{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.670","julian_year":2026.67,"time":"2026-09-02T16:55:17.217Z","years_from_j2000":26.67,"frame":"date","applied":"Proper motion, then precession and nutation. The catalogued J2000 position is carried along the great circle the object's own published motion puts it on, at a constant velocity, and the result is referred to the true equator and equinox of this instant. Those are separate things: the motion moves the object, and the rotation turns the grid under it by about fifty arcseconds a year, with nutation adding up to another seventeen.","excluded":"Parallax, the radial-velocity perspective term, aberration and refraction; each is below the accuracy of the catalogued positions themselves. An object with no published proper motion comes back where the catalogue has it rather than at a fabricated zero, and says so with a null pm_ra_mas_yr. A body with no fixed position is not propagated at all — its place comes from an ephemeris, which is what /api/v1/visible answers with."},"slug":"hd-216397","name":"15 Lac","class":"m1iii_red_giant","category":"star","object_type":"M1III red giant","mag":4.95,"mag_band":"V","abs_mag":-0.043,"abs_mag_band":"V","distance_ly":325.1808439909926,"distance_method":"parallax","ra_deg":343.008375,"dec_deg":43.312417,"epoch_ra_deg":343.310496,"epoch_dec_deg":43.454976,"epoch_moved_arcsec":2.973,"pm_ra_mas_yr":109.36,"pm_dec_mas_yr":21.54,"orbits":null,"semi_major_axis_km":null,"periapsis_km":null,"mass_kg":null,"mass_msun":null,"constellation":"Lacerta","discovered":null,"featured":false,"url":"https://spacecatalog.org/object/hd-216397","radius_km":null,"radius_kind":null,"data_quality":null,"description":null,"properties":{"wds_id":"22520+4319","companions":[{"measured":2014,"magnitude":11.9,"components":"AB","discoverer_code":"BU  451","separation_arcsec":23.6,"position_angle_deg":159},{"measured":2014,"magnitude":12.5,"components":"AE","discoverer_code":"FOX 270","separation_arcsec":58.7,"position_angle_deg":347},{"measured":2014,"magnitude":12.57,"components":"AC","discoverer_code":"BU  451","separation_arcsec":106.4,"position_angle_deg":305},{"measured":2014,"magnitude":13.59,"components":"AD","discoverer_code":"BU  451","separation_arcsec":140.9,"position_angle_deg":230}],"spectral_type":"M1III","color_index_bv":1.559,"luminosity_solar":90.61498022319977,"radial_velocity_km_s":-17,"spectral_type_source":"SIMBAD (1985ApJS...59...95A, quality C)","proper_motion_ra_mas_yr":109.36,"proper_motion_dec_mas_yr":21.54},"designations":[{"catalog":"Bayer/Flamsteed","designation":"15 Lac"},{"catalog":"HD","designation":"HD 216397"},{"catalog":"HIP","designation":"HIP 112917"},{"catalog":"HR","designation":"HR 8699"}],"source":{"id":"hyg","name":"HYG Database v4.1","url":"https://github.com/astronexus/HYG-Database","license":"CC-BY-SA-4.0"},"updated_at":"2026-09-01T22:58:55.274Z","attribution":"Data from SpaceCatalog.org. Individual records carry their source and license in `source`; attribution is required for CC-BY and CC-BY-SA rows."}