Exoplanet Discovery: Researchers Confirmed The Exact Orbit Of Outer Trappist Planet

Researchers now know more about the Trappist-1 exoplanet discovery, specifically the most mysterious Trappist-1h and its orbit. The seven Earth-size planets orbit the Trappist-1 star that’s about eight percent the size of our sun and located in the Aquarius constellation about 40 light-years away from Earth.

The planets were announced in February, a significant discovery for their potential to possibly host life. Three of the planets are within the habitable zone of the star, meaning they may have liquid water on a possibly rocky surface. But when these planets were announced their orbits weren’t confirmed. Now researchers are confident in how long each planet takes to orbit the distant star.

Read: NASA Trappist Discovery Announcement: 40 Light Years Away, Earth-Size Planets That Could Have Water Found

Thanks to data collected by the Kepler spacecraft, astronomers from the University of Washington were able to determine that the Trappist-1h exoplanet orbits the Trappist star once every 19 days, according to NASA. The planet sits outside the habitable zone, meaning it’s probably far too cold to support the type of life we know to exist. The finding is important however because it confirms beliefs NASA held about the location of the planet.

The six inner planets stay in place due to orbital resonance, which means they all have a slight gravitational pull on one another as they orbit the star together. This means the researchers were able to study the planets before Kepler data was available and estimate the orbit of 1h by using the orbital velocity of the surrounding planets.

In the video model above, planet Trappist-1h is traveling on the outer track, the seventh one from the center where the star would be. The orbital resonance can be seen each time the three planets align. The video pauses briefly to show the planets in their aligned positions before continuing on.

Read: You Could Make The Next Exoplanet Discovery With This New Game

Data from the Kepler spacecraft was not released until March 8, a few weeks after the Trappist announcement was made. But once it was released scientists from around the world began working on it. With this type of worldwide teamwork, a 19-day orbital prediction was made within two hours of the data’s release, NASA said. When the Trappist planets were first discovered, it was thought there were just three planets, but as more telescopes were added into the research, it was revealed the system held seven planets. This made them the most planets to hold a chain of resonance.

"It really pleased me that Trappist-1h was exactly where our team predicted it to be,” Rodrigo Luger, the lead author on the study published on the finding told NASA. “It had me worried for a while that we were seeing what we wanted to see — after all, things are almost never exactly what you expect them to be in this field.” The findings were published in Nature Astronomy Monday.