Ploonets: Exiled moons may explain astronomical mysteries

**Ploonets: Exiled moons may explain astronomical mysteries
Did Jupiter once have ‘ploonets’? Credit: Original Image: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute/Goddard Space Flight Center

Moons ejected from orbits around gas giant exoplanets could explain several astronomical mysteries, an international team of astronomers suggests.

Researchers led by Mario Sucerquia, from the Universidad de Antioquia, Colombia, and Jaime Alvarado-Montes from Australia's Macquarie University, modelled the likely behaviour of giant exomoons predicted to form around —and discovered that they would be expelled and sent packing.

Roughly 50 percent of these ejected moons would survive both the immediate expulsion and avoid any subsequent collision with the planet or the star, ending up as quasi-planets travelling around the , but in eccentric "Pluto-like" orbits.

These rogue moons—dubbed "ploonets" by Sucerquia, Alvarado-Montes and colleagues—could potentially explain several puzzling phenomena, not the least of which is why astronomers have so far confirmed the existence of at least 4098 exoplanets, but not a single exomoon.

Most of the planets discovered thus far are of a type known as Hot Jupiters, a fact that reflects mainly the limits of current detection technology. Previous research indicates that at least some of these should be orbited by large moons.

Their absence, the researchers write in a paper soon to be published in the journal Monthly Notices of the Royal Astronomical Society, could be explained by a scenario in which the between the two bodies results in the escaping the gravitational pull of its parent.

"These moons would become planetary embryos, or even fully-fledged , with highly eccentric orbits of their own," explains Alvarado-Montes.

While conceding that ploonets remain hypothetical, the researchers say their existence would offer a for several challenging results produced by NASA's now-retired Kepler space telescope.

These include the puzzling dips in the light-curves emanating from a formally known as KIC-8462852.

"It's better known as Tabby Star," says Alvarado-Montes, "and the strange changes in its light intensity have been observed for years, but are still not understood. Ploonets could be the answer."

They might also explain apparent evidence of cannibalism between some , or the existence of "exocomets" around others.

Ploonets, thus, may be a vital piece of the planetary puzzle, but, as yet, their existence remains unproven.

Sucerquia, Alvarado-Montes and colleagues concede that even if they do exist, they may deteriorate too rapidly to ever be observed.

"If, on the other hand," they write, "the timescales are large enough, we could have real chances to detect them in the near and middle future."

The paper, "Ploonets: formation, evolution, and detectability of tidally detached exomoons," is currently available on arXiv, the preprint library maintained by Cornell University in the US.


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More information: Mario Sucerquia et al. Ploonets: formation, evolution, and detectability of tidally detached exomoons. arXiv:1906.11400v1 [astro-ph.EP]: arxiv.org/abs/1906.11400
Citation: Ploonets: Exiled moons may explain astronomical mysteries (2019, July 12) retrieved 17 October 2019 from https://phys.org/news/2019-07-ploonets-exiled-moons-astronomical-mysteries.html
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Jul 13, 2019
@Castrogiovanni
@cantdrive85.

Does the above have any effect on your mutual longstanding (ahem) differences over the claim that Venus (or was it Earth?...I forget) once orbited Saturn (or was it Jupiter?...I forget that too)? I would be interested to hear your respective views in light of the above. Now play nice, guys; just say your (polite) piece on the matter and leave it at that without the usual animus/insults. Ok? Thanks. Good luck. :)

Jul 14, 2019
Jupiter and Venus Are Warping Earth's Orbit, Linking to Major Climate Events

Scientists have confirmed a longstanding hypothesis
That Earth's orbit is warped
By the gravitational pull
Of Jupiter and Venus
In an epic cycle that repeats regularly every 405,000 years
https://www.scien...nkovitch

Venus Came out of Jupiter - Worlds in Collision
Around the 15th century BC
The planet Venus
Was ejected from Jupiter
As a comet
Or comet-like object
Passed near Earth
The object allegedly changed Earth's orbit and axis
Causing innumerable catastrophes
That is mentioned in early mythologies
And religions from around the world

And now on top of this we have Ploonets
Tidally detached exomoons
Exoplanet's that were formerly moons
Of another planet
Ejected from their orbits
Around their parent planets
By tidal forces during planetary migration
Becoming planets in their own right

Venus Came out of Jupiter or Ploonets

Jul 14, 2019
@granville
Don't be too hasty now. The article clearly says that, "...as yet, their existence remains unproven."
Give them some slack.

Jul 15, 2019
When Ploonets Exist

Worlds in Collision - By Immanuel Velikovsky
SEU> @granville
Don't be too hasty now. The article clearly says that, "...as yet, their existence remains unproven."
Give them some slack.

It must be all these lectures we regularly receive on that Russian scholar, Immanuel Velikovsky
Ploonets when found effect planetary weather cycles as Jupiter and Venus are
For
Venus came out of Jupiter fitted Ploonets to a T
Ploonets fits nicely in worlds in collision by Immanuel Velikovsky
When Ploonets are found add credence to Immanuel Velikovsky and make a gripping planetary saga

p.s. SEU, there is something indefinably satisfying adding credence to Immanuel Velikovsky that makes this gripping planetary saga all the more intriguing

Jul 15, 2019
This Moonchine Ploonet

SEU, our moon orbiting planet earth
Is incrementally
Increasing its orbital radius
That given time will one day leave earth
For our moon is clearing its orbit
In years to come our moon will be a planet in its own right
Our moon will become a Ploonet

Jul 17, 2019
When that time comes for Luna to leave her orbit around her Mama, I don't think that humans or animals will survive the loss. Before the making of our Moon billions of years ago, there were no tides; no subduction; no pulling apart of platelets; very few earthquakes; and no deep sea trenches. The Earth was smooth with very few hills and no mountains. All was tranquility, until that fateful day when Mama gave birth to Luna. It was a sad parting, but Luna promised to look in on her Mum often. And so she does - every single night.

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