Scientists have investigated the red giant XX Trianguli. This giant star is covered with spots the size of the Sun. However, another striking thing is that, unlike our luminary, their change is chaotic.
Exploration of a giant star
Researchers from the Leibniz Institute for Astrophysics in Potsdam (AIP) and the HUN-REN Research Center for Astronomy and Earth Sciences (HUN-REN RCAES) have published the results of their study of the activity cycle of XX Trianguli star and found that the giant spots on it change chaotically.
XX Trianguli is a red giant located 630 light-years away from us. It is interesting because its photometric center, that is, the brightest point can shift by up to 10% of the geometric center.
For quite some time now, scientists have realized that the cause of this is the movement of dark spots on the surface. For 16 years, the STELLA AIP telescope, located on the island of Tenerife, has made more than 2,000 observations of this star. Thanks to this, scientists have learned amazing things about it.
Chaotic movement of giant spots
The first thing scientists have learned about XX Trianguli is that there are really giant spots moving across the star’s surface. The size of some of them approaches the size of the Sun. No wonder the brightness of a star varies so much.
Thanks to observations, scientists learned that the rotation period of the XX Trianguli is 24 days, and the spots obey this pattern. All of this is very similar to what happens on the Sun with the dark areas around which flares occur.
But beyond that, the behavior of the spots on XX Trianguli has little to do with our luminosity. The number of spots on the Sun experiences an increase and decrease over time during an 11-year cycle. This is due to the magnetic dipole inside the star.
On XX Trianguli, on the contrary, the spots change from year to year in a chaotic manner. This means that there is no cycle of activity there. The dynamo within the star is in a chaotic state.
Provided by www.space.com
