... Credit Copyright: Alex Cherney ( Terrastro , TWAN ) Explanation: For now , Comet Lemmon (C/2012 F6a), and Comet PanSTARRS (C/2011 L4) are sweeping through southern skies. Lemmon's lime green coma and thin tail are near the left edge of this telephoto scene, a single frame from a timelapse video (vimeo here) recorded on February 12, tracking its motion against the background stars. ... February . ... 2011 2012 . ... Publications with keywords: comet . ... Comet Lovejoy over The Great Wall . ...