An astrophysics researcher, Billy Quarles, has identified the possible compositions of the seven planets in the TRAPPIST-1 system. By studying the compositions of "thousands of numerical simulations to identify the planets stable for millions of years, Quarles concluded that six of the seven planets are consistent with an Earth-like composition," science journal Phy.org reported. The exception is TRAPPIST-1f, which has a mass of 25 percent water, signifying that TRAPPIST-1e may be the best candidate for future habitability studies. In May last year, astronomers from MIT announced the discovery of an extremely unusual star system in the nearest region of Earth — TRAPPIST-1, which is only 40 light-years away from Earth in the direction of the constellation of Aquarius. It was reported then that three planets revolving around this red dwarf, which presumably have a mass comparable to that of earth, are inside the so-called "zone of life" where water can exist in liquid form. The