NASA’s Spitzer Space Telescope has discovered seven Earth size planets revolving around a single star. They are located in the habitable zone which is warm enough for water and life to sustain.
This new discovery have thrilled the astronomers as this is record finding for the greatest number of such planets. They are about 40 light-years (235 trillion miles) from Earth, and are in the constellation Aquarius. Called as exoplanets as they are located outside our solar system.
This exoplanet system is called TRAPPIST-1,as it is the Transiting Planets and Planetesimals Small Telescope (TRAPPIST) in Chile. Based on their densities, all of the TRAPPIST-1 planets are likely to be rocky. Further study of the atmosphere can reveal if there is presence of liquid in them.
In contrast to our sun, the TRAPPIST-1 star is cooler but planets which are close to it can have liquid water survive. All seven of the TRAPPIST-1 planetary orbits are closer to their host star than Mercury is to our sun.
Spitzer, an infrared telescope that trails Earth as it orbits the sun, was well-suited for studying TRAPPIST-1 because the star glows brightest in infrared light, whose wavelengths are longer than the eye can see.