CONTRARY BRIN: Galactic matters & supermassive black holes!

Been taking a break from the tsunami of “AI stuff” – pokes and pods about the Chat GPT and the absurd “moratorium petition” and such… and also from the USA’s insane political meltdown. At a time when there are so many indicators that our confidence should be rising, not falling.

So… instead let’s pause all that and take a break for science… especially spaaaaaaace.

Like wow. Let’s start with an M dwarf sun with two Earth-sized worlds orbiting in the potentially habitable ‘goldilocks belt.’

Indeed, roughly half of the galaxy’s sunlike stars may host rocky worlds in habitable zones where liquid water could pool or flow over the planets’ surfaces, according to one appraisal of Kepler mission data. By just that measure, the closest such world is probably within 20 light-years, and four should be within 33 light-years. Only, that doesn’t even include the vastly bigger pool of ice-roofed ocean worlds like Europa that may exist near almost any star you see in the sky. Including those a mere 4 or 5 l.y. away.

How many alien civilizations are out there? “Of course, many factors determine whether a world in the habitable zone is truly friendly for life. Planetary characteristics such as magnetic fields, atmospheres, water content, and plate tectonics all play a role, and those are difficult to observe on small, faraway worlds,” writes Nadia Drake in National Geographic.

Expanding the search? It’s been almost 8 years since NASA scientists held a news conference predicting discovery of alien life within a decade. At least spectral signs of planetary atmospheres likely altered by biological activity, as our planet has been. While waiting for that milestone, what teams have appeared to accomplish is to survey 100,000 galaxies for the most blatant signs of total takeover by unrestrained techno ambition of super civilizations, of the sort seen in some garish sci fi. There may still be some Dyson Spheres and such, but not on a scale that would alter the smeared stellar light output of whole galaxies. So… there’s an upper bound, it seems.

Disappointed? Wow, aren’t you the ambitious one…