Abraham Loeb and Shmuel Bialy, the new go-to guys for all things ‘Oumuamua – the cigar-shaped, interstellar comet/asteroid/spacecraft/noneoftheabove which zipped past us last year and that this pair thinks is some sort of extraterrestrial solar sail, have issued a new report warning that they will be issuing a lot of new reports because ‘Oumuamua is far from the only interstellar object traveling in, around or through our solar system. Not only that, the life forms – if there are any – on the objects may be frustrated and upset because their vehicle/sail/rock/paper/scissors is stuck in the solar system. Do we really need anything more to worry about?
“We find that there should be hundreds of `Oumuamua-size interstellar objects identifiable by Centaur-like orbits in polar or retrograde motion.”
These two Harvard (Loeb is a professor and Bialy a graduate student) astronomers don’t waste any time getting to the point in the opening of their new paper, “Identifying Interstellar Objects Trapped in the Solar System through Their Orbital Parameters,” which is being reviewed for publication by the Monthly Notices of the Royal Astronomical Society. Centaurs are minor space objects orbiting the sun between Jupiter and Neptune who earn their Greek mythological half-human/half-horse name by sharing characteristics with asteroids, comets, small planets, planet fragments and now, according to Loeb and Bialy, unidentifiable stuff that may be from another star system.
Centaur
One odd characteristic of Centaurs is their retrograde orbit of the sun, putting them in opposite rotation with all planets and most other space objects. Astronomers have recently concluded that one such Centaur — 2015 BZ509 — has been in retrograde orbit since the formation of the Solar System some 4.5 billion years ago, which makes it highly likely to have been captured from another solar system. For their study, Loeb and Bialy simulated these objects, then compared the models with data from the Panoramic Survey Telescope and Rapid Response System (Pan STARRS) survey which watches moving or variable sky objects.
“This yields roughly one such object (of a hundred meter size) per the volume defined by the Earth’s motion around the Sun. In total, each planetary system needs to eject about 10^{15} such objects during its lifetime… Out of those a small fraction is trapped by the Solar System, as objects pass close to Jupiter and lose energy through their gravitational interaction with it. The Sun-Jupiter system acts as a fishing net that hosts a few thousand captured objects at any time. The objects eventually get kicked out of the system, but new ones get captured, and so there is a steady population.”
The model predicted thousands of ‘Oumuamua-like objects with hundreds easily identifiable by their orbits. In fact, Siraj and Loeb identified four possible ‘Oumuamuas that have already been found — 2011 SP25, 2017 RR2, 2017 SV13, and 2018 TL6. Loeb thinks these are perfect candidates for a space mission.
Centaurs?
“Since these objects are trapped, we can fly by them, take a photograph or land on their surface. This will allow us to learn about their structure, composition and origins. It will also allow us to infer better the conditions at their nurseries outside the Solar System. And finally, it may allow us to identify objects of artificial origin, like finding plastic bottles on an otherwise pristine beach.”
Artificial origin! There he goes again. Could one of these be the wreck of an alien probe, as Loeb stated in a previous paper about ‘Oumuamua?
“This will be revolutionary, as it will demonstrate that we are not alone and will shed light on advanced technologies beyond our own. It holds the potential for being the most important result in science and technology for centuries to come.”
You know, he’s starting to make some sense.
Paul Seaburn (CLICK HERE TO READ AND SEE MORE)
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