Observation by Peter Tickner: Betelgeuse, Rigel and Bellatrix

Uploaded by

Peter Tickner


Peter Tickner


2020 Feb 20 - 20:00


2020 Feb 23 - 00:20



  • ZWO ASI071 MC Pro CMOS camera
  • 14inch LX200 SCT at f/10
  • EQ8 mount
  • OAG with Lodestar X2 Autoguider
  • IR Cut filter

Urban Berkshire

Target name



Betelgeuse, Rigel and Bellatrix

About this image

This isn't scientific, especially as I had an IR Cut filter on, but I wanted to compare the relative image sizes of Betelgeuse in its current dimming phase to Rigel and Bellatrix, as the brighter the object, the larger the area it occupies on the camera image.  Betelgeuse usually varies magnitude from 0 to 1.3, Rigel 0.17 to 0.22 and Bellatrix is 1.65. In the image Betelgeuse is in the centre and compared with  a negative image of Rigel (the dark red outer area) in size below and Bellatrix above (with Betelgeuse in negative blue).  This shows that Betelgeuse is currently much fainter than Rigel and only slightly brighter than Bellatrix.

No doubt there is a way to use the raw image data to measure actual brightness and I'd be happy to be shown how.


Files associated with this observation
Like this image
Copyright of all images and other observations submitted to the BAA remains with the owner of the work. Reproduction of work by third parties is expressly forbidden without the consent of the copyright holder. By submitting images to this online gallery, you grant the BAA permission to reproduce them in any of our publications.