Oumuamua – object of speculation

Nearly five and a half years ago, astronomers at the Haleakalâ Observatory in Hawaii discovered something none of them expected. It was a cigar-shaped object making a hyperbolic pass at the Sun – so they concluded it was an interstellar object. They named this object Oumuamua, which means scout – or “first messenger from afar” – in Hawaiian. But this object did not dive in and coast out – apparently it accelerated on the outward leg of the hyperbola. This has led one professional astronomer and one amateur space enthusiast to insist that someone built this object. Feverish speculation along this line dominated science news – until last week. Two scientists from “Cal Berkeley” and Cornell now think they know why this object accelerated on its way out. But their theory might not settle the debate – and in CNAV’s opinion, both these theories are wrong.

What is Oumuamua?

Why are the nations in an uproar, / And the peoples devising a vain thing? Psalm 2:1, NASB (1995)

Wikipedia has the current data on Oumuamua, and the facts of its discovery. Breathless astronomers call it an interstellar object, the first of its kind anyone has ever seen. More sober-minded astronomers call it a hyperbolic asteroid, by reason of its path. It is more likely a long-period comet.

At its closest approach to the Sun, Oumuamua came within a quarter of the distance from Earth to the Sun. As such it came inside even the orbit of Mercury. On its way out, it approached even more closely to Mercury, Venus – and the Earth. In fact the Hawaiian astronomers saw it so easily because it was closely approaching Earth, on its way out. The eccentricity of its path is 1.2, consistent with a hyperbola. Therefore the object is flying faster than escape speed from the Sun.

“Oumuamua trajectory animation3” by Tom Ruen is licensed under CC BY-SA 4.0 .

The best estimates of its size are 250 yards long and 38 yards around, give or take a yard. This object also tumbles, so it has no principal axis of spin. Different astronomers have reported its “day” at seven and eight hours, give or take five or six minutes.

The most remarkable thing about the path of this object is that it deviated from a strict hyperbolic path before dwindling from sight. Therefore trajectory is not the word for its path; course might be.

Theory one: a derelict light sail

Professor Avi Loeb of Harvard University has insisted, virtually since the Hawaii astronomers first saw it, that someone built Oumuamua. According to Scientific American, Loeb had planned building light sailboats laden with sensory equipment, and using lasers to push them to nearby stars. When he first heard of Oumuamua, he seems to have decided right away that this was a light sailboat. Its proportions do not match those of any known Maverick of the Solar System. It is also ten times brighter than most such objects. Conclusion: it is the first evidence of intelligent life beyond the solar system. He said so, in a paper he published in late 2018.

Perhaps the only reason he could get away with publishing such a theory without seeing all his grant monies dry up is that he has tenure. He has a Frank B. Baird Jr. Professorship of Science at Harvard – apparently no small matter. But he has so far failed to convince anyone of his theory – except for Jordan “The Angry Astronaut” Wright.

In fact his scientific colleagues treat him with scorn – and he seems to have returned the favor. But mostly he says what many before him have said: that he has a competent mathematical basis for assuming that extraterrestrial civilizations have in fact arisen. And that one such civilization built his object – which he assumes for the moment is a derelict. That in turn means that its builders are long dead, and this object could be their last monument.

Theory two: comet-like outgassing

On Wednesday March 22, Jennifer Bergner and Darryl Seligman published their competing theory in the journal Nature. They conclude that Oumuamua is a comet – specifically a water-ice comet that underwent thermolysis to form molecular hydrogen and oxygen. As it passed incredibly close to the Sun, it released its hydrogen load. That release propelled it on its outbound leg, when the Hawaii astronomers first saw it. And why can’t we see the “tail” of this comet? Because hydrogen would have been effectively invisible – literally too thin to see.

Several lay news organs picked up on the Nature article right away. But Avi Loeb poured contempt on it. Thus far his response has appeared only at Medium.com, in a blog entry. (Jordan Wright quoted from Loeb’s rebuttal at some length yesterday.)

Loeb lists several problems with the Bergner-Seligman theory. First he accuses them of “mixing two failing models,” i.e. a pure hydrogen iceberg and a pure water iceberg. Next he suggests that the hydrogen, once produced by thermolysis or “radiolysis,” would escape long before the object arrived. Furthermore, the outgassing should have changed the object’s tumbling characteristics – and this did not happen.

The biggest problem is the missing tail. Another alleged interstellar comet, called Borisov, has a tail. Where, he asks, is Oumuamua’s tail? (In fact, the same observatory, in 2020, saw an apparent tailless comet. It turned out to be the booster from the failed Surveyor 2 mission in 1966.)

What else could Oumuamua be?

Loeb returned to his original theory: that someone built Oumuamua. He insists that it does not have a cigar shape at all, but a disk shape. The object is ten times brighter at one “time” of its “day” than another, leading him to favor the disk shape. He currently believes this object is either a light sail (without its attached craft), or a broken piece of a wrecked Dyson Sphere. (Freeman Dyson proposed enclosing the Sun in a shell, one astronomical unit in diameter, and living on the inner surface.)

The fundamental question that I am curious about, is whether `Oumuamua was natural or artificial in origin. If the next `Oumuamua appears artificial, then we might feel like home owners who identified all objects in their back yard as rocks, including those tennis balls which originated from the cosmic street and were thrown by our neighbors.

Except that by his own reckoning, the “neighbors” are long dead. So this object, if someone did build it, is more like a shingle blown off an abandoned house. That, of course, is the main problem with Avi Loeb’s theory – it requires another one. Where did the builders come from – and where did they go? What could have destroyed a Kardashev Type Two civilization, the only type capable of building a Dyson Sphere? Did the civilization simply degenerate into anarchy? Or did another civilization annihilate it in a war?

The third alternative for Oumuamua

CNAV offers a third alternative, having its basis in the Hydroplate Theory of the Global Flood by Walter T. Brown. Oumuamua, and Borisov, are Long Period Comets. Like all other comets, they formed from ejected water, rock and mud from the Global Flood. They simply flew father away from the Sun than any of their fellows – far enough, in fact, to be subject to the full gravitational influence of the Sun and every other object in orbit around it. As they re-entered the inner solar system, they fell outside the influence of every object whose orbit they crossed. For Oumuamua that definitely included all the gas giants, and indeed every object except the Sun.

So of course Oumuamua was following a hyperbolic path when the Hawaiian astronomers first saw it. It would also have the momentum it had accumulated along the way. By now it is once again subject to more gravitational pull from other objects beyond the Earth.

Deal-killers

Long Period Comets are, as Brown acknowledges, the greatest weakness of his theory of their origin. But every other theory of cometary origin has deal-killers that remove it from serious consideration. Or they would – except that the same “tyrannical majority” mind-set that leads other scientists (ironically) to reject the extraterrestrial wreckage theory of Oumuamua, also leads them to reject the Global Flood., With the result that Brown alone is talking about the deal-killers. The worst of these is the finding of ice on the Moon and Mercury, which no other comet-origin theory can explain. Jan Oort’s Cloud of Comets theory accounts for the two weakest of the seven theories of comet origins. An Interstellar Capture Theory to explain all comets actually exists – and is almost as weak.

But Brown has not yet revised his book to account for Oumuamua or Borisov. These two are the first two hyperbolic “Mavericks” that anyone has ever seen. Still, the only real weakness in that regard is the failure (thus far) to detect enough massive objects to account for gravitational attraction to change their orbits in the far reaches of the solar system. But even NASA itself admits that another planet-sized object might exist in those far reaches. They call it Planet X or Planet 9, and believe it weighs 10 Earth masses and might orbit as far away as six hundred astronomical units from the Sun.

Conclusion

If the solar system has an object that heavy, then God must have created it to begin with, for that mass did not come from Earth. But some extra mass exists, for which we have not accounted. That mass could be all we need to explain Oumuamua, Borisov, and every Long Period Comet we know.

Interestingly, even Avi Loeb seems to have abandoned any idea, if he entertained it at all, that Oumuamua is what the Hawaiian astronomers called it: a scout. No scoutcraft would tumble – not if it’s functioning. If that’s a vessel, then its crew must be getting space-sick from their tumbling act. The light sail, if that’s what it is, could not provide consistent acceleration in a tumbling attitude. And no scout could conduct adequate reconnaissance without a stable platform for its cameras and antennae.

So perhaps to save his theory from utter absurdity, Loeb regards Oumuamua as a wreck, or a piece of wreckage. In short, a “ruin a thousand times older than Troy,” to paraphrase Arthur C. Clarke. Still, Occam’s Razor defeats his theory, because it requires another one. The Bergner-Seligman theory suffers from a slightly different weakness – the non-viability of most comet origin theories. We can indeed regard Oumuamua and Borisov as “natural” or “wild-type” objects, relics of the most violent event the Earth has ever known.

Update

Mr. Wright apparently had a copyright dispute, of dubious validity, with the Arts and Entertainment Network over an animation he used. Unfortunately for him, YouTube refuses to countenance any appeal. He therefore released another version to make sure at least some of his message got out. CNAV has elected to embed it here.