In 2004, scientists using the GALEX space telescope discovered an unusual nebula, visible only in the ultraviolet range. And only recently have astronomers figured out how it formed.
In the nebula, TYC 2597-735-1 is the central star, surrounded by an extraordinary ultraviolet ring, which was discovered with the NASAGalaxy Evolution Explorer telescope (GALEX).
It is noted that the star TYC 2597-735-1 itself turned out to be old, thermonuclear reactions of hydrogen in its interior has already ended. Despite this, around it, there is an accretion disk of matter falling onto the surface – as is typical for young stars.
Most of the stars in the Milky Way are in binary systems. These are pairs of stars that revolve around each other. If they are close enough to each other, then the stars merge and one engulfs the other. When a satellite loses its orbital energy, it can eject energy at high speed.
Scientists have suggested that this is how the nebula formed. To test this hypothesis, the team observed the nebula with two different spectrographs on large telescopes. And the theory was confirmed: the Blue Ring Nebula was formed by the remnants of the merger of two stars that occurred five thousand years ago. As a rule, such objects quickly disappear from view behind dense clouds of gas, but the unique features of this nebula allow you to see even the central star.