2019-02-13 09:24:46 Source: Beijing Daily
The Science Story in "The Wandering Earth"
On the first day of the Moonlight New Year, the Chinese movie Windward Earth landed in the big theaters and won the box office championship at the highly competitive spring festival. The film is based on Liu Tsesin's science fiction novel, which tells a story that happens in the near future: the sun is getting old and it is possible to enter the red giant expansion phase at any time and the earth will be swallowed. At this critical moment, for the survival of the people on earth, the United Republic of Earth has urgently decided to build tens of thousands of planetary fusion engines on Earth, each of which generates billions of tons of load and treats land as land. A huge spacecraft sails from the existing orbit and heads to a star closest to the Solar System, the next star that finds the interstellar journey of 2500 years.
Today it is interesting to talk about some of the scientific stories included in the film.
When Will the Sun Die?
The sun was born in a nebula, which was about 5 billion years ago, and followed the other planets in the solar system. The energy supplied by the sun comes from the nuclear reaction of its central hydrogen, similar to a large number of hydrogen bombs exploding in the sun, according to existing data, this type of nuclear reaction will last about 10 billion years, so the sun will burn another 5 billion . About a year.
In the "Wandering Land" novel, scientists have discovered that the sun is unusual and predicted that the sun will enter the expansion stage of the red giant star, flooding the Earth's orbit over the next few hundred years. The red giant star is a short period of instability experienced by the burning of stars. However, anthropologists have calculated that humans may exist on Earth for about 2 million years due to various environmental changes. Physicist Hawking was even more pessimistic about the inefficiency of human energy use, and the prophecy had to think of leaving the Earth in a few hundred years.
At some point, the Earth has moved out of the habitable zone of the Solar System before being submerged is no longer suitable for life, but at that time Mars will completely enter the habitable zone.
The adjacent star is a possible destination?
Centaur is Earth's closest star except the Sun, 4.2 light years away. If there really is a "Wandering Earth" program, Earth really wanders around Centaur to the next star, where is it suitable for the survival of the human environment?
According to a number of observations from powerful telescopes like Hubble for centaur stars, we still can learn a lot about this star. The adjacent star of Centauri is only a seventh of the mass of the sun belonging to the red dwarf, whose brightness is lower than the sun.
In 1999, when Liu Zissin wrote the novel "The Wandering Earth," people do not know if Centauri has planets. At the end of 2016, the discovery of the European Southern Observatory, called the Red Point, made both astronomers and the public very excited – the scientists discovered a planet very similar to the Earth around its quality. It is about 1.3 times the mass of the Earth and has a revolutionary period of 11.2 days, located in the Centaur's habitable zone. Astronomers used a parameter called the Earth's Similarity Index to describe the similarity between the planet and the Earth, and the index of similarity for the "light red dot" reached 86%.