NASA announced today the discovery of the largest collection of earth-like planets ever found orbiting a single star. The exoplanet system, known as TRAPPIST-1, is named for the The Transiting Planets and Planetesimals Small Telescope (TRAPPIST) in Chile, which initially identified three of the planets in the system in 2016. NASA's Spitzer Space Telescope, assisted by several ground-based telescopes, including the European Southern Observatory's Very Large Telescope, is responsible for confirming two of the planets initially discovered, and identifying five more, bringing the total number of known planets in the system to seven.

News of the discovery will be printed in the journal Nature, and revealed in a press release by NASA. The discovery does not yet show any evidence of extraterrestrial life, but does show potentially habitable worlds.

"The seven wonders of TRAPPIST-1 are the first Earth-size planets that have been found orbiting this kind of star," said Michael Gillon, lead author of the paper and the principal investigator of the TRAPPIST exoplanet survey at the University of Liege, Belgium. "It is also the best target yet for studying the atmospheres of potentially habitable, Earth-size worlds."

Of the seven planets discovered, three are in the system's 'Goldilocks Zone' thought to be necessary for life to exist. The exact potential for life on the planets is not yet known, but further data from the Spitzer Space Telescope will help determine if it's a possibility.

“This discovery could be a significant piece in the puzzle of finding habitable environments, places that are conducive to life,” said Thomas Zurbuchen, associate administrator of the agency’s Science Mission Directorate in Washington. “Answering the question ‘are we alone’ is a top science priority and finding so many planets like these for the first time in the habitable zone is a remarkable step forward toward that goal.”

"The discovery shows us that finding a second Earth is not a matter of if, but a matter of when."