Lobel, A.

Released on 2025-02-17

Abstract: A recent five-year study has uncovered new insights into the properties of Yellow Hypergiants, a heavy star class known for their dramatic outbursts. Scientists focused on Rho Cassiopeiae (Rho Cas), HR 8752, and HR 5171A, revealing that Rho Cas exhibits cyclical outbursts every 10 to 40 years, with large fluctuations of its surface temperature. Alex Lobel from the Royal Observatory of Belgium (ROB) was part of this international study that combined historical data covering 138 years. The results, published in Astronomy and Astrophysics, show that vigorous pulsations trigger these massive eruptions. They also offer a clearer understanding of the Yellow Hypergiants’ fast evolution and their potential transformation into Luminous Blue Variable stars or explosive supernovae.

Keyword(s): hypergiants ; outbursts
Note: Astronomy & Astrophysics, 2025, 694, A136 https://doi.org/10.1051/0004-6361/202449384 Title: Investigation of the pulsations, outbursts, and evolution of the Yellow Hypergiants: Rho Cas, HR 8752, HR 5171A, with notes on HD 179821 Authors: M. van Genderen, A. Lobel, R. Timmerman, E. R. Deul, A. Vos, H. Nieuwenhuijzen†, E. J. van Ballegoij, M. Sblewski, G. W. Henry, E. Blown, and G. Di Scala
Links: link; link2
Funding: Horizon2020/No.823734/EC-POEMS