The Przybylski star rotates very slowly, learned astronomers

02.05.2018

European astronomers studied the stars and Przybylski found that one revolution around its axis it makes for about 200 years. These findings are important for the understanding of chemically peculiar (unusual) stars.

Located at a distance of about 370 light years from Earth, the Przybylski's star (also known as HD 101065) is a rapidly oscillating star, spectral class Ap (a type of chemically peculiar stars), which is in the sky in the direction of the constellation Centaurus. This star was the object of numerous observations, as astronomers are attracted by the unusual chemical composition of this star.

Although many important properties of the star were discovered by astronomers earlier, however, the period of its own rotation still remained a mystery. It was known only that this period is, within wide limits of from 12 hours to 300 years.

In the new work, a team of astronomers under the guidance of Svetlana Hubrig (Swetlana Hubrig) from the Potsdam astrophysical Institute, Germany, studied the magnetic and pulsation variability of the star Przybylski. This study is based on observations conducted in the period between June 2015 and June 2017 using the High Accuracy Radial velocity Planet Searcher polarimeter (HARPSpol) installed on the 3.6-meter telescope of the European southern Observatory situated in Chile. During the study, scientists discovered that the period of rotation of the star around its own axis is about 188 years. This calculation was based on the analysis of all available information on the longitudinal measurements of the magnetic field of the star and on the assumption of its dipole structure.

The study was published in the journal Monthly Notices of the Royal Astronomical Society.