Seeing a clear sky on a moonless night in central Australia was a startling experience. The Milky Way is prominent, with bright areas of star clusters and dark blotches of dust. The Large and Small Magellenic Clouds (sister galaxies of the Milky Way) hover like clouds of smoke. The sky is filled with thousands of stars, white and yellow, cream-colored, bluish and reddish. Through binoculars, the Milky Way is full of fuzzy patches of light; it was satisfying to easily pick out the globular clusters Omega Centauri and 47 Tucanae. Most patches were objects I wasn’t familiar with.

The image below is 12-minute exposure of stars moving clockwise around the south celestial pole and the smear of the Milky Way. This was a test shot I took from our campsite outside of Alice Springs. Longer time-lapse images failed when my camera battery ran out.

For a northerner, the southern sky is disorienting—the moon and planets move across the sky from right to left and the constellation of Orion is upside down. Unlike in the north where we have the North Star (Polaris) quite close to the north celestial pole (about which all the other stars appear to revolve in a counter-clockwise direction), in the southern sky, the south celestial pole is not tagged by any bright star. To locate the pole, you can use the two bright stars alpha and beta centauri to find the southern cross. The south pole is roughly half way between the southern cross and a bright star, Achernar (Alpha Eridani) [not captured in this photo]. In this time-lapse movie, watch how the stars revolve around the south celestial pole.

Taking time-lapse movies and long-exposure photos to capture star trails can be challenging. For the time-lapse movie of the southern cross rising at Lake Tekapo, New Zealand, I used an AC adapter and an inverter connected to the 12V power outlet in our rented car. The site we found for the best view of the sky was in an empty lot about a block away from the house we were staying in. It meant leaving the car with the keys in the ignition, and the tripod-mounted camera outside unattended. I couldn’t fathom staying awake out there until dawn, so I assumed that everything would be just fine leaving the car and the equipment in the empty lot. When I turned it on, the sky was perfectly clear, but after I left, clouds rolled in and the moon came up. Headlights from passing cars periodically illuminated the tree in the foreground. Here is the result.

David