An interactive globe of Jupiter's ocean moon, textured with the USGS Voyager 1/2 + Galileo SSI controlled global mosaic at 500 m/px source resolution. The 129 IAU-adopted names are selectable — the lineae that cross the whole surface, the chaos terrains, the dark maculae and the few impact craters; the research feed is retrieved at run time.
The sphere is rendered in Three.js at Europa's mean radius, 1560.8 km (IAU 2015), scaled to scene units. The base layer is the USGS controlled global mosaic, assembled from Voyager 1 and 2 ISS and Galileo SSI frames at a 500 m/px source scale and delivered here at 8192 × 4096, about 1.2 km per texel at the equator. The surface it shows is water ice, among the youngest in the Solar System: a crater count of order forty across the whole moon implies a mean age of tens of millions of years, which is why the lineae rather than impact basins carry the map. Relief is offered but has no measured source — no global digital elevation model of Europa exists, and stereo coverage reaches only a few per cent of the surface — so with relief enabled the page derives a bump map from mosaic luminance, which encodes illumination and albedo rather than height. Textures are read from Data/worlds/europa/.
Named features are the complete IAU set drawn from the USGS Gazetteer of Planetary Nomenclature via Data/worlds/europa/features.json: 129 records — 49 lineae, 41 craters, the nine chaos terrains including Conamara, the eight regiones, the dark maculae, and the two large ringed features Tyre and Callanish. A centre point is an official coordinate and not a mapped outline; for a linea a thousand kilometres long, the point marks the catalogue centre only. The research panel queries body_server.py at /api/europa/latest for current Europa literature (NASA ADS, with OpenAlex and arXiv as fallbacks); a per-feature endpoint returns recent papers on the selected feature. Absent a server, the seed research.json and ADS search links are substituted. Engine, server and schema are shared with the Mercury, Venus and Moon globes.
Markers use the east-positive convention of the IAU. The longitude registration of the mosaic was measured rather than assumed. Two independent tests agree: the thirteen dark maculae and chaoses sit 11 DN below the equatorial band mean while the 35 craters sit 4.9 DN above it, and the leading hemisphere centred on 90°W reads 39.6 DN brighter than the trailing hemisphere centred on 90°E — the well-established asymmetry produced by sulphur implantation from the Io torus onto the trailing side. Both put the image left edge at 0°E, so lonOffsetDeg is 180. Pwyll (25.2°S, 88.6°E), whose ray system is the brightest thing on the moon, and Thera Macula (46.7°S, 178.8°E) are the visual registration checks.
Europa is highlighted in cyan on a live map of the uniquely-named solar-system bodies — planets, dwarf planets, named asteroids and comets — with the interstellar objects and escaping spacecraft, each at its current position and linked to its source.
body_server.py