Betelgeuse at the end of 2019: an historical minimum about to end

TL;DR

This paper presents an 8-year observational study of Betelgeuse's historic minimum brightness, including methods for visual and CCD photometry, providing insights into its variability at the end of 2019.

Contribution

It introduces a comprehensive 8-year dataset of Betelgeuse's brightness variations and discusses observational techniques for bright star photometry.

Findings

Betelgeuse reached an unprecedented minimum brightness in 2019.

The study demonstrates effective methods for visual and CCD differential photometry of bright stars.

The data provides valuable insights into the star's semi-regular variability patterns.

Abstract

The semi-regular variable star Betelgeuse is undergoing an historical minimum of its brightness. An 8 year series of visual and V-band CCD observations started at the end of 2011 is presented and discussed. Visual methods for comparing magnitudes of angularly distant stars, and performing a differential photometry, needed for such a bright star, are also presented.