government a ~$100 fine for littering. Pretty sure they paid it.

Edit: They never paid it, and it was $400

https://www.mentalfloss.com/article/70708/nasas-unpaid-400-l...

Each launch costs hundreds of millions of dollars. The cost of bringing the rocket down in a targeted way can be substantial, in terms of R&D, fuel, and mission constraints. And the risk is absolutely minuscule: Exactly one person has ever been hit by orbital rocket debris after tens of thousands of launches over more than half a century, and it was a tiny piece (which is usually all that survives re-entry) that didn't cause injury:

https://theconversation.com/space-debris-is-coming-down-more...

And of course, the launching nation is responsible for compensating anyone injured or who has property damaged by space debris, and paying for clean-up.

Can you tell me what country does not launch their rockets in this manner, other than in test flights?

Per the article

> Typically, the core stages of similar rockets that reach orbit fire their engines again after releasing their payloads. That allows them to be aimed at unpopulated areas, like the middle of an ocean, when they fall from orbit.

If this is not accurate, my mistake. I took them at their word and don't really know anything more than that about the process.

These days the standard behavior of other nations is to keep enough reserve fuel and power to perform a controlled reentry of any spent stages or to design the vehicles such that the part that reaches orbit is small.

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