Oumuamua might be artificial lightsail

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A new analysis of the velocity and path of the interstellar object Oumuamua suggests it might be an artificial lightsail.

The study, which was posted online earlier this month, suggests that Oumuamua’s strange “excess acceleration” could be artificial in nature, as it has been implied that it is not an active comet. “Considering an artificial origin, one possibility is that ‘Oumuamua is a lightsail, floating in interstellar space as a debris from an advanced technological equipment,” researchers wrote in the paper.

The paper continues: “Lightsails with similar dimensions have been designed and constructed by our own civilization, including the IKAROS project and the Starshot Initiative. The lightsail technology might be abundantly used for transportation of cargos between planets or between stars.”

They even theorized that Oumuamua “may be a fully operational probe sent intentionally to Earth vicinity by an alien civilization,” though that scenario was called “exotic.”

All of this is speculation. However, that the object is moving faster than expected, based on the initial data of its path, is quite intriguing. The authors of the paper concluded that the excess speed was caused by “solar radiation pressure.” They also calculated that for the light pressure to cause that increase in speed as it moves away requires it to have a large surface area.

The observations are not sufficiently sensitive to provide a resolved image of ‘Oumuamua, and one can only speculate on its possible geometry and nature. Although periodic variations in the apparent magnitude are observed, there are still too many degrees of freedom (e.g., observing angle, non-uniform reflectively, etc.) to definitely constrain the geometry. The geometry should not necessarily be that of a planar sheet, but may acquire other shapes, e.g., involving a curved sheet, a hollow cone or ellipsoidal, etc. Depending on the geometry our estimated value for the mass-to-area ratio will change, but the correction is typically of order unity.

They then speculate the possibility of the object being an interstellar probe.



  • hondo

    A rock or hunk of ice – slingshot out from God know where and when. I suspect interstellar space is not a complete void, but filled with lots of stuff like this.
    We just never noticed one before.

    Pity – I would have loved it to be Rama.

  • The aliens are not among us. The truth is out there—and it is that we are not being visited by extraterrestrials. A flying saucer didn’t crash at Roswell, we aren’t reverse engineering alien technology at Area 51, and otherworldly tourists, anatomists or anthropologists are abducting no one from their homes.

    I’ve said it and I’ve said it with certainty. Could I be wrong? Yes, and I will be the first to admit my mistake when someone brings forth credible evidence that our planet is being visited by creatures from another world. But until then, I will be a skeptic on this issue.

    Carl Sagan said, “Extraordinary claims require extraordinary evidence.” Now, I may not be in the same league as Carl Sagan, but in this case I agree with him completely. Stories of strange lights in the sky, sightings of aircraft performing seemingly impossible acrobatic maneuvers before “shooting straight up,” presumably into space, or recollections of missing time after observing one of these weird aerial phenomena do not qualify as extraordinary evidence.

    But what about the pictures? Since there have been cameras, there have been fuzzy pictures of these strange objects in the night sky. Most are obviously fake, some are clearly explainable, and, yes, some are truly puzzling—but a puzzling object seen from an aircraft window does not an alien spaceship make! Much simpler explanations (than alien visitors) are almost certainly waiting in the wings to be proffered.

    I don’t want to get into a debate with true believers out there who have seen something they cannot explain, or have read about an encounter that had to be with a creature from another world. Sending me pictures taken with your cell phone camera will not convince me. No, the evidence would have to be something akin to Gort standing on the National Mall for me to be convinced aliens are visiting us.

    Why am I so adamant? Why would I take a position that will almost certainly cause many readers to call me “closed minded” and a veritable Luddite? Because the thought of us being visited by aliens from another planet at this time simply is so highly improbable as to be, for all practical purposes, impossible.

    Let me be clear. I do believe that there may be other life in the universe. I find the thought of humanity being alone in the universe to be not only depressing, but also arrogant. Surely, if it can happen here, with us, then it can happen elsewhere also. But, almost as certainly, life is rare. Intelligent tool-using life is likely even more rare. It is incredibly unlikely that intelligent, tool using life just happens to come visit us during a brief moment in the history of our species when are beginning to explore space ourselves.

    I’d better explain how I come to this conclusion.

  • Cotour

    “May be”

    “Could be”

    Is this a Richard Hoagland story?

    Could it be a giant alien flying space baked potato? Could be.

    There is much more actual evidence that this https://youtu.be/34Kjt9Os8uY is in deed so rather than this story about this asteroid being something other than it is. And I am certainly open to the concept that there are aliens somewhere, but “could be” and “may be” do not make it for me when there are plenty of other observations right here on the planet that indicate something other than what we know or recognize as being so.

  • Ryan Lawson

    Given this latest bit of data and after reading their full report myself, I suspect more that this might be an advanced form of external fuel tank jettisoned long ago. They describe one explanation being a hollow object with a shell thickness of only a few millimeters. One of the goals with fuel tanks is to minimize the mass of the tank itself as best as possible. Make an ultrathin cylinder with a 10 L to 1 W ratio, stick a variation of a Whipple shield on the front cross-section and you have an external fuel tank. Too me, I have a hard time thinking any sufficiently advanced civilization would spend much time using light sails, particularly for interstellar travel. Ships travelling between stars, if they plan to maneuver, would need large numbers of fuel tanks. In a span of time, large ships moving around for hundreds of years or thousands of years would litter space with jettisoned tanks. If their data is correct, a natural explanation for this object’s behavior seriously looks far less probable than an artificial one.

    To Mr. Jerry, these UFOs are not a recent phenomena. They have been interpreted differently depending on the era and culture. How do you imagine a Roman general would interpret seeing lights moving around in the sky? I am of the notion that once a civilization expands successfully into a few star systems they will eventually fill an entire galaxy unless someone else stops them. There is a huge technological and biological hump to overcome, but once you are past it you go everywhere like spores born up by a strong gust. Somewhere in our galaxy, given the span of time behind us, that must have already happened. Earth would be nothing new to them, just one of millions of worlds covered in primitive life. They probably just come here for a vacation to drown out the boredom of their technological immortality.

  • wayne

    These people, have PhD’s?
    I suggest, they get real jobs.

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