Heliopolis Facula
What Heliopolis Facula is
Heliopolis Facula is a facula — a bright spot — on Ganymede, 50 km across, centred at 18.5° N, 147.0° W. It is the 145th largest named feature on Ganymede and the 13th largest of its class there.
Where the name comes from
Sacred Egyptian city of the sun. The International Astronomical Union approved the name in 1997, under the theme it applies to every facula on Ganymede.
What it would take to settle Heliopolis 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 18.5° N, 147.0° 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 -158 °C mean at this latitude.
Computed from Heliopolis 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.