Exploring the Possibility of a Hidden Ice Giant in the Oort Cloud

Monday - July 3 2023, 06:55 UTC - 1 year ago

Scientists have calculated a 7% probability of a neighboring planet within our solar system in the distant Oort cloud. Drawing from Percival Lowell's 1906 pursuit of a 'Planet X' beyond Neptune's domain, simulations of the unstable celestial mechanics of the early solar system propose a potential icy giant planet, much farther away than Lowell's proposed Planet Nine. Such a planet is likely to be faint with an elongated orbit similar to a comet's ellipse. It is hypothesized that multiple celestial bodies could be present in the Oort cloud, emphasizing the vast untapped potential for discovery within our own solar system.

Scientists have just calculated that there's a seven percent chance of another neighboring planet within our solar system, according to a new study published to the preprint server arXiv (yet to be peer-reviewed). Although the odds may appear slim, let's focus on the fact that they're not zero either.

This enigmatic world, the researchers speculate, would likely reside in the distant Oort cloud— a spherical region teeming with icy fragments and comets, spanning billions to trillions of miles from the sun.

Where could the ice giant planet be hiding? .

Pluto's controversial reclassification as a dwarf planet, reducing our solar system's planet count from nine to eight, hasn't deterred astronomers from their quest for discovery. Drawing inspiration from Percival Lowell's relentless pursuit in 1906, a segment of the scientific community remains committed to the existence of a colossal planet, nicknamed "Planet X," lurking beyond Neptune's domain.

Now, in this latest study, an international team simulated the unstable celestial mechanics of the early solar system, proposing there could be an icy giant situated much farther away than Lowell could have predicted.

"It's completely plausible for our solar system to have captured such an Oort cloud planet," co-author Nathan Kaib, told Popular Science.

"These hidden strangers are "a class of planets that should definitely exist but have received relatively little attention," emphasized Kaib, who is an astronomer at the Planetary Science Institute.

According to the study, giant planets like Jupiter, Saturn, Uranus, and Neptune form twin siblings. However, their powerful gravity leads to turbulent interactions, destabilizing the young solar system.

Occasionally, a planet gets ejected from the system or pushed to the outer regions, resulting in peculiar orbital characteristics that trace its journey.

"The survivor planets have eccentric orbits, which are like the scars from their violent pasts," said lead author Sean Raymond, a researcher at the University of Bordeaux's Astrophysics Laboratory.

Raymond explained that an exiled Oort cloud planet would be distant from its star and have an elongated orbit resembling a comet's ellipse, unlike Earth's nearly circular path. Due to the vast distance, detecting such a planet is highly challenging, as it would be faint.

Could the ice giant be Planet X? .

Intriguingly, Raymond and his team explained that the Oort cloud planet could not be the 'Planet X' pursued by Lowell.

"The Oort cloud planets in our simulations would be much more distant than the proposed Planet Nine orbit—at least 10 times further away," highlighted Kaib. "Our simulations cannot place planets on Planet-Nine-like orbits." .

Did you notice Kaib's use of the term' planets,' implying the presence of multiple hidden celestial bodies? At the least, these findings emphasize the vast untapped potential for discovery within our own solar system.

The complete study was published in Arxiv and can be found here.

Study abstract:Dynamical instabiity during the formation of the giant planets is a potential mechanism to explain the presence of an accumulating number of low-mass orbital bodies in the distant Oort cloud. Here we simulate the solar system’s evolution during the epoch of giant planet instability. We find a significant fraction of planets that are scattered to the outer Oort cloud. Even though such an Oort cloud population can not explain the proposed Planet Nine, long-lived ice giant planets detectable through current methods may exist in the distant Oort cloud.