TRAPPIST-1

Discovery using the Spitzer inferred Space Telescope in 2016.

TRAPPIST-1 is a "Ultra cool" dwarf star located about 39 light-years from Earth is only slightly larger than the planet Jupiter and about 2,000 times dimmer than our sun, It harbours at least 7 tidally locked planets 3 of which in the Habitable Goldilocks Zone.

Climate models suggest that the three closest to the star would likely be too hot for liquid water to exist “on any more than a small fraction of their surfaces,” according to the European Southern Observatory. The furthest planet is too cold for water but temperatures may be just right on the other three planets TRAPPIST-1 (e, f and g) all 3 being roughly the size of Earth and may be capable of supporting life as long as they have atmospheres that can transport heat from the day side to the night side.

Credit: NASA/JPL-Caltech

Trappist 1 System

All seven alien worlds occupy tight orbits, lying closer to TRAPPIST-1 than Mercury does to the sun. The orbital periods of the innermost six worlds range from 1.5 days to 12.4 days; the outermost planet, known as TRAPPIST-1h, is thought to complete one lap in about 20 days.

Triaud said "Because of the star's dimness, even daytime skies would never get brighter than Earth's are just after sunset. (Still, the air would be warm, because most of TRAPPIST-1's light is radiated in infrared, not visible, wavelengths.) And everything would be suffused in a sort of salmon-coloured glow."

All six inner planets are rocky, like the Earth; not enough is yet known about planet h to determine its composition and will need to wait until NASA's $8.8 billion James Webb Space Telescope is launch in late 2018.

Currently fastest flight time is 800,000 years.