|
As you suggest Craig there are limitations to what I can detect. The spin parameters of several thousand asteroids are known and the current scientific explanation for very slow spinners is YORP or Tumbling. But the YORP theory only works for small inner main belt (or closer) asteroids and then the amount of dampening is limited to the age of the solar system.
My observations are in contrast to the paradigm which, given the situation that the target is low amplitude (only 3 times the catalogue error - on the lower limit of acceptable) and the noise in my data has a typical RMS of 0.015 - 0.018mag, means the periodicy that I see could just be coincidence or convenient patterns in the "noise".
If I can't explain "how", my data is then called into question (such is the life of an amateur) which is rather annoying after 3 months work.....
Within the next 2 years the current 2MASS catalogue will be replaced by the APASS catalogue and the catalogue errors will be reduced from 0.05 to 0.02mag. A re-measure with the new catalogue will provide more reliable results.
(FYI - the 2MASS catalogue and algorithms inside MPO Canopus allow observers to take unfiltered observations and link nightly sessions without the need for absolute photometry. The results are not on the standard system but they are close and it also allows different observers using the same process and catalogue to link their sessions to within 0.05mag. Gone are the days of artificially altering the magnitude zero points of data sets to align sessions to fit curves and determine periods)
Cheers
|