Using the Atacama Large Millimeter/Submillimeter Array (ALMA) in northern Chile, an international team of astronomers found the spiral structure in the envelope of gas and dust around a red giant star and took a detailed three-dimensional reading of its composition, SPACE.Com reported.
The spiral is thought to be created from the gases being expelled by the dying red giant called R Sculptoris. It provides information about the velocity of the wind blowing off of R Sculptoris, revealing that the star has expelled three times as much mass as previously estimated.
"We can 'walk along' the spiral and use it as a clock to see what happened when," said Matthias Maercker, of Germany's University of Bonn.
Low- to intermediate-mass stars like the sun expand into red giants during the last stages of their evolution. When the sun reaches this stage in about 5 billion years, its outer layer will spread as far as Earth's orbit.
Every 10,000 to 50,000 years, these gaseous giants burn helium for a few hundred years in a runaway process known as a thermal pulse, causing the layers of the star to mix.
"Thermal elements are an essential part of late stellar evolution," Maercker told SPACE.Com in an email.
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"They are responsible for the formation of new elements, which eventually will get incorporated into new stars and planets," Maercker said.
By studying the corkscrewed expulsion from R Sculptoris, the astronomers calculated that the star was shedding more mass during thermal pulses than had been estimated.
"This means that much more mass is lost during a time where new elements cannot yet be incorporated into the wind. Hence it will take longer for these elements to be blown into space - most likely, only during the next pulse," Maercker said.
The spiral shape was caused by a companion star pushing through the layers expelled by T Sculptoris. The formation is allowing the scientists to study the history of the thermal pulses: Elements blown off at higher speeds create more widely separated spirals, while phases of slower mass loss are more tightly packed.
Located in the constellation Sculptor in the Southern Hemisphere, R Sculptoris is a typical red giant, so its evolution could provide a hint of what to expect from the Sun down the road, astronomers believe.
The research was published in the journal Nature.