| Discovery[1] | |
|---|---|
| Discovered by | G. van Biesbroeck |
| Discovery site | Yerkes Obs. |
| Discovery date | 2 December 1923 |
| Designations | |
| (1024) Hale | |
Named after | George Ellery Hale[2] (American astronomer) |
| A923 YO13 | |
| main-belt[1][3] · (outer)[4] background[5] | |
| Orbital characteristics[3] | |
| Epoch 23 March 2018 (JD 2458200.5) | |
| Uncertainty parameter 0 | |
| Observation arc | 89.22yr (32,587 d) |
| Aphelion | 3.5095AU |
| Perihelion | 2.2230 AU |
| 2.8663 AU | |
| Eccentricity | 0.2244 |
| 4.85 yr (1,772 d) | |
| 173.74° | |
| 0° 12m 11.16s / day | |
| Inclination | 16.090° |
| 58.856° | |
| 307.94° | |
| Physical characteristics | |
| 28.46±6.70 km[6] 41.28 km(derived)[4] 43.274±0.148 km[7] 45.964±17.12 km[8] 47.33±8.98 km[9] 47.674±0.893 km[10] 48.18±0.78 km[11] 51.37±15.55 km[12] | |
| 16.0±0.1 h[13] | |
| 0.0260±0.0240[8] 0.027±0.047[12] 0.0289±0.0057[10] 0.03±0.02[9] 0.044±0.002[11] 0.045±0.007[7] 0.0496(derived)[4] 0.10±0.04[6] | |
| SMASS =Ch[3] · C[14] C(SDSS-MFB)[4] | |
| 10.60[11] · 10.70[3][9] 10.78[8][14] · 10.8[4][10] 10.83[6] · 11.00[12] | |
1024 Hale, provisional designationA923 YO13, is a carbonaceous backgroundasteroid from the outer regions of theasteroid belt, approximately 45 kilometers (28 miles) in diameter. The asteroid was discovered on 2 December 1923, by Belgian–American astronomerGeorge Van Biesbroeck at theYerkes Observatory in Wisconsin, United States.[1] It was named for American astronomerGeorge Ellery Hale.[2] The darkC-type asteroid may have arotation period of 16 hours.[4]
Hale is a non-family asteroid from the main belt'sbackground population.[5] It orbits the Sun in theouter asteroid belt at a distance of 2.2–3.5 AU once every 4 years and 10 months (1,772 days;semi-major axis of 2.87 AU). Its orbit has aneccentricity of 0.22 and aninclination of 16° with respect to theecliptic.[3] The body'sobservation arc begins at Yerkes Observatory with its first recorded observation in December 1928, or five years after its official discovery observation.[1]
Hale has been characterized as a carbonaceousC-type asteroid by Pan-STARRS' photometric survey and by theSDSS-MFB (Masi Foglia Binzel).[4] In theSMASS classification it is a "hydrated" Ch-subtype.[3]
In January 2013, a first rotationallightcurve ofHale was obtained from photometric observations by Michael S. Alkema at the Elephant Head Observatory (G35) in Arizona, United States. Analysis of the fragmentary lightcurve gave arotation period of 16.0 hours with a brightness amplitude of 0.10magnitude (U=1+).[13] As of 2018, no secure period has been obtained.[4]
According to the surveys carried out by the JapaneseAkari satellite and theNEOWISE mission of NASA'sWide-field Infrared Survey Explorer,Hale measures between 28.46 and 51.37 kilometers in diameter and its surface has analbedo between 0.0260 and 0.10.[6][7][8][9][10][11][12]
TheCollaborative Asteroid Lightcurve Link derives an albedo of 0.0496 and a diameter of 41.28 kilometers based on anabsolute magnitude of 10.8.[4]
Thisminor planet was named afterGeorge Ellery Hale (1868–1938), a prolific American astronomer and pioneer of a new generation of large aperture telescopes, namely the60-inch Hale and the 100-inchHooker telescope atMount Wilson Observatory, as well as the200-inch Hale telescope atPalomar Observatory. He founded the discoveringYerkes and Mount Wilson observatories and was their first director. Hale also foundedThe Astrophysical Journal and invented thespectroheliograph, which allowed to take monochromatic images of the Sun. The official naming citation was mentioned inThe Names of the Minor Planets byPaul Herget in 1955 (H 98).[2]
