I like the interstellar life theory for it's optimism; on a scale of Arachnids to Monoliths I feel the tone is on the higher end of that. I hope that we do 'something' with the opportunity these sol interlopers present humanity, even if it is just doing science to weird rock moving really fast. That would be something everyone can get behind.
It makes sense to me that we entertain the possibility that the universe is teeming with life. However, what I find disconcerting is that although I agree with Loeb's views regarding scientists taking an unwarranted humancentric perspective of astrobiology, the possibility that Oumuamua is artificial means that we have to pick up another humancentric perspective based upon the vanishingly small possibility that our detecting Oumuamua was by chance alone.
I'd like to kick it to our reporter in the field, kleinbl00: Is this Rama?
If it is we get two more strikes at bat: In all seriousness, let's take a whack at the Drake equation, based on what we know. Your most optimistic values put living galactic civilizations a good 3,000LY apart; your most pessimistic (but reasonable) put it at 5,000LY or so. Of course, Drake was justifying time on the Greenbank Observatory and fuckin' hell man, I leave it to the physicists among us to calculate how much is left of I Love Lucy after traveling spherically for "light years." Technically 'Oumuamua came out of Vega but back then, Vega was somewhere else. More technically it came out of Carina but if that's so, it left 45 million years ago. So look. For years I pursued rights to The Fourth Profession by Larry Niven, despite the fact that it's a deeply misogynistic story (doesn't have to be). Fundamental premise is this - an alien walks into a bar. Turns out he's a trader and he's decided alcohol is awesome. The aliens wanna trade with Earth but they need a launch laser. If Earth builds a launch laser, the aliens scoot along to their next destination with ideas and goods in tow. If Earth doesn't build a launch laser they make the sun go nova to scoot their solar sail along the way they need it to because fuckin' hell if you can't build a launch laser to their specifications you're just an animal anyway so fuck off. It's an awesome story and we should do a scificlub on it. But it makes that whole Eta Carinae thing pretty entertaining - presume the 'Oumuamuans caused Eta Carinae to go nova so they could hustle along and only got here now - Eta Carinae went nova to our eyes in 1837 but it's 7500 light years away so that means the 'Oumuamuans would only have to be traveling at mmmmmmost of the speed of light and have now slowed down to ballistic for a gravity slingshot and assessed that there's nothing to trade with down here so they're getting out to a reasonable distance before starhammering Sol and WE'RE ALL FUKT More Niven/Pournelle: Setup of Mote in God's Eye is we're an interstellar civilization with an outpost out past the Coalsack Nebula and one of our outposts has fallen to feudalism to the point of tapestries on castle walls or some dumb shit like that and there's a big bright star that used to be red and is now white and lo and behold we discover that's 'cuz this civilization was pointing a launch laser at us and their ship shows up one fine day and we say "yippee let's go visit" and discover the society is cyclical because overpopulation causes them to fall into barbarism and they all worship this trickster legend named "Crazy Eddie" because this is, after all, a Niven/Pournelle who are/were fuckin' weird dudes, lemme tell ya. What's awesome about Mote in God's Eye is the whole "whoa this star is no longer red" trope which they fuckin' could have made about Earth because dollars to donuts the idea came from the fact that Burnham's Celestial Guide talks about how Sirius was red in legend but it's mmmmaybe "wine dark sea" bullshit. Unfortunately Vega is in pretty much the exact opposite direction. There's a lot of "ignore the messenger get fukt" legend in human history which we're definitely leaning into here. But I mean... would you rather explore what probably is or what maybe is? Progress is made on the maybes. It's probably a rock - we all know this. But what if it's not? What scientific advancement did we really get out of Apollo? Exploration is proxy warfare, always has been; let's get fucking exploring again, dammit.And on far-off Earth, Dr. Carlisle Perera had as yet told no one how he had wakened from a restless sleep with the message from his subconscious still echoing in his brain: The Ramans do everything in threes.
Amen. However, the physical improbabilities you point out make me take the thought above further, to a no less disconcerting place... Given the difficulty in leaving a physical clue at the appropriate time and place, I then start to entertain the even more humancentric, but more reasonable(?) possibility that it was dropped in by development.
Ever read The Big Front Yard by Clifford Simak? Basic premise is a Yankee trader and handyman ends up housing a stranded crew of rat-sized aliens who use his handyman horde to open a wormhole in his basement so they can get back home (they convert a TV he's working on to color as payment). He hops a scooter and checks out the environment and engages the Earth in interstellar trade because apparently we're the only civilization thus far to come up with colored paint. There was another story in Analog back in the late '80s, whose author and title I have long since forgotten, that posited aliens have been among us for decades or centuries and primarily hang around to export intellectual property. The hypothesis put forth is that most any number of planets will come up with a "rabbit" as there are only so many stellar ecologies, which means there are only so many metabolisms possible, which means there's only a limited range of paradigms for life because hell, we see plenty of examples of parallel evolution on this planet why presume any other would be different. On the other hand, there's only one "wascally wabbit." The circumstances and coincidences that led to the creation of Bugs Bunny make him a much more valuable commodity than "rabbit" or, certainly, "water." Scientific American had an exobiologist go crazy one time and she basically argued that there's like four or five predominant "plant" metabolisms, of which chlorophyll is one, so you could bloody well look for life by looking for a handful of chemical signatures and skip all the uncertainty. Combine that with the fact that if you can skip between stellar systems with any regularity? Your resource issues are fuckin' solved, man. The amount of stuff in the universe nobody cares about compared to the amount of stuff people are living on? We could have reavers from Alpha Centauri strip-mining the asteroid belt and could we really give a shit? Especially if they gave us a copy of Cold Fusion for Dummies and said "go away kid ya bother me?" I'm left with the fundamental belief that getting from star to star is a real bitch and takes a really long time but we're a lot more likely to see a probe than we are to see alien soap operas.