Astronomers have recently discovered three habitable planets, "super-Earths" that may harbor life, orbiting a nearby star.

Scientists discovered three new habitable planets in the habitable zone of the star Gliese 667C. The planets are in the zone where liquid water could exist and have atmospheres that may hold oxygen. They're also in stable orbits, which is important to harbor life.

This is the largest discovery of habitable planets found to date. It is the first system found with a habitable zone that is fully packed. The habitable zone refers to the area that is far enough from the sun to be warm but not so far away as to be frozen. Thus, they are in the zone that may have water and are of the right size to harbor life-"super-Earths" that are a bit larger than Earth but not massive.

The star the new planets orbit around is well-studied, but scientists at the European Southern Observatory decided to look at it again made a surprising discovery.

There are several other new planets orbiting the same star that were also previously undiscovered. However, the other new planets are unlikely to harbor life.

"We knew that the star had three planets from previous studies, so we wanted to see whether there were any more," Mikko Tuomi of the University of Hertfordshire, UK told press. "By adding some new observations and revisiting existing data we were able to confirm these three and confidently reveal several more. Finding three low-mass planets in the star's habitable zone is very exciting!"

The team combined new observations with existing data from HARPS at ESO's 3.6-meter telescope in Chile. Their measurements revealed a system with at least six planets, and three of the planets are Super-Earths that exist where water could exist. This discovery is the largest number of potentially habitable planets found in one system to date.

"The number of potentially habitable planets in our galaxy is much greater if we can expect to find several of them around each low-mass star -- instead of looking at 10 stars to look for a single potentially habitable planet, we now know we can look at just one star and find several of them," study co-author Rory Barnes of the University of Washington wrote.

The new planets orbit the faintest star of a triple-star system. The super-Earths are bigger than Earth, but smaller than huge planets like Uranus and Neptune. If conditions are right, liquid water could exist.