But the press is giving it their best shot.
Avi Loeb, is one of the world's leading astrophysicists, but recently (with the help of the press) he's been feeding his reputation into the wood chipper.
In December 2017, Loeb cited ʻOumuamua's unusually elongated shape as one of the reasons why the Green Bank Telescope in West Virginia should listen for radio emissions from it to see if there were any unexpected signs that it might be of artificial origin,[40] although earlier limited observations by other radio telescopes such as the SETI Institute's Allen Telescope Array had produced no such results.[41] On December 13, 2017, the Green Bank Telescope observed the asteroid for six hours. No radio signals from ʻOumuamua have been detected.[42][43]
On October 26, 2018, Loeb and his postdoctoral student Shmuel Bialy submitted a paper exploring the possibility of the interstellar object ʻOumuamua being an artificial thin solar sail accelerated by solar radiation pressure in an effort to help explain the object's non-gravitational acceleration.[44][45][46] Other scientists have stated that the available evidence is insufficient to consider such a premise,[47][48][49] and that a tumbling solar sail would not be able to accelerate.[50][51] In response, Loeb wrote an article detailing six anomalous properties of ʻOumuamua that make it unusual, unlike any comets or asteroids seen before.[52][53]
On November 27, 2018, Loeb and Amir Siraj, an undergraduate student at Harvard College, proposed a search for ʻOumuamua-like objects which might be trapped in the Solar System as a result of losing orbital energy through a close encounter with Jupiter.[54] They identified four candidates (2011 SP25, 2017 RR2, 2017 SV13, and 2018 TL6) for trapped interstellar objects which could be visited by dedicated missions. The authors pointed out that future sky surveys, such as with Large Synoptic Survey Telescope, could find many more.[55]
In public interviews and private communications with reporters and academic colleagues, Loeb has become more vocal regarding the prospects of proving the existence of alien life.[56] On April 16, 2019, Loeb and Siraj reported the discovery of the first meteor of interstellar origin.[12] Extraterrestrial: The First Sign of Intelligent Life Beyond Earth, a popular science account concerning ʻOumuamua, written by Loeb,[57] was published in 2021.
As with Oumuamua, Loeb's latest argument for evidence of alien technology comes in three parts:
1. Data indicate that the object is interstellar;
2. The object appears to have some anomalous properties;
3. I reallyreallyreally want to believe this.
"It has material strength that is tougher than all space rock that were seen before, and catalogued by NASA," added Loeb, "We calculated its speed outside the solar system. It was 60 km per second, faster than 95% of all stars in the vicinity of the sun. The fact that it was made of materials tougher than even iron meteorites, and moving faster than 95% of all stars in the vicinity of the sun, suggested potentially it could be a spacecraft from another civilization or some technological gadget."
It seems like most of the heavy lifting on this project was done by the grad student Amir Siraj, whose account in Scientific American is considerably more sober. Perhaps, still being in his twenties, Siraj would like to keep his reputation in one piece for a few more decades.
The story began in April 2019, when I found what’s thought to be the first known interstellar meteor, hiding in plain sight in publicly accessible data sourced from the U.S. government. Called IM1, this object had burned up in the atmosphere and rained fragments down into the ocean off the coast of Manus Island, Papua New Guinea, five years prior, registering as an anomalously speedy and bright fireball in the sensors of secret spy satellites operated by the U.S. Department of Defense. Working with my then-adviser, the Harvard astrophysicist Avi Loeb, I analyzed the U.S. government data to show how the trajectory and other properties of IM’s fireball were consistent with the meteor having an interstellar origin.
...
In the months leading up to the expedition, which would take place aboard a ship called the Silver Star, I focused on the scientific planning while Avi concentrated on funding and logistics. Using archival seismic data from terrestrial instruments that had picked up the sonic boom from IM1’s fireball, I was able to pin down the resulting debris field to some 50 miles offshore of Manus Island, in an arc of open water seven times smaller than the area provided to us by the Department of Defense. This localization would allow for a chance, albeit slim, of success in realizing my dream of holding a piece of history—a bona fide interstellar object—for the very first time.
...
These spherules are tantalizing, especially given that many of them show compositional anomalies relative to typical ones. Could some of them represent the first material ever recovered from an interstellar object? Or do they belong to the background population of spherules from “local” solar system meteors, which have accumulated on the seafloor over geological time? Or were they produced by humans, through high-temperature processes like welding?
A definitive answer will emerge from studying the isotopic signatures embedded within the spherules. Compared to spherules from run-of-the-mill meteorites, an overabundance of rare isotopes (or an underabundance of common isotopes) in the ones collected from our search region would be compelling evidence for IM1’s interstellar origin. This isotopic analysis is currently underway at the University of California, Berkeley, and will soon begin at Harvard University.
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