_Hus.png) Shape model ofHus from itslightcurve | |
| Discovery[1] | |
|---|---|
| Discovered by | L. Kohoutek |
| Discovery site | Bergedorf Obs. |
| Discovery date | 26 October 1971 |
| Designations | |
| (1840) Hus | |
Named after | Jan Hus(early Reformer)[2] |
| 1971 UY · 1931 TS3 1935 NC · 1953 CG | |
| main-belt[1][3] · (outer)[4] Koronis[5][6] | |
| Orbital characteristics[3] | |
| Epoch 27 April 2019 (JD 2458600.5) | |
| Uncertainty parameter 0 | |
| Observation arc | 86.72yr (31,673 d) |
| Aphelion | 2.9646AU |
| Perihelion | 2.8731 AU |
| 2.9188 AU | |
| Eccentricity | 0.0157 |
| 4.99 yr (1,821 d) | |
| 174.31° | |
| 0° 11m 51.36s / day | |
| Inclination | 2.4077° |
| 40.525° | |
| 14.250° | |
| Physical characteristics | |
| 12.446±0.193 km[7][8] 12.592±0.123 km[9] | |
| 4.7483±0.0008 h[10] | |
| 0.2554±0.0232[9] 0.261±0.043[8] | |
| S(family-based)[11] | |
| 11.6[9] 11.7[1][3][4] | |
1840 Hus (prov. designation:1971 UY) is a stonyKoronis asteroid from the outer regions of theasteroid belt, approximately 12.5 kilometers (7.8 miles) in diameter. It was discovered on 26 October 1971, by Czech astronomerLuboš Kohoutek at theBergedorf Observatory in Hamburg, Germany.[1] TheS-type asteroid has arotation period of 4.8 hours and is likely elongated in shape.[4][10] It was later named after 15th-century theologianJan Hus.[2]
Hus is a core member of theKoronis family (605),[5][6] a very largeasteroid family of almost 6,000 known asteroids with nearly co-planar ecliptical orbits.[11] It orbits the Sun in theouter main-belt at a distance of 2.9–3.0 AU once every 5 years (1,821 days;semi-major axis of 2.92 AU). Its orbit has aneccentricity of 0.02 and aninclination of 2° with respect to theecliptic.[3]Hus was first observed as1931 TS3 at theLowell Observatory in October 1931. The body'sobservation arc begins with its observation as1953 CG at theGoethe Link Observatory in January 1953, more than 18 years prior to its official discovery observation at Hamburg.[1]
Thisminor planet was named after CzechJan Hus (1372–1415), a fifteenth century Bohemian theologian, rector of Charles University in Prague and forerunner of theProtestant Reformation. He was condemned to death by theCouncil of Constance and burned at the stake for his reformation ideas.[2] Jan Hus is also known asJohn Huss in the English speaking world. The officialnaming citation was published by theMinor Planet Center on 20 December 1974 (M.P.C. 3757).[12]
Based on the asteroid's membership to the Koronis family and its relatively highgeometric albedo determined by theWide-field Infrared Survey Explorer (WISE),Hus is very likely a stonyS-type asteroid.
In June 2006, a rotationallightcurve ofHus was obtained fromphotometric observations taken by Maurice Clark at the Chiro Observatory (320) in Western Australia. Lightcurve analysis gave arotation period of4.780±0.002 hours with a high brightness variation of 0.85magnitude (U=2-), strongly indicative of an elongated, non-spherical shape.[13] In March 2016, a synthetic lightcurve gave a similar period of4.749057±0.000001 hours, using sparse-in-time photometry data from the Lowell Photometric Database (U=n.a.).[14] More recent lightcurve analysis during observations of the 1840 Hus apparition in 2020, from theMITKoronis Family Asteroids Rotation Lightcurve Observing Program, gave a secure rotation period of4.7483±0.0008 hours.[10]
According to the survey carried out by NASA's WISE telescope with its subsequentNEOWISE mission,Hus measures 12.4 and 12.6 kilometers in diameter, and its surface has analbedo of 0.261 and 0.255, respectively.[7][8][9] Conversely, theCollaborative Asteroid Lightcurve Link assumes a standard albedo forcarbonaceous asteroids of 0.057, rather than one for astony body, as indicated by WISE/NEOWISE – and calculates therefore a twice as large diameter of 25.4 kilometers, as the lower the albedo, the larger the body's diameter for a constantabsolute magnitude.[4]
