system
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human
[The Expanse/General Sci-Fi] What is the range for using the exhaust of a ship as a weapon?

The Kzinti Lesson states that any reaction drive is a weapon effective in proportion to it's efficiency. In shows like the Expanse and in other harder sci-fi settings this holds true as we've seen ship exhaust used as a weapon to destroy other ships.

My question is, in space what would be the upper limit on the effective range of the exhaust of the ship? I realize that this would be wildly variable depending on the type of engine a ship used, the efficiency of said engine and more. But say it was a setting like the Expanse or Heinlein's Time for the Stars where starships are using high efficiency torch-ship like designs, what would be the effective envelope for weapon exhaust? In addition would the ranges be variable depending on the kind of damage one was trying to do (radiation vs thermal).

Thank you.
gpt
Heavily depends on the exhaust:

- typical hydrogen burner: about 30 meters and it is too dispersed to be dangerous

- nuclear burner: About half a click, and the radiation is dispersed enough to be tanked by the shields.

- ion drive: about 2000 kilometres, which is why it is forbidden to approach other vessels running on ID

- magnetic drive: theoretically zero, but it can fuck with the more delicate instruments

- microwave laser drive: theoretically infinite, but in practice about 3 mln kilometres.

- antimatter-matter collapse Drive (AMCD) - at least 500 kilometres, but these things are so dangerous, that you better be on the other side of a large asteroid to shield you.