Kepler-432b, a behemoth exoplanet, almost six times the size of Jupiter has been discovered by astronomers. The newly-discovered extra-solar world is located 2,850 light-years beyond Earth, orbiting around the red giant star, Kepler-432, in the Cygnus constellation. According to astronomers, this is an astounding discovery, it is one of the most dense and most massive exoplanets ever to be discovered.
Kepler 432-b has a mass 5.84 times that of Jupiter, the largest planet in the Solar System. Moreover, it revolves around its host star, Kepler-432, in just 52 Earth days. Therefore, the surface gravity has an immense force, inarguably too strong for it to be a habitable planet. Astronomers state that the shape and size of its orbit is unusual for the planet, considering it revolves so fast and so close to its parent star. Dr. Davide Gandolfi, an astronomer from the University of Heidelberg, stated nearly all known planets have a large, circular orbit. However, Kepler-432-b has a highly elongated orbit, an orbit that pulls the planet very close to star and then very far away from it.
The star, Kepler-432 is considered a red giant because it has already exhausted its core hydrogen and helium supply and is continuously expanding. According to Gandolfi, its radius is now four times that of the Sun and will gradually swell to an even larger size. As with any dying star, it will eventually swallow up its orbiting planets, including Kepler-432b, leading to an intense, fiery cosmic end to one of just a few extrasolar systems discovered by astronomers, to date.
As previously stated, the orbit of the planets brings it incredibly close and far away from the star, thus altering surface temperature by hundreds of degrees during its seasons. Dr. Sabine Reffert, a researcher on Gandolfi’s team, explained that throughout the winter season, the surface temperature on Kepler-432b is around 500 degrees Celsius, increasing to a scorching 1,000 degrees Celsius during the short summer season. Such an extreme fluctuation in temperature means surface rock would constantly melt and harden, altering the topography of the planet’s surface.
Since the star has already begun to swell, Kepler-432 will only live for another 200 million years, an exceptionally short time on the cosmic scale. Previously, astronomers have only located five exoplanets that orbit their red giant hosts stars as close as Kepler-432b does. By using spectroscopic measurements of their planetary transits, astronomers confirmed the surface geographic and atmospheric characteristics are comparable to Mercury, one of the most violent worlds in the Solar System.
To make the astounding discovery, the group of astronomers utilized the highly-sophisticated 2.2 meter telescope at Calar Alto Observatory, in Spain. Gandolfi explained the discovery of the exoplanet was due to the outstanding support and scheduling opportunities from the staff at the observatory. He said the observatory has been working for years to locate and analyze exoplanets and their possibly life-harboring characteristics. Even though Kepler-432b is far from what astrobiologists would call habitable, the astronomers who made the discovery still believe it was an astonishing revelation.
By: Alex Lemieux
Picture: Bill Lile – Flickr License