mcp-stargazing

Instructions

Implementation Reference

• src/functions/celestial/impl.py:98-121 (handler)

  MCP tool handler for 'get_visible_planets'. Processes location/time inputs, delegates to core calculation via asyncio.to_thread, and formats the response with format_response.
  @mcp.tool() async def get_visible_planets( lon: float, lat: float, time: str, time_zone: str ) -> Dict[str, Any]: """Get a list of solar system planets currently visible (above horizon). Args: lon: Observer longitude in degrees lat: Observer latitude in degrees time: Observation time string "YYYY-MM-DD HH:MM:SS" time_zone: IANA timezone string Returns: Dict with keys "data", "_meta". "data" is a list of planet dicts (name, altitude, azimuth). """ location, time_info = process_location_and_time(lon, lat, time, time_zone) # Note: Function name collision with imported function 'get_visible_planets' # Use the imported function from src.celestial from src.celestial import get_visible_planets as calc_visible_planets planets = await asyncio.to_thread(calc_visible_planets, location, time_info) return format_response(planets)
• src/celestial.py:171-210 (helper)

  Core implementation that iterates over solar system planets, computes their alt/az using astropy.get_body and AltAz frame, and collects those with altitude > 0.
  def get_visible_planets( observer_location: EarthLocation, time: Union[Time, datetime] ) -> list[Dict[str, Any]]: """ Get a list of planets currently above the horizon. Args: observer_location: Observer's EarthLocation. time: Observation time. Returns: List of dicts containing planet name, altitude, azimuth, and magnitude (if available). """ # Convert local time to UTC if input is datetime if isinstance(time, datetime): if time.tzinfo is None: raise ValueError("Input datetime must be timezone-aware for local time.") time = Time(time.astimezone(pytz.UTC)) planets = ["mercury", "venus", "mars", "jupiter", "saturn", "uranus", "neptune"] visible_planets = [] for planet in planets: # Get coordinates obj_coord = get_body(planet, time) altaz_frame = AltAz(obstime=time, location=observer_location) altaz = obj_coord.transform_to(altaz_frame) # Check if above horizon if altaz.alt.deg > 0: visible_planets.append({ "name": planet.capitalize(), "altitude": float(altaz.alt.deg), "azimuth": float(altaz.az.deg), "constellation": None # Placeholder for future implementation }) return visible_planets