[Spaceships] Orion space drive: launch from underwater?

[dcarson]

Really good sensors let you detect things. Purified radioactives are rare anywhere. But large things moving underwater and thermal hot spots can be detected but unless you have a good baseline you don't know if that's industrial activity or a whales and natural thermal vents. So if they haven't been monitoring it will take a while to check all the unusual things they detect.

[Agemegos]

Originally Posted by dcarson

Really good sensors let you detect things.

That's true. And super-science sensors are in general better in that way than hard science sensors.

Purified radioactives are rare anywhere.

True. But they are also hard to detect through a hundred metres of seawater using realistic technology. They might emit neutrinos that would make it, but neutrinos are crummy for imaging with.

But large things moving underwater and thermal hot spots can be detected but unless you have a good baseline you don't know if that's industrial activity or a whales and natural thermal vents. So if they haven't been monitoring it will take a while to check all the unusual things they detect.

True. And besides — the adventure will still work if the humans can detect or even localise the industry of the subaquatic civilisation. I'm trying to present a surprise space program, not a surprise industrial civilisation.