Lead
In 2019, China released a sci-fi movie that caused a sensation, and this is "The Wandering Earth".
At the end of the film, the movie gives a photo, and the existence of this photo is strange, because this photo was taken in the natural environment of the earth, not a scene from a science fiction movie.
This is a picture of the Earth facing the sun in the movie, and this photo is just a picture of the Earth taken from the darkest part of the sun's rays.
And this photo is something that has never been seen by humans living on Earth.
Twenty years later, when humanity finally loved to take this picture in movies, what did that picture mean?
1. Dim blue dots.
This photo of a faint blue dot was taken in 1977, and people at the time didn't feel much shock when they first looked at it, it just took a picture of a blue dot of light.
But in the 40 years that followed, the photograph slowly gained its power in people's minds.
Before this photo appeared as a popular science picture, the photo of the earth was still a kind of "computer-generated" virtual image, assuming that the earth was a huge blue point of light formed by a huge blue ocean, and humans could only say that the earth was blue.
But this 1977 photograph of the Earth is a photograph taken by humans through the rays of the sun, so the Earth presented in this photograph is the Earth that humans can perceive by themselves.
The most important feature of this picture is that all kinds of life on the earth are reduced to nothingness, only the earth's atmosphere and the reflected blue light.
This picture of the Earth was not taken on Earth, but at a distance of 37.3 million kilometers, and the final distance of this photo even reached 6.4 billion kilometers!
When the American probe "Voyager 1" flew out of the Earth's orbit and finally flew to the boundary of the universe, the Earth was already far away from "Voyager 1".
This is the Carl Brown who is in charge of the "Voyager 1" by NASA. Dr. Sagan realized that the Earth would eventually be in the perspective of Voyager 1, and that we would see the Earth as a very small, faint blue dot.
So he asked NASA to take the photo, but asked Carl to take the picture. What Sagan didn't expect was that NASA didn't like Carl very much. The reason Sagan took this photo.
Because when Voyager 1 takes pictures, the cloudy atmosphere will bring a thin layer of fog to the photos of the Earth, which will make the photos of the Earth unrealistic.
So NASA decided to take a patchwork picture of the Earth, combining multiple photos into a complete picture of the Earth, so that the interference of the vast majority of clouds could be avoided.
Cal. When Sagan heard this, he was very angry and persuaded NASA, and NASA finally agreed to let Voyager 1 take a picture of the Earth once, and if it was cloudy, take multiple shots, and finally stitch them together into a single image.
So "Voyager 1" paid a huge price for taking this photo, it took more than a year to carry out a dozen shots, and this is not the most troublesome.
Because the "Voyager 1" was floating in all directions after flying out of the earth's environment, the US probe was already in a state of constant change of posture at this time.
And Voyager 1 is still receiving the latest data from the Earth, so it is very difficult for Voyager 1 to snap a real picture of the Earth in this state.
However, because NASA people accepted the mission, and this was the last performance of Voyager 1, in the end, Voyager 1 was able to take the most realistic picture of the earth that humans could see.
This photo records the birthplace of mankind that humans will never see, but the real meaning of this photo is not to record the birthplace of mankind, but it has a very important significance in popular science.
2. The tininess of the earth.
When Voyager 1 was filmed, scientists precisely machined a picture of the Earth in the solar setting and stitched it into the sun's rays, so that the image looked like the sun was rising to its highest point, illuminating the entire universe.
When Carl. When Sagan saw this image, the first thing that came to Sagan's mind was that the Earth was a "pale dull blue dot", so he still didn't give up on the photo he wanted NASA to take.
Where is the brightest place on Earth?
No one knows this question better than NASA, which has pieced together the most realistic picture of the Earth known to mankind with a picture of the sun's rays.
The patchwork photo is unexpectedly real, not only called a "family photo" of all the planets in the solar system by American scientists, but also a "family photo of the universe", a very real picture of the earth.
In this "family photo", the other planets show their bright spots, but the Earth is very dim.
Under the sun's rays, the earth becomes very microscopic and very ghostly.
The fact that the earth is so miniature in the "family portrait" directly makes people feel the absurdity of the earth in the universe, so a researcher in the United States put forward a point of view: "We must protect it before leaving the earth."
This brings out the insignificance of the earth in the universe, intuitively the earth seems to be extremely small, but the earth has carried thousands of years of human civilization, such a big contradiction, so that human beings have a great interest in the earth, this is the enthusiasm of human beings for cosmic exploration.
Cal. Sagan saw this precisely because he wrote in "Cosmos" that when human beings can see the faint blue dot of their home while standing in the light of the sun, they must also have a very deep feeling.
The revelation that this photo can give to human beings is that every creature on the earth lives on a small planet, but this planet is only the origin, so this is the insignificance of human space exploration, but it is this insignificance that stimulates human interest in space exploration.
Then there's the first challenge of space exploration, the distance, where human technology can't detect the existence of living things where the sun rises, let alone millions of light-years away.
And if there really is life, from such a distance, being able to perceive human beings can only observe the past of human beings, because light needs a certain amount of time to transmit, whether it is technology.
So even with today's technology, what can be done is to send a greeting, but it will take millions of years, even with the lifespan of a regular human being, you can only greet people's children and grandchildren, and you are no longer there.
The second is the time of navigation, human beings can only fly with conventional power until now, so it will take hundreds of years to reach a planet in space, and this is beyond the life span of human beings.
Therefore, if human beings want to explore the universe in the future, they need to overcome these two major obstacles, whether it is distance or sailing time, it is unbearable, so human beings need to go beyond rigid thinking and find a way to the universe.
And this kind of path may be technology, or it may be that technology has developed to a certain point to be able to break down these obstacles.
3. Future exploration.
Scientists have proposed three possible exploration routes for human exploration of the universe in the future, one is that human beings try to develop a spacecraft in the last 100 years, which can reach the speed of nearly light, so it can barely reach the neighboring stars.
It only takes five years of travel to reach Mars, of course, this does not mean that any planet in the universe can reach 1510, these are only theoretical calculations, and the development of spacecraft will also take hundreds of years, and it may not be successful.
One is that in hundreds of years, humanity will have spaceships capable of traveling at the speed of light, which will be a huge spaceship that will disperse humans into different distribution points, so human exploration will become more convenient.
In a few hundred years, humanity will have spacecraft capable of traveling faster than light, which will dramatically alter the travel time between galaxies.
And the probe of the previous generation of the "Voyager" "New Horizons" has been equipped with this advanced propulsion technology, so this propulsion technology is not a legend, and in a few years, scientists will be able to conduct research on antimatter, which is well suited for faster-than-light travel.
The other is to use countless human forces to propel a small mass spaceship for interstellar travel, although this one spaceship can only travel very slowly.
There is also a kind of spacecraft that uses wormholes to achieve faster-than-light travel, and this kind of wormhole is not a theory, it needs to pass through the fire black hole, but crossing the fire black hole is a very dangerous task, and humans cannot guarantee that the spaceship will not be swallowed by the black hole.
epilogue
No matter which one it is, it is showing people that the road of human beings to explore the universe in the future is extremely lonely and bumpy, but it is also infinite, and in the future, human beings may be scattered into several settlements and continue to expand in the universe.
Humanity's exploration of the universe requires not only technological breakthroughs, but also psychological barriers, which are the distances that humans can see, which may only be perceived by humans, and may not be perceived by higher-level beings.