Lacus Tenebrarum
What Lacus Tenebrarum is
Lacus Tenebrarum is a lacus — a small dark plain — on The Moon, 85 km across, centred at 86.7° S, 87.7° W in the Amundsen quadrangle. It is the 495th largest named feature on The Moon and the 14th largest of its class there.
Where the name comes from
âLake of Darkness.â The International Astronomical Union approved the name in 2025, under the theme it applies to every lacus on The Moon.
What it would take to settle Lacus Tenebrarum
The Moon scores 29.1 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 86.7° S, 87.7° W.
What this spot has going for it is water — inside the polar zone where The Moon keeps its ice. What works against it is sunlight — 6% of the sunlight the sunniest latitude on The Moon gets.
Computed from Lacus Tenebrarum's catalogued latitude, longitude and feature class — 84% of the model's weight had a basis here, and one axis was dropped as not applicable to The Moon (radiation geometry). Gravity, pressure, delta-v and distance from the Sun are the same everywhere on The Moon 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.
What is next to it
The largest lacus features on The Moon
All 21 lacus on The Moon — mapped together, with the naming theme and the size distribution.