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Possibly the biggest difference between detecting a ship in space as opposed to on Earth

is that there is no horizon to hide behind, except perhaps for a black hole's event horizon.

Probably one of the most popular tropes in science fiction is the idea of the stealth

or cloaked enemy vessel, station, or even planet. For today's sci-fi Sunday, I thought

we would explain why stealth in space is considered so difficult to achieve and discuss a few of the

possible workarounds to each hurdle to hiding things. As always, this will be a detailed discussion

of the topic, so if you can slip past your housemates unnoticed, go discreetly grab a drink

and a snack and settle in for a while with us. I want to emphasize, though, that under known

science the burden is high for achieving stealth and a lot of the workarounds will qualify

as what we call

Clark Tech, technologies so advanced they are indistinguishable from magic, and probably technologies

that will be fictional for a very long time, and maybe forever. With that in mind, it is a good

choice for a sci-fi Sunday, since we tend to relax how stringently we stick to known physics

compared to our regular

Thursday episodes.

We probably need to start by asking what we mean by stealth.

We are talking about hiding a spaceship from physical detection from an opponent, with roughly

...