{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.663","julian_year":2026.663,"time":"2026-08-31T00:30:51.106Z","years_from_j2000":26.663,"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":"merga","name":"Merga","class":"f6ivs_yellow_white_subgiant","category":"star","object_type":"F6IVs yellow-white subgiant","mag":5.76,"mag_band":"V","abs_mag":2.309,"abs_mag_band":"V","distance_ly":159.80227420058475,"distance_method":"parallax","ra_deg":222.327795,"dec_deg":46.116205,"epoch_ra_deg":222.56879,"epoch_dec_deg":46.003783,"epoch_moved_arcsec":2.071,"pm_ra_mas_yr":-7.35,"pm_dec_mas_yr":-77.32,"orbits":null,"semi_major_axis_km":null,"periapsis_km":null,"mass_kg":null,"mass_msun":null,"constellation":"Boötes","discovered":null,"featured":false,"url":"https://spacecatalog.org/object/merga","radius_km":null,"radius_kind":null,"data_quality":null,"description":null,"properties":{"age_years":2095849500,"mass_solar":1.594,"radius_solar":2.609,"spectral_type":"F6IVs","uncertainties":{"metallicity_fe_h":[0.044,0.044]},"color_index_bv":0.482,"luminosity_solar":10.384844550082734,"metallicity_fe_h":0.08,"radial_velocity_km_s":-5,"spectral_type_source":"SIMBAD (2001AJ....121.2148G, quality C)","surface_gravity_log_g":3.822,"surface_temperature_k":6249,"metallicity_fe_h_source":"Median of 3 spectroscopic determinations in 4 papers, compiled from the literature (PASTEL, Soubiran+ 2016); the error bar is the scatter between them","proper_motion_ra_mas_yr":-7.35,"proper_motion_dec_mas_yr":-77.32,"stellar_parameters_method":"Gaia DR3 model fit (GSP-Phot, FLAME; RUWE ≤ 1.4)","bolometric_luminosity_solar":9.4833},"designations":[{"catalog":"Bayer/Flamsteed","designation":"38 Boo"},{"catalog":"Common name","designation":"Merga"},{"catalog":"HD","designation":"HD 130945"},{"catalog":"HIP","designation":"HIP 72487"},{"catalog":"HR","designation":"HR 5533"}],"source":{"id":"hyg","name":"HYG Database v4.1","url":"https://github.com/astronexus/HYG-Database","license":"CC-BY-SA-4.0"},"updated_at":"2026-08-30T09:56:50.739Z","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."}