Phaenna Dorsum
What Phaenna Dorsum is
Phaenna Dorsum is a dorsum — a ridge — on Mars, 164 km across, centred at 53.8° S, 43.3° W in the Argyre quadrangle. It is the 453rd largest named feature on Mars and the 27th largest of its class there.
Where the name comes from
One of the Graces. The International Astronomical Union approved the name in 1991, under the theme it applies to every dorsum on Mars. Of the 36 features of this class catalogued on Mars, the naming categories run Greek (20), Latin (13), Egypt (1), Syria (1).
What it would take to settle Phaenna Dorsum
Mars scores 26.6 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 53.8° S, 43.3° W.
What this spot has going for it is temperature — about -71 °C mean at this latitude. What works against it is ground — mixed ground — a rim, a floor and slopes between them.
Computed from Phaenna 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 Mars (radiation geometry, earth link). Gravity, pressure, delta-v and distance from the Sun are the same everywhere on Mars 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 dorsum features on Mars
All 36 dorsa on Mars — mapped together, with the naming theme and the size distribution.