Astronomers have once again discovered a surprising phenomenon in the depths of space. A dying star called V Hydrae, in its death throes, has released rings and streams of peculiarly shaped matter into the surrounding space, the first such observation in the history of astronomy.
Star V Hya is located about 1300 light-years away in the constellation Hydra. It appears to be a carbon-rich, gigantic red star in the final stages of its life cycle. This star will gradually shed its outer shell before it explodes, becoming a white dwarf surrounded by a gas-dust nebula.
However, the star V Hya is moving towards its final phase in a rather unusual way. Looking at the star with the ALMA radio telescope, astronomers saw that instead of dumping its upper layers of matter in all directions, like all other such stars, V Hya has launched a series of rings into its surroundings. Astronomers have even managed to count the number of these rings, which is six, and all these rings have been released within the last 2,100 years, a negligible amount of time by cosmic standards. All the rings have formed a kind of deformed disk around the star V Hya, which astronomers have given the dubious name DUDE (Disk Undergoing Dynamical Expansion).
In addition to the rings, astronomers have observed huge clouds of matter ejected into space by the star, almost perpendicular to the plane of the rings. These clouds, which are shaped like an hourglass, are expanding in space at a speed of 864,000 km/h.
Even before the discovery of the rings and hourglass-shaped matter streams, V Hya was a very special star, different from other stars. Every eight and a half years, this star sent plasma spheres the size of Mars into space. Astronomers have tried to explain this bizarre behaviour by the presence of a companion star, a neutron star or white dwarf, in V Hya. If the companion orbited V Hya every 8.5 years and periodically touched the upper layers of its swollen atmosphere, it would capture some matter and shoot it into space.
All of the features mentioned above make the star V Hya a totally unique cosmic object, the study of which could give astronomers a lot of new knowledge about the life and death periods of stars of a similar class.
"The end-of-life period of a star, when they make the transition from red giant to white dwarf, is a rather complex process that has not yet been fully understood," says Mark Morris, lead researcher, "The discovery that during this process stars can produce rings and jets of matter spreading at enormous speed has given us a wealth of new information that has gone into the overall store of knowledge."