Ghost stars are arranged in strange patterns in our galaxy. Thanks to new research, scientists were able to understand why this happened. Ten years ago, astronomers recorded an unusual arrangement of planetary nebulae. Planetary nebulae are clouds of gas emitted by stars as they reach the end of their lives. Our star, the Sun, will do the same in about 5 billion years. These ejected clouds are like ghosts of dying stars. What’s strange is that such ghost stars are arranged in strange shapes with familiar shapes, for example the shape of an hourglass or a butterfly.

Astronomers have studied numerous planetary nebulae located near the center of the Milky Way galaxy. Although these nebulae are unrelated and come from different stars at different times, many of the shapes they form are similar. A new study published in Astrophysical Journal Letters confirms that this unusual nebula array actually exists. They also found that such alignments occur when these “ghosts” have companion stars nearby.

In fact, certain groups of stars, so-called close binaries, are responsible for this behavior. These are a pair of stars connected by gravity, whose components can exchange mass at certain stages of development. In this case, the companion star at the center of the planetary nebula orbits the host star in a very narrow orbit, smaller than Mercury’s orbit around the Sun. Without such a companion star, the nebulae would not be able to line up in mysterious lines. Scientists speculate that the final alignment was due to the initial separation of the binary components during the star’s birth.

For the study, astronomers examined 136 identified planetary nebulae in the Milky Way’s thickest part, the galactic bulge. They used the European Southern Observatory’s Very Large Telescope and then used data from the Hubble Space Telescope to study his other 40 nebulae. This discovery brings astronomers closer to understanding the reason for this mysterious arrangement. Star formation in the bulge of our galaxy is a complex process involving a variety of factors, including gravity, turbulence, and magnetic fields.

Until now, scientists had no evidence of what mechanisms could trigger this process and cause the formation of such coordinated lines. We now know that this arrangement occurs in a very specific subset of planetary nebulae. Such nebulae can be caused by the rapid motion of a companion star in its orbit. And the nebula’s oddly arranged arrangement could mean that the system is made up of closely packed binary stars whose orbits are primarily in the same plane.

The described research provides evidence that there are constant, controlled processes that influence star formation over billions of years and over vast distances. However, further studies are required to fully understand the mechanisms underlying the alignment.