Researchers discover a stable planet in a triple-star system
A team of researchers working at the Harvard-Smithsonian Center for Astrophysics has announced the discovery of an exoplanet in a stable orbit around a star, occupying a triple star system.
The detailed study of the discovery of distant world, known as KELT-4Ab was published in the Astronomical Journal.
While the planet orbits one star in the system, that star is circled by a pair of stars. Standing on the surface of the KELT-4Ab, the two orbiting stars would appear as bright as the full moon does in our sky. In addition to describing an exotic solar system, the study also provides new details on the evolution of a “hot Jupiter,” or a gas giant that orbits close to its host star. However, it has a quite rare multi-star system at a distance of around 700 light-years from our planet.
The KELT-4 system came to be known just sometime back, it’s just recently that astronomers have realized their triple-star nature. The system has a main bright star known as KELT-4A and a binary pair of stars known as KELT-4B and KELT-4C jointly called KELT-4BC.
As per the research paper published by the study team, “The objects under study in the new system are KELT-4Ab, a gas giant planet, similar in size to Jupiter-it takes approximately three days to make its way around the star KELT-A, which serves as its sun. The other two stars, named KELT-B and C, are much farther away and orbit one another over the course of approximately 30 years. It takes the pair approximately four thousand years to orbit KELT-A. The researchers suggest that the view from KELT-4Ab would likely be one where its sun, KELT-A, would appear roughly forty times as big as our sun does to us due to its close proximity. The two other orbiting stars, on the other hand, would appear much dimmer due to their great distance, shining no brighter than our moon.”
Space scientists have known of the existence of the KELT system prior to this study, but it was thought that the binary stars were actually just one star. The researchers on this new effort were able to see that they were actually a binary system courtesy of two robotically controlled telescopes on two different continents-one is in Arizona, the other in South Africa. Together they are known as the Kilodegree Extremely Little Telescope (KELT), which is of course how the KELT system got its name.
The transiting exoplanet dubbed asKELT-4Ab have been found around KELT-4A by the astronomers. In comparison, KELT-4Ab is a world almost 50% bigger than Jupiter.
KELT-4Ab moves around its host star in just three days, which makes it a ‘hot-Jupiter’. It is quite close to KELT-4A due to which the exoplanet’s atmosphere has dramatically inflated.
The planet’s discoverers said that its host star is the brightest host of any inflated hot-Jupiter found so far, thus it may prove to be a priceless astronomical target for more studies regarding the nature of such extreme worlds.
“Newly-discovered planet KELT-4Ab has three suns-but that triple-solar view isn’t the only weird thing you’d see happen overhead. Not by a long shot,” according to a news report published by Gizmodo.
According to a report in Outer Places by Janey Tracey, “Astronomers have just found a planet with an even cooler sunset than Tatooine. Researchers at the Harvard-Smithsonian Center for Astrophysics have reported the discovery of KELT-4Ab, an “inflated Hot Jupiter” that stably orbits the brightest member of a three-star system.”
The revelation that the system actually has three stars rather than two makes KELT-4Ab only the fourth known planet to orbit within a three-star system, or a “hierarchical triple.” This is also the closest triple-star system to Earth yet, with an unusually bright main star that will make the system very valuable for observation.
You can read the team’s full report in The Astronomical Journal.