(July 14, 2025 at 9:38 pm)Ravenshire Wrote:(July 14, 2025 at 8:59 pm)Thumpalumpacus Wrote: I don't think the point is that putative aliens may have already detected us at 200 ly, I think the point is that they may well do so going forward. Because if their tech is sufficiently advanced, these signals will be available at least from the 1950s (and the advent of NORAD or its Soviet counterpart) up through today. Even that bubble, 140 ly across, encompasses what is clearly a lot of planets suitable for life even if we haven't found any life itself so far.
It should be remembered too that reception is a bit easier than transmission.
Fair enough, but there's also this:
If you threw a dart at the map of the Milky Way, and wherever that dart landed is where an advanced alien species resides, there would be a cosmically small probability that they live close enough to be aware of our existence. Even if you threw 100 darts, it's a near certainty that none would land in the little blue bubble of our radio waves.
A 200 ly bubble, while it is a mind bendingly large volume of space at human scale, is a mere rounding error at the galactic scale.
Absolutely agreed, but these radio waves aren't darts flung out at random. NORAD emissions, which are 24/7, are thrown all over the sky. If there's a capable civilization with 70 or so lys, their reception is likely, assuming that capability is actually in place. And that bubble will only grow with time.
Especially nowadays, there's a constant emission pattern we give off that would provide any other technological species decent baseline and therefore insight. Whether there's any civilization in reach and capable is clearly not evidenced at all -- but if they're there, we can be analyzed.