| Discovery[1] | |
|---|---|
| Discovered by | S. J. Bus |
| Discovery site | Siding Spring Obs. |
| Discovery date | 2 March 1981 |
| Designations | |
| (4432) McGraw-Hill | |
Named after | McGraw-Hill Telescope[1] (atKitt Peak, Arizona) |
| 1981 ER22 · 1964 TV | |
| main-belt[1][2] · (inner)[3] background[4] | |
| Orbital characteristics[2] | |
| Epoch 23 March 2018 (JD 2458200.5) | |
| Uncertainty parameter 0 | |
| Observation arc | 53.54yr (19,555 d) |
| Aphelion | 2.8975AU |
| Perihelion | 1.8747 AU |
| 2.3861 AU | |
| Eccentricity | 0.2143 |
| 3.69 yr (1,346 d) | |
| 188.28° | |
| 0° 16m 2.64s / day | |
| Inclination | 0.4616° |
| 115.15° | |
| 246.30° | |
| Physical characteristics | |
| 3.042±0.643 km[5][6] 3.43 km(derived)[3] | |
| inconclusive[3][7] | |
| 0.20(assumed)[3] 0.254±0.224[5][6] | |
| S(assumed)[3] | |
| 14.5[1][2] 14.69[3][6][7] | |
4432 McGraw-Hill, provisional designation1981 ER22, is a backgroundasteroid from the inner regions of theasteroid belt, approximately 3 kilometers (2 miles) in diameter. It was discovered on 2 March 1981, by American astronomerSchelte Bus at theSiding Spring Observatory in Australia. The likelyS-type asteroid was named for theMcGraw-Hill Telescope located atKitt Peak, Arizona.[1]
McGraw-Hill is a non-family asteroid from the main belt'sbackground population.[4] It orbits the Sun in theinner asteroid belt at a distance of 1.9–2.9 AU once every 3 years and 8 months (1,346 days;semi-major axis of 2.39 AU). Its orbit has aneccentricity of 0.21 and aninclination of 0° with respect to theecliptic.[2]
The asteroid was first observed as1964 TV atPurple Mountain Observatory in October 1964. The body'sobservation arc begins with aprecovery taken atPalomar Observatory in February 1977, or four years prior to its official discovery observation at Siding Spring.[1]
McGraw-Hill is an assumed, stonyS-type asteroid,[3] in agreement with the albedo(see below) obtained by theWide-field Infrared Survey Explorer (WISE).
During the Small Main-Belt Asteroid Lightcurve Survey,McGraw-Hill has been observedphotometrically. The observations gave a small brightness variation of 0.06magnitude but resulted in no useful rotationallightcurve (U=n.a.).[7] As of 2018, the body'srotation period,pole and shape remain unknown.[2]
According to the survey carried out by theNEOWISE mission of NASA's WISE telescope,McGraw-Hill measures 3.042 kilometers in diameter and its surface has analbedo of 0.254,[5][6] while theCollaborative Asteroid Lightcurve Link assumes a standard albedo for a stony asteroid of 0.20 and derives a diameter of 3.43 kilometers based on anabsolute magnitude of 14.69.[3]
Thisminor planet was named after the 1.3-meterMcGraw-Hill Telescope located at theMDM Observatory at theKitt Peak National Observatory site in Arizona, United States.[1] The official naming citation was published by theMinor Planet Center on 18 February 1992 (M.P.C. 19697).[8]
