Astronomers using the Atacama Large Millimeter/Submillimeter Array (ALMA) in norther Chile spied something strange around the dying red giant star R Sculptoris: a spiral structure thought to be made of gases being expelled by the star.
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," Maercker said. "Hence it will take longer for these elements to be blown into space - most likely, only during the next pulse."
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. The intensity of the spiral reveals how much mass was lost in each phase.
"Now that the companion star causes the spiral structure in the stellar wind from R Sculptoris, we can see it and, in a very detailed way, measure how it has evolved since the last thermal pulse," Maercker said.