Astronomers may have spotted never-before-seen mysterious star made of dark matter

Future observations of the star can help review scenarios of finding cosmic objects made of dark matter

A strange star system observed by the European Space Agency’s Gaia satellite might be a never-before-seen stellar object made of invisible dark matter, new research suggested.

The yet-to-be peer-reviewed study, posted as a preprint in arXiv, assessed data from the Gaia satellite on a cosmic system that consists of a Sun-like star and a much more massive stellar companion about 11 times the solar mass.

These objects are orbiting each other at a distance of 1.4 astronomical units – or about the distance at which Mars orbits the Sun – say researchers, including those from the Czech Academy of Sciences.

Previous research predicted the system consisted of a star orbiting a black hole.

While the likely explanation for the central object could be a black hole, the orbital mechanics of the system is also explained if the central dark object is a stable clump of bosonic, or “dark matter” particles.

Dark matter is an invisible material that is thought to make up most of the observable matter in the Universe.

Most models suggest dark matter is distributed evenly across the Universe, but some say it could also clump up.

In one such model, dark matter is theorised to be a new kind of boson, which are particles that carry energy and forces across the universe such as the widely known photon.

Some, yet undiscovered bosons, scientists have hypothesised, could have the ability to form large clumps, and a section of these could theoretically be the size of an entire star, they say.

Such a hypothetical cosmic object, known as a boson star – would be entirely invisible as these boson particles do not interact with light but can be identified via their gravitational influence on their surroundings, researchers say.

The new study suggests that the Gaia satellite observation data could be explained by replacing the central object with a boson star.

“Identifying the central dark object with a black hole is plausible, but rather challenging to support within the context of binary evolution given the characteristics of the binary system,” researchers noted, adding that a boson star instead can explain the observations for a “fairly reasonable” choice of parameters.

While researchers still point out that it is unlikely to be a boson star, they call for follow-up observations.

More simulations of these cosmic objects with further data, assuming one of them is a boson star, can reveal if dark matter is really part of this system.

“Future astrometric observations will further offer the possibility to distinguish amongst different boson star scenarios,” scientists wrote in the study.