Question: What year will the sun become a new nebula
About the article "Nebula", section "Planetary nebulae".

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Dos EPs is a compilation album by rock trio Nebula.
It contains the Nebula songs from the Nebula/Lowrider EP, Sun Creature EP and 3 new songs. 
Little Ghost Nebula is a planetary nebula in the constellation Ophiuchus.
It was discovered by William Herschel.
Round and planet-shaped, the nebula is also relatively faint.
Planetary nebulae are not related to planets at all, but instead are created at the end of a sun-like star's life as its outer layers expand into space while the star's core shrinks to become a white dwarf.
The transformed white dwarf star, seen near the center, radiates strongly at ultraviolet wavelengths and powers the expanding nebula's glow.
The nebula's main ring structure is about a light-year across and the glow from ionized oxygen, hydrogen, and nitrogen atoms are colored blue, green, and red respectively. 
In around 5 billion years the Sun will have exhausted the hydrogen fuel in its core and will begin to expand.
At its largest, it will approximately reach the orbit of the Earth, before losing its atmosphere completely as a planetary nebula and leaving the core to become a white dwarf.
The evolution of the Sun into and through the red-giant phase has been extensively modelled, but it is still unclear whether the Earth will be engulfed by the Sun or will barely survive.
At its brightest, the red-giant Sun will be several thousand times more luminous than today but be at about half the temperature. 
If the Earth manages to escape incineration from the red giant Sun 7.9 billion years from now, its future remains bleak.
After fusing helium in its core to carbon, the Sun will begin to collapse again, but will fail to fuse carbon, because in low-mass stars like the Sun, the stellar core will never achieve the pressure and temperature necessary for fusing carbon in its core.
The Sun will then "pulsate" multiple times before shedding its outer layers into space in what is known as a planetary nebula.
Its core will stay behind and become a white dwarf star.
All the remaining planets, including the Earth, will start to cool rapidly and be dark, frigid planets devoid of any life.
After cooling for billions (maybe trillions) of years, the Sun will cool to the point at which it can no longer emit any visible light.
It will have become a black dwarf star.
In about 30 trillion years the black dwarf Sun will undergo an encounter with another star from the local stellar neighborhood.
When two stars pass close to each other, their planets' orbits can be disrupted, potentially ejecting them from the system entirely.
The Earth could be ejected from the Solar System if the passing star were close to Earth's orbit.
Hence, if Earth escapes intergalactic ejection from the Solar System, then in about 1020 (100 quintillion) years, the Earth's orbit will finally decay from emission of gravitational radiation.
The Earth will gradually fall inwards towards the Sun, then finally be ripped apart by tidal forces once it closes to a distance of around 1-6 radii from the Sun. 
Once the Sun stops fusing helium in its core and ejects its layers in a planetary nebula in 8 billion years, it will become a white dwarf and, over billions of years time, eventually will no longer emit any light.
After that, the Sun will not be visible to the naked human eye, removing it from view.
The estimated time for the Sun to cool enough to become a black dwarf is about 1015 (1 quadrillion) years, though it could take much longer than this, if weakly interacting massive particles exist.