Polaris: History of Pulsation Activity since Discovery

TitlePolaris: History of Pulsation Activity since Discovery
Publication TypeJournal Article
Year of Publication2017
AuthorsUsenko, IO, Kovtyukh, VV, Miroshnichenko, AS, Danford, S
Short TitleSci. innov.
SectionScientific Framework of Innovation Activities
The pulsation activity of small-amplitude Cepheid Alpha UMi (Polaris) during the period of its radial velocity observations has been analyzed. In the 20th century, Polaris was known to demonstrate a decrease in radial velocity amplitude to the minimum, in the 1980s. Thereafter, the amplitude has increased. The observations of September-December 2015 (21 spectra) obtained by 81cm telescope TCO with spectrograph have showed that radial velocity amplitude comes to 4.16 km/s and is approximately twice higher than the estimates made in 2007, with pulsation period adding 8.6 min.
KeywordsCepheids, pulsation periods, radial velocities, stars, variable amplitude, α Umi