(CNN) – A giant star near the center of our Milky Way galaxy is flashing like a stellar beacon, according to new observations by astronomers. The star is more than 25,000 light-years away from Earth.
The star known as VVV-WIT-08 was so faint that it nearly disappeared from view while astronomers were observing.
It is not uncommon for a star’s brightness factor to change. Some stars pulsate, or another star can be obscured within a stellar pair, called a binary. But it is extremely rare for a star to fade and shine again, that is, to flicker.
Observations of this star led to the belief that it might belong to a new class: a “shining giant” binary star system. This category includes giant stars hundreds of times larger than our Sun that are dwarfed every few decades by an unseen companion, which may be another planet or star.
This companion is likely surrounded by a disk of matter that hides the giant star, causing the flickering pattern that astronomers have observed.
The study was published Friday in the newsletter. Monthly Notices of the Royal Astronomical Society.
The center of our galaxy is a dense region containing a supermassive black hole, giant star clusters, gas streams, and magnetic filaments.
It’s a statement, said Sergei Koposov, co-author of the study and professor of observational astronomy at the University of Edinburgh.
At first, researchers speculated that an unknown dark object could pass in front of the giant star, but this would only be possible if there were a large number of such objects in the galaxy, which is unlikely.
Studying other unique star systems, such as the brightness and radiance of giant stars, or the display of this flashing pattern, helped researchers determine that there may be a new class of flashing giant stars that needs to be investigated. So far, there seem to be about six such systems.
The star system in this study was found using the “VISTA Variables in the Via Lactea” or VVV survey. This project, which uses the VISTA telescope from the European Southern Observatory in Chile, has observed a billion stars for nearly a decade to see how their brightness changes.
It’s a statement, explained Philip Lucas, VISTA Project Leader and Professor at the University of Hertfordshire. We don’t really know how these flashing giants came about. It is exciting to see the discoveries of VVV after many years of planning and data collection.
The star’s dimming was also observed using the Optical Gravitational Lens Experiment, known as OGLE, a study of the sky led by the University of Warsaw. Data sets from both studies showed that the star darkens equally in infrared and visible light.
Astronomers will continue to search for more giant flashing star systems to learn more about them.
Lee Smith, discovery leader and research associate at the University of Cambridge’s Institute of Astronomy, said in a statement. “By doing this, we can learn something new about how these types of systems evolve.”