{"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":"2026-09-02T04:52:08.639Z","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-157261","name":"HD 157261","class":"g5_yellow_star","category":"star","object_type":"G5 yellow star","mag":6.67,"mag_band":"V","abs_mag":2.225,"abs_mag_band":"V","distance_ly":252.63844708474542,"distance_method":"parallax","ra_deg":260.51721,"dec_deg":5.000817,"epoch_ra_deg":260.848543,"epoch_dec_deg":4.973865,"epoch_moved_arcsec":1.817,"pm_ra_mas_yr":22.78,"pm_dec_mas_yr":-64.22,"orbits":null,"semi_major_axis_km":null,"periapsis_km":null,"mass_kg":null,"mass_msun":null,"constellation":"Ophiuchus","discovered":null,"featured":false,"url":"https://spacecatalog.org/object/hd-157261","radius_km":null,"radius_kind":null,"data_quality":null,"description":null,"properties":{"wds_id":"17221+0500","age_years":1086558600,"companions":[{"measured":2016,"magnitude":11.6,"components":null,"discoverer_code":"BU  959","separation_arcsec":4,"position_angle_deg":257}],"mass_solar":2.052,"radius_solar":5.353,"spectral_type":"G5","uncertainties":{"metallicity_fe_h":[0.044,0.044]},"color_index_bv":0.927,"luminosity_solar":11.220184543019629,"metallicity_fe_h":-0.23,"radial_velocity_km_s":0,"spectral_type_source":"SIMBAD (1993yCat.3135....0C, quality E)","surface_gravity_log_g":3.199,"surface_temperature_k":5202,"metallicity_fe_h_source":"Median of 4 spectroscopic determinations in 3 papers, compiled from the literature (PASTEL, Soubiran+ 2016); the error bar is the scatter between them","proper_motion_ra_mas_yr":22.78,"proper_motion_dec_mas_yr":-64.22,"stellar_parameters_method":"Gaia DR3 model fit (GSP-Phot, FLAME; RUWE ≤ 1.4)","bolometric_luminosity_solar":19.1242},"designations":[{"catalog":"HD","designation":"HD 157261"},{"catalog":"HIP","designation":"HIP 84975"}],"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."}