Astronomy - This solar system could tell us how Earth may evolve

An old star may be a sneak peak at what Earth will be like in the future

A composite view of evolved star L2 Puppis in visible light

CNRS/U. de Chile/Observatoire de Paris/LESIA/ESO/ALMA

An international team of astronomers has been studying the star L2 Puppis to see what kind of future is in store for Earth.

The team used the ALMA radio telescope to study L2 Puppis, which is about 208 light-years away from Earth. Through the study, the team discovered that the star has a lot in common with our Sun.

“We discovered that L2 Puppis is about 10 billion years old,” Ward Homan from the KU Leuven Institute of Astronomy said in a press release. “Five billion years ago, the star was an almost perfect twin of our Sun as it is today, with the same mass. One third of this mass was lost during the evolution of the star. The same will happen with our Sun in the very distant future.”

Professor Leen Decin from the KY Leuven Institute of Astronomy said that in a few billion years, the Sun will become a red giant star and be 100 times bigger than it is right now, among other anticipated changes.

“[The Sun] will also experience an intense mass loss through a very strong stellar wind,” Decin said. “The end product of its evolution, 7 billion years from now, will be a tiny white dwarf star. This will be about the size of the Earth, but much heavier: one tea spoon of white dwarf material weights about 5 tons.”

About twice the distance from the Sun to the Earth, the team found an object orbiting L2 Puppis that may show what Earth will look like after some time.

Not only will this change impact Earth, but it will also affect the rest of the Solar System. While Mercury and Venus will be engulfed and destroyed, Earth’s fate is still up in the air.

“We already know that our Sun will be bigger and brighter, so that it will probably destroy any form of life on our planet,” Decin said. “But will the Earth’s rocky core survive the red giant phase and continue orbiting the white dwarf?”

It’s not sure yet if Earth will survive the Sun or lose the battle, but studying L2 Puppis may show us Earth’s fate.