The rapid evolution of the central star of the Stingray Nebula — latest news from the HST

[摘要] SAO 244567 is an unusually fast evolving star. Within twenty years only, it had turned from a B-type supergiant into the central star of the Stingray Nebula. Space- and ground-based observations obtained over the last decades have revealed that its spectrum changes noticeably over just a few years, showing stellar evolution in real time. The low mass of SAO 244567 is, however, in strong contradiction with canonical post-asymptotic giant branch evolution. Thus, its fast evolution has been a mystery for decades. We present preliminary results of the non-LTE spectral analyis of the recently obtained HST/COS observations, which finally allow us to shed light on the evolutionary history of this extraordinary object.

[发布机构] Institute for Astronomy and Astrophysics, Kepler Center for Astro and Particle Physics, Eberhard Karls University, Sand 1, Tübingen; 72076, Germany^1;Instituto de Astrofísica de la Plata, UNLP-CONICET, La Plata, Buenos Aires; 1900, Argentina^2

[效力级别] 天文学 [学科分类] 天文学(综合)

[关键词] Asymptotic giant branch;Evolutionary history;Ground-based observations;Low mass;Non-LTE;Real time;Stellar evolutions