RT @AAOastro: The predicted and measured brightness of Comet #Siding Spring from CIOC: cometcampaign.org/current-status http://t.co/hAOlWZu1Bz
RT @AAOastro: The predicted and measured brightness of Comet #Siding Spring from CIOC: cometcampaign.org/current-status http://t.co/hAOlWZu1Bz