Scientists have often wondered about what the state of the sun will be when it dies, but a new study has finally confirmed what will likely happen many years now.

The New Theory

Professor Albert Zijlstra from the University of Manchester's School of Physics and Astronomy joined a team of international astronomers to determine what will happen to the sun after it dies in 10 billion years. Their study revealed that the sun will heat up and transform into a planetary nebula, which is typically surrounded by ionized gas.

The study was published on May 7 in the journal Nature Astronomy.

Starts that cease to exist often shoot out massive amounts of gas and dust that is called an envelope. The process of ejecting the envelope is a sign that the star is low on energy, and it is about to die.

Professor Zijlstra said that after 10,000 years of the star dying, the planetary nebula becomes bright. Their study confirms that small stars in this state can be visible from far away. 

Penn State astronomer Robin Ciardullo said that the study was, "an important step forward."

The Old Theory

25 years ago, astronomers had a different theory about the end of the sun. They suggested that stars with smaller masses, like the sun, turned into a nebulae that was not as bright as the larger stars. As a result, some nebulae were not as visible from far away.

Scientists assumed that the sun would be too faint to create a planetary nebula because of its mass. There was some despite among scientists if this theory was accurate.

How Did They Discover It?

The researchers wanted to prove that smaller stars heat up quicker in order to become a planetary nebula. This would explain why a planetary nebula with a smaller mass can be just as bright as a larger one.

They used a data-drive model to predict the brightness of the ejected envelope for stars with different masses. The model simulated the entire process of the star's ejection of the envelope. The simulation showed that younger stars with smaller masses heated up three times faster than older ones. Through these models, the researchers showed how the sun can still turn into a bright planetary nebula when it dies.

"Not only do we now have a way to measure the presence of stars of ages a few billion years in distant galaxies, which is a range that is remarkably difficult to measure, we even have found out what the sun will do when it dies," said Professor Zijslra.