Most blue supergiants are massive stars formed by the contraction of larger nebulae. A small number www.biquge.info of blue supergiants are formed by the surface temperature of red supergiants rising by external influences (such as collisions).

In fact, the star Cygnus P is a high-luminosis blue variable star, so it is also classified as a supergiant.

Similarly:

Betelgeuse: Located about 863 light-years from Earth, in the lower right corner of the constellation Orion, with a radius of 77 times that of the Sun and a total luminosity of 110,000 times that of the Sun, it is 863 light-years from Earth.

Seamount II: Inside the Keyhole Nebula NGC3372, located at the base of the ship in the southern sky. It is not far from the solar system and the Sunrise galaxy (6000-7500 light-years). Seamount II is very large, with a mass of about 120-150 times that of the Sun and a luminosity of 400-5 million times that of the Sun. Activity is extremely erratic, with frequent outbursts. Some scientists believe that if there is a supernova explosion in "Seamount II", it may also lead to the extinction of human civilization.

S Swordfish: In the galaxy called the Large Magellanic Nebula, in the direction of the southern constellation Swordfish.

Pistol Star: Near the center of the Milky Way, in the constellation Sagittarius. The mass of a pistol star may be 150 times that of the Sun, and the luminosity of the Sun is 1.7 million times that of the Sun

LBV1806-20: Also a high-light even-degree blue variable star or binary star, located 30,000–49,000 light-years from the Solar System, near the center of the Milky Way. It is the most massive and brightest star ever discovered by mankind.

......

Although human civilization does not have the full ability and energy to study every star in the universe at close range, this does not mean that there will be no opportunities in the future.

Yuan has never forgotten his original dream, and firmly believes that one day, he will have the opportunity to contact and study these stars.

And this time, the proximity to the star Cygnus P is a very valuable opportunity.

Because, on an astronomical scale, supergiants are very massive, so their lifetimes are also very short, often only a few million years, which is dwarfed by the tens of billions of years of life spans of other stars. Because of this, supergiants like Cygnid P are rare.

However, not everyone is in favor of going to the Cygnus P star system, and some scientists' concerns are not unfounded.

In fact, getting close to Cygnus P is risky. As the luminosity of a star increases with mass, the luminosity of a supergiant star often approaches the Eddington limit. To put it simply, the inward gravitational pressure is equal to the brightness of the outward radiant pressure.

Above the Eddington limit, the star produces an excess of radiation that ejects parts of its outer layer. Therefore, if an excess of radiation happens to occur when the expeditionary force is close to Cygnus P, it will undoubtedly become a disaster for the expeditionary fleet.

"Laura, Wang Yao, you must always pay close attention to the operation of Cygnus P, although she is far more stable than Seamount II, but be prepared, if Cygnus P has a tendency to increase brightly, we must immediately cancel the scientific research work and escape!"

Yuan is also very aware of the risks, so the whole process must be safe and proper.

"Yes!!"

"We'll keep you informed."

Scientific commanders Laura and Wang Yao replied earnestly.

"Okay."

......

At this time, the expeditionary fleet was still 36.1 light-years away from the star Cygnus P.

In order to reduce the risk, the expeditionary force does not deliberately adjust the route to get closer to Cygnus P. According to the plan, when the expeditionary force is about 20 light-years away from the star Cygnus P, a special scientific expedition fleet will be sent into her sphere. The main body of the expeditionary force fleet will keep a distance and pass by the star Cygnus P.

On the largest observation deck of the space carrier, through the huge virtual porthole, Yuan Haochen can clearly see the cosmic starry sky restored by the information system.

The virtual porthole is actually just a curved high-precision screen that is one kilometer long and 600 meters wide, and the computer system collects the starry sky under faster-than-light travel, repairs it, and simulates it on the porthole of the observation deck.

Standing in the curved observation deck is like standing in the universe, and it is as if you are standing on the highest mountain, facing the slight cold wind, looking up at the beautiful starry sky.

In his spare time, Yuan often comes to the observation deck to pass the time and relax.

As a child, in the clear night sky of the countryside, Yuan could clearly see nearly 5,000 stars in the sky, all of them with an apparent magnitude higher than 6. At that time, although he was full of reverie about the universe and the starry sky, he did not realize that only a small part of all the stars shining in the sky were close to the size and brightness of the sun, and all the other stars were bigger and brighter than the sun.

Nowadays, in the distant universe, the starry sky that can be observed with the naked eye is very different.

At this moment, the brightest star in the canopy is none other than P Cygnus.

The brightest star in the night sky!

She seemed to glow faintly with a blue light.

The blue light was so soft, dancing and stretching in the darkness......

Blue is a cool color, and from the human senses, the blue star Cygnus P gives people a cold and sad feeling. But in fact, she is one of the hottest stars in the universe.

After staring at Cygnus P for a long time, Yuan Haochen set his eyes on another area.

The area was pitch black, and there was nothing to gain from it with the naked eye. However, Yuan Haochen could not be clearer that that direction was the target of this expedition - Cygnus X-1.

In the Cygnus X-1 binary system, there is not only a black hole, but also a blue supergiant (HDE226868, O9.7Iab). This blue supergiant star has only half the mass of the star Cygnus P.

"What does the Cygnus X-1 binary system look like?"

Yuan Haochen took a long breath leisurely, and began to think of that beautiful, magnificent picture in his mind.

"I really want to see the natural black hole in this universe with my own eyes!"

During the long journey, even Yuan Haochen would have some light fantasies from time to time, as if he had arrived at the Cygnus X-1 far away in the sky in a blink of an eye......

PS: I wish you all a happy new year in advance, and wish every friend on the way home a smooth journey and reunite with their families as soon as possible, and thank you for your support.