Little Glasses said, "Li Xin, didn't you say you brought coffee? I want to drink coffee." ”

Li Xin said: "Why don't you drink coffee again tomorrow morning, okay? You just drank beer, and drinking coffee now is probably not good for your health." Besides, you guys are so excited today, it's already night, and now that you've drunk coffee, you don't want to sleep tonight. If you don't sleep well tonight, you won't be able to go to the mountains tomorrow morning to pick mushrooms. Or I'll pour you some more beer, drinking beer will help you sleep. ”

Little Glasses said, "Okay, bring me a little more." ”

Li Xin picked up the beer bottle and poured beer into her glass: "That's right, coffee will be drunk tomorrow morning, and then you can experience what it is like to watch the rising sun, listen to the birds, eat toast, and drink milk and coffee." I dare to pack tickets, it will definitely be better than watching the sunset with a beer tonight!"

"You can't say any more, I can't wait for time to travel to tomorrow morning now, so I can drink coffee, eat toast bread, and watch the sun rise!"

The old girl teased her: "Then you still can't look at the stars, do you want to sleep in the tent?"

Little glasses said, "I can't take care of it!"

Jiang Xiaolan touched her forehead: "I don't have a fever, why are you talking nonsense now, are you drunk?"

Little glasses said, "No, two beers and get drunk?"

Jiang Xiaolan smiled: "Then why did you say one sentence to the other?"

"It's all the scenery, the sunset and the night are so beautiful, I can't imagine what tomorrow morning will be." ”

Before I knew it, it was 8:30 p.m., and seeing that everyone had eaten almost, Li Xin suggested: "Why don't we clean up and go to the lake." ”

Jiang Xiaolan said: "This is a good idea, let's go wash the dishes, you clean up the tables, chairs and benches here, and we will leave when we come back after washing the dishes." ”

A few girls turned on flashlights, brought pots and pans to the sink to wash dishes, Li Xin folded up the tables, chairs and benches and put them away, and took down the camping lamp hanging on the top of the canopy and took it back to the tent.

When the girls came back from washing the dishes, Li Xin was ready to go.

The old girl asked, "What if we all leave and the things in the tent are lost?"

Li Xin said: "Probably not, there are still a lot of camping people around, you just need to bring your valuables with you, and other things are fine in the tent, isn't it just some clothes, bedding or something? It's a little chilly at night, so you'd better wear a jacket. ”

A few girls packed up their things and followed Li Xin for a walk along the trail by the lake.

There was no moon in the sky, it was pitch black all around, and nothing else could be seen except for the range of the flashlight in Li Xin's hand. Not only that, but there was silence all around, except for the faint sound of crickets in the distance.

If you were in the city, you would hear cars, horns, advertisements, all kinds of noisy noises, but here, it's all gone.

The old girl pointed to the clear night sky and said, "Look at it, there are so many stars in the sky!"

The little biscuit also said, "Really, there are so many, why can't you see it when you were eating just now?"

Li Xin said: "When we were eating just now, there was a camping lamp hanging on our heads, the light was too strong, how could we see the stars." ”

The little glasses looked up at the sky and said, "Wow, it's like you said, the sky is full of stars!"

Jiang Xiaolan asked, "Didn't you say that there is a galaxy in the sky?"

Li Xin pointed to the night sky and said: "It should be that one, you pay attention to it is brighter than other places, but you can't see exactly where it is, it means that there are many stars on this light band, it should be the Milky Way." ”

Jiang Xiaolan asked puzzledly, "Aren't we just in the Milky Way, how can we see the Milky Way in the distance?"

Li Xin thought for a while and said, "This shouldn't be strange, the solar system is a part of the Milky Way, and the earth is in the solar system, but at the same time, we can still see the sun and the moon in the solar system, right? According to this reason, we should also be able to see the other stars of the Milky Way, as if we are standing in the center of a plate, we can see the edge of the surrounding plate." ”

Jiang Xiaolan said: "It seems to make sense." You see the Milky Way stretching across the sky in the sky, it seems to have a certain direction, oh, what direction is this?"

Li Xin said: "According to the direction of the setting of the sun today, the east-west direction of the earth at this time is perpendicular to it, so the direction of the Milky Way at this time should be north-south. ”

Little glasses said, "Li Xin, do you know any of this?"

Li Xin said: "No, no, I don't understand this, it's pure blindness." It's just that I remember the east-west direction of the sun setting today, and if I compare it with this, the Milky Way is in a north-south direction at this time, and I don't know if it's right. ”

Little glasses looked up at the starry sky and said, "There are so many stars, it's spectacular!"

Jiang Xiaolan also looked at the sky in a daze, and after a while, she asked Li Xin: "Do you say that among so many stars in the sky, will there be aliens?"

Li Xin said with certainty: "Then you still need to ask, this is almost a question that does not need to be questioned." ”

Jiang Xiaolan said: "How can you be so sure, doesn't it mean that even astronomers are still arguing about whether there will be aliens in the end?"

Li Xin said: "I really don't understand astronomy, but I think the astronomers who question whether there are aliens must have been kicked in the head by a donkey." ”

Jiang Xiaolan smiled: "You are really, why do you say that?"

Li Xin said: "This truth is very simple, according to some popular science articles, there are as many grains of sand on the earth, there are as many galaxies as there are in the universe, and there are trillions of stars in each galaxy." Even if each star is calculated by the standards of the solar system, a star has nine planets orbiting it, so how many planets are there in the universe? There are tens of trillions of planets! How can there be life on the earth among so many planets? In the face of so many planets, astronomers who think that only life exists on the earth are as stupid as those who burned Copernicus because he opposed the geocentric theory. ”

Jiang Xiaolan questioned: "Life on planets other than Earth is still different from that of aliens. ”

Li Xin said: "Alas, you have asked this question well, in my opinion, as long as there is life on planets other than the earth, it is almost equivalent to having aliens." ”

Jiang Xiaolan asked, "Why do you say that?"

Li Xin explained: "There is life on an extraterrestrial planet and there is no life, these are two completely different concepts, right?"

Jiang Xiaolan nodded and said, "That's right." ”

Li Xin continued: "Well, once it is admitted that there will be life on an extraterrestrial planet, that is to say, there is 1 and 2, and there is 2 and 3, and it is absolutely impossible for there to be life on only one extraterrestrial planet. Because it shouldn't be hard to figure out how ignorant and stupid to think that there is only one extraterrestrial planet with life on Earth in this case, right?"

Jiang Xiaolan thought for a while and said, "It seems to make sense." ”

Li Xin said: "Well, that is to say, once there is life on an extraterrestrial planet, there may be countless such extraterrestrial planets. Or if we zoom it down a bit, there will be at least 10 extraterrestrial planets with life, and there should be no doubt about that, right?"

Jiang Xiaolan said: "It's possible, but even if there is life on these 10 planets, it's still different from having aliens." ”

Li Xin said: "But in my opinion, as long as there is life on two extraterrestrial planets, then the probability of intelligent beings such as aliens on extraterrestrial planets is 50%!"

Jiang Xiaolan asked, "How do you say this?"

Li Xin said: "The evolution of life between stars, or between galaxies, can be said to be very different. From the perspective of the earth, the evolution of life is only a few hundred million years, and the history of human civilization is even shorter, only a few thousand years. In the tens of billions of years of cosmic development, the evolutionary process between life on Earth and life outside the earth may differ by more than a billion or even billions of years. In such a long time span, the degree of civilization of life on two different planets may differ by orders of magnitude. As I said just now, as long as there is life on two extraterrestrial planets, the intelligence level of life on one of them may be only equivalent to the level of bacteria or reptiles on the earth, while the level of civilization of life on the other planet may far exceed that of us by dozens or even hundreds of times. In their eyes, even big names like Newton and Einstein are just pediatrics. ”

Jiang Xiaolan said: "Is it so terrible?"

Li Xin said: "Absolutely, if you think about it carefully, according to the current scientific explanation, the emergence of human civilization on the earth is caused by a very, very fortuitous chance, if it were not for an extraterrestrial asteroid hitting the earth, resulting in the extinction of the dinosaurs hundreds of millions of years ago, human beings would not have had a chance to develop to the current level of civilization." If the dinosaurs had not become extinct, perhaps their level of civilization would not have been at the level of humans now, and the ancestors of humans today may have been a kind of small reptile in the eyes of dinosaurs, just like we look at ants, cockroaches and caterpillars now. ”

Jiang Xiaolan said: "You are so disgusting, describe human beings like this!"

Li Xin smiled and said, "This is a scientific inference, it is really possible that this is the case." Who would dare to say that dinosaurs wouldn't be smarter than humans today if they were given the right chance to evolve?"