{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.673","julian_year":2026.673,"time":"2026-09-03T21:23:05.812Z","years_from_j2000":26.673,"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-49147","name":"HD 49147","class":"a0iiie_white_giant","category":"star","object_type":"A0IIIe white giant","mag":5.66,"mag_band":"V","abs_mag":-0.435,"abs_mag_band":"V","distance_ly":539.9939574827943,"distance_method":"parallax","ra_deg":101.66257499999999,"dec_deg":-10.10736,"epoch_ra_deg":101.980356,"epoch_dec_deg":-10.135736,"epoch_moved_arcsec":0.288,"pm_ra_mas_yr":-10.77,"pm_dec_mas_yr":0.77,"orbits":null,"semi_major_axis_km":null,"periapsis_km":null,"mass_kg":null,"mass_msun":null,"constellation":"Monoceros","discovered":null,"featured":false,"url":"https://spacecatalog.org/object/hd-49147","radius_km":null,"radius_kind":null,"data_quality":null,"description":null,"properties":{"age_years":299700170,"mass_solar":3.136,"radius_solar":4.601,"spectral_type":"A0IIIe","color_index_bv":-0.048,"luminosity_solar":130.01695780332912,"radial_velocity_km_s":17,"spectral_type_source":"SIMBAD (2018A&A...609A.108S, quality C)","surface_gravity_log_g":3.576,"surface_temperature_k":9933,"proper_motion_ra_mas_yr":-10.77,"proper_motion_dec_mas_yr":0.77,"stellar_parameters_method":"Gaia DR3 model fit (GSP-Phot, FLAME; RUWE ≤ 1.4) — low confidence: above 7,500 K GSP-Phot's temperature and extinction are degenerate","bolometric_luminosity_solar":162.6403},"designations":[{"catalog":"HD","designation":"HD 49147"},{"catalog":"HIP","designation":"HIP 32474"},{"catalog":"HR","designation":"HR 2502"}],"source":{"id":"hyg","name":"HYG Database v4.1","url":"https://github.com/astronexus/HYG-Database","license":"CC-BY-SA-4.0"},"updated_at":"2026-09-02T19:50:56.720Z","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."}