The star is located 120 light-years away in the constellation of Cygnus and, on the surface, it looks just like the Sun.
"The unique combination of a star almost identical to the Sun, except for the chemical composition, with a cycle that has been observed from both the Kepler spacecraft and from ground makes this star a Rosetta Stone for the study of stellar dynamos," said Christoffer Karoff from Aarhus University in Denmark. The study can help understand how the irradiance of the Sun has changed over time, which is likely to have an effect on our climate.
For the study, detailed in the Astrophysical Journal, the team combined observations from the Kepler spacecraft with ground-based observations dating as far back as 1978, thereby reconstructing a 7.4 year cycle in this star.
By combining photometric, spectroscopic and asteroseismic data, the team collected the most detailed set of observations for a solar-like cycle in any star other than the Sun. The solar cycle is driven by the solar dynamo, which is an interplay between magnetic fields, convection and rotation.
The observations revealed that the amplitude of the cycle seen in the star's magnetic field is more than twice as strong as what is seen on the Sun, and the cycle is even stronger in visible light.