Researchers from the European Southern Observatory discovered three Earth-like Exoplanets orbiting a nearby Red Dwarf Star.
According to a report published on Monday, May 2, in the British journal, ‘Nature’, the Exoplanets were found 40 light years, or 386 million kilometres, away from us in the Milky Way.
This might sound far away but in cosmological terms it’s almost in our stellar neighbourhood. After all, our Milky Way extends to about a 100 thousand light years in diameter.
The exciting thing about this discovery is that not one but three planets were found in the Goldilocks Zone of the star TRAPPIST-1.
This means that it is highly probable that these planets could have surface water in liquid form, which is the essential ingredient for life as we know it.
Although there are a large variety of planets which can exist according to our laws of physics, there is a special class of exoplanets which grasp our attention more than anything else.
Earth like exoplanets are planets which are similar in size and temperature to that of Earth’s and can potentially be birthplaces for living organisms much like the ones found on Earth.
The study published in ‘Nature’ found that two of the planets have orbital periods of about 1.5 days and 2.4 days respectively, and the third planet has a less well determined period in the range of 4.5 to 73 days.
Astronomers focused the Belgian TRAPPIST telescope on the star now known as TRAPPIST-1, a Jupiter-sized star in the constellation Aquarius that is one-eighth the size of our Sun and significantly cooler.
The planets were found by calculating the dim in the brightness of the star as the planets passed in front of it, blocking some of its light.
By measuring how much light is blocked, astronomers can calculate the size of the planets. A red dwarf is a type of star which is much cooler than our Sun, and the Milky Way galaxy is full of them.
Once the astronomers know the size of the planet they can predict its distance from the star and thereby predict its surface temperature.
Red dwarfs emit most of their energy in the form of infrared radiation suggesting that if life exists on these planets then it might have evolved by drawing energy from infrared rays.
About 20 years ago, astronomers around the world weren’t even sure that planets existed outside our solar system, but in the last few years we have found more exoplanets than in all of human history.
It is predicted that on an average every star in our Milky Way has about 1.6 Earth-like exoplanets which orbit their star. With about 300 billion stars in our galaxy, that’s almost 500 billion Earth-like planets in Milky Way alone. And the observable universe has about 100 billion galaxies!