Three Super-Earths Found Orbiting Nearby Star

That planet which was called HD 219134b is almost 5 times heavier than the Earth and more than 1.5 times larger.

The finding was enabled by the HARPS-N spectrograph which is located with the Italian Telescopio Nazionale Galileo in the Roque de los Muchachos Observatory.

The planet has a density similar to the Earth’s.

But HD219134b is exciting for another reason: it is the closest transiting planet known to scientists, and thus offers a rare opportunity for further study of its composition and atmosphere against the backdrop of its star.

The planet, likely a volcanic world of molten rock, resides in a system with two other super-Earths orbiting a bright, dwarf star. Fortune favors the courageous; HD 219134b does indeed transit the star.

Just over a week after the discovery of an Earth-like planet dubbed “Earth 2.0”, astronomers have now discovered what appears to be three super-Earths surrounding a distant dwarf star.

The scientists hope that by training more telescope, the will know more about the planet and its atmosphere, if ever it has one.

Super-Earths have a mass higher than Earth’s but are lighter than gas giants like Neptune, Saturn or Jupiter.

As for the other rocky world discovered in this system, scientists say they have an orbit of 6.8 days and 46.8 days, respectively. It is so bright that it’s visible to the naked eye. If, by chance, these 2 planets would be in a coplanar configuration with their 3rd inner sister, as often observed for compact systems, the whole family might be transiting.

According to team member Prof Stéphane Udry from the University of Geneva in Switzerland, ESA’s CHEOPS satellite will provide the flawless tool for future observations to capture the potential transits.

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.

This system, reminiscent of our own solar system with the inner “small” planets and the outer gaseous one, will without doubt encounter a growing interest from the astronomical community. “Indeed, the proximity and brightness of the star makes the system the most favourable one for an in-depth characterisation of the planet physical properties”, said the astronomers. They even dream about direct imaging of the outer planet in the system with the new generation of giant telescopes on the ground, the extremely large telescopes, planned for the next decade.