Exoplanets and its understanding

In recent times, I have been listening about new discovery of Exoplanets by the astronomers. I always have the curio towards the discovery of aliens and the life on other planets. Are you also curious about life on other planet? Join me in the expedition of Space travel to Exoplanets and its understanding.

A question every Science student who study Science ask is whether there is life on other planet are we alone? My curiosity regarding Aliens increased after watching Hollywood movies, where they show aliens as an ugly form of creatures.

Beside this, some YouTube videos which have the content regarding alien abducting humans, like Men in black movie franchise.

As per our knowledge regrading our solar system, we have only eight planets. What are these Exoplanets? To know this read further.

Exoplanets and its understanding

There are other planets in the universe apart from our eight planet and sub planets(like Pluto) and their Moons. The astronomers with help of powerful telescopes found few planets beyond our Solar system which are commonly called Exoplanets. Exo means outside the solar system planets.

Generally all the planets irrespective of their nature, rocky or gaseous, rotate around the star similar to our solar system where all the eight planets revolve around the sun.

Till now they found thousands of exoplanets in just 2 decades and the count keep increasing. There are few exoplanets which are similar to the planets in solar system, for example few are rocky, icy and gaseous.

Methods of finding Exoplanets

How astronomers identify the exoplanets? Almost every planet in the universe receives light from the Star which is revolving around it. But the light on the exoplanets are dim, they aren’t as bright as the light on Earth.

Radial velocity method

This method looks similar to the gravitational force concept. Based on the Doppler effect they found numerous exoplanets. This method came into implementation in 1990’s.

Instead of complicating thing, let’s understand this in simple terms : Change in wave frequency during the relative motion between a wave source(star) and its observer(exoplanet).

Still confused? In simple words when a planet comes near or move far from the star, the color of star changes either red or blue as the wavelength of light shift based on the Doppler effect.

By observing the change in color of the star, astronomers found few exoplanets presence near the far away stars.

Transit method

Kepler is the name of Space craft used by NASA in search of Exoplanets. They found few Exoplanets by just observing from Earth using Transit method.

They identified exoplanets based on the light rays dimming from the star. when a planet revolve around the star, it partially blocks the light on the star by dimming it. We can say it is a planet which is blocking the light on the star.

Direct Imaging method

It is another method to identifiy the Exoplanets. During the hunt for Exoplanet, astronomers never take any chances. Few times they track the dim images and follow its orbit. The faint image which found near stars turns out to be Exoplanets.

These exoplanets are divided into five different categories :

Hot Jupiter

Super earth

Mini Neptune

Ocean world

Ice giants

Life on Exoplanets

Till now there has been no luck in this field. Astro-biologists are keenly working on to find a life on these identified Exoplanets. They looking for microbes to confirm life on the planets.

The famous equation they use to find life on other planets is “Dark Equation”.

So my dear readers, a small question, Do you Think we are alone ? write your thoughts in the comments section.

https://earthsky.org/astronomy-essentials/what-are-exoplanets/