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Survival of planets: Earth's fate as Sun dies

Survival of planets: Earth's fate as Sun dies Will the Earth "survive" when the Sun goes out (photo: Freepik)

Even the "eternal" by human standards Sun, in 5 billion years, will approach its death. It will change its size and the amount of heat radiation, which will affect the planets in the Solar System. Some of them will not survive these changes, according to the head of the laboratory of the Main Astronomical Observatory of the NAS of Ukraine, Ivan Kriachko.

Which planets will "survive" when the Sun goes out

"In about 5 billion years, the Sun will not be the same as it is today. By then, it will become a red giant, significantly increasing in size, possibly engulfing Mercury and Venus. Even if the Sun doesn't reach Earth and Mars, it could still destroy them, causing intense tides that tear these planets apart," says the scientist.

Kriachko adds that after becoming a red giant, the Sun will transform into a white dwarf. These are very dense hot stars the size of Earth, marking the final stage of a star's evolution.

"Until recently, astronomers had no idea what could happen to planets on distant orbits when their parent star becomes a white dwarf. Observing exoplanets near such stars using the transit or radial velocity method is difficult. Despite these challenges, astronomers have already found evidence of exoplanets around such "cinders of stars," adds the astronomer.

The scientist also notes that in 2011, the NASA telescope spotted a potential planet orbiting a white dwarf, but its orbit was 2,500 times larger than the Earth-Sun orbit. However, astronomers have not yet observed orbits similar to Jupiter and Saturn around white dwarfs.

"But everything changed with the James Webb telescope. This telescope was chosen by a group of scientists to study white dwarfs within 75 light-years. They discovered planets similar in size to Jupiter and Saturn. Thus, scientists obtained evidence that these planets will "survive" when our sun becomes a white dwarf," explains Kriachko.

If the discovery is confirmed, it would mean that there are many similar planets that can be studied using the James Webb telescope, as two out of the four white dwarfs studied have exoplanets.

"This will also indicate that there is a chance for the outer planets of the Solar System to remain intact when the sun becomes a white dwarf," adds the astronomer.

Recall that the outer planets of our system include Jupiter, Saturn, Uranus, and Neptune."

Earlier, we wrote about the unique astronomical phenomena that Ukrainians will be able to observe in 2024.