(WFLA) — An Earth-sized planet orbiting its star’s habitable zone has been discovered by NASA.

The planet, called TOI 700 e, is 95% Earth’s size and likely rocky, NASA said Tuesday. It’s the second planet found in the habitable zone of the TOI 700 system. Scientists discovered TOI 700 d in 2020, which is on a 37-day orbit.

Two other planets were discovered in the same system, called TOI 700 b and c.

“This is one of only a few systems with multiple, small, habitable-zone planets that we know of,” said Emily Gilbert, a postdoctoral fellow at NASA’s Jet Propulsion Laboratory in Southern California who led the work. “That makes the TOI 700 system an exciting prospect for additional follow up. Planet e is about 10% smaller than planet d, so the system also shows how additional TESS observations help us find smaller and smaller worlds.”

NASA said the planets are probably tidally locked, which means they spin only once per orbit and one side of the planet faces the star.

Scientists believe the newly discovered planet, TOI 700 e, may also be tidally locked. It takes 28 days to orbit its star, which placed it in the so-called optimistic habitable zone.

NASA said the optimistic habitable zone is the range of distances from a star where liquid surface water could be present at some point in a planet’s history.

Finding other systems with Earth-size worlds in the region helps planetary scientists learn more about our own solar system, NASA said.