Thousands of Stars Disappeared, Why? | Space Mysteries

When you think of mysterious phenomena, you might conjure up thoughts of eerie ghost stories or tales of cryptids lurking in the darkness. But, to find some of the most truly perplexing mysteries of the unexplained, you only need to turn your eyes to the stars. The universe has existed for around 13.8 billion years and holds some of the greatest mysteries that continue to baffle astronomers to this day. The human imagination can run wild, dreaming about what strange and otherworldly phenomena might be out there in the vast expanse of space. But, what happens when you don't just imagine something, but witness it with your own eyes? In Southern California during the year 1950, astronomers at the Palomar Observatory near San Diego documented something strange. Their telescope was pointed at a patch of sky one night, taking pictures of the cosmos every couple of minutes. After all the pictures were developed, astronomers took a closer look at two of them that were at the same patch of sky, taken 30 minutes apart from each other. When they had a closer look, they noticed that the second picture had less stars than the first one. In fact, there were nine stars that showed up in the first picture that did not show up in the second one. How could nine stars disappear in the span of 30 minutes? Our night sky today is drastically different from the one we saw 10 years ago. The brilliancy of stars is slowly diminishing until their vibrant glow vanishes in sight. When this anomaly of disappearing stars was first documented, no one seemed too concerned about the disappearance. It wasn't until decades later that this information was looked at closely and understanding these disappearances became the focus of a number of astronomers. If in this instant the sun just disappeared, what would happen? Well, we would not know anything about that fact for eight minutes and 20 seconds. We would still orbit the sun, we would still feel its sunlight, because the sun is eight minutes and 20 light seconds away from us. So the moment you remove the sun, there's the light still coming our way. And then eight minutes and 20 seconds later, we plunge into depths of cold. One of the first theories that was put forth to explain the disappearances claimed that the defects in the telescopes were to blame for this anomaly. While this could have been the case, this theory was quickly ruled out upon further investigation of the instruments that gathered the data. Seventy years after the first disappearing stars were documented by astronomers, one scientist was so intrigued by this cosmic mystery that she decided to dedicate her career to trying to shine light on this problem and understand what was really happening. Dr. Beatrice Villarroel from the Nordic Institute for Theoretical Physics is leading the team to try and find the answer to this mystery that has remained unsolved for the past 50 years. She heads the team in charge of the vanishing and appearing sources during a century of observations, which is also known as VASCO. This team works the data gathered during the last few decades from instruments all around the world with a mission to find stellar objects that have disappeared over time. This project has flagged over 250,000 objects that have potentially gone missing. Once this data came back to the VASCO team, they combed through this data and were able to discover the reason the object disappeared for the vast majority of the potential missing ones. But there are still many objects that have disappeared without any concrete reason that astronomers can figure out. These disappearances could be the result of an afterglow effect following gamma-ray bursts or fast radio bursts known as FRBs. While scientists do not have a complete understanding of what creates these gamma-ray bursts and FRBs, they know enough to posit this theory. If a telescope was taking snapshots of the cosmos just after there was a large gamma-ray burst, it may pick up that burst as a bright spot in the sky. But when another snapshot in the same location is taken without the gamma-ray burst, that bright spot will be gone. When scientists look through these snapshots, it may appear like a star that was in the original photograph had disappeared from the sky. But while this theory does make sense and can explain the disappearance of some stars, there is no evidence that this is what caused them. Could these stars just be moving in between the two photographs being taken? While many stars are moving through space, they move at a pace that astronomers can usually follow. Stars do not make big movements throughout the sky. This theory may be correct for some of these objects, but there are objects that astronomers know could not have moved in the time between the recordings. So, there must be something else causing the disappearances as well. Astronomers know that as stars age, the amount of light that they produce will vary. This change is thought to only happen very slowly over thousands, if not millions of years. If a star's luminosity changes dramatically after it has already been photographed by a telescope, the next time that telescope scans its location, it may not be bright enough for the telescope to record it. But, astronomers know that they do not have a complete understanding of the universe. If this is the case and the stars are not disappearing, only rapidly changing in their luminosity, then astronomers have more to learn about the nature of stars. Most of us know that when a massive star reaches the end of its life, a giant explosion known as a supernova takes place. The star explodes into one of the largest, violentest events in our universe, spewing out its mass into space. After the explosion takes place, the matter that used to make up the star's core begins to collapse in on itself, forming a ball. This ball becomes denser and denser, pulling in more and more matter as a new black hole is born. This is basically how astronomers understand the events leading to the birth of a black hole. But, there may be a way that certain black holes can be born from stars while skipping a major step in the process. The Star Never Goes Supernova Astronomers now believe that between 10 to 30% of black holes are created without a supernova. This happens when a star that is roughly 20 solar masses reaches the end of its life. But, instead of exploding, these stars begin to collapse in on themselves, first creating a gravitational pull strong enough to overpower the outer force, trying to explode. This results in the star becoming a black hole without ever going supernova. It can be very difficult to detect new black holes, and finding the remnants of a supernova is one way that astronomers have helped detect new ones in the past. These events are not nearly as common as typical supernovas, but astronomers believe that in the Milky Way alone, one star collapses to a black hole without going supernova every 300 years or so. One of the more fascinating theories to explain the disappearance of stars has to do with alien civilizations. This is not a far-out-there theory either. Even VASCO works in conjunction with SETI, the Search for Extraterrestrial Intelligence, in several areas and includes the possible interference by alien race in its reports regarding these disappearances. The lack of explanation for this mystery has led to some of these theories. There are a number of roles that extraterrestrials have been theorized to have played in this. One of the more enthralling theories has to do with a theoretical megastructure called a Dyson Sphere. Dyson spheres are giant machines that are built to encompass a star and harvest a large portion of the star's energy output. A civilization advanced enough could have built structures such as this and are extracting the energy from the star and leaving behind the empty space that we are seeing now. Other theories as to what roles an alien civilization may have played in this include the construction of other massive structures that block a star's light from reaching us, to the civilization removing a star by extinguishing it for a reason we may never know. Whether these stars actually disappeared or are just blocked from our view, or were never really stars to begin with, astronomers are going to continue to hunt for the answer. This is another of the great mysteries that science has uncovered while exploring the universe that we all live in, and as long as there are mysteries, there will be people ready to take up the challenge to solve them. Is there a cosmic mystery that you want to know the answer to? If you watched all the way to the end, we want to say thank you for watching and if you enjoyed this video, please feel free to hit the like and subscribe buttons so you won't miss any of our future videos.