2021 September 2

ASTEROID OBSERVING CAMPAIGNS FOR 2021-22

Richard Miles

That time has come when the nights are pulling in (for northern hemisphere observers!) and when we can usefully observe astronomical objects in a dark sky during an evening. I have prepared a target list of asteroids that I encourage you to image either using an unfiltered CCD camera, or one fitted with a Sloan r’, Cousins R, or Johnson V photometric filter. It’s your choice! The idea is to measure the magnitudes of each object with high accuracy. I can do the analyses if you wish – others out there do their own.

Listed below are the targets alongside their dates when they come to opposition. They are a mixture of objects – some are listed as part of our low phase angle studies, where we have a special interest in objects belonging to the Themis family of outer main-belt asteroids. Others have very slow rotation rates and we are making a study of these since they are a rather neglected class. Finally there are a few for which no accurate rotation period has been successfully determined – sometimes this is because they are relatively spherical in shape and so their lightcurve has a low amplitude:

The first two objects are the most urgent as they are due to come to opposition on September 07 and September 13.

(1247) Memoria reaches a very low phase angle and we shall be trying to catch it passing through that point in its orbit as seen from Earth when the opposition brightening effect will provide us a measure of the nature of its surface regolith, so please do try and do an observing run on the night of Tuesday 07/08 or the nights either side, weather permitting. Thanks – I look forward to receiving your observations.

Richard Miles

Director, Asteroids and Remote Planets Section