An artist's illustration shows the new largest planet in the Kepler-88 system, Kepler-88 d, which is estimated to have three times the mass of Jupiter. Image by Adam Makarenko/W.M. Keck Observatory
April 29 (UPI) -- Astronomers have discovered a massive exoplanet three times the mass of Jupiter in Kepler-88, a planetary system anchored by a sun-like star in the constellation of Lyra, located roughly 1,240 light-years from Earth.
Like Jupiter, scientists suspect the newly discovered exoplanet, Kepler-88 d, has a strong gravitational influence on the system's other two exoplanets.
The Kepler-88 system was already well-known to astronomers due to the unusual orbital pattern of the stellar system's inner two planets, Kepler-88 b and Kepler-88 c.
The orbits of the system's inner two planets follow an orbital pattern called mean motion resonance. The small, inner-most planet orbits Kepler-88 every 11 days. The second planet, a Jupiter-mass planet, takes twice as long, 22 days, to complete an orbit.
The orbital pattern of the two planets is extremely energy efficient. On every other go around the sun, Kepler-88 b gets a gravitational boost from its big brother, Kepler-88 c, which is twenty times more massive.
Each time the two planets pass, their orbits become altered -- phenomena known as transit timing variations. Kepler-88 b and Kepler-88 c feature some of the largest transit timing variations observed in the universe.
After surveying six years of data captured by the W. M. Keck Observatory in Hawaii, scientists realized Kepler-88 b and Kepler-88 c weren't alone. Their orbital variations are being influenced by an even bigger planet. Researchers shared their discovery this week in the Astrophysical Journal.
"At three times the mass of Jupiter, Kepler-88 d has likely been even more influential in the history of the Kepler-88 system than the so-called King, Kepler-88 c, which is only one Jupiter mass," lead researcher Lauren Weiss, postdoctoral fellow at the University of Hawaii Institute for Astronomy, said in a news release. "So maybe Kepler-88 d is the new supreme monarch of this planetary empire -- the empress."
Jupiter is sometimes referred to as the king of solar system, regarded so for its gravitational influence on the rest of the planetary bodies surrounding our sun. Its large mass is credited for Mars' small size and the presence of the asteroid belt. Some astronomers estimate Jupiter helped propel the comets that brought water to early Earth into the inner solar system many billions of years ago.
By studying the king's -- or empresses -- of other solar systems, scientists can gain a better understanding of how giant planets influence the evolution of planetary systems.