The USNO algorithm produces illumination accurate within fractions of a percent for any given moment. Daily display rounds to whole percentages because that's the precision the user-facing question demands. For tighter astrophotography planning, expose a per-hour illumination column via a list mapping if needed; the data is already in the source row.

Yes. The phase name and illumination are global, but the visual orientation differs in the southern hemisphere. A hemisphere flag in the city row drives icon orientation through a selector mapping, so the glyph the visitor sees matches the way the moon actually looks from their latitude.

Yes. Add a meteor_shower_slugs column to the city row that lists which showers fall during the dark-moon windows in the next month. A list mapping renders a card grid linking to /meteor-showers/{slug}/, so visitors pivot from lunar interference planning to specific shower nights in one click.

A flags column lists special-event tags per row when the upcoming month carries a blue moon, supermoon, or eclipse. A selector mapping promotes any non-empty flag into a banner above the hero block, so the page surfaces the unusual event without disrupting the standard layout.

Yes. The two page groups can share the same city catalog and the same lat/long/timezone fields. Run the lunar algorithm against the same input and let the moon-phase page group cross-link to /sun-position/{slug}/ in a side card. Both pages stay in sync without manual coordination.

Yes. Each page emits an Article JSON-LD block with the current phase, illumination, and city in the headline. For specific events like a full moon, the schema switches to Event with startDate and endDate covering the visibility window. A category column drives the schema selection at render time.

The algorithm runs against absolute Julian dates, not calendar conventions, so leap years and timezone shifts are handled correctly. The DST transition is the only city-level concern, and the timezone field on each city row captures that correctly. The base page renders identically every day of the year.

Yes. A print-stylesheet variant of the base page renders the upcoming month's daily phase calendar as a single-page printable layout. The data is the same; only the CSS differs. Visitors print a moon calendar for their fridge straight from the city URL.