2017 Jan 04 UPDATE: (846) LIPPERTA is one of the Themis family and reaches an extremely favourable opposition on 2017 January 06.5 when it can be seen from the Earth at a phase angle of just 0.06 degrees. It is currently magnitude 14 and lies in the constellation of Gemini, preceding the star Delta Geminorum by 1-2 degrees. CCD observations through a V filter will be especially valuable over the next few nights. In particular, sets of say 10 exposures at intervals during the nights of January 5/6 and January 6/7 would be ideal. Observers are encouraged to use remote telescopes with the aim of 24-hour coverage. 


Dear Observer,

Thank you for joining me in this latest observing campaign, which aims to 
achieve high-precision photometry of asteroids that pass through a minimum 
phase angle of 0.20 degrees or less.

The current target, (846) Lipperta reached a phase angle of 0.056 degrees at 
12 Noon today. I can report that we have good coverage of this event despite 
the fact that it was daylight in the UK at that time, thanks to 0.4-m and 
2.0-m Las Cumbres Observatory telescopes in Australia and Hawaii.

The phase angle (PhA) was so low that if you had been standing on Lipperta, 
you would have seen the Earth transit the Sun taking over about 12 hours to 
traverse its disk, during which time any opposition surge has to plateau in 
brightness. It'll be interesting when we have finished the project at the 
end of May to actually extract this plateau effect from the data in quite 
some detail. We should be able to do this thanks to the objects exceedingly 
slow spin rate (Period ~68 d ?).

Do keep up the good work in the weeks to come.

Clear Skies,
Richard Miles
BAA

2017 January 06 18:07