Speculate for a moment what will happen if our sun suddenly goes out.
For an Hour
The very last photon from our sun has started there final flight towards the earth. No one yet suspects that the heart of our solar system has stopped functioning. Eight to nine mins later the sky suddenly starts turning black. No matter what your location is, the stars are clearly visible. The moon is not visible at all since there is no longer any sun light. There will be no photosynthesis and Oxygen production will be reduced.
For one Day
True panic will start now. Temperature will drop by several degrees and Earths surface began to cool. But from the inside the planet is still heated by its molten core. Dawn will not arise. Panic and chaos will start enveloping the world. State authorities will have zero control over the situation. Human kind will try to find out what the hell happened. Difficulties with power and water supply will start rising. Earth surface temperature will be 5' C to 7' C. Some species of plant and micro organism began to die. The inheritance of ocean will feel no change for the time being.
After Seven Days
It is still dark and the average temperature on Earth is now -17' C. The areas with tectonic falls are still warm. Thanks to Geo thermal energy not letting the surface freeze over. Most plants have already died due to cold and lack of light. Heat loving animals also began to die. The surface of the ocean is beginning to turn to ice. By now, scientists and other individuals have realized what has happened and rush to organised and equipped shelters.
After One Month
Earth is continuing to cool. Average temperature of Earths surface is not -30' C and the entire plant is coated with ice. All plants have died. Most of the Earths living thing has died but some bacteria still carry out with there normal life activity. Life under ocean is only near Geo thermal spring. But the drama of mass extension began's to unfold.
After One Year
Thick layer of ice will cover the ocean as will as Earth's surface. The temperature of Earth's surface will drop to -45' C. Life endorse now only deep in the Earth's ocean and perhaps some group of humans might be able to survive on the surface of the planet in places like Iceland and areas of large activity of Geo thermal.
After One Thousand Years
The Earth's surface temperature will be -160' C. At that point, any type of life on Earth will be impossible.