Solar system with three super earths discovered

A new planetary system discovered by researchers at the University of Geneva (UNIGE) is home to four planets, including one giant outer world and three super-Earths– and it’s fairly close at a distance of only 21 light years from Earth.

The study authors, who report their discovery in the journal Astronomy & Astrophysics, said that one of the planets is likely a volcanic world made out of molten rock, and that the planet with the shortest orbit has been spotted transiting across the face of its star, HD219134.

According to Discovery News, the four-planet system is located in the Cassiopeia, an M-shaped constellation found in the northern hemisphere. Measurements conducted from both ground and space telescopes showed that the transiting planet is 1.6 times larger and 4.5 times more massive than Earth, and that it has a similar mean density and likely a similar composition as well.

Proximity of system makes it conducive for future studies

The temperature of the planet with the shortest orbit, HD219134b is approximately 700 degrees Kelvin (800 Fahrenheit), the authors said, meaning the planet is not in the habitable zone of its star. However, it is the closest transiting planet discovered by scientists thus far, giving them the opportunity to further study its atmosphere and composition, the authors told the website.

The UNIGE team also discovered three other, longer-period planets in the system – one which weighs 2.7 times the Earth and orbits HD219134 once every 6.8 days and a planet weighting 2.7 times as much as our home world that has an orbital period of 46.8 days. Both of these planets are located in the inner regions of the system, the researchers explained in a statement.

The fourth planet is a small-Saturn type world that orbits the star once every three years or so, they added. The researchers believe that the proximity and brightness of this Solar System will make it favorable for a detailed analysis of the physical properties of the planets, especially since it is similar to our own Solar System in that it has small inner planets and a larger outer one.

“For atmospheric studies, astronomers are already planning observations with ground-based high-resolution spectrographs and the future NASA-ESA James Webb Space telescope (JWST) using transmission spectroscopy techniques,” they said. “They even dream about direct imaging of the outer planet in the system with the new generation of giant telescopes on the ground.”

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Image credit: NASA JPL/Caltech