Unlike our solar system, which consists of a single star, it is believed that about half of all star systems, such as GW Ori, where astronomers have observed the new phenomenon, consist of two or more starsgravitationally connected to each other.
But no planets orbiting three stars in a circular orbit have been discovered until now. At least not yet. But that seems to be changing.
Using the powerful Atacama Large Millimeter/submillimeter Array (ALMA) telescope, UNLV astronomers have analyzed three observed dust rings around three stars. Such rings are crucial for the formation of planets. In doing so, the scientists discovered a significant but mysterious "gap" in the triple dust disk.
The research team explored various origins, including the possibility that the gap was created by gravitational momentum from the three stars. But after building a comprehensive model of GW Ori, they concluded that a more likely and fascinating explanation for the space in the disk is the presence of one or more massive planets similar in nature to Jupiter.
Gas giants, according to Jeremy Smallwood, lead author and recent graduate student in astronomy at UNLV, are usually the first planets to form in a star system. They are followed by terrestrial planets such as Earth and Mars.
The planet itself cannot be seen, but the finding, reported in a September study in Monthly Notices of the Royal Astronomical Society, suggests that it is the first ever discovered planet with a triple orbit. In the coming months, scientists hope to get direct evidence of the phenomenon.
Illustration: ALMA (ESO/NAOJ/NRAO), ESO/Exeter/Kraus