APOD: 2025 February 9 – Milky Way over the Australian Pinnacles

Good morning, Rallypoint, and welcome to the Super Bowl Sunday edition of Astronomy Picture of the Day (APOD) for February 9, 2025.

We travel to the 'Land Down Under' today for this throw-back from the APOD archives taken in Pinnacles National Park in Western Australia. This 29-exposure composite was captured in September 2015 and has made repeat APOD appearances since then.

The park contains thousands of weathered limestone pillars. Some of the tallest pinnacles reach heights over 10 feet above the yellow sand base. The different types of formations include ones which are much taller than they are wide and resemble columns—suggesting the name of Pinnacles—while others are only 3 feet or so in height and width resembling short tombstones. A cross-bedding structure is observed in many of the structures where the angle of deposited sand changed suddenly due to changes in prevailing winds during formation of the limestone beds.

Pinnacles with tops similar to mushrooms were created where a harder carbonate deposit has formed over a softer limestone layer below it. As a result, the lower layers weather and erode at a faster rate than the top layer leaving behind more material at the top of the pinnacle. Did you notice the light 'pyramid'? That is zodiacal light adding a nice touch to the overall visual product.