{"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":"2026-09-02T11:06:08.710Z","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-101298","name":"HD 101298","class":"o6_5iv_f_blue_subgiant","category":"star","object_type":"O6.5IV((f)) blue subgiant","mag":8.08,"mag_band":"V","abs_mag":null,"abs_mag_band":null,"distance_ly":null,"distance_method":null,"ra_deg":174.763665,"dec_deg":-63.429739,"epoch_ra_deg":175.076434,"epoch_dec_deg":-63.57842,"epoch_moved_arcsec":0.134,"pm_ra_mas_yr":-5.01,"pm_dec_mas_yr":0.01,"orbits":null,"semi_major_axis_km":null,"periapsis_km":null,"mass_kg":null,"mass_msun":null,"constellation":"Centaurus","discovered":null,"featured":false,"url":"https://spacecatalog.org/object/hd-101298","radius_km":null,"radius_kind":null,"data_quality":null,"description":null,"properties":{"wds_id":"11391-6326","companions":[{"measured":2015,"magnitude":10.16,"components":null,"discoverer_code":"RSS 268","separation_arcsec":56.3,"position_angle_deg":55}],"spectral_type":"O6.5IV((f))","color_index_bv":0.047,"radial_velocity_km_s":1,"spectral_type_source":"SIMBAD (2014ApJS..211...10S, quality C)","surface_gravity_log_g":4,"surface_temperature_k":33000,"proper_motion_ra_mas_yr":-5.01,"proper_motion_dec_mas_yr":0.01,"stellar_parameters_method":"Spectroscopic determinations compiled from the literature (PASTEL, Soubiran+ 2016)"},"designations":[{"catalog":"HD","designation":"HD 101298"},{"catalog":"HIP","designation":"HIP 56833"}],"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."}