Siwah Facula
What Siwah Facula is
Siwah Facula is a facula — a bright spot — on Ganymede, 220 km across, centred at 7.0° N, 143.0° W. It is the 55th largest named feature on Ganymede and the 9th largest of its class there.
Where the name comes from
Oasis oracle of Zeus-Ammon; visited by Alexander. The International Astronomical Union approved the name in 1985, under the theme it applies to every facula on Ganymede.
What it would take to settle Siwah Facula
Ganymede scores 55 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 7.0° N, 143.0° W.
What this spot has going for it is radiation geometry — under closed field lines, the shielded part of the only magnetosphere on any moon. What works against it is temperature — about -156 °C mean at this latitude.
Computed from Siwah Facula's catalogued latitude, longitude and feature class — 84% of the model's weight had a basis here, and 2 axes were dropped as not applicable to Ganymede (earth link, known ground). Gravity, pressure, delta-v and distance from the Sun are the same everywhere on Ganymede 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 facula features on Ganymede
All 13 faculae on Ganymede — mapped together, with the naming theme and the size distribution.