In just half a century, more than 800 stars have disappeared mysteriously, and alien civilizations are building Dyson spheres?

If suddenly one day, the night sky is darkened, it will be a devastating thing for the universe. Because the stars we see are other stars in the universe.

In fact, some stars have really gone out. The European Aviation Agency compared the sky map taken by the United States now and 50 years ago and found that there are more than 800 stars "missing". What exactly happened to these stars?

Some people think that this may be the normal demise of stars, but some people think that this is the use of Dyson spheres.

What does the normal death of a star look like? What is a Dyson Sphere? What kind of alien civilization can use Dyson spheres? What if humans had Dyson spheres?

In just half a century, more than 800 stars disappeared mysteriously. Is it really an alien civilization building a Dyson sphere?

What does the normal death of a star look like?

Just as living things have their own lifespans, stars also have their own lifespans. In the world of stars, millions and tens of millions only start, and more than 100 million does not count. Take our sun, for example, which has a lifespan of about 10 billion years.

Generally speaking, the lifespan of a star is related to its mass. A star with a higher mass has a shorter lifespan, and a star with a smaller mass is likely to exist for tens of billions of years. The stars that can be seen by the naked eye in the night sky are not small in mass. However, the largest number in the universe are red dwarfs that are not very bright. In the Milky Way, about 70% of the stars are red dwarfs.

Stars of different masses have different stellar paths. They all go through a period called main sequence stars, which is when they are most stable and easiest to spot. Most of the stars in the night sky are main sequence stars. Main sequence stars are equivalent to the young adults of stars.

A star with a huge mass (greater than 8 solar masses) will expand violently after completing its main sequence star period and become a red supergiant. At this time, it is likely to swallow all the surrounding celestial bodies. When the expansion reaches the limit, a supernova explosion occurs, and the material on the surface is scattered in the universe to form a nebula; the core shrinks, and either a neutron star or a black hole is formed.

Smaller stars (less than or equal to 8 solar masses) will also expand after completing the main sequence star, but their volume is much larger than that of many red supergiants, and can only be called red giants. The red giant does not explode when it expands to its limit, but collapses from the inside out, leaving behind a denser core. The core is grayish-white, with a little residual energy giving it a faint cool white glow. At this time it was called a white dwarf.

In general, there are three endings of stars: white dwarfs, neutron stars and black holes. In the universe, almost every day, stars are dying, and stars are being born at the same time. The birth of stars comes from nebulae, and nebulae come from supernova explosions, which can be described as a cycle.

So, what is the suspected Dyson sphere?

What is a Dyson Sphere?

Dyson sphere is an artificial celestial object imagined by astronomers, originally proposed by physicist Freeman Dyson, hence the name.

The energy we use seems to be mined on the earth, but in fact their energy comes from the sun, such as the energy of fossil energy coal, oil, and natural gas, which is converted from ancient solar energy stored in ancient organisms. In fact, the solar energy received by the planets in the entire solar system only accounts for 1/10^9 of the total energy emitted by the sun, not to mention the solar energy that humans can use.

In order not to let the sun's energy be wasted in vain, physicist Dyson imagined an artificial celestial body that can wrap the entire sun, absorb the sun's energy, and convert it into human needs. The sun is a huge nuclear reactor, and the hydrogen atoms on it are undergoing nuclear fusion. Dyson spheres can use most of the sun's energy to support the development of civilization.

By analogy, as long as it is a star, it can be surrounded by a Dyson sphere, but the size of the Dyson sphere used is different. Because the Dyson sphere can use most of the energy emitted by the star, the star emits less light, and its surroundings begin to fall into darkness, and humans can no longer observe the star. From Earth's point of view, these stars are bizarre disappearances.

Some would argue, what if a black hole devoured these stars? Or, perhaps, these stars have reached the end of their lifespan, leaving their main-sequence period and declining in brightness. These are theoretically possible, but half a century is not worth mentioning for the universe at all. These stars are at the end of their lifespan, and it is coincidence's mother who opened the door for coincidence - coincidence is home.

And there is one point that we cannot ignore, that is, many stars in the night sky seem to be very close, but in fact, the distance between them is hundreds or thousands of light-years. Therefore, it is impossible for these 800-plus stars to be swallowed by the same black hole. It's just too good for non-interfering stars to be swallowed by different black holes at about the same time.

Therefore, some people think that an alien civilization is using Dyson spheres. So, what level does an alien civilization have to reach to create a Dyson sphere?

What level of civilization is using the Dyson sphere?

The theory of the Dyson sphere was born in 1960, and until 2022, humans cannot even create the prototype of the Dyson sphere. Because at the current level of human civilization, Dyson sphere is still too far away for us.

According to the astronomical classification standards for civilization levels, we humans have not even reached the primary civilization. First-level civilization, also known as planetary civilization, if human civilization enters this level, then we can use the energy of the entire earth. For example, the core of the earth, the temperature of the core is 4000 to 6000 degrees Celsius, and the heat alone is beyond human expectations. In front of the energy of the earth's core, the little bit of energy in the earth's crust is not comparable at all.

It sounds like the first-level civilization is already very powerful, but it still cannot create a Dyson sphere. The civilization level that can use the Dyson sphere must reach at least the second level, which is the stellar civilization. If human beings reach the second level of civilization, the energy of the entire solar system will be used by us, and at this time, a Dyson sphere is needed to cover the sun.

When the third-level civilization is reached, that is, the galactic civilization, humans can put the Dyson sphere on any star in the Milky Way; when the fourth-level civilization is reached, the Dyson sphere will spread throughout the universe. Therefore, a Dyson sphere that can eclipse more than 800 stars must be a civilization of level 3 or above.

If human beings encounter this alien civilization, in front of them, human beings will be as small as an ant. Humans have not even reached the initial level of cosmic civilization. Astronomers say that human civilization can only rank 0.7 in the universe. In the face of civilizations above the third level, this gap even exceeds that between us and animals. Perhaps how humans treated animals in the first place, this civilization will treat us.

But don’t be too pessimistic. A civilization that can build a Dyson sphere may not necessarily see this energy of the solar system.

Will humans have a Dyson sphere in the future?

It is indeed very difficult for humans to make a Dyson sphere today. It is not like artificial satellites and space stations. First of all, its volume needs to be larger than the sun, so that it can wrap the sun and absorb energy. The volume of the sun is 1.3 million times that of the earth, and human beings cannot even create an artificial celestial body the size of the earth.

Theoretical physicist Michio Kaku once predicted that it will take human beings 100 to 200 years to reach the primary civilization, and 1000 to 2000 years to reach the secondary civilization. From the second-level civilization to the third-level civilization, it takes 100,000 to 150,000 years in the middle. Waiting for humans to make more than 800 stars disappear mysteriously, at least wait for more than 100,000 years.

If mankind develops at the current rate, it is possible to have a Dyson sphere. In addition, on the basis of Dyson spheres, Dyson clouds, Dyson shells and Dyson bubbles can also be made, and different forms are suitable for different types of stars. When human beings can reach the fourth-level civilization, then the entire universe will be artificial celestial bodies of the Dyson series.

With the energy provided by these stars, human beings may also move towards higher civilizations. When they reach the fifth-level civilization, they will have the ability to create, and we can create "earth" and "sun".