(1321) Majuba is one of very many asteroids in the Solar System. It orbits around Sun with the period of 5 years and 21 days in the average distance of 2.95AU (about 450 mln km). Diameter of this asteroid is about 31km and apparent brightness is 15mag – so it is actually quite faint. Despite 10 inches of aperture I needed to set 3 minutes exposure time to achieve good SNR. I have chosen this Majuba asteroid for my new telescope first photometry test. It quickly turned out, that Majuba is both faint and also does not change its brightness much 🙁 But it is visible 🙂 According to ALCDEF database its rotation period id 5.2 hours and my data covers only about 4h, so there is still room for improvement.
Data was collected with Meade ACF 10″ telescope and QHY163M camera. Baader L filter was used and single exposure time was 180s. Both transparency and seeing were moderate. Changes in apparent asteroid brightness have two sources: changes in asteroid-Sun and asteroid-Earth distance and also asteroid rotation. Lightcurve below was created with Muniwin software.
And here is all data frames stacked into one image. Asteroid trail has one small gap due to meridian flip:
Clear skies
