What is the final fate of Earth? It is predicted by a planet 4,000 light-years away

The discovery of an Earth-like planet 4,000 light-years away in the Milky Way Galaxy offers a preview of our planet’s likely fate billions of years from now.

By then, the Sun will have become a white dwarf, and the frozen, devastated Earth will have migrated beyond the orbit of Mars.

This distant planetary system, identified by astronomers at the University of California, Berkeley after observations using the 10-meter Keck Telescope in Hawaii, It looks very similar to the predictions of the Sun-Earth system: It consists of a white dwarf with a mass of about half the mass of the Sun and an Earth-sized relative orbiting twice the size of Earth today.

This is likely to be the fate of Earth. The Sun will eventually inflate to form a balloon larger than Earth’s orbit todaysweeping away Mercury and Venus in the process.

As the star expands to become a red giant, its decreasing mass will force the planets to migrate to farther orbits, providing Earth with a small chance of surviving farther away from the Sun.

Eventually, the red giant’s outer layers will disappear, leaving behind a dense white dwarf no larger than a planet, but with the mass of a star. If Earth survives by then, it will likely end up in an orbit twice its current size.

The discovery was published in the journal natural astronomy, Scientists look at how main sequence stars, such as the Sun, evolve through the red giant stage to become a white dwarf, and how that affects the planets around them. Some studies suggest that in the case of the Sun, this process could begin in about a billion years, eventually evaporating Earth’s oceans and doubling the radius of Earth’s orbit, if the expanding star does not engulf our planet first.

Finally, within about 8 billion years, The outer layers of the sun will disperse They will leave behind a dense, bright ball, a white dwarf, with a mass about half that of the Sun, but smaller than the size of the Earth.

“We currently have no consensus on whether a red giant Sun engulfing Earth in 6 billion years can be avoided,” study leader Qiming Zhang, a former doctoral student at UC Berkeley, said in a statement. He is now a postdoctoral fellow at the University of California San Diego.

Billion years of habitability

“Anyway, the planet Earth will only be habitable for about another billion years. “At that time Earth’s oceans will be evaporating due to runaway global warming, long before they risk being swallowed by a red giant.”

The planetary system provides an example of a planet that has survived, although it lies outside the habitable zone of a dim white dwarf and is unlikely to host life. It may have had habitable conditions at some point, when its host was still a Sun-like star.

“It is not known whether life can continue on Earth during that (red giant) period, but the most important thing is that the Sun does not devour the Earth when it becomes a red giant,” said Jessica Lu, an assistant professor at Harvard University. Chair of Astronomy at the University of California, Berkeley. “This system discovered by Keming is an example of a planet (possibly an Earth-like planet that originally had an Earth-like orbit) that survived the red giant phase of its host star.”

It was discovered through a small event

The distant planetary system, located near the bulge at the center of our galaxy, has caught the attention of astronomers, as planet Earth will only be habitable for about another billion years. 2020 when it passed in front of a more distant star and amplified the light emitted by that star by 1,000 times. The system’s gravity acted as a lens to focus and amplify the light from the background star.

The team that discovered this “microlensing event” named it KMT-2020-BLG-0414 because it was detected by the Korean Microlensing Telescope Network in the Southern Hemisphere. Zooming in on the background star (also in the Milky Way, but about 25,000 light-years away from Earth) it was just a tiny bit of light.

However, its intensity variation over about two months allowed the team to estimate that the system included a star with a mass of about half the mass of the Sun, a planet with a mass similar to that of Earth, and a very large planet with a mass of about 100,000 17 times the mass of Jupiter (possibly a brown dwarf). Brown dwarfs are failed stars, with a mass just below that needed to begin fusion in the core.

The analysis also concluded that the Earth-like planet was one to two astronomical units away from the star (about twice the distance between Earth and the Sun). It was not clear what type of host star it was because its light was lost in the glow of the magnifying background star and some nearby stars.