This groundbreaking study observed a cloud of debris sharing an orbit with another planet, which could either be the building blocks of a new planet or remnants of a pre-existing one.
The outer world is not so out of reach anymore. After discoveries like Mars could have life, astronomers have found evidence of two planets orbiting around the same celestial body, as reported by BBC Sky at Night Magazine. In the new study, a cloud of debris was seen sharing the orbit of another planet. This debris could be building blocks of a new planet or be part of a planet that had already been in existence. At present, astronomers make only detection, but if the finding is comprehensively proven, then for the first time, a sibling of a planet would be seen to be orbiting the same star.
The discovery is essential as it aids in further proving the existence of Trojan Planets. Trojan Planets are defined as worlds that share both the same orbit as well as stars. The Solar System in which Earth resides also has a similar example. It has happened with respect to the Trojan asteroids of Jupiter. Trojan asteroids are more than 12000 rocky bodies, sharing the orbit of Jupiter around the sun. Despite assumptions, it has been a challenging task to prove Trojan Planet's existence in any galaxy.
Astronomers have detected what may be two planets forming in the same orbit. https://t.co/fD9Y7JwK8I— News from Science (@NewsfromScience) July 19, 2023
Moreover, the recent discovery was made by a team of astronomers with the aid of the Atacama Large Millimeter/submillimeter Array (ALMA) in the Atacama Desert of Chile. The astronomers were observing the PDS 70 system, which is a star 400 lightyears away. They are also known to be the host of two planets which are Jupiter-like in nature. The discovery occurred when they spotted a cloud of debris at a location where Trojans were believed to be found.
They conducted their investigation at the Lagrangian zones. These zones are the places where the gravitational equilibrium present between the planet and the host star can trap any kind of cosmic material. It was present around PDS 70's orbit. On further observation, they found that the mass of the debris was almost twice in comparison to the moon.
Olga Balsalobre-Ruza, a student at the Centre for Astrobiology in Madrid, Spain, shared about the discovery, "Who could imagine two worlds that share the duration of the year and the habitability conditions? Our work is the first evidence that this kind of world could exist." She further added, "We can imagine that a planet can share its orbit with thousands of asteroids as in the case of Jupiter, but it is mind-blowing to me that planets could share the same orbit."
Nuria Huélamo, a senior researcher at the Centre for Astrobiology, regarding the research she said, "Our research is a first step to look for co-orbital planets very early in their formation." Itziar De Gregorio-Monsalvo, ESO Head of the Office for Science in Chile, who was also a contributor to the research, gave the statement, "It opens up new questions on the formation of Trojans, how they evolve and how frequent they are in different planetary systems." The next step for the team is to wait till 2026. During that time, the PDS 70b and its 'sibling' cloud of debris will orbit together around the star.