Why stars have been mysteriously disappearing 

The Mayans saw it as a forecast for the welfare of their homeland. The Greeks personified it with the myth of the Seven Sisters. The Chinese called them “guest stars.” 

And what is the modern world’s take on one of the oldest mysteries known to humankind? Put simply, we’re split between verifying the existence of aliens and continuing the never-ending search for a physical explanation behind why hundreds of massive stars have vanished in the past century. 

To explain why the astrophysics community has been pondering explanations for this phenomenon for so long, one needs to understand the life cycle of a star. According to researchers at NASA, all stars are born from clouds of dust and gas that spin, collect material, and heat up over time. Nuclear fusion in the star’s core releases energy throughout its lifetime. A star can die in two ways: it gradually loses its luminosity or becomes a supernova and leaves behind a dense neutron star. Or, in the case of a larger star, a black hole. 

But after looking through star maps and observation catalogs from the past hundred years, the Vanishing & Appearing Sources during a Century of Observations Project found that around one hundred stars have disappeared with no sign of the usual traces left behind by a slow death or supernova. While astrophysicists search for a concrete answer, several theories are debated among the scientific community. 

Many researchers agree that rather than vanishing, these stars are simply obscured. However, the astrophysics community is still debating what exactly is obscuring the vanishing stars. Some astrophysicists believe that the answer is supermassive black holes. Since they accumulate material like particles and dust, neighboring stars can disrupt this flow and become obscured in the process by outflowing blobs of plasma, gas, and dust. Other astrophysicists, branching from the topic of dust, theorize that dense clouds of dust particles are obscuring our view of the vanished stars, such as Tabby’s Star. But dust clouds pass along, and therefore only temporarily dim the light from the stars they obscure. On the other hand, the majority of the vanished stars in question have either been gone for too long or are steadily dimming.

There’s one more theory on what’s obscuring these stars, and it’s the first of several to stretch our knowledge of astrophysics: dark matter. Some researchers theorize that the massive vanished stars actually did die, but instead of exploding into supernovas before becoming black holes, the gravitational collapse at the center of these massive stars was so intense that they went straight into the black hole phase — this is called a failed supernova. However, the idea of failed supernovas goes against our fundamental understanding of every star’s life cycle, even though it is mathematically possible. 

In the 1960s, astrophysicist Nikolai Kardashev theorized that extraterrestrial civilizations have started generating energy directly from their stars. Later on, American theoretical physicist Freeman Dyson built onto this idea by modeling the Dyson sphere, a hypothetical sphere constructed around a star. This megastructure would not only take energy directly from the star but block out its light from onlookers. Even though this would theoretically deprive these extraterrestrials of light, proponents of Dyson and Kardashev’s theories argue that if they can build a Dyson sphere, these civilizations should also be technologically advanced enough to harness such energy from a star in another system. Astrophysicists have not detected the infrared signals that would be expected from such immense works of technology, so this theory has neither been proven nor disproven.

Even after thousands of years, the cause behind our disappearing stars is still an ongoing debate, as theories in astrophysics often lie within the gray space between being neither proven nor disproven. As researchers look further into deep space exploration and our technology improves, we can eventually find a definite answer. Until then, we’ll keep exploring theories and deciding for ourselves what is worth believing. 

“Even after thousands of years, the cause behind our disappearing stars is still an ongoing debate.”