Britastra occultation!

On Friday Sept 22nd at 21:27 UT (22:27 BST) [observe from 21:25 – 21:29 UT], the asteroid (4522) Britastra is predicted to occult star TYC 6890-00327-1, of 9.3 magnitude in Sagittarius [= SAO 188432]. The altitude of the star at this time (in S. UK) is 12 degrees, in azimuth 204. The asteroid was named for the Association and no previous occultations have been reported. So this opportunity could be a very nice “first”.

Path where the occultation can be observed – click to enlarge. Credit with permission: Mike Kretlow (IOTA/ES)
The star is bright enough for visual observers with a small telescope, so simple equipment is needed such as audio recording (use a smartphone) and two time points on the sound recording using a UT time signal (start and end). The sound recording can be analysed with Audacity. Web cams on telescopes can be time-marked using the recording software via the PC clock (in sync with UT). Those without any recording equipment could note if an event happened and the approximate time and duration of the disappearance of the star.

The maximum duration of this event is 9 seconds, so observers with CCDs could try rapid frame collection with minimum delay between frames.

An update to the track was issued by M. Kretlow on Sept 14th. The difference between this and UKOCL is small (about 1 path width) so please continue to observe. The actual path would be revealed by observation. Please send reports to the Asteroids and Remote Planets Section (Occultations). Good luck


Tim Haymes
tvh dot observatory AT btinternet dot com
Asteroids and Remote Planets Section – Occultations

Observations which BAA members have uploaded to their BAA Member Pages of Asteroids can be viewed here.

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