X-ray eruptions every 22 days from the nucleus of a nearby galaxy

Muryel Guolo, Dheeraj R. Pasham, Michal Zajaček, Eric R. Coughlin, Suvi Gezari, Petra Suková, T. Wevers, Vojtěch Witzany, Francesco Tombesi, Sjoert van Velzen, K. D. Alexander, Yuhan Yao, R. Arcodia, V. Karas, J. C. A. Miller‐Jones, Ronald A. Remillard, Keith C. Gendreau, E. C. Ferrara