The death of the Sun is so far off as to be unimaginable. In about 5 billion years, when the sun runs out of its hydrogen fuel. The sun is a lot larger than Earth but, in fact,a white dwarf compresses to nearly the same dimensions as our planet. White dwarfs are made mostly of electron degenerate matter – electrons in the lowest energy states.
Our sun, left behind as a white dwarf after its eventually goes through helium burning will have most of its core dominated by carbon and oxygen. This core will be surrounded by a low-density layer of helium ash from the burn, and then an outer shell of unburnt hydrogen. If that phase has completed, those hydrogen layers may have been lost and white dwarfs lacking this layer are also too cool to ionize most of their surroundings.
What Does Earth Look Like When The Sun Die?
The sun is our light and life, without it Earth can not survive. The Sun will expand into a red giant in about 5 billion years and swallow the Earth. By all rights, the sun should be taking so much space that it gobbles up our planet when its size reaches a maximum. The Sun has been losing mass since long by its overall composition, however the current rate of loss is very low and occurs through the solar wind.
This interaction with UV radiation and particles in the solar wind can also mean that Earth is losing its water; Water molecules are being broken apart in the upper atmosphere. In the case of lighter hydrogen, it can even escape Earth gravity entirely. It is known from recent space missions, including the Hubble Space Telescope), that an enormous hydrogen exosphere surrounds Earth. Earth may be on track to one day look like the planet Mars, which scientists say has probably lost about 80% of its water. The Earth will be a geologically dead planet, orbiting the white dwarf remnants of our sun without an atmosphere or ocean.
The ultimate fate of the gas giants in inner solar system gives rise to a critical question with regard to what will happen to other planets when sun dies. According to simulations, the sun should lose sixteen percent and fifty-five respectively from Jupiter Saturn Uranus Neptune gas envelopes that do not begin their way in space during late evolutionary phases of a massimization of Sun case with common depression energy. Gas giants could only survive if the mass ejection during the later stages of stellar evolution and even in hot pre-white dwarfs ends quickly. Cores of hot pre-white dwarfs, left over after the ejection of the stellar envelope and planetary nebulae phase will have temperatures >100000 K with wind speeds in excess of 2000 km/s that would destroy any surviving gas giants to ultimate ashes.
What if we could engineer a new solar system after the sun died?
The material ejected in the red giant and planetary nebula phases will significantly enhance the surrounding interstellar medium with heavy elements formed by nuclear reactions during their lifetimes. This enrichment would be in carbon, nitrogen, oxygen and s-process elements such as Ba,, Zr,, La These enriched clumps mixed with contents from other made stars could form dense clouds that might collapse to create the next generation of stars.
But why the sun must die?
When a huge gas cloud, made mostly of hydrogen and helium, contains so much mass that it collapses under the force of its own gravity. The intense pressure at the core of this condensing gas blob raises its temperature to a few thousand degrees, ionizing hydrogen atoms around it. The stripped hydrogen atoms then combine to create helium atoms in the process releasing enough energy that it pushes back against compression from the force of gravity. Gravity vs the enery of fusion reactions sustain our sun and trigillions of other stars in our galaxy alone. The sun is approximately 5 billion years away from running out of hydrogen fuel, and it will then leave its stable phase. Astrophysicist Jillian Scudder said that as soon as the core exhausts its hydrogen, there will be a shell of fusion hydrogen growing around this helium-filled island. The rest of the sun will then expand, gravitional forces squeezing the core into a small space.
The sun itself will expand into a red giant when it is much older, and that would include enveloping the inner worlds including Earth in less than two billion years. It will be during this transformation that the sun enters its red giant phase, a process which is expected to last for at least another billion years. After that, the hydrogen in its outer core will burn out and helium produced by shell burning under non-degenerate conditions (which you also left your question about) starts to fuse into heavier elements: oxygen for more massive stars, carbon toward less. Those reactions will then emit less energy. The Sun will eventually contract to a white dwarf after it has exhausted all of the helium in its core and ballooned into a red giant, ejecting most of its mass as an outer shell that forms what is called planetary nebula.
Lead author, astronomer Albert Zijlstra from the University of Manchester explains: ‘When a star dies it ejects a mass of gas and dust — known as its envelope — into space. In the end, its core will turn off and die. The sun is expected to fizzle out and die in about 7 billion-8 billion years from now, astronomers say. Chances are humanity will have wiped itself out long before then.
The star is too low in mass to blow up as a supernova when it dies, but unless some external factor intervenes (such as another nearby star pulling its material off ), the remnants of IGR J17091 will likely collapse further and become a black hole. A star would need to be around 10 times the size of our sun (a solar mass) in order for it to go supernova but, should a smaller object detonate that still leaves behind quite an intense stellar remnant known as – you guessed it- a neutron star. In contrast, to form black hole a star of about 20 times the mass of sun causes supernova.
