{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.669","julian_year":2026.669,"time":"2026-09-02T09:25:33.077Z","years_from_j2000":26.669,"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-2925","name":"HD 2925","class":"g5iv_yellow_subgiant","category":"star","object_type":"G5IV yellow subgiant","mag":6.84,"mag_band":"V","abs_mag":1.145,"abs_mag_band":"V","distance_ly":449.2510562308196,"distance_method":"parallax","ra_deg":8.164755000000001,"dec_deg":23.193427,"epoch_ra_deg":8.518143,"epoch_dec_deg":23.341827,"epoch_moved_arcsec":3.49,"pm_ra_mas_yr":128.7,"pm_dec_mas_yr":23.64,"orbits":null,"semi_major_axis_km":null,"periapsis_km":null,"mass_kg":null,"mass_msun":null,"constellation":"Andromeda","discovered":null,"featured":false,"url":"https://spacecatalog.org/object/hd-2925","radius_km":null,"radius_kind":null,"data_quality":null,"description":null,"properties":{"wds_id":"00327+2312","age_years":502966300,"companions":[{"measured":2016,"magnitude":11.8,"components":"AB","discoverer_code":"BU 1310","separation_arcsec":3.8,"position_angle_deg":214},{"measured":2016,"magnitude":12.5,"components":"AC","discoverer_code":"BU 1310","separation_arcsec":28.1,"position_angle_deg":275},{"measured":2016,"magnitude":11.44,"components":"AD","discoverer_code":"BU 1310","separation_arcsec":93.6,"position_angle_deg":156}],"mass_solar":2.69,"radius_solar":8.964,"spectral_type":"G5IV","uncertainties":{"metallicity_fe_h":[0.017,0.017]},"color_index_bv":0.921,"luminosity_solar":30.338911841942704,"metallicity_fe_h":-0.53,"radial_velocity_km_s":-112,"spectral_type_source":"SIMBAD (1985ApJS...59...95A, quality C)","surface_gravity_log_g":2.905,"surface_temperature_k":5386,"metallicity_fe_h_source":"Median of 3 spectroscopic determinations in 6 papers, compiled from the literature (PASTEL, Soubiran+ 2016); the error bar is the scatter between them","proper_motion_ra_mas_yr":128.7,"proper_motion_dec_mas_yr":23.64,"stellar_parameters_method":"Gaia DR3 model fit (GSP-Phot, FLAME; RUWE ≤ 1.4)","bolometric_luminosity_solar":61.3825},"designations":[{"catalog":"HD","designation":"HD 2925"},{"catalog":"HIP","designation":"HIP 2573"}],"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."}