Everything you need to know about TRAPPIST - 1

In February 2017, NASA blowed everyone's mind with the shocking discovery of seven earth sized planets revolving around a star smaller than our Sun. This discovery filled our hearts full of joy and excitements which also brought a common question popping in our head 'ARE WE ALONE IN THE UNIVERSE?' Although we don't have any answer for that question, lets find out what we have discovered and the things NASA has revealed about the newly discovered planetary system.

TRAPPIST-1 Planetary System

TRAPPIST-1 is a planetary system, located 39 light years away from the Solar system, near the ecliptic, within the constellation of Aquarius. There are at least seven planets in the orbit around a star which is 12 times less massive than the Sun and only slightly larger than Jupiter. The initial discovery was made by TRAPPIST, the TRAnsiting Planets and PlanetesImals Small Telescope. Additional planets were subsequently identified using TRAPPIST and the Spitzer space telescope, the Very Large Telescope, UKIRT, the Liverpool Telescope and the William Herschel Telescope.

The main star is named as Trappist-1A and the planets are named as Trappist-1B, Trappist-1C, and so on up to Trappist-1H respectively going from the planet nearest to the star to farthest. All the planets in the TRAPPIST-1 system transit their star, meaning that they pass in front of it and are very close to each other. The planets were discovered from the regular and repeated shadows that are cast during transit. NASA has even measured the orbital periods and calculated the sizes of the planets. The exact time at which the planets transit also provide us with a means to measure their masses, which leads to knowing their densities and therefore their bulk properties. The planets are consistent with a rocky composition.

It is known that the planets have sizes and masses comparable to the Earth and Venus and they receive an amount of light that is similar to many of the planets in the Solar system, from Mercury to beyond Mars. During transit, some of the starlight goes through the atmosphere of the planets, getting transformed by the chemical composition of the atmosphere and by its vertical structure. This means that we can remotely study the climates of terrestrial worlds beyond our Solar system! The TRAPPIST-1 worlds are the most optimal currently at our disposal. They are providing humanity with it first opportunities at discovering evidence of biology beyond the Solar system.

WHY IS TRAPPIST-1 SO IMPORTANT?

1. It is easier to survey stars that have masses less than 15% the mass of the Sun, for planets. TRAPPIST-1A, the star at the centre of the TRAPPIST-1 system, is representative of our sample since the star is M-Dwarf Star (smaller and much cooler than our Sun). These objects may appear exotic in comparison to our Sun, however they provide various advantages for the study and the understanding of Earth-like planets.
2. M-Dwarf stars are the most frequent kind of star in the Galaxy. Finding planets orbiting those stars is akin to study the most common planets that exist, which is essential to understanding the formation of Earth-like planets. They are also crucial in order to one day establish with what frequency biology has emerged in the Cosmos. M-Dwarf stars have the the most chance of supporting life among all other stars due to various factors. M-Dwarf star burns slowly up to trillion of years and burns emitting low amount of sun. And if this star in TRAPPIST system is burning for many years then there is possibility that life has already started in some of those planets or at least we can be sure of life in near future (considering the star only).
3. All the planets orbiting the star in TRAPPIST-1 have their radius in between 0.75 to 1.08 times of earth which is pretty close to our earth and are formed by rocks which is also similar to earth's surface. Among the seven planets, E, F and G lie in a habitable zone i.e. they lie in a place where the temperature is mild and formation of liquid water is possible. However, the only problem may be since all the planets in the system are suspected to be tidally locked which means their orbital period matches their rotational period causing them to face towards the star from one face only like our moon. But, since they all revolve around the star at distance less than mercury revolves around the sun, this may not cause a big problem as the planet will be at mild temperature.
4. Finding planets orbiting ultra-cool dwarfs means that we find planets similar to our Earth on several aspects, but different on several others. For instance, the amount and type of light the planets receive is not the same as what we receive on Earth. Also the proximity of the TRAPPSIT-1 planets to their star means that they are likely to be tidally-locked. This signifies that there is a permanent dayside and a permanent nightside. How this affects climate remains mostly unknown. Planets like those of TRAPPIST-1 will open the study of what appears to our eyes like exotic climates, but that may in fact be some of the most usual climates outside the Solar system.

James Webb Space Telescope

The James Webb Space Telescope (JWST), previously known as Next Generation Space Telescope (NGST) is going to be launched by NASA in October 2018 for the further study of TRAPPIST-1 system and we will surely hear some more exciting news from NASA in near future. Lets just hope NASA won't disappoint us. What do you think about the newly discovered planetary system? Please let me know in the comment below.