On October 29, 2020, the MROZ Astronomer Prosstron of the University of Warsaw, along with an international team of scientists, made a groundbreaking discovery. They successfully detected a faint light signal from the center of our Galaxy, initially appearing unremarkable. This signal, named OGLE-2016-BLG-1928, turned out to be the first confirmed sighting of a planet comparable in size to Earth, yet not tethered to any star. These planets, known as wandering planets, roam freely in the space between stars, a concept that was previously only theoretical.
For Mroza, this achievement represented the realization of a lifelong dream. The thrill of uncovering something truly novel is unparalleled, he expressed, emphasizing that these moments are what drive his passion for scientific exploration. The discovery of the wandering planet exceeded his expectations.
While various projects over the past decade have hinted at the presence of massive Jupiter-sized planets wandering in space, the identification of OGLE-2016-BLG-1928 marks the first time Earth-sized planets have been observed in such conditions. In 2020, a different team involved in the Moa project also located a similar planet, MOA-9Y-5919. These findings suggest a previously unknown category of celestial bodies, with wandering planets likely constituting a significant portion of objects in our galaxy.
The discovery implies that a considerable number of these free-floating planets could exist in the Milky Way. Estimates suggest that each star might have around seven such planets associated with it. This revelation leads to the astonishing conclusion that trillions of wandering planets may populate our galaxy. This revelation is particularly awe-inspiring considering the recent realization of their existence. It is possible that the number of wandering planets even surpasses that of “normal” planets like Earth, which orbit stars, underscoring the exceptional nature of our familiar celestial bodies.