A newly published study will surely excite conspiracy theorists: it acknowledges that the interstellar object ‘Oumuamua could potentially be an alien probe or equipment of some kind. The uniquely shaped space rock was spied back in October 2017, opening the door to a mystery that still hasn’t been solved. Though many questions about the object remain, one thing is clear: ‘Oumuamua originates from beyond our solar system.
The study comes out of the Harvard Smithsonian Center for Astrophysics and details some of the space object’s unusual characteristics, including its “extreme aspect ratio” and spinning motion. As previously published, scientists have determined that ‘Oumuamua, despite its observed properties, is not an active comet. It doesn’t present a cometary tail, gas emission or absorption lines, or any cometary activity.
The new study is quite technical, looking at aspects including the object’s unusual, incredibly thin size. The paper states, in part:
We have shown that the observed non-gravitational acceleration of ‘Oumuamua, may be explained by Solar radiation pressure. This requires a small mass-to-area ratio for ‘Oumuamua of (m/A) ≈ 0.1 g cm−3. For a planar geometry and typical mass densities of 1–3 g cm−3 this gives an effective width of only 0.9–0.3 mm, respectively. For a material with lower mass density, the inferred effective width is proportionally larger. We find that although very thin, such an object can travel over galactic distances, maintaining its momentum and withstanding collisional destruction by dust grains and gas, as well as centrifugal and tidal forces.
This raises a big question, though: what produced something with such a unique mass-to-area ratio? The study points out that known space objects from our solar system, such as comets and asteroids, have much larger mass-to-area ratios than this interstellar object. Was ‘Oumuamua produced naturally or is it “of an artificial origin?”
The paper takes time to consider the latter possibility, saying that the interstellar object could be “a lightsail, floating in interstellar space as a debris from an advanced technological equipment … The lightsail technology might be abundantly used for transportation of cargos between planets or between stars.”
A couple suggestions for an artificial origin are put forth, including the possibility that ‘Oumuamua is non-operational artificial space debris; the second is a suggestion that it could be a probe sent toward Earth from an intelligent non-human source. The researchers call the latter a “more exotic scenario,” concluding, “A survey for lightsails as technosiganures in the Solar System is warranted, irrespective of whether ‘Oumuamua is one of them.”
The full study can be read here.