Ryujin Dorsum
What Ryujin Dorsum is
Ryujin Dorsum is a dorsum — a ridge — on Ryugu, 3.2 km across, centred at 0.0° N, 180.0° W. It is the 1st largest named feature on Ryugu and the 1st largest of its class there.
Where the name comes from
âDragon godâ, sea ruler in Japanese fairy tale, father of princess Otohime, master of the undersea Ryugu Palace where fisherman Urashima Taro was a guest. The International Astronomical Union approved the name in 2018.
What it would take to settle Ryujin Dorsum
Ryugu scores 58.1 as a world. That number is the same for every square metre of it — but sunlight, water, radiation and the ground under your feet are not. This is the same question asked at 0.0° N, 180.0° W.
What this spot has going for it is sunlight — 100% of the sunlight the sunniest latitude on Ryugu gets. What works against it is water — same as everywhere else on this world.
Computed from Ryujin Dorsum's catalogued latitude, longitude and feature class — 74% of the model's weight had a basis here, and 2 axes were dropped as not applicable to Ryugu (radiation geometry, earth link). Gravity, pressure, delta-v and distance from the Sun are the same everywhere on Ryugu and are already counted in the world's own index, not again here.
What this cannot see: elevation. Slope, local shadowing and the polar “peaks of eternal light” — ridge tops near the poles of a barely tilted world that catch sun almost continuously while a crater floor kilometres away never does — need a terrain model this does not have. Where a real mission targets a pole, that is usually why.