Nevertheless, what if the hypothetical Planet Nine has moons?

By Michelle Starr

February 12, 2023

 Evidence from recent years points to the possibility of something enormous and perhaps very dark hiding on the solar system's periphery.

The existence of that big, dark planet, called Planet Nine, is suggested by several oddly clustered orbits seen in small objects in the Kuiper Belt of the outer solar system. According to some experts, something triggered a gravitational disruption that resulted in the formation of these orbits.

Whatever it is, according to their estimations, the object's mass is between 5 and 10 times that of Earth.

However, because the outer solar system is so far away, it is exceedingly difficult to see anything there. If Planet Nine exists, it should be orbiting the sun at a distance between 400 and 800 times that of Earth. Therefore, despite extensive searches by scientists, no one has yet found Planet Nine.

This might be the case, for instance, if Planet Nine is a dark object, such as a black hole. Such a black hole would not only not emit any light, but it would also be incredibly small—practically undetectable even if it could reflect light.

However, according to astronomer Man Ho Chan of the Education University of Hong Kong in China, we still might be able to find it.

He argues that a slew of moons orbiting the enigmatic lump of material could be the smoking gun in a study under review at The Astrophysical Journal and published to the preprint server arXiv.

The possibility of Planet Nine catching big trans-Neptunian objects (TNOs) to create a satellite system in the dispersed disc region (between the inner Oort Cloud and Kuiper Belt) is demonstrated in this article, according to Chan.

By using a benchmark model of Planet Nine, we demonstrate that even if Planet Nine is a dark object, the tidal action can dramatically heat up the satellites, providing enough thermal radio flux for measurements.

There is at least one moon on almost every planet in the solar system. In actuality, the majority have many. The only planet with just one satellite is Earth; Mercury and Venus don't have moons. Non-planetary bodies can also have moons. Of course, Pluto has its own moons. even have moons on some asteroids.

Moons are essentially popular in the middle to outer Solar System. Some, like the moon of Earth, might have developed from the parent body's own material. In numerous other instances, the planet's gravity ensnared passing boulders and retained them, like strange little goblins who collect rocks.

It turns out that the region between the rocky Kuiper Belt and the rocky Oort Cloud, where Planet Nine is anticipated to be, should be ripe for the moon-picking. Trans-Neptunian objects, which are essentially rocks with orbits that are farther from Neptune on average, should be present in this area, which is referred to as the scattered disc.

Chan determined that it would be more bizarre if the alleged planet hadn't picked up any satellites after calculating the likelihood that it might have done so. He determined that an object the mass of Planet Nine should typically be able to trap 20 trans-Neptunian objects that are at least 140 kilometres (87 miles) broad.

If the moon were huge enough, say greater than 100 kilometres in diameter, a gravitational interaction with a more massive body might change that, making these frozen rock fragments observable.

Orbits of captured satellites are typically erratic and elliptical. The moon is stretched out where the planet's gravitational pull is highest because the gravitational forces put on it alter as it approaches and recedes from the planet.

The moon is heated within by these varying tensions. and thermal radiation is used to dissipate heat. This should be audible as a radio signal, and we can look for it right away, claims Chan.

"Our proposal can directly observe the potential thermal signals emitted by the satellites now," he writes. "If P9 is a dark object and it has a satellite system."

As a result, this would be a quick and efficient way to confirm the Planet Nine hypothesis and determine whether or not Planet Nine is a dark object.