If you put a hot cup of coffee in the fridge, it does not get cold immediately. Likewise, if the sun is simply "off" (which is physically impossible), the earth would remain warm for a few million years – at least compared to the surrounding space. But we surface dwellers would feel the cold much sooner than that.
Within a week, the average global surface temperature would drop below 0 ° F. In one year it would drop to -100 °. The upper layers of the oceans would freeze, but in an apocalyptic irony, this ice would isolate the deep water underneath and prevent the oceans from freezing for hundreds of thousands of years.
Millions of years later, our planet would do so. It will reach a stable -400 ° C, the temperature at which the heat radiating from the planet's core will correspond to the heat that radiates Earth into space, explains David Stevenson, Professor for planetary science at the California Institute of Technology
Microorganisms living in the earth's crust would survive, the majority of life would only enjoy a short life after the sun. Photosynthesis would stop immediately, and most plants would die in a matter of weeks.
However, large trees were able to survive for several decades thanks to the slow metabolism and significant sugar reserves. With the breakout of the lower tier of the food chain, most animals would die quickly, but scavengers plucking the dead remains could survive until the cold kills them.
People could live in submarines in the deepest and warmest parts of the ocean A more attractive option could be nuclear or geothermal habitats.
A good place to camp: Iceland. The island nation is already heating 87 percent of its homes with geothermal energy, and, says astronomy professor Eric Blackman of the University of Rochester, people could continue to use the volcanic heat for hundreds of years.
Of course, the sun is not just heat the earth; It also keeps the planet in orbit. If its mass suddenly disappeared (which is impossible, by the way), the planet would fly away like a ball swinging on a string and suddenly releasing it.
A team of international astronomers, including Professor Albert Zijlstra of the School of Physics and Astronomy, prophesied that the Sun would become a large ring of interstellar gas and dust, the so-called planetary nebula.
The planetary nebula marks the end of 90% of active life and the tracks of all stars the transition from a star to a degenerate white dwarf.
For many years, however, scientists were not sure if the sun in our galaxy would follow the same fate: it was considered too low to form a visible planetary nebula. [1
When a star dies, it ejects a mass of gas and dust – known as its shell – into outer space. The shell can be as much as half the mass of the star. This reveals the core of the star, which at this point in the life of the star has run out of fuel, which eventually leaves and eventually dies. Only then does the hot core make the ejected shell shine for about 10,000 years – a short time in astronomy. This makes the planetary nebula visible. Some are so bright that you can see them from extremely long distances of tens of millions of light years, where the star itself would have been far too weak to see.
"The data states that one can get bright planetary nebulae from small mass stars like the sun, the models said that was not possible, nothing less than about twice the mass of the sun would yield a planetary nebula that is too weak be to see him, "he said.