The Australia Telescope Compact Array (ATCA), at the Narrabri Observatory, is an array of six 22-m antennas used for radio astronomy. It is located about 25 km west of the town of Narrabri in rural NSW (about 500 km north-west of Sydney). It is operated by the Australia Telescope National Facility, a division of CSIRO.

The Australia Telesccope operates in the radio region of the spectrum. it essentially uses high technology to combine the signals from a number of dishes or elements, to obtain the performance of a single theoretical dish a number of kilometers in diameter. The Compact Array , located at the Paul Wild Observatory, near Narrabri, is the heart of the telescope. It consists of six 22 metre dishes, five of which are spaced along a 3km track with the sixth a further 3km to the west. A seventh dish, forming part of the long baseline array, is located a few kilometeres west of Coonabarabran. The Tidbinbilla Tracking Station and Parkes Radio Telescope are also equipped to form part of the long baseline array.

A visit to the Australia Telescope Compact Array website will show what is happening at the telescope including up to the minute observing updates from the "ACTA Live" page.

Also on the ATNF site at Narrabri is the Sydney University Stellar Interferometer (SUSI), an optical interferometer used to measure diameters of stars and separation of close binary stars. Although not normally open to visitors, SUSI is described in the display at the visitor's centre.

The visitor's centre at Narrabri is well located. being adjacent to the array's track, good views of the dishes are available. There is an excellent display and video tape presentation which explains the concepts behind the telescope and radio astronomy in general.

Hours: 8am to 4pm daily (not staffed weekends, except school holidays)

Cost: No charge to visit the centre. Booking are appreciated for groups.

Contact: Tim Kennedy (02) 6790-4070

Website: http://www.narrabri.atnf.csiro.au/

Back to Observatories

Getting there,  See below.

Driving from Narrabri township to the observatory

When travelling from the town to the observatory, there are two paths to follow at first, depending on whether you are approaching from the town centre or from the southern outskirts of the town.

When travelling from the south: You reach the outskirts of Narrabri (either from Coonabarabran or Gunnedah) in a large roundabout. Continue on towards the township proper crossing a railway track and then arriving at another large roundabout. Here you turn left (away from Narrabri) and follow the sign to the "Australia Telescope". Another few hundred metres later, veer right (keeping the water tower on your left). Soon afterwards you pass the Wilga Hotel on your left.
When travelling from the town centre: Leaving the town centre heading south towards Sydney or Coonabarabran, you cross the main river flow (Narrabri Creek) and then the old dry riverbed of the Namoi River. Shortly afterwards follow the signs to "Australia Telescope" turning right (Ugoa St), left around the Narrabri Lake (Walowa St), and then right again at the Wilga Hotel (Goobar St - which turns into Yarrie Lake Road).
From the Wilga Hotel, keep going west, past the large Cargill cottonseed oil factory on your left, crossing a railway track and the usually dry Bohena Ck. About 20km from town there is a sign directing you right to the "Australia Telescope". Follow this tarred road 2km, and you are there. The Observers' Lodge is the first building that you come to, on your left.
Warning! There are often kangaroos and sheep grazing on the site: please drive carefully, particularly approaching dawn and dusk. Headlights dazzle kangaroos (and other animals), but they tend to react less suicidally if you `dip' the headlights when approaching them. During and after rain there are a series of causeways/floodways which can become quite deep. Please slow down and cross with care.