Life signs, Mr. Spock?
Scan for life signs Mr. Spock.
The closest we have in our modern age is the science of astronomy which incidentally is far past looking for just visible light. Astronomers focus on sensing energy. Every thing in the universe gives off some sort of energy. NASA has devices sensitive enough to detect the smallest fractions of a watt emitted from Voyager 1 probe, now in interstellar space.
The main thing to remember is there is a difference between active sensors and passive sensors but they are both designed to detect energy in all its various forms. There are also two main functions for sensors in space, first to navigate by which a starship will locate its position in space and time [because Einstein] relative to where the starship is supposed to be, and second to track objects in space that are not the star ship.
So now we’ll help Spock perform a scan for life signs.
A living thing moves. Even when holding still, something alive must ventilate, circulate, digest, and probably many other things my biologically inclined ex-wife who is in medical school could list. That would be the easy low hanging fruit I think a scan for life signs would go for: patterns of movement consistent with life.
Of course if you’re searching a jungle world from orbit like Luke Skywalker searching Dagoba for a Jedi master, how’re you gonna differentiate the specific life form you need from all the trees, snakes, lizards, and robot spewing swimming swamp carnivores?
I remember nearly thirty years ago finding a Popular Science magazine with an article describing 101 uses for a miniature radar on a computer chip. The author stopped at one hundred and one because of a deadline, not because that’s all he or she could think of. Though there are hundreds if not thousands of useful things you could do with a sensor like that, the author correctly identified the bottleneck here in processing the data to reveal what exactly you are looking for, such as a heartbeat, or gaseous intestinal movement, which for some reason as I get older I have pretty regularly. So I suppose Mr. Spock might find me easy to find amidst all the Klingons. Blessings in disguise.
In any case in our current surveillance state, we have the sensors tracking us by face and clothes. And systems that watch an entire city from the air to having a Gorgon-like perspective on everything in and around the surveillance area. Don’t know if it’s possible to process that much data all at once, but with a godly perspective, you can certainly focus temporall on any part of the city you like, rewinding forwards or backwards in time to track specific people and combining the data with other scanning data for a more details than most sci fi writers imagine.
Wow, somehow we ended down the rabbit hole of ethical surveillance when what I really wanted to know was how Mr. Spock actually scans for life signs. I'll put some of this kind of stuff in the star ship blueprints I design because I think the technology is cool, even if our current world creeps me out about it.