Madang & the North Coast · Papua New Guinea · Seamount · Pelagic & blue water
Planet Rock
Grey reef sharks on patrol and hammerheads in the deeper water
Planet Rock is Madang's best-known dive: an offshore seamount that climbs from 600 m of water to within 5 m of the surface. Ocean currents running through Astrolabe Bay sweep over its top and draw schooling pelagic fish and sharks, which is why divers make the run out whenever conditions allow.
Where it is and how deep
5.2278° S, 145.7917° EApproximate position — the dashed circle shows where the site lies; your operator's briefing has the mooring.
The dive
The top of the mount sits at about 4 to 5 m, and the current sweeps around and across this apex, carrying schools of predatory fish with it. The sides fall away to the base at 36 m, while the sea around the mount plummets past 600 m.
An hour is enough for a complete circuit of the rock. Schools of barracuda and trevally hang off the walls with mackerel, tuna, rainbow runners, batfish and oceanic triggerfish. Grey reef sharks patrol the site, and scalloped hammerheads show in the deeper water, so divers keep watching the blue throughout the circuit.
Marine life and season
- Reef sharks
- Hammerheads
- Barracuda
- Trevally & jacks
- Tuna
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Good | Good | Good | Good | Fair | Fair | Fair | Fair | Fair | Fair | Good | Good |
Season follows Madang & the North Coast: Diving runs all year; May to October brings the heaviest rain and run-off that clouds the sites nearest the mainland.
Know before you go
- Strong ocean currents and the offshore position mean the seamount cannot always be dived; boats go only when conditions allow.
Dive videos
Diving at Planet Rock, Madang, Papua New Guinea · ychiko2008 on YouTube
Questions divers ask
Can Planet Rock be dived on any day of a Madang trip?+
Not always. The strong currents through Astrolabe Bay and the site's position 3 km offshore close it on some days, so it is best treated as a dive to take when the conditions open up.
Sources
- Planet Rock — DivePlanit
- Planet Rock — Niugini Dive Adventures
- Dive Sites — Niugini Dive Adventures
- OpenStreetMap — OpenStreetMap
More dive sites in Madang & the North Coast
Wreck
Machine guns still in the nose, midships and tail of a 1943 bomber
Wall
Hooded epaulette sharks tucked under ledges on a current-fed wall
Wreck
Office items and big refrigerators still sitting in the holds
Wreck
The remains of a truck still lying in the cargo hold
Channel & pass
A wall of big-eye trevally closing around divers on the turning tide
Wall
Silvertip sharks on a sheer wall a few metres from shore
Similar dives elsewhere
An isolated seamount that pulls in barracuda and trevally schools
A submerged island from 12 m to 40, with current and big fish
Twin peaks at 8 m over walls falling 80 m, in current that feeds the fish
Where Malapascua's thresher sharks moved in 2022, at 12–22 m