astronomy-mcp-server

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• tools: 7 tools scanned
• metadata: scanned
• packages: 2 checked

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Tools (7)

• astronomy_get_sky_position

  Compute the apparent topocentric position of one solar-system body (sun, moon, mercury through neptune, pluto) or a named bright star for an observer location and instant. Returns equatorial (RA/Dec), refraction-corrected horizontal (altitude/azimuth), and ecliptic coordinates, plus distance, apparent magnitude, angular diameter, phase angle, illuminated fraction, angular distance from the Sun, and the constellation it falls in. For a solar-system body it also returns that body card — classification, mean radius, naked-eye visibility — the same values served at astronomy://body/{body}, so a client without resource support does not need a second surface to reach them; a catalog star has no card and the field is absent. Positions are parallax- and aberration-corrected for the given observer; default elevation is 0 m and the default time is now. Supply `star` (e.g. "Sirius", "Polaris") instead of `body` to target a catalog star; `body` is ignored when `star` is set. Pass an IANA `timezone

• astronomy_get_rise_set

  Compute rise, set, and culmination (transit) times for a body at an observer location, plus the maximum altitude at culmination. For the Sun, also returns the three twilight pairs (civil −6°, nautical −12°, astronomical −18°) so a single call answers "when does the sun set and when is it truly dark." Each pair covers the night after the cycle's set — dusk that evening, dawn the next morning — so the dawn listed beside a sunrise is the following day's; for the dawn before a sunrise, read the previous cycle or start a day earlier. Searches forward from `start` (default today) and returns the next `count` cycles (default 1). When the body is already above the horizon at `start`, the first cycle is the interval in progress: its `set` is the imminent one and its `rise` is null, since that rise precedes the search — so a set is never reported earlier than the rise beside it. Circumpolar or never-rises situations are reported as null rise/set fields with an explanatory note rather than an err

• astronomy_get_moon_phase

  Report the Moon phase for an instant: illuminated fraction, phase name, synodic age in days since the new moon, phase longitude (the Moon–Sun ecliptic-longitude difference, 180° at full), and the next four quarter phases (new, first quarter, full, last quarter) with timestamps. Answers "what is the moon phase tonight" and "when is the next full moon" in one call without iteration. The time defaults to now; pass an IANA `timezone` to also receive observer-local timestamps. The phase is geocentric — no observer location is needed.

• astronomy_find_events

  Search forward from a start time for the next occurrences of one sky-event class, selected by the `event` enum: solar_eclipse, lunar_eclipse, equinox, solstice, moon_quarter, opposition, conjunction, max_elongation, or perigee_apogee. Both eclipse classes take an optional observer (latitude and longitude together). solar_eclipse without one returns global eclipses — kind, peak time, obscuration, and for a total or annular eclipse the latitude/longitude where it is greatest; with one it returns only eclipses visible from that point, with local contact times, `local_visible`, and the Sun's altitude at each contact. lunar_eclipse returns geocentric contact times, the same instants everywhere on Earth; an observer adds `local_visible` and the Moon's altitude at each contact. Every other class is geocentric and ignores a location. The body-relative events (opposition, conjunction, max_elongation, perigee_apogee) require a `body`: opposition applies to the superior planets (mars through plut

• astronomy_list_visible

  The one-call "what is up right now" answer. For an observer location and instant, iterate every naked-eye solar-system body (and, with include_stars, the bundled bright stars), compute altitude and azimuth, keep those above the horizon, rank them brightest-and-highest first, and attach a plain-language visibility note to each, along with its angular distance from the Sun. The whole sky is gated by the Sun's altitude into daylight / civil / nautical / astronomical twilight / dark, returned alongside the list, and each note says when daylight, civil twilight, or the Sun's glare hides or dims that body. `time` is a single evaluation instant, not a window — for "tonight" pass a time after astronomical dusk (use astronomy_get_rise_set on the sun to find it). Default elevation 0 m; use min_altitude to skip objects grazing the horizon. This server does not geocode — resolve coordinates upstream first; pass an IANA timezone for observer-local times on each body.

• astronomy_get_ephemeris

  Fetch a time-series ephemeris for a small body (asteroid or comet) or spacecraft from JPL Horizons — RA/Dec, distance, and apparent magnitude over a span, optionally with observer-relative altitude/azimuth. This covers objects the in-process major-body set cannot. The designation is passed to Horizons verbatim, so it must be in a form Horizons resolves to a single record: a numbered asteroid takes a trailing-semicolon record lookup (e.g. "433;" for Eros, "1;" for Ceres), and a periodic comet takes the DES + closest-apparition form (e.g. "DES=1P;CAP" for Halley). Spacecraft take their negative SPK-ID. Anything else goes through the Horizons name search: a bare name matching nothing (e.g. "433 Eros") or several records (e.g. "1P/Halley") is rejected, but one matching a single object succeeds even when that object is not the one meant — "Eros" resolves to Kerberos, a moon of Pluto — so compare `target_name`, the object Horizons resolved, with the one intended. `start` and `stop` are ISO 8

• astronomy_get_satellite_passes

  Predict visible passes of a satellite (e.g. the ISS, NORAD 25544) over an observer in the next `days`. Identify the satellite by exactly one of `norad_id` or `name` — supplying both, or neither, is rejected. A few well-known common names resolve directly to their catalog numbers, ignoring case: ISS or International Space Station (25544), Hubble, Hubble Space Telescope, or HST (20580), and Tiangong, CSS, or Chinese Space Station (48274). Any other `name` is matched as a case-insensitive substring of CelesTrak's catalog names, so it resolves only when it picks out a single object: a broader query comes back with the matching objects and their catalog numbers to choose from. Either way the result echoes the query that resolved it as `resolved_from_name`. Fetches the object's current GP element set from CelesTrak, propagates it with SGP4 in-process, and returns each pass's rise, peak, and set times with azimuths and the peak elevation. Only passes that are naked-eye-plausible are returned