Scientists agree that the sun will die in about 5 billion years, but they weren't sure what would happen next—until now. A team of international astronomers predicts that the Sun will become a red giant, leaving behind a massive ring of illuminated stellar gas and dust, a phenomenon known as a planetary nebula.
Abell 39, object number 39 in the catalog of large nebulae discovered by George Abell in 1966 is of a large nebula discovered by George Abell in 1966, is a fine example of a planetary nebula. This photograph was taken in 1997 from the Kite Peak National Observatory in Arizona through a blue-green filter that isolates the light emitted by the oxygen atoms in the nebula at a wavelength of 500.7 nm. The diameter of the nebula is about five light years, and the thickness of the spherical shell is about a third of a light year. The nebula itself is about 7,000 light-years from Earth in the constellation Hercules. Credit: TARector (NRAO/AUI/NSF and NOAO/AURA/NSF) and BAWolpa (NOAO/AURA/NSF) WIYN
Scientists agree that the sun will die in about 5 billion years, but they weren't sure what would happen next—until now.
A team of international astronomers, including Professor Albert Zijlstra from the School of Physics and Astronomy at the University of Manchester, predicts that it will become a massive ring of stellar gas and dust - a phenomenon known as a planetary nebula.
A planetary nebula is the final destination of 90% of today's active stars, and traces the transformation of the Sun from a red giant to a degenerate white dwarf, but for years scientists were unsure if this was also the fate of our Sun, because its mass was considered too low to form a visible planetary nebula.
To find out, team members developed a new data-driven model that predicts the life cycle of stars. The model was used to predict the brightness of the envelope of material ejected from the star, for stars of different masses and ages. The study was published in the journal Nature Astronomy.
Prof. Zylstra explains: "When a star dies, it emits a huge envelope of gas and dust, which can reach up to half the star's mass. In the end what remains is the star's core, which has run out of fuel, and it shuts down and finally dies. During the short phase when the core heats up it causes the ejected mantle to shine brightly for about 10,000 years, a short period in astronomical terms. This process makes the planetary nebula visible. Some of these nebulae are so bright that they can be seen from a distance of tens of millions of light years, while the star itself is weak and its light often does not reach our eyes.
The model also solves another problem that has been troubling astronomers for about a quarter of a century.
About 25 years ago, astronomers discovered that if you look at planetary nebulae in other galaxies, the brightest ones exhibit the same brightness. It is possible to know the distance to the galaxy only by observing the brightest planetary nebulae. In theory this should be true in all types of galaxies.
The conflict was between the data and the models, the data showed it was true, but the models argued otherwise. Prof. Zylstra adds: Old, low-mass stars should form much fainter planetary nebulae than massive and therefore younger stars. It has been an enigma for all these years.”
In observations we have seen many bright planetary nebulae, left over from low-mass stars like the Sun. The models said this was impossible and that any star less than twice the mass of the Sun would produce a planetary nebula too faint to be seen."
The new models show that after the ejection of the mantle, the stars heat up 3 times more than in the old models. This makes it easy for low-mass star masses like that of the Sun to form bright planetary nebulae. The team found that according to the new models the Sun is almost at the low mass limit where visible planetary nebulae still form, albeit faintly, but smaller stars will not produce bright planetary nebulae.
Adds Prof. Zylstra: "We discovered that stars with a mass of less than 1.1 solar masses will produce pale nebulae, and stars 3 times more massive will produce bright nebulae, but for the rest, the predicted brightness is very close to the observed one. The problem was solved, after 25 years."
"Now we have a way to find the presence of stars billions of years old in distant galaxies. And also, we found out what will happen when the sun dies.
The Earth will be engulfed in the Sun's expanding mantle, along with most if not all of the planets in the Solar System, but even so, it will no longer support life long before then, in the earlier stages of the Sun's expansion.
to the notice of the researchers
More of the topic in Hayadan:
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It's just mental confusion and inventions of mind engineers.
They decided.... Good for them that they decided.
nonsense.
Man is not particularly evil, despite the consensus among the green pagans. If man was a beautiful vegetarian, as was their childhood dream, he would have been extinct a long time ago, because only preserved meat (in salt/wind/smoke) kept man alive in times of famine and drought. And most importantly: most of humanity would have become extinct (billions die of starvation because of ice and snow that prevent the possibility of agricultural crops to exist on most of the planet) if it were not for the greenhouse effect, which delays the coming of the terrible periodic ice age!!!
Our home on earth is temporary. We have a billion and a half years until the conditions are inappropriate. In my opinion much, much less. Not even a million years. Later, from a technological point of view, we will be able to migrate to other planets.
There are those who say that such an evil species should not spread, but my opinion is that it will take evolution billions of years to reach the current state. The next experiment in evolution will be no less full of suffering than the previous one.
Already now, my chances as a civilization in light of the damage we are causing in the greenhouse effect and the lack of maturity as a culture alongside technological maturity - calls into question the continuity of the human race. Specifically for the issue of coastal flooding, I see a solution by digging canals into the continent and scoring the water level in the lakes and serial water desalination which will cool the continents and fertilize the arid lands. Lack of leadership.
We'll see