English: This light curve of Her X-1 shows long term and medium term variability. Each pair of vertical lines deliniate the eclipse of the compact object behind its companion star. In this case, the companion is a 2 Solar-mass star with a radius of nearly 4 times that of our Sun. This eclipse shows us the orbital period of the system, 1.7 days.
The long term variability shown here is precession of a disk of accreting matter around the neutron star. This precession has a 35-day period.
In addition, the neutron star in Her X-1 is also a pulsar with a 1.24 second pulse period.
Ημερομηνία
Πηγή
NASA's HEASARC: Observatories, Goddard Spaceflight Center, Uhuru observations of Hercules X-1
Δημιουργός
HEASARC Director: Dr. Alan P. Smale HEASARC Associate Director: Dr. Roger Brissenden Responsible NASA Official: Phil Newman Web Curator: Meredith Gibb
Η χρήση των λογότυπων της NASA, των εμβλημάτων και των διακριτικών της, περιορίζεται από τον αμερικάνικο νόμο 14 CFR 1221.
Ο ιστότοπος της NASA έχει μεγάλο αριθμό εικόνων από το Σοβιετικό διαστημικό πρόγραμμα και την Ρωσική Διαστημική Υπηρεσία καθώς και άλλες μη αμερικανικές διαστημικές υπηρεσίες. Αυτού του είδους οι εικόνες δεν είναι κατ' ανάγκην κοινά κτήματα.
{{Information |Description={{en|1=This light curve of Her X-1 shows long term and medium term variability. Each pair of vertical lines deliniate the eclipse of the compact object behind its companion star. In this case, the companion is a 2 Solar-mass sta