Giant stars are another stage in the evolution of dwarf stars. For example, the sun is now billion years old. In the next few billion years, the volume of the sun will gradually increase. This increase is caused by the continuous loss of mass by the star. The larger the mass, the stronger the gravity. When the mass of the star is lost, the gravity will weaken, causing the volume of the star to increase. Therefore, giant stars can also be called old stars. Arcturus is an old star, which is 7 billion years old. Although its mass is only 8% larger than that of the sun, its radius is more than 25 suns. Yan Xia sat in the cabin and could see Arcturus with the naked eye, because it was so bright, 170 times brighter than the sun. Even if the invisible band was subtracted, Arcturus was bright enough. When we got here, we were actually not far from the solar system. Arcturus was only more than 30 light years away from the sun, and it would take about 500 years to return to the solar system. Thinking of this, Yan Xia asked Ella: "What is the situation of the solar system now?" After all, that was his hometown. To be honest, because the time was too long, Yan Xia almost forgot what the city he lived in looked like. Ordinary people can forget the environment of the place they lived 10 or 20 years ago when they reach the age of 30. How many years has Yan Xia lived?
Yan Xia called up his virtual interface and looked at the time. 24381 AD It has been more than 15,000 years since this time. How long is the history of human civilization? "The solar system is still in an unstable state. Among the seven planets, Mercury has disappeared like the earth. Now there are only six planets. The orbits of these six planets have a certain deflection." "Mars is closer to the sun and is more suitable for living than more than 20,000 years ago. Venus's orbit has become elliptical and extremely unstable, but the atmosphere on the surface of the planet has been blown away a lot, and it can also be immigrated." "The best time to return to the solar system is 70,000 years later. By then, the solar system will be more stable than it is now. Even if it is not as good as before, with our current scientific and technological means, we can rebuild the solar system at the lowest cost." Yan Xia pondered for a moment. "Then let's set the plan for 70,000 years later." He was not in a hurry. After all, what he missed was actually only the Earth. Only there was the mark of mankind. There were too few other places, less than one trillionth. The Earth had been destroyed and fell into the sun. The high temperature had vaporized the Earth, and nothing was left. 14 years later. The sightseeing spacecraft arrived at Arcturus, also known as α-Boötes. It is a rare single star system. Humans have not found planets orbiting it in the 21st century, but Yan Xia's data showed that there is a planet in Arcturus. α-Boötes b The radius of this planet is only 2/3 of the Earth, and its mass is only slightly larger than Mars. Its orbit is also very close to Arcturus, and it almost does not rotate. It is expected that it will be tidally locked by Arcturus in 600 million years. And their destination this time is on this planet. The sightseeing spacecraft rushed into α-Boötes b in the terrifying high temperature. This planet has a very thick atmosphere. It is not formed naturally, but was transformed after being contracted by a company in the Federation. Because α-Boötes b is close enough to α-Boötes, the surface temperature of α-Boötes b can reach more than 1300 degrees Celsius. After it has an atmosphere, the temperature of α-Boötes b soars to 1600 degrees Celsius. After that, the company had to spend a lot of money to customize hundreds of combined planetary refrigeration devices, also known as planetary refrigerators, to maintain the constant temperature inside the planetary atmosphere through refrigeration technology. When the sightseeing spacecraft entered the atmosphere, it first passed through a layer of clouds as thick as 7 kilometers. After penetrating, it instantly felt like the clouds were cleared and the sky was bright.
α-Boötes b is a pure ocean planet. There is no land or island here. The water was also transported by the contracting company. A large amount of oxygen was compressed and transported here, and then hydrogen from fusion was directly collected from the interior of the star, and the technology was used to directly reduce it to hydrogen atoms. After combining hydrogen atoms and oxygen atoms, this ocean was created. The average depth of this ocean is about 27,000 meters, and the deepest point can reach 30,829 meters. The total amount of water is times the total amount of water on Earth. At this time, other tourists also woke up and looked at the ocean below through the glass. "The boiling sea is indeed worthy of its reputation." "The ocean is indeed boiling." Although α-b of Boötes does have a planetary refrigerator to help cool down, the temperature is still very high, with an average temperature of about 115 degrees Celsius, which has not reached room temperature. This causes the water on the planet to be in a boiling state all the time, and it is precisely because of this that such thick clouds can be formed to block the strong infrared and ultraviolet rays of Arcturus and other high-radiation invisible light. The sightseeing spacecraft flew a distance in the atmosphere and found a huge vortex on the sea surface. In the center of the vortex, there is a bottomless pit with a diameter of more than 300 meters. The sightseeing spacecraft flew directly into it. After going down, you can see the endless turbulence surrounding the spacecraft, which looks extremely thrilling. It feels like the spacecraft will be directly smashed if it touches the turbulence. At this time, the spacecraft has slowed down to 100 kilometers per hour. After only flying for 1 minute, the spacecraft reached the bottom of the turbulence and then entered the water. At this time, the surroundings can be seen very clearly. They are in a huge transparent pipe. The surrounding ocean should be dark. After all, it is already 1,700 meters underwater. However, the surrounding ocean is unusually bright. There are a large number of luminous plants, minerals, and animals here. There are schools of fish swimming over the pipes. They emit soft blue and white light, overlapping and crowded together, magnificent and magnificent. A giant fish over 50 meters long suddenly rushed out, opened its mouth and swallowed hundreds of fish directly, which was shocking. In the distance, a colorful light group with a diameter of 500 meters suddenly moved. It was originally thought that the reef was covered with various luminous plants, but it turned out to be a jellyfish. "Everyone, we are now at the last sightseeing spot of this journey, the Boiling Sea." "Here, there are a total of 298,908 species, of which more than 80% of the creatures can glow, which also creates a colorful underwater wonder under the Boiling Sea." "Now we are heading to the Xiaguangdi City in the Boiling Sea. This is the only city in the Boiling Sea. It covers an area of 64,000 square kilometers. After entering the Xiaguangdi City, you can move freely." The Xiaguangdi City is not only the last attraction of the sightseeing spacecraft, but also the destination of Yan Xia and Ella. Because it also has the largest biological research center in the Civilization Federation.