We’ve actually gotten relatively clear pictures of exoplanets fairly recently. They’re still blobs, but now they have color!
But we can’t see planet surfaces yet. The most we have achieved is seeing a dark smudge in front of a light smudge.
Most planets are detected either by the star wobbling a little due to the planet pulling on it through gravity. Think a light smudge going a pixel to the left and then a pixel to the right.
Or by detecting a star getting slightly darker when a planet passes in front of it. This lets us guess the composition of the atmosphere when we filter the star light through a prisma and analyse which wavelengths of light we have a smidgen less of.
It’s amazing what we can do. But we’re still a far way away from actually seeing extrasolar planets.
entwine413@lemm.ee 2 weeks ago
TrojanRoomCoffeePot@lemmy.world 2 weeks ago
OP’s criteria is for an equal (equivalent) alien civilization.
If they were to have what we have, they would be able to detect (infer) atmospheric composition filled with the byproducts of industrialization. It’s not ideal, but IMO we’re halfway there. I can’t recall the system’s designation, but there was some hubbub about one where the Sun’s light was interrupted by some huge mass which seemed to not follow an irregular (hypothetically artificial and intelligently controlled) orbit. I can’t wait for the tech to improve, this is exciting stuff.