Comment by rtkwe
2 days ago
On a similar vein there's Project Lyra which is a theoretical fly-by mission of ʻOumuamua or 2I/Borisov. The proposed trajectories to catch up are pretty crazy with my favorite being the 2030 launch for a 2052 fly-by that uses Jupiter and a close Sol 10 solar radii!) gravity assist to rocket out of the solar system [0].
It will be interesting to see if we've just been missing these extra solar objects. I have doubts we'll actually do a project Lyra style fly-by though. Funding is going the opposite direction and all.
[0] http://orbitsimulator.com/BA/lyra.gif and https://i4is.org/project-lyra-a-solar-oberth-at-10-solar-rad...
I'd expect this is just the lamppost effect and we'll start seeing lots of these. It means there's no great need to chase any particular one of them, we can almost certainly wait until we're ready, then pick one that is convenient at the time.
It also means that "Oumuamua is an alien craft!" will almost certainly join in the ignoble legacy of "thinking the first instance of a new thing must be ALIENS" once we've detected hundreds of these (or more, depending on how sensitive we can get). You'd really think we'd be over this by now, but apparently not.
Please correct me if I'm wrong, but my understand of the alien craft theory specifically for Oumuamua wasn't just because the object itself was new, but that it changed acceleration [1] without apparent off gassing in a way that isn't explained by our current understanding of orbital physics for a natural object.
It's not just "New object, must be aliens!" It's "This thing doesn't fit our understanding of orbital motion for natural objects, aliens is actually a rational, if still unlikely, possible explanation."
[1] https://en.wikipedia.org/wiki/1I/%CA%BBOumuamua#Non-gravitat...
There were a number of anomalous characteristics including its shape, acceleration, rotation, origin, and reflectivity.
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The history of science is that every freaking time we look somewhere new, we find something new. It happens over, and over, and over, and over again. We have a really bad track record of predicting things in advance in new domains. The exceptions are leaping to your mind precisely because you've heard about them because they're the exceptions.
Also, to date, zero of those things have been "aliens".
So rushing to declare the first instance of what was completely obviously a new class of objects as "aliens" because it didn't behave like what we expected is not rational, because we should expect that new things don't behave like we expect. The odds that the first one of these we detect is also the one from aliens is just not a good bet.
I'd bet a tidy sum of money that in 25 years it'll simply be common knowledge that these class of objects sometimes have those characteristics because of some characteristic special to them. Probably something to do with having a lot of things that turn to gasses and exert accelerations on the object because they were never blown off by the solar wind or something because of them being in deep space for millions of years. Might be most of them, might be a small-but-respectable fraction, but I bet in hindsight this is recorded in the history books right next to "pulsars are alien beacons!" and with the exact same tone of lightly sneering contempt we hold for that now. To which I can only say to the future, let the record show we did not all think it was aliens.
Yes (a change in acceleration was reported), but even in the link you yourself provide the hypotheses are framed within standard physics, not alien technology.
The latter got more than its fair share of press because Harvard's Avi Loeb proposed it as potential evidence of ET.
He later claimed more evidence from potential spaceship bits he reckons he found from an ancient meteor, and seems to specialize in these sorts of claims. [1]
Like you say, not irrational but perhaps over-hyped by people who ought to know better...
[1]https://www.independent.co.uk/news/world/americas/avi-loeb-i...
If we ever stop being excited about the possibility that poorly understood phenomena are evidence of undiscovered intelligent life the we'll have lost a part of our humanity.
That's just bullshit. The idea that undiscovered intelligent life is a plausible explanation for such things is just the triumph of numerically illiterate wishful thinking over rational thought.
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I remember the first time I heard of that pattern of thinking. My initial reaction was "OMG, it must be aliens!"
Then I thought "now wait a minute...hold on..."
It's not so much a matter of being ready, it's a matter of what planets are where that we can get a boost out of to get those speeds. Even with a fleet of working starships and assembling something in orbit getting up the to speed of these extra solar objects practically requires some intense maneuvers near conveniently positioned and timed planets.
> It also means that
No, it doesn't mean that. What makes 'Oumuamua special is not the fact that we didn't see interstellar objects before. It's rather the fact that 'Oumuamua has highly unusual and hard to explain properties. Avi Loeb:
> ‘Oumuamua exhibited a non-gravitational acceleration of 4.92 ± 0.16 × 10^⁻6 m/s² that decreased proportionally to 1/r², where r represents the heliocentric distance, corresponding to a formal ~30 σ detection of non-gravitational acceleration (Micheli et al., 2018). The inverse-square relationship typically indicates radiation pressure or outgassing forces. However, despite extensive observations by the Spitzer Space Telescope, no carbon-based molecules, dust, or thermal emission indicative of cometary outgassing were detected (Trilling et al., 2018). Such a paradox — acceleration without observable mass loss — violates fundamental assumptions about how small bodies behave in the solar system.
> The object’s extreme geometry presented another unprecedented observation. ‘Oumuamua’s brightness varied by a factor of 10 during its 8-hour rotation period, indicating an extreme geometry with an aspect ratio exceeding 10:1 (Drahus et al., 2018; Meech et al., 2017). Such extreme elongation is unprecedented among known Solar System objects, leading to competing interpretations of either a cigar-shaped or pancake-like geometry (Belton et al., 2018; Luu et al., 2020; Mashchenko, 2019; Moro-Martín, 2019a,b; Zhang & Lin, 2020).
> More significantly, ‘Oumuamua entered the Solar System with a velocity remarkably close to the Local Standard of Rest (LSR). The object’s velocity before encountering the Solar System was within approximately 6 km/s of the local median stellar velocity and just 11 km/s from the LSR, with negligible radial and vertical Galactic motion (Mamajek, 2017). Fewer than 1 in 500 stars share such kinematics, making ‘Oumuamua’s near-stationary approach highly improbable for a naturally ejected object from a nearby star system (Loeb, 2022). Natural ejection mechanisms from planetary systems typically impart the host star’s peculiar velocity to expelled bodies, yet ‘Oumuamua appeared to originate from the most kinematically common frame of reference in our Galactic neighborhood (Loeb, 2022; Mamajek, 2017).
> The object’s rotational dynamics added another layer of complexity. ‘Oumuamua displayed non-principal axis rotation, exhibiting a tumbling motion rather than spinning around a single axis. Such a rotational state is unusual for an object that has been traveling through interstellar space for potentially billions of years, as collisions and internal friction should have damped its motion to simple rotation (Belton et al., 2018; Fraser et al., 2018).
> Finally, the object’s slightly red color differed from both typical comets and asteroids. Its spectral properties showed no absorption features that would indicate specific mineral compositions, making it difficult to determine its definite surface composition (Jewitt et al., 2017; Ye et al., 2017). This spectral ambiguity prevented researchers from determining surface composition through standard techniques, leaving the object’s fundamental nature — rocky, icy, or something else entirely — unresolved.
https://avi-loeb.medium.com/scientific-paradigm-resistance-e...
Avi Loeb got trucks mixed up with aliens, then proudly announced he'd found a chunk of alien metal in the ocean based on that mistake.
https://news.climate.columbia.edu/2024/04/09/was-it-an-alien...
> The signals consisted of so-called Rayleigh waves, high-frequency motions that travel on or just under the surface, and die out quickly as they radiate from their source. These can be generated by earthquakes, but also by human activities, including explosions, electrical signals and vehicles. The sources of these ones seemed to be moving, not stationary. Moreover, they appeared in a definite pattern: several per hour, almost invariably between 5am and 11pm local time.
> The team checked a Google Earth map showing the seismometer and its environs. It was just off the main road to the harbor, near the Manus Navy Health Center. The center seemed to be a locus of activity, with the signals moving back and forth from it, southwest to north―the same orientation as the road. Ekström’s conclusion: the seismicity was coming from trucks bumping along the irregular surface of the road, mostly in daytime, stopping at the health center to deliver or pick up people or supplies, then going back where they came from. That included the purported tremor from the meteor explosion.
https://www.independent.co.uk/news/world/americas/avi-loeb-i...
"Fewer than 1 in 500 stars share such kinematics" means 200+ million in our little galaxy alone.
Solar Oberth manuever FTW! :D
The High Frontier board game from Phil Eklund even has it as a valid option on its orbital map of the Solar system. :)
A ten solar radii oberth maneuver too! Which is only slightly farther than the Parker Solar probe got (3.8 million miles vs ~4.3 million for that Lyra proposal)
Rendezvous with one of these would be a good use for a NERVA-type nuclear engine (upper stage, not used in the atmosphere).
Also seems like the thing to do, given that we are finding more than one of these now, is to build such a thing and have it on standby and look for one that's inbound so we can launch at the best window to reach it.
Even with a NERVA engine it's a LOT of work to get to the 26 kmps of an object like ʻOumuamua so you're still at the mercy of planets being in roughly the right locations to provide some gravity assists. I think it would widen the workable solutions but something like the 10 SR assist could work with things we've actually built already.
to build a thing would be astonishingly lucky for it be parked in the right place to catch the next one, so where would you park it? seems like it would be better to build a lot of them, and park them through out in various orbits so maybe one of them has a chance to rendezvous
I was thinking park it on Earth. Have something ready to launch that consists of a very spicy nuclear upper stage to yeet a small probe at very high speed.
The whole upper stages assembly and probe could be sitting there ready to be sent up on a Falcon Heavy or Starship class booster. Might even use an expendable launch to send the upper stage into the highest energy trajectory possible.
I wonder how small you could make the probe vs how big the booster and upper stages assembly could be and how fast such a thing could be yeet. I’m thinking even a glorified cubesat size thing paired with a whole lot of rocket.
It wouldn’t slow down. It would be a flyby. But it would get us high resolution images and scans and spectroscopic readings, and if one of these visitors was artificial that would become quite obvious with a good picture.