The Mystery & Debate About the Celestial Object "Oumuamua"
Was the object named 'Oumuamua back in 2017 an artificial object, perhaps from another civilization or was it a comet? This is the debate. Below I have complied the responses by Dr. Avi Loeb and the new paper that states the object was a comet. Will we ever know?
"The first known interstellar object to visit our solar system, 1I/2017 U1 ‘Oumuamua, was discovered Oct. 19, 2017 by the University of Hawaii’s Pan-STARRS1 telescope, funded by NASA’s Near-Earth Object Observations (NEOO) Program, which finds and tracks asteroids and comets in Earth’s neighborhood. While originally classified as a comet, observations revealed no signs of cometary activity after it slingshotted past the Sun on Sept. 9, 2017 at a blistering speed of 196,000 miles per hour (87.3 kilometers per second). It was briefly classified as an asteroid until new measurements found it was accelerating slightly, a sign it behaves more like a comet.." from the article: 'Oumuamua
Oumuamua means scout in Hawaiian.
Avi Loeb: `Oumuamua is NOT an Iceberg!
Video from Dr. Brian Keating
"Recently, Bergner and Seligman explained the behavior of the first interstellar object, ‘Oumuamua, as a rare form of a quite common object, a comet. They claim it "began as an icy planetesimal that was irradiated at low temperatures by cosmic rays during its interstellar journey, and experienced warming during its passage through the Solar System. This explanation is supported by a large body of experimental work." But Avi Loeb disagrees: “In a new paper published recently in Nature -- https://www.nature.com/articles/s4158... Acceleration of 1I/‘Oumuamua from radiolytically produced H2 in H2O ice -- Jennifer Bergner and Darryl Seligman suggest that the peculiar acceleration observed by the first known interstellar object `Oumuamua, can be explained if `Oumuamua was made of water ice which was partly dissociated into hydrogen by cosmic-rays along its interstellar journey. In the abstract of the paper, the authors admit that past models involving a pure hydrogen iceberg or a pure nitrogen iceberg do not work due to theoretical or observational inconsistencies. In fact, the hydrogen iceberg model was proposed in a previous 2020 paper by Darryl Seligman himself. A few months later, I wrote a paper with Thiem Hoang, showing that heating by interstellar starlight would destroy hydrogen icebergs too quickly and not allow them to reach the solar system from their likely formation sites of giant molecular clouds." from video introduction
Acceleration of 1I/‘Oumuamua from radiolytically produced H2 in H2O ice
"In 2017, 1I/‘Oumuamua was identified as the first known interstellar object in the Solar System1. Although typical cometary activity tracers were not detected2,3,4,5,6, ‘Oumuamua showed a notable non-gravitational acceleration7. So far, there has been no explanation that can reconcile these constraints8. Owing to energetic considerations, outgassing of hyper-volatile molecules is favoured over heavier volatiles such as H2O and CO2 (ref. 9). However, there are theoretical and/or observational inconsistencies10 with existing models invoking the sublimation of pure H2 (ref. 9), N2 (ref. 11) and CO (ref. 12). Non-outgassing explanations require fine-tuned formation mechanisms and/or unrealistic progenitor production rates7,13,14,15. Here we report that the acceleration of ‘Oumuamua is due to the release of entrapped molecular hydrogen that formed through energetic processing of an H2O-rich icy body. In this model, ‘Oumuamua began as an icy planetesimal that was irradiated at low temperatures by cosmic rays during its interstellar journey, and experienced warming during its passage through the Solar System. This explanation is supported by a large body of experimental work showing that H2 is efficiently and generically produced from H2O ice processing, and that the entrapped H2 is released over a broad range of temperatures during.." from the abstract: Acceleration of 1I/‘Oumuamua from radiolytically produced H2 in H2O ice
Was ‘Oumuamua a Comet? Avi Loeb Responds to New Research
Avi Loeb’s response on ‘Oumuamua
"On March 22, 2023, EarthSky published word of a new peer-reviewed study – conducted by researchers at UC-Berkeley and Cornell – suggesting that the strange object known as ‘Oumuamua is not as strange as many had first thought. The new work suggested that ‘Oumuamua, which streaked past our sun in 2017, is simply a comet from another solar system. Meanwhile, for the past several years, Harvard astronomer Avi Loeb has been the most vocal scientist in putting forward theories that suggest ‘Oumuamua might be an alien spacecraft. Late in the day on March 23, EarthSky received an email from Avi Loeb suggesting what he called a (non-peer-reviewed) “correction” to the comet idea. Loeb wrote:
In a new paper that I submitted this morning for publication in collaboration with Thiem Hoang, we show that the paper published today in Nature by Jennifer Bergner and Darryl Seligman miscalculated the surface temperature of `Oumuamua. Bergner and Seligman suggested that the peculiar acceleration of `Oumuamua can be explained if it was made of water ice which was partly dissociated into hydrogen by cosmic-rays in interstellar space. However, their surface temperature calculation near the sun ignored the crucial cooling effect of evaporating hydrogen. By adding the cooling from hydrogen evaporation, our new paper shows that the surface temperature of the iceberg is reduced by an order of magnitude.
‘Oumuamua by the numbers
In other words, Loeb is standing by his assertion for the possibility that ‘Oumuamua isn’t a natural object. He continued, with a numerical explanation.." from the article:
Was ‘Oumuamua a comet? Avi Loeb responds to new research