{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.817","julian_year":2026.817,"time":"2026-10-26T13:22:43.227Z","years_from_j2000":26.817,"frame":"date","applied":"Proper motion, then precession and nutation. The catalogued position is carried along the great circle the object's own published motion puts it on, at a constant velocity, from the epoch that position was measured at, 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. The motion runs from position_epoch_jyear where the upstream publishes one — a timed pulsar's position belongs to the year it was timed — and from J2000 where it does not. 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-102510","name":"4 Vir","class":"a1v_white_main_sequence_star","category":"star","object_type":"A1V white main-sequence star","mag":5.31,"mag_band":"V","abs_mag":1.449,"abs_mag_band":"V","distance_ly":192.99194719704053,"distance_method":"parallax","ra_deg":176.97876,"dec_deg":8.245895,"epoch_ra_deg":177.325315,"epoch_dec_deg":8.096128,"epoch_moved_arcsec":1.464,"pm_ra_mas_yr":-53.24,"pm_dec_mas_yr":12.14,"position_epoch_jyear":null,"orbits":null,"semi_major_axis_km":null,"periapsis_km":null,"mass_kg":null,"mass_msun":null,"constellation":"Virgo","discovered":null,"featured":false,"url":"https://spacecatalog.org/object/hd-102510","source":{"id":"hyg","name":"HYG Database v4.1","url":"https://github.com/astronexus/HYG-Database","license":"CC-BY-SA-4.0","attribution":"HYG Database v4.1, Astronexus (github.com/astronexus/HYG-Database). Fields derived from it stay under CC BY-SA 4.0.","commercial_use":"allowed"},"radius_km":null,"radius_kind":null,"data_quality":null,"description":null,"properties":{"wds_id":"11479+0815","age_years":366188620,"companions":[{"measured":2006,"magnitude":null,"components":"Aa,Ab","discoverer_code":"CHR 134","separation_arcsec":0.4,"position_angle_deg":85},{"measured":2006,"magnitude":13.2,"components":"AD","discoverer_code":"RBR   2","separation_arcsec":3,"position_angle_deg":293},{"measured":2015,"magnitude":11.59,"components":"AB","discoverer_code":"SHJ 131","separation_arcsec":148.4,"position_angle_deg":358},{"measured":2015,"magnitude":9.94,"components":"AC","discoverer_code":"SHJ 131","separation_arcsec":482.1,"position_angle_deg":322}],"mass_solar":2.148,"radius_solar":2.007,"spectral_type":"A1V","color_index_bv":0.038,"luminosity_solar":22.92978591824822,"radial_velocity_km_s":-1,"spectral_type_source":"SIMBAD (2001A&A...373..625P, quality C)","surface_gravity_log_g":4.099,"surface_temperature_k":9285,"proper_motion_ra_mas_yr":-53.24,"proper_motion_dec_mas_yr":12.14,"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":25.7774},"designations":[{"catalog":"Bayer/Flamsteed","designation":"4 Vir"},{"catalog":"HD","designation":"HD 102510"},{"catalog":"HIP","designation":"HIP 57562"},{"catalog":"HR","designation":"HR 4528"}],"updated_at":"2026-10-01T09:42:28.932Z","citation":{"plain":"SpaceCatalog. 4 Vir [catalogue entry]. Data release DR1 (2026-08-21). https://spacecatalog.org/object/hd-102510","bibtex":"@misc{spacecatalog_hd-102510,\n  author       = {{SpaceCatalog}},\n  title        = {{4 Vir}},\n  howpublished = {SpaceCatalog, data release DR1 (2026-08-21)},\n  year         = {2026},\n  url          = {https://spacecatalog.org/object/hd-102510},\n  note         = {Catalogue entry, data release DR1 (2026-08-21). Values from HYG Database v4.1.}\n}","url":"https://spacecatalog.org/object/hd-102510","release":"DR1","doi":null},"references":[{"bibcode":"2001A&A...373..625P","ads_url":"https://ui.adsabs.harvard.edu/abs/2001A%26A...373..625P/abstract","quantity":"properties.spectral_type_source"}],"attribution":"Data from SpaceCatalog.org. Each record names its upstream in `source`, with that producer's terms in `source.license`, the acknowledgement it asks for in `source.attribution`, and whether its terms allow commercial use in `source.commercial_use`; those terms govern the record, and citing SpaceCatalog does not discharge them."}