The age of the sun is about 4.6 billion years, and in 2018, astronomers proved that when the sun dies, it will turn into a planetary nebula, which is a bright bubble of cosmic gas and dust.
Based on the results of observing other stars, astronomers expect that the sun will reach the end of its life after about another 10 billion years during this period.
This means that in the first five billion years, the sun will turn into a red giant, and its center will shrink, but the outer layers of our giant star will expand until it reaches the orbit of Mars, engulfing our planet in the process.
Scientists predicted that humanity would have ended by that time, noting that, according to estimates, there is only a billion years left for humanity unless we find a way to leave the planet.
The sun’s brightness increases by about 10% every billion years, and this brightness gradually ends life on the planet, as the oceans evaporate, and the surface of the globe will become so hot that it is impossible to form water.
A 2018 study used computer modeling. Like 90 percent of other stars, our sun is expected to shrink from a red giant to become a white dwarf and then end as a planetary nebula.
“When a star dies, it ejects a mass of gas and dust, known as an envelope,” explained astrophysicist Albert Zylstra of the University of Manchester in the UK.
He added, “When the sun dies and the envelope is formed, this will reveal the flaming center of the sun, which is at this stage on its way to death. This hot center makes the atmosphere shine brightly for about 10,000 years, which is what makes the planetary nebula visible.
This, and recent studies succeeded in predicting that any star less than twice the mass of the sun will give a planetary nebula too faint to be seen, and also confirmed that the sun is approaching the minimum mass of a star that can produce a visible nebula. For this reason, it is expected that when the sun dies, it will produce a faint planetary nebula that cannot be seen.