UFO'S of UAP'S, ASTRONOMIE, RUIMTEVAART, ARCHEOLOGIE, OUDHEIDKUNDE, SF-SNUFJES EN ANDERE ESOTERISCHE WETENSCHAPPEN

On October 19th, 2017, the Panoramic Survey Telescope and Rapid Response System-1 (Pan-STARRS-1) in Hawaii announced the first-ever detection of an interstellar asteroid, named 1I/2017 U1 (aka. ‘Oumuamua). In the months that followed, multiple follow-up observations were conducted that allowed astronomers to get a better idea of its size and shape, while also revealing that it had the characteristics of both a comet and an asteroid.

Interestingly enough, there has also been some speculation that based on its shape, ‘Oumuamua might actually be an interstellar spacecraft (Breakthrough Listen even monitored it for signs of radio signals!). A new study by a pair of astronomers from the Harvard Smithsonian Center for Astrophysics (CfA) has taken it a step further, suggesting that ‘Oumuamua may actually be a light sail of extra-terrestrial origin.

The study – “Could Solar Radiation Pressure Explain ‘Oumuamua’s Peculiar Acceleration?”, which recently appeared online – was conducted by Shmuel Bialy and Prof. Abraham Loeb. Whereas Bialy is a postdoctoral researcher at the CfA’s Institute for Theory and Computation (ITC), Prof. Loeb is the director of the ITC, the Frank B. Baird Jr. Professor of Science at Harvard University, and the head chair of the Breakthrough Starshot Advisory Committee.

Artist’s impression of the first interstellar asteroid/comet, “Oumuamua”. This unique object was discovered on 19 October 2017 by the Pan-STARRS 1 telescope in Hawaii.

Credit: ESO/M. Kornmesser

To recap, ‘Oumuamua was first spotted by the Pan-STARRS-1 survey 40 days after it made its closest pass to the Sun (on September 9th, 2017). At this point, it was about 0.25 AU from the Sun (one-quarter the distance between Earth and the Sun), and already on its way out of the Solar System. In that time, astronomers noted that it appeared to have a high density (indicative of a rocky and metallic composition) and that it was spinning rapidly.

While it did not show any signs of outgassing as it passed close to our Sun (which would have indicated that it was a comet), a research team was able to obtain spectra that indicated that ‘Oumuamua was more icy than previously thought. Then, as it began to leave the Solar System, the Hubble Space Telescope snapped some final images of ‘Oumuamua that revealed some unexpected behavior.

After examining the images, another international research team discovered that ‘Oumuamua had increased in velocity, rather than slowing down as expected. The most likely explanation, they claimed, was that ‘Oumuamua was venting material from its surface due to solar heating (aka. outgassing). The release of this material, which is consistent with how a comet behaves, would give ‘Oumuamua the steady push it needed to achieve this boost in velocity.

To this, Bialy and Loeb offer a counter-explanation. If ‘Oumuamua were in fact a comet, why then did it not experience outgassing when it was closest to our Sun? In addition, they cite other research that showed that if outgassing were responsible for the acceleration, it would have also caused a rapid evolution in ‘Oumuamua’s spin (which was not observed).

Basically, Bialy and Loeb consider the possibility that ‘Oumuamua could in fact be a light sail, a form of spacecraft that relies on radiation pressure to generate propulsion – similar to what Breakthrough Starshot is working on. Similar to what is planned for Starshot, this light sail may been sent from another civilization to study our Solar System and look for signs of life. As Prof. Loeb explained to Universe Today via email:

“We explain the excess acceleration of `Oumuamua away from the Sun as the result of the force that the Sunlight exerts on its surface. For this force to explain measured excess acceleration, the object needs to be extremely thin, of order a fraction of a millimeter in thickness but tens of meters in size. This makes the object lightweight for its surface area and allows it to act as a light-sail. Its origin could be either natural (in the interstellar medium or proto-planetary disks) or artificial (as a probe sent for a reconnaissance mission into the inner region of the Solar System).”

Based on this, Bialy and Loeb went about calculating the likely shape, thickness, and mass-to-area ratio that such an artificial object would have. They also attempted to determine whether this object would be able to survive in interstellar space, and whether or not it would be able to withstand the tensile stresses caused by rotation and tidal forces.

What they found was that a sail that was only a fraction of a millimeter thick (0.3-0.9 mm) would be sufficient for a sheet of solid material to survive the journey through the entire galaxy – though this depends greatly on ‘Oumuamuam’s mass density (which is not well-contrained). Thick or thin, this sail would be able to withstand collisions with dust-grains and gas that permeate the interstellar medium, as well as centrifugal and tidal forces.

Artist concept of lightsail craft approaching the potentially habitable exoplanet Proxima b.

Credit: PHL @ UPR Arecibo

As for what an extra-terrestrial light sail would be doing in our Solar System, Bialy and Loeb offer some possible explanations for that. First, they suggest that the probe may actually be a defunct sail floating under the influence of gravity and stellar radiation, similar to debris from ship wrecks floating in the ocean. This would help explain why Breakthrough Listen found no evidence of radio transmissions.

Loeb further illustrated this idea in a recent article he penned forScientific American, where he suggested that ‘Oumuamua could be the first known case of an artificial relic which floated into our Solar System from interstellar space. What’s more, he notes that lightsails with similar dimensions have been designed and constructed by humans, including the Japanese-designed IKAROS project and the Starshot Initiative with which he is involved.

“This opportunity establishes a potential foundation for a new frontier of space archaeology, namely the study of relics from past civilizations in space,” Loeb wrote. “Finding evidence for space junk of artificial origin would provide an affirmative answer to the age-old question ‘Are we alone?’. This would have a dramatic impact on our culture and add a new cosmic perspective to the significance of human activity.”

On the other hand, as Loeb told Universe Today, ‘Oumuamua could be an active piece of alien technology that came to explore our Solar System, the same way we hope to explore Alpha Centauri using Starshot and similar technologies:

“The alternative is to imagine that `Oumuamua was on a reconnaissance mission. The reason I contemplate the reconnaissance possibility is that the assumption that `Oumumua followed a random orbit requires the production of ~10^{15} such objects per star in our galaxy. This abundance is up to a hundred million times more than expected from the Solar System, based on a calculation that we did back in 2009. A surprisingly high overabundance, unless `Oumuamua is a targeted probe on a reconnaissance mission and not a member of a random population of objects.”

IKAROS spaceprobe with solar sail in flight (artist’s depiction) showing a typical square sail configuration.

Credit: Wikimedia Commons/Andrzej Mirecki

According to Loeb, that there’s also the fact that ‘Oumuamua’s orbit brought it to within 0.25 AU of the Sun, which is a good orbit for intercepting Earth without experiencing too much solar irradiation. In addition, it came to within 0.15 AU of Earth, which could have been the result of orbital corrections designed to facilitate a flyby.

Alternately, he states that it is possible that hundreds of such probes could be sent so that one of them got close enough to Earth to study it. The fact that the Pan STARRS-1 survey barely detected ‘Oumuamua at its closest approach could be seen as an indication that there are many other such objects that were not detected, bolstering the case for ‘Oumuamua being one of many such probes.

Considering that astronomers recently concluded that our Solar System has likely captured thousands of interstellar objects like ‘Oumuamua, this opens the possibility for future detections which could help prove (or disprove) the case for an interstellar light sail.

Naturally, Bialy and Loeb acknowledge that are still too many unknowns to say with any certainty what ‘Oumuamua really is. And even if it does happen to be a piece of natural rock, all other asteroids and comets that have previously been detected have had mass-to-area ratios orders of magnitude larger than the current estimates for ’Oumuamua.

Oumuamua as it appeared using the William Herschel Telescope on the night of October 29th, 2017.

Credit: Queen’s University Belfast/William Herschel Telescope

That, and the fact that radiation pressure appears to be capable of accelerating it, would mean that ‘Oumuamua represents a new class of thin interstellar material that has never before been seen. If true, that opens up a whole new set of mysteries, such as how such material was produced and by what (or whom).

While it has been beyond the reach of our telescopes for almost a year now, ‘Oumuamua is sure to remain the subject of intense study for many years to come. And you can bet astronomers will be on the lookout for more of them! After all, “the Ramans do everything in threes”, right?

Further Reading: arXiv

For all of the civilizations that have shared this lump of rock we call Earth with us, it is often a sobering thought to realize that a great many of them have actually faded into the oblivion of forgotten history, forever lost to the eternal midnight of vanished knowledge that we can no longer see into. Often these civilizations were magnificent, sprawling, and advanced, yet they have nevertheless managed to melt away into the abyssal depths of time. These are the civilizations that have for whatever reasons become lost to us, invisible to our efforts to gaze upon them and learn more about them, as hard as we try. Whether it be due to a lack of written records, their sudden disappearances, or their often baffling monuments that they have left behind, these peoples have managed to defy understanding, leaving only perplexing clues in their passing. One such civilization once lived upon the Mediterranean island of Sardinia, a once proud people who have left behind mysterious structures and monuments that are as enormous as they are inscrutable.

-Going back into the mists of time, from the Bronze Age of around the 18th century BC, the island of Sardinia, in the Mediterranean Sea, was once ruled by the mysterious Nuragic civilization. This lost culture lasted until the time of the Romans, who came to the island in 238 BC, after which the enigmatic Nuragic faded into obscurity and out of existence. The Nuragic civilization left behind no written history of their people, merely romanticized and exaggerated tales told by the Greeks and Romans, and they largely remain a perplexing mystery. One of the only legacies they did leave imprinted upon the land and its history are the many megalithic stone structures they left behind, such as the nuraghe, which are ancient fort-like structures with their purposes mysterious and long lost to time, numbering in the thousands, scattered all around the Sardinian landscape. There are also the mysterious immense stone tombs that dot the landscape here, called the Tomba dei gigantic, or “The Tombs of Giants,” due to their gigantic size.

Nuragic ruins

These massive funerary monuments were constructed of enormous slabs or blocks that rose up to 13 feet high which were arranged around an even bigger central stele or portal stone with a doorway carved into it, to form corridors and rooms or chambers that can measure as much as 50 feet in length. The most famous one of these giant’s tombs is one that can be found at a place called Coddu Vecchiu, in Arzachena, northern Sardinia, and which was built between the years of 1800 to 1600 BC and first uncovered in 1966. The tomb at Coddu Vecchiu has a forecourt made of eleven granite stones standing in a semi-circle, and is composed of a central stele standing 13 feet high, which marks the entrance to the tomb, and a corridor within measuring 33 feet long.

This tomb and others like it have many legends attached to them. Since they were found to hold within them large numbers of human remains, in past ages they were said to be the leftovers from some wicked giant’s meal of human flesh, and other lore said that they served as the graves or giants or even their residences. Yet in fact they were most likely used as massive public communal graves, with the doorways serving as a passage through the barrier to the afterlife, but this doesn’t make them any less mysterious, as the rituals involved with creating them and the significance of their designs are poorly understood, and we know little about the people who made them.

One interesting idea is that the arrangement of the stones was designed to channel the telluric current and magnetic forces of the surrounding granite and energy lines, possibly for the purpose of rejuvenation and regeneration, or to provide a smoother transition to the afterlife. It is speculated that these tombs were perhaps purposefully built over earth energy lines, that the semicircular layout would focus these powers, and that not only would the dead would come here, but also the sick or wounded, hoping that these mysterious forces would heal them. This has been somewhat supported by the many visitors to such tombs who have reported feeling invigorated while there, or of feeling a thrumming energy in the air and the stone. Did this ancient people understand these forces and seek to harness them through the construction of these gigantic toms It is unclear, and for now the exact nature of the Tombs of Giants remains a mystery.

The Tomb of Giants at Coddu Vecchiu

In addition to Tombs of Giants, Sardinia has another mystery of actual giants, or at least statues of them. In 1974, some random, nondescript farmland near Monte Prama yielded quite an amazing find. There in the earth were found the broken remains of a total of over 40 massive statues, crafted into the likenesses of armored warriors, each around 2 meters in height and fashioned from solid stone, which had been abandoned there to the elements for millennia. Oddly, the statues do not appear human, but rather have outlandish and creepy visages with large concentric circles for eyes and very small, sometimes nonexistent mouths, as well as elongated necks, which along with their fierce weaponry and armor lend them a rather unsettling and formidable appearance.

The statues, which were dubbed the Kolossoi, were most certainly made by the Nuragic civilization, and were thought to have possibly been constructed as intimidating warrior guardians of the dead for a nearby necropolis, but this is uncertain, as is the reason why they look the way they do. At the time, it was quite a groundbreaking discovery, as no other such collection of larger than life sized sculptures had ever been found in Europe, and they were enigmatic in their design and purpose. Despite this, the statues were whisked away and stored in a museum vault, where they would sit in the darkness much as they had for centuries, collecting dust until decades later, when in 2006 researchers sort of rediscovered them and began piecing together some of the broken parts, a daunting task, especially since many of the fragments are missing.

One of the Sardinia giants

The reconstruction work took a total of 4 years, and 25 of the ancient warrior statues were restored to some semblance of the way they might have once looked, complete with bows, shields, swords, armor, and horned helmets. In 2014, these amazing statues were put on display at the national archaeological museum, in Cagliari, in southern Sardinia, much to the awe and amazement of visitors. The statues themselves, although finally brought into the light after so long, still keep their mysteries close. No one is really sure why they were made, how they were once arranged, or even exactly where they originally stood, and they remain another mystery of Sardinia’s lost Nuragic people.

These mysteries have managed to remain elusive and murky, the remnants of a culture who left little in the way of information about themselves except these massive stone structures and statues, practically the only evidence that they ever even existed at all. Yet even though we have these relics of the past to use in order to try and peer through the window of history, that window remains rather foggy, what lies beyond indistinct and fleeting. The Tombs of Giants, giant warrior statues, and other such structures scattered about Sardinia have managed to remain as cryptic puzzles that fire the imagination and offer hints, but no real answers, the people who made them just as mysterious as they ever were, their culture and ways lost to time even as their grand, giant constructions live on.