The listed coordinates for this geocache is the Sydney offices of the Anglo-Australian Observatory (AAO).
The AAO has its telescopes at Siding Spring near Coonabarabran in central west NSW. The largest is the Anglo-Australian Telescope has a 4 metre diameter mirror, and was one of the largest in the southern hemisphere when it was commissioned in 1974.
The Astronomical Society of NSW meets at nearby Dence Park. If you're interested in astronomy, it's worth heading to one or two of their meetings.
To determine the coordinates of the geocache you must 'decode' the images below.
You can check your answers for this puzzle on Geochecker.com.
Geocaching NSW aims to enhance and improve the activity of geocaching in New South Wales. Visit the association website at www.geocachingnsw.asn.au.