This Giant Exoplanet Strangely Orbits Around Its Star

A new planet with unique characteristics and strange behaviors than ever has been recently discovered by astronomers. Named HR 5183b, the exoplanet is three times more massive than Jupiter, and its orbit particularly shaped like an egg. Although many other gigantic elliptical planets have been found, they all feature the close proximity to their stars. Scientists have explained such discovery in a paper that will be published in The Astronomical Journal in the coming time.

The method in which scientists use to detect the planet is through radial velocity. This procedure makes use of the swaying motion of the parent stars obtained by the gravitational force of the planets that orbit the star. According to scientists, the collecting data process over the duration of the orbital periods is not easy, as it takes years, such as Neptune with 165 years. For HR 5183b, researchers have yet acquired sufficient data about its orbital period although they have been continuously observing it for more than 20 years. It is estimated to take 45 to 100 years for the planet to complete its orbit movement. More interestingly, the planet was discovered not because of its orbital period but for its peculiar movement.

The California Planet Search is considered to be one of the few organizations that have been able to observe planets for decades. This is critically important for the recognition of exoplanets with long orbital duration through radial velocity. To detect this mysterious planet, scientists had to research the data of three separate observatories. As clarified by the Head of The California Planet Search, Andrew W. Howard, this planet tends to wander along its off-center orbit to the direction of the star HR 5183’s planetary system. It also accelerates gradually while coming closer to the star.

As such, scientists recognized that the planet moved further from the star after approaching it. Also according to the cosmo principles, new planets often have flat and circular orbits due to the formation of material disks left behind after a star’s formation. As for HR 5183, the reason for its eccentric orbit is largely due to the possibility of gravitational external force caused by celestial bodies. Scientists have speculated that there was once a planet with similar size located near HR 5183. And when the two planets have enough distance, they would force each other away, leading to the extreme eccentric orbit of HR 5183b.