Nightbase — Where every night has a mission

Get Moon

Get the Moon's phase and position for a UTC time and observer location. Returns illuminated fraction, phase name, waxing/waning, RA/Dec, distance, libration, magnitude, and — when lat/lon are supplied — the local altitude and azimuth.

List Described Objects

List the catalog designations that have a rich Nightbase description in a given language. Useful for discovering which objects get_object_description can return content for.

Get Object Description

Get Nightbase's rich editorial description for an object — prose description, observing tips, history and fun facts — in a requested language with English fallback. Available for a curated subset of objects (see list_described_objects). Returns found=false when no description exists.

Search Catalog

Search the Nightbase catalog with optional filters: free-text (name/designation/alternate name), object type, constellation (3-letter abbreviation), brightness cutoff, and source catalog. Returns up to 50 matching objects with id, designation, type, constellation, magnitude and coordinates. Use find_object instead when you already know the exact object.

Score Visibility

Score how easy a deep-sky object or star is to SEE through a given telescope from a given sky. Returns a 0-10 visibility score: 10 = springs into direct vision, 5 = at the limit of comfortable averted vision for an experienced observer, 0 = impossible. This is Nightbase's authoritative engine. The model is DELIBERATELY calibrated pessimistic — do not inflate, round up, or second-guess a low score; a low score means the target really is hard or impossible with that setup. Scores are condition-ind

Find Object

Resolve a free-text astronomical object name to its Nightbase catalog entry. Accepts designations ("M81", "NGC 3031"), common names ("Bode's Galaxy", "Vega"), or alternate names. Use this to get an object's id, type, coordinates and magnitude before scoring it, or to obtain its canonical Nightbase detail-page URL. Returns found=false when nothing matches.

List Bright Comets

List currently active comets brighter than a magnitude cutoff, from Nightbase's curated feed. When observer lat/lon are supplied, includes each comet's best altitude over the coming night and whether it rises above the horizon. Returns an empty list when no comets meet the cutoff.

Get Planet Position

Get the sky position of a planet (or the Sun) for a UTC time and observer location. Returns RA/Dec, Earth distance (AU), apparent magnitude, elongation from the Sun, and — when lat/lon are supplied — the local altitude and azimuth.

Whats Up Tonight

Suggest the best targets to observe from a location with a given telescope during a session window. Ranks objects by Nightbase's (deliberately pessimistic) visibility score and their altitude in the window, biases toward easier targets and any special events, and includes dynamic solar-system bodies. The session start auto-slides to nautical dusk if it would begin before dark. Returns a ranked target list with coordinates, magnitude, best altitude and visibility score, plus moon/weather summarie