Two Comets, Airglow, and Aurora

This timely image from the southeastern shore of Australia in Victoria has captured two approaching comets in the early morning sky, both just passed naked eye visibility at the imaging time and formed interesting and diverse cometary tails even visible in this wide angle nightscape photo. In this view comet Lemmon (C/2012 F6) appears near the Small Magellanic Cloud (a Milky Way’s dwarf satellite galaxy). Comet PanSTARRS (C/2011 L4) is on the left with its fan-shaped tail. The green cast on the image is made by active airglow (faint natural emission of the Earth upper atmosphere). The red cast near the horizon was a burst of aurora australis. Click on the second photo to see a close-up view of comet Lemmon passing against the Small magellanic Cloud, featured as an Astronomy Picture of the Day. The Lemmon’s lime green coma and thin tail are visible in the telephoto scene, a single frame from this timelapse video. Another southern sky treasure is visible in the view: the impressive globular cluster 47 Tucanae. © Alex Cherney