OUMUAMUA INTERSTELLAR PROBE II
https://www.theflatearthsociety.org/forum/index.php?topic=30499.msg2122759#msg2122759 (part I)
"Astronomers and cosmologists have no issues with the ideas of dark matter and dark energy controlling the Universe, even though they still do not know what these things are made of or how they operate. But aliens – oh no, not that uncontrollable possibility."
Dr. Abraham Loeb
Harvard University
It turns out that the shape of Oumuamua must be discoidal.
https://arxiv.org/pdf/1906.03696.pdf"Here's the problem with 'Oumuamua: It moved like a comet, but didn't have the classic coma, or tail, of a comet, said astrophysicist Darryl Seligman, an author of the solid hydrogen hypothesis, who is starting a postdoctoral fellowship in astrophysics at the University of Chicago.
'Oumuamua was the first object ever seen flying into our solar system and back out again. That's opposed to most solar system objects that turn circles around the sun, never leaving the celestial neighborhood. Its journey and the fact that it was accelerating suggested 'Oumuamua, which is estimated to be about 1,300 to 2,600 feet (400 to 800 meters) long, was a comet. And yet, "there was no 'coma' or outgassing detected coming from the object," Seligman said. Normally, comets come from regions more distant from the sun than asteroids, and ice on their surface turns straight into gas as they approach the sun, leaving behind a trail of gas, or what we see as a beautiful comet tail, Seligman said.
That outgassing changes how the comet moves through space, he said. It's a bit like a very slow rocket engine: The sun strikes the comet, the warmest part of the comet bursts with gas, and that gas flowing away from the comet sends it tumbling faster and faster away from the sun.
In a paper published June 9 in The Astrophysical Journal Letters, Seligman and Yale astrophysicist Gregory Laughlin proposed that the object was a comet made up partly or entirely of molecular hydrogen — lightweight molecules composed of two hydrogen atoms (H2).
H2 gas freezes into a puffy, low-density solid only when it's very cold — minus 434.45 degrees Fahrenheit (minus 259.14 degrees Celsius, or just 14.01 degrees above absolute zero) in Earth's atmosphere. Researchers had already proposed the existence of "hydrogen icebergs" out in the very cold reaches of space, Laughlin and Seligman wrote in the study. And outgassing hydrogen wouldn't be visible from Earth — meaning it wouldn't leave behind a visible comet tail.
The numbers worked out neatly; while a few other substances (like solid neon) could potentially explain the coma-free acceleration, hydrogen was the best match for the data.
Now, in a new paper published Monday (Aug. 17) in The Astrophysical Journal Letters, Loeb and Thiem Hoang, an astrophysicist at the Korea Astronomy and Space Science Institute, argue that the hydrogen hypothesis couldn't work in the real world — which would mean that there is still hope that our neck of space was once visited by advanced aliens — and that we actually spotted their presence at the time.
But in their new paper, Hoang and Loeb respond to this idea and argue that the hydrogen iceberg explanation has a basic problem: Comets form when icy grains of dust bump into each other in space and form clumps, and then those clumps attract more dust and other clumps. And comets are like snowmen: they survive only as long as they don't melt.
The stickiness that helps form comets is similar to the stickiness of ice cubes coming straight out of a cold freezer. Leave an ice cube on the counter for a minute or two, let its surface warm up a bit, and it won't feel sticky anymore. A thin film of liquid water on its surface makes it slippery.
Hoang and Loeb argued that even starlight in the coldest parts of space would warm up small chunks of solid hydrogen before they could clump together and form a comet of 'Oumuamua's large scale. And more importantly, the trek from the nearest "giant molecular cloud" — a dusty, gassy region of space where hydrogen icebergs are thought to form — is far too long. A hydrogen iceberg travelling hundreds of millions of years through interstellar space would have fallen apart, cooked by starlight.
Seligman said that Loeb's analysis was correct that no hydrogen comet would survive such a long trip."Hydrogen icebergs don't live that long in the galaxy.," he said. "And you definitely don't have time to get all the way from [the nearest] giant molecular cloud."
The theory only works if 'Oumuamua is just 40 million years old, he said. Over that time frame, outgassing could have molded the comet's oblong shape without destroying it entirely."
""Shortening the distance that that H2 iceberg needs to travel does not solve the problems we outline in our paper, because the H2 iceberg would have formed when its parent planetary system formed, billions of years ago,” and in those eons, the iceberg would have evaporated, he told Live Science in an email.
Loeb also said that hydrogen icebergs are expected to come from giant molecular clouds, not parts of space like Carina or Columba. And he reiterated that no hydrogen iceberg could survive the trek from the nearest giant molecular cloud.
Asked if there is a clear leading candidate explanation for 'Oumuamua's acceleration, Loeb referred Live Science to a not-yet-released book he authored called "Extraterrestrial: The First Sign of Intelligent Life Beyond Earth," due for publication in January."
https://iopscience.iop.org/article/10.3847/2041-8213/abab0c/pdf"Using observations from NASA’s Hubble Space Telescope and ground-based observatories, an international team of scientists have confirmed Oumuamua, the first known interstellar object to travel through our solar system, got an unexpected boost in speed and shift in trajectory as it passed through the inner solar system last year.
“Our high-precision measurements of ′Oumuamua’s position revealed that there was something affecting its motion other than the gravitational forces of the Sun and planets," said Marco Micheli of ESA’s (European Space Agency) Space Situational Awareness Near-Earth Object Coordination Centre in Frascati, Italy, and lead author of a paper describing the team's findings."
However, the space object Oumuamua cannot be a comet (see part I).
And F. Whipple's outgassing theory (jets of gaseous material expelled from its surface), put forth for comet Encke, was published in order for mainstream astrophysics to save face: Encke had found that the comet’s orbital period was decreasing by about 2.5 hours every revolution and had showed that this behaviour could not be explained by gravitational perturbations (slight changes in an orbit) caused by the planets.
F. Whipple chose to disregard the clear data which proved that Encke is an electric comet.
Professor W. Stanley Jevons wrote in Nature, December 28, 1871:
“The observed regular diminution of period of Encke’s comet is still, I believe, an unexplained phenomenon for which it is necessary to invent a special hypothesis, a Deus ex machina, in the shape of an imaginary resisting medium... It is asserted by Mr. R. A. Proctor, Prof. Osborne Reynolds, and possibly others, that comets owe many of their peculiar phenomena to electric action... I merely point out that if the approach of a comet to the sun causes the development of electricity arising from the comet’s motion, a certain resistance is at once accounted for.”
Cometary charging
“It is possible, however, that there are also other, just as natural, ways of looking at the matter. It might be imagined that after great heating by direct insolation, the comet is charged negatively by cathode-rays from the sun, and that the charging reaches so high a potential that the comet discharges itself electrically, so to speak in the direction of its own shadow. These discharges may also be imagined to be due to some extent to an emission of secondary rays from the cosmic dust of the comet. I have been led to this thought by experimental analogies which will be described farther on. Answering to the idea that a comet is an accumulation of carbonaceous cosmic dust almost without atmosphere, I have carried out experiments in which the cathode in a vacuum-tube consisted of a carbonaceous material. The most recent investigations of the comet-spectrum seem to indicate that the radiation from a cornet may be compared to that from a cathode in a Crookes ‘ tube (DESLANDRES, FOWLER).”
[..]
“It would be natural, therefore, to compare the above-mentioned layers that were favorable to the development of comet ‘s tails with the pencils of the strongest and magnetically stiffest corpuscle-rays which we imagine to emanate from the region surrounding the sun-spots, and which, when they sweep past our earth, produce powerful magnetic disturbances. It may be that it is these very rays, with their abundance of energy, that can charge the comet mass to a high negative tension, and thus occasion the secondary electric discharge from the comet into space.
“One circumstance that speaks strongly in favour of a hypothesis such as this, is the greater development thought to have been found in years of sun-spot maxima than in years of sun-spot minima. This has been demonstrated, for instance, in Encke ‘s comet, by BERBERICH and BOSLER, the latter having given an exceedingly interesting graphic representation of this condition, which is reproduced here. The agreement, as will be seen, is so striking that it seems to leave little room for doubt that we here have phenomena that must be intimately connected with one another.”
Birkeland’s Fig. 230. Top curve, dotted: Comet brightness Bottom curve, solid: Number of sunspots. Original chart by M. J. Bosler (1909)
M. J. Bosler, “Sur les variations d’éclat de la comète d’Encke et la période des taches solaires” FULL TEXT (1909) Comptes rendus hebdomadaires des séances de l’Académie des sciences, 1909 (T. 148). Chart: page 1740
https://gallica.bnf.fr/ark:/12148/bpt6k3102f/f1740.table