{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.819","julian_year":2026.819,"time":"2026-10-27T01:52:20.602Z","years_from_j2000":26.819,"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-11909","name":"8 ι Ari","class":"g8iii_yellow_giant","category":"star","object_type":"G8III yellow giant","mag":5.09,"mag_band":"V","abs_mag":-0.924,"abs_mag_band":"V","distance_ly":520.1855021949232,"distance_method":"parallax","ra_deg":29.33772,"dec_deg":17.817532,"epoch_ra_deg":29.706846,"epoch_dec_deg":17.949086,"epoch_moved_arcsec":1.118,"pm_ra_mas_yr":34.28,"pm_dec_mas_yr":-23.71,"position_epoch_jyear":null,"orbits":null,"semi_major_axis_km":null,"periapsis_km":null,"mass_kg":null,"mass_msun":null,"constellation":"Aries","discovered":null,"featured":false,"url":"https://spacecatalog.org/object/hd-11909","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":"01574+1749","companions":[{"measured":1933,"magnitude":6.4,"components":null,"discoverer_code":"OCC 182","separation_arcsec":0.1,"position_angle_deg":-1}],"spectral_type":"G8III","color_index_bv":0.921,"luminosity_solar":203.98583002685626,"metallicity_fe_h":-0.1,"radial_velocity_km_s":-5,"spectral_type_source":"SIMBAD (1990A&AS...85.1069S, quality C)","surface_gravity_log_g":2.6,"surface_temperature_k":5025,"metallicity_fe_h_source":"One spectroscopic determination, compiled from the literature (PASTEL, Soubiran+ 2016)","proper_motion_ra_mas_yr":34.28,"proper_motion_dec_mas_yr":-23.71,"stellar_parameters_method":"Spectroscopic determinations compiled from the literature (PASTEL, Soubiran+ 2016)"},"designations":[{"catalog":"Bayer/Flamsteed","designation":"8 Iota Ari"},{"catalog":"HD","designation":"HD 11909"},{"catalog":"HIP","designation":"HIP 9110"},{"catalog":"HR","designation":"HR 563"}],"updated_at":"2026-10-01T09:42:28.932Z","citation":{"plain":"SpaceCatalog. 8 ι Ari [catalogue entry]. Data release DR1 (2026-08-21). https://spacecatalog.org/object/hd-11909","bibtex":"@misc{spacecatalog_hd-11909,\n  author       = {{SpaceCatalog}},\n  title        = {{8 ι Ari}},\n  howpublished = {SpaceCatalog, data release DR1 (2026-08-21)},\n  year         = {2026},\n  url          = {https://spacecatalog.org/object/hd-11909},\n  note         = {Catalogue entry, data release DR1 (2026-08-21). Values from HYG Database v4.1.}\n}","url":"https://spacecatalog.org/object/hd-11909","release":"DR1","doi":null},"references":[{"bibcode":"1990A&AS...85.1069S","ads_url":"https://ui.adsabs.harvard.edu/abs/1990A%26AS...85.1069S/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."}