Alien Life: NASA finds three new worlds close to Earth which could harbour life

Scientists have characterised first potentially habitable world outside our own solar system located about 31 light-years away.

Earth-like Super planet

super-Earth planet -- named GJ 357 d -- was discovered in early 2019 owing to NASA's Transiting Exoplanet Survey Satellite (TESS), a mission designed to comb heavens for exoplanets, according to research published in Astrophysical Journal Letters.

"This is exciting, as this is humanity's first nearby super-Earth that could harbour life -- uncovered with help from TESS, our small, mighty mission with a huge reach," said Lisa Kaltenegger, associate professor of astromy at Cornell University in US and a member of TESS science team.

exoplanet is more massive than our own blue planet, and Kaltenegger said discovery will provide insight into Earth's heavyweight planetary cousins.

"With a thick atmosphere, planet GJ 357 d could maintain liquid water on its surface like Earth, and we could pick out signs of life with telescopes that will soon be online," she said.

Travel: NASA Ropes In Elon Musk's X To Develop Tech To Refuel Ships In

Astromers from Institute of Astrophysics of Canary Islands and University of La Laguna, both in Spain, anunced discovery of GJ 357 system in journal Astromy & Astrophysics. y showed that distant solar system -- with a diminutive M- dwarf sun, about one-third size of our own sun -- harbours three planets, with one of those in that system's habitable zone: GJ 357 d.

TESS' previous discoveries

Last February, TESS satellite observed that dwarf sun GJ 357 dimmed very slightly every 3.9 days, evidence of a transiting planet moving across star's face. That planet was GJ 357 b, a so-called "hot Earth" about 22 per cent larger than Earth, according to NASA Goddard Flight Center, which guides TESS.

Follow-up observations from ground led to discovery of two more exoplanetary siblings: GJ 357 c and GJ 357 d.

international team of scientists collected Earth-based telescopic data going back two deces -- to reveal newly found exoplanets' tiny gravitational tugs on its host star, according to NASA. Exoplanet GJ 357 c sizzles at 127 degrees Celsius and has at least 3.4 times Earth's mass.

However, system's outermost kwn sibling planet -- GJ 357 d, a super-Earth -- could provide Earth-like conditions and orbits dwarf star every 55.7 days at a distance about one-fifth of Earth's distance from sun. It is t yet kwn if this planet transits its sun.

Mini Sun: US Scientists Recreate 'Sun' In ir Laboratory To Study Solar Winds

Scientists predict water presence

Kaltenegger, doctoral candidate Jack Mden and undergruate student Zifan Lin simulated light fingerprints, climates and remotely detectable spectra for a planet that could range from a rocky composition to a water world.

"We built first models of what this new world could be like. Just kwing that liquid water can exist on surface of this planet motivates scientists to find ways of detecting signs of life," Mden said.

"If GJ 357 d were to show signs of life, it would be at top of everyone's travel list -- and we could answer a 1,000-year-old question on wher we are alone in cosmos," Kaltenegger said.