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Rogue Planets: The Wanderers of Milky Way Without Stars

By Satabdi MazumdarNovember 08, 2022
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What are Rogue Planets Found in the Milky Way?


Imagine waking up to the news that our Solar System is visited by a wandering planet. It seems to be a plot from Hollywood movies. Scientists have found and located nomad planets that do not have a home like ours. They wander in our galaxy and we wonder what they are!

These rogue planets are found in the new areas discovered in space. Researchers have been watching them for years to trace their paths and to find out whether they have a guiding star like our sun. They actually don’t have any. Let us know more about this fascinating celestial topic.

What are Rogue Planets?

From the name, you can clearly understand that these planets do not follow any particular path. What are these celestial bodies then and why are calling they planets? Well, here is the story.

In December 2020, the European Southern Observatory (ESO) was doing its work as usual. This observatory has a set of enviable powerful telescopes that can see through unknown spaces in the universe. These telescopes recognized a few celestial bodies that are not stars but planet-like structures.

Núria Miret-Roig, an Austrian astronomer found multiples of such celestial bodies roaming in the Milky Way, our galaxy. She discovered a cluster of such planets and made us wonder. The team of astronomers she led was baffled by this discovery.

Every admirer of astronomy was surprised to find such planets that do not follow a proper path around a star. According to the general convention, a planet that is formed close to a star always remains under its gravitational field. The star’s gravitational field makes a planet follow an elliptical path to revolve.

On the other hand, these newly discovered planets are nomadic in nature. The astronomers had to create a new definition to answer what is a rogue planet. According to them, a planet that does not follow an orbit nor has a star to follow is called a rogue planet.

This team of astronomers in Austria found nearly 70 such celestial bodies and called them nomad planets. They are roaming in the galaxy on their own and certainly don’t follow specific orbits. It means these planets are not parts of a star system and don’t follow such rules.

We have discovered rogue planets before but in such clusters. This finding was marvelous and it literally opened a new segment in astronomy. These rogue planets are the largest find in the history of astronomy.

An Artistic Impression of Rogue Planets

An Artistic Impression of Rogue Planets 

Also Read- Amazing Facts About Our Planet Earth

How these Nomad Planers were found?

These planets were lurking around for millions of years but we did not notice. As already mentioned, they do not follow a star. It means they do not follow any specific path. Hence, the location of the rogue planets is hard to detect. Their erratic paths are rhythmless and cannot be traced properly.

On the other hand, planets do not produce light of their own. They are illuminated by the nearest star. As these planets do not have stars nearby, they will not have ample light to reflect that can be detected. Then, how did these planets get detected?

You will be surprised to know that these planets are quite young when compared to the planets of our Solar System. They are still hot and emit radiation in different forms. This faint radiation can only be detected by the strongest telescopes we have.

Scientists accumulated data that was gathered for two long decades from several observation grounds and space telescopes. These precise instruments are present in the European Space Observatory (ESO) in Germany and Chile and the Gaia satellite of the European Space Agency (ESA).  

Astronomers observed faint light emissions and motion of unidentified objects near the Ophiuchus and Scorpius Constellations near our Solar System. These new discoveries in the area of space near these constellations amazed the world of astronomy. The estimation made from the data available makes these planets much bigger than Jupiter.

While 70 of them have been detected, scientists speculate that they might be 170 or more in number. Astronomers are now working on theories related to the origin of the rogue planets. These theories may unravel things about our galaxy and the universe we did not know of.

The History of the Discovery of Rogue Planets

It was in 2012 that scientists first detected a rogue planet. They used a method called microlensing. This new rogue planet detection method involves watching the foreground objects that move in front of the stars in the background. A phenomenon of bending of light occurs when light passes over these planets due to gravity. The rate of bending can be calibrated to find and identify these nomad planets along with their mass.

The first-ever found rogue planet is 100 light years away from the earth. It is named CFBDSIR2149. The next discovery dates back to October 2020 when astronomers spotted an earth-sized planet.

Could Rogue Planets have Life?

Well, it is hard to detect life using our powerful telescopes. We are working on the origin of these planets and how they are flying solo in the galaxy.  We can find out whether these planets have life only when we land an astrobiological robot on them.

Are We in Danger due to Rogue Planets?

These planets do not pose a threat to our existence. They are quite far away from us. Apart from the new discoveries in Solar System, scientists across the world have collaborated to find out more answers regarding these planets.

They seem harmless and very young. The questions of their origin and their starless navigation in the galaxy baffle us more. We will need better telescopes and exclusive detection methods to find more of them and to conclude how they have formed. Who knows we might be able to answer certain questions related to the formation of our galaxy?