Network typical sky
—mag/arcsec²
Median of every site's typical night
The whole reserve
The network at a glance
Sites online
—sensors
Darkest site
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Bortle 1–3 sites
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Sites reaching genuinely dark-sky classes
Nights recorded
—site-nights
Across the whole network
Brightest site
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Where we watch
The sentinel map
Every sensor in the reserve on real geography — watch the Murray wind through the network. Darker dots mean darker skies. Click a sentinel to visit its site.
Darker site
Brighter site
Map data © OpenStreetMap contributors © CARTO
Sensor network
Visit a sentinel
Twenty monitoring sites across 3,200 km² of protected night. Each has its own dashboard of nightly readings, trends and insights.
The long view
The reserve through the seasons
Each dot is the network median across all reporting sites for one night — the moon's monthly rhythm written into the sky itself.
Insights from the network
Understand the numbers
How dark is dark?
Magnitudes per square arc-second
Our sensors measure the brightness of the night sky in magnitudes per square arc-second (mag/arcsec²) — the standard unit used by astronomers. It runs backwards from what you might expect: bigger number = darker sky.
The scale is logarithmic: every 5 magnitudes is a 100× difference in light. So a sky at 22 mag/arcsec² isn't a little darker than an 18 mag/arcsec² city sky — it's about 40 times darker.
The Bortle scale
The Bortle scale describes what you can actually see, from Class 1 (the darkest skies on Earth) to Class 9 (inner-city). The badges show how many of our sites reach each class.
About
The River Murray International Dark Sky Reserve
Stretching along the River Murray in South Australia, the reserve is one of only a handful of accredited International Dark Sky Reserves in the world — and one of the darkest. Its core at Meldanda, near Cambrai, records skies that regularly reach Bortle Class 1–2: nights so dark the Milky Way casts a shadow.
River Murray Sky Watch turns the reserve's scientific monitoring into something everyone can explore. Unihedron Sky Quality Meters measure the glow of the night sky every minute, while infrared cloud sensors track conditions overhead. Together they tell the story of a landscape where the night is still truly wild.
Reference data collected by RMIDSR volunteers at Meldanda using Unihedron SQM-LE and SQM-LU-DL sensors and an environmental cloud sensor. The other 19 sites are currently simulated from the Meldanda reference record to demonstrate the full network experience ahead of installation. Sky brightness readings are zenith measurements in mag/arcsec²; timestamps in charts are local time (UTC+10:30).