Astronomers from the University of Tokyo and the University of Niigata in Japan have published a study in The Astrophysical Journal describing a potential new class of interstellar objects.
In their study, astronomers Takashi Onaka, Itsuki Sakon, and Takashi Shimonishi describe two “peculiar icy objects” in interstellar space, Phys.org reports. The molecular emission lines of the mysterious objects were captured using the ALMA telescope in Chile.
Traces of these objects were first noticed back in 2021, when researchers were studying data from the Japanese infrared space telescope AKARI. The two described objects are covered in ice, which consists of water and organic molecules. It was the potential presence of organic matter that attracted the attention of scientists. It is believed that ice plays a key role in the origin of organic molecules.
In the new study, astronomers focused on the infrared spectrum of the two objects, expecting to see traces of molecular emissions associated with the formation of stars. Instead, they found molecular emissions of silicon oxide and carbon monoxide, which, moreover, turned out to be more compact than similar emissions observed in other icy space bodies.
The obtained data were used to determine the chemical composition of the mysterious icy objects, as well as their size, trajectory of movement and distance from Earth. It turned out that the objects are located at a distance of approximately 30,000 to 40,000 light years from our planet.
One of them is moving much faster than the other. This suggests that the objects are not directly connected to each other. Analysis of the chemical composition showed that the ratio of silicon oxide to carbon monoxide in these objects is higher than in other icy bodies known to science.
The researchers believe that the objects they described are unlike any other object known to science, making them candidates for being a fundamentally new type of interstellar object.