UPSC PRELIMS 2019 : They’re Not Moons. They’re Not Planets. They’re Ploonets

They're Not Moons. They're Not Planets. They're Ploonets

Topic: They’re Not Moons. They’re Not Planets. They’re Ploonets

Topic in Syllabus: Science & Technology

 

Context:

They're Not Moons. They're Not Planets. They're Ploonets

Astronomers have defined a new class of celestial objects called “ploonets,” which are orphaned moons that have escaped the bonds of their planetary parents.

 

Ploonets:

Astronomers named a new class of theorized objects that begin as moons around large planets, but eventually move out on their own. They call them “ploonets.”

Planet + moon = Ploonet.

 

Where do they exist?:

The scientists think these objects should exist in solitary orbits around their host stars and could even be discovered in observations from past and present exoplanet-hunting surveys, like Kepler and TESS.

 

Making of a Ploonet

The researchers explain that the angular momentum between the planet and its moon results in the moon escaping the gravitational pull of its parent.

A new study suggests that the moons of gas-giant exoplanets may break away into their own orbits.

As the gas giants move inward toward their suns, the orbits of their moons are often disrupted, according to new computer models.

 

Findings:

Over the past few decades, astronomers have uncovered more than 4,000 confirmed exoplanets, and nearly as many exoplanet candidates.

And one thing astronomers have learned from this sizeable census is that a surprisingly high number of massive exoplanets — called “hot Jupiters” — are located oddly close to their host stars.

Although at least part of the reason they detected so many hot Jupiters boils down to observational biases, this significant sample of weird planets still raises questions about how planets form.

 

Have we already found Ploonets?

Although there has yet to be a definite confirmation of a Ploonet orbiting a star, there are at least a few examples that might fit the bill.

The evidence for these potential Ploonets comes from perplexing exoplanetary observations that have yet to be adequately explained.

 

Earth’s Moon:

Earth’s own Moon is slowly spiraling away from our planet; it may also end up as a ploonet in some 5 billion years.

 

Sample Question:

‘Ploonets’ refers to

a) Moon

b) Comets

c) Lakes created by a meteor impact

d) Trans-Neptunian Objects

 

Solution (a)

Astronomers named a new class of theorized objects that begin as moons around large

planets, but eventually move out on their own. They call them ploonets.