Science
Pic Via NASA
In a first, a team of scientists from the Massachusetts Institute of Technology (MIT), Harvard University, and the California Institute of Technology have witnessed a significant event: the process of a dying star swallowing a planet.
The devourer star, which was equivalent in size to our Sun, engulfed a gas giant planet as massive as Jupiter.
While this event might seem gloomy, it holds great significance as it resembles the preview of what might happen to our planet when the Sun develops into a red giant and consumes three or four inner planets.
The study published in Nature claims that it is the first time astronomers have observed the swallowing part itself, although they have observed other stars before and after such an event.
Astronomers have identified many red giant stars and suspected that in some cases they consume nearby planets, but the phenomenon had never been directly observed before.
In about 5 billion years, our Sun will go through a similar aging process, possibly reaching 100 times its current diameter and becoming what’s known as a red giant. During that growth spurt, it will absorb Mercury, Venus, and possibly Earth.
“This type of event has been predicted for decades, but until now we have never actually observed how this process plays out,” said Kishalay De, an astronomer at the Massachusetts Institute of Technology in Cambridge and the study’s lead author.
Researchers discovered the event – formally called ZTF SLRN-2020 – using multiple ground-based observatories and NASA’s NEOWISE (Near-Earth Object Wide Field Infrared Survey Explorer) spacecraft, which is managed by the agency’s Jet Propulsion Laboratory.
The star is at the beginning of the final phase of its life – its red giant phase, which can last more than 100,000 years.
As the star expanded, its outer atmosphere eventually surrounded the planet. Drag from the atmosphere slowed the planet down, shrinking its orbit and eventually sending it below the star’s visible surface, like a meteor burning up in Earth’s atmosphere.
The transfer of energy caused the star to temporarily increase in size and become a few hundred times brighter.
Recent observations show the star has returned to the size and brightness it was before merging with the planet, NASA said.
Five billion years from now, when our Sun is expected to become a red giant, swallowing up Mercury, Venus, and possibly Earth, the light show should be much more subdued, according to De, since those planets are many times smaller than the Jupiter-size planet in the ZTF-captured event.
“If I were an observer looking at the solar system 5 billion years from now, I might see the Sun brighten a little, but nothing as dramatic as this, even though it will be the exact same physics at work,” he said.
Most mid-size stars will eventually become red giants, and theorists think that a handful of them consume nearby planets each year in our galaxy.
According to the NASA, the new observations provide astronomers with a template for what those events should look like, opening up the possibility of finding more.