| Discovery[1] | |
|---|---|
| Discovered by | C. Shoemaker E. Shoemaker |
| Discovery site | Palomar Obs. |
| Discovery date | 20 August 1982 |
| Designations | |
| (3225) Hoag | |
Named after | Arthur Hoag[1] (American astronomer) |
| 1982 QQ · 1977 RN7 1977 SY2 | |
| main-belt · (inner)[2] Hungaria[1][3][4] · background[5] | |
| Orbital characteristics[2] | |
| Epoch 23 March 2018 (JD 2458200.5) | |
| Uncertainty parameter 0 | |
| Observation arc | 39.52yr (14,435 d) |
| Aphelion | 1.9791AU |
| Perihelion | 1.7805 AU |
| 1.8798 AU | |
| Eccentricity | 0.0528 |
| 2.58 yr (941 d) | |
| 296.92° | |
| 0° 22m 56.64s / day | |
| Inclination | 25.060° |
| 188.86° | |
| 138.10° | |
| Earth MOID | 0.7960 AU (310.1038LD) |
| Physical characteristics | |
| 5.06±0.92 km[6] 5.56 km(calculated)[3] 5.921±0.053 km[7] 6.24±0.06 km[8] | |
| 2.3717±0.0002 h[9][a] 2.372±0.0004 h[10] 2.3722±0.0005 h[11] 2.3728±0.0005 h[12] 2.373±0.002 h[13] 2.3737±0.0004 h[14] 2.496±0.001 h[15] | |
| 0.25[4]0.287±0.038[8] 0.3(assumed)[3] 0.31±0.11[6] 0.3203±0.0510[7] | |
| S/L(S3OS2)[16] E/S(assumed)[3] | |
| 13.00[7][8] 13.135±0.001(R)[10] 13.17±0.80[17] 13.2[2][3] 13.4[4] 13.46[6] | |
3225 Hoag, provisional designation1982 QQ, is a dynamical Hungariaasteroid from the innermost regions of theasteroid belt, approximately 5.5 kilometers (3.4 miles) in diameter. It was discovered on 20 August 1982, by American astronomer coupleCarolyn andEugene Shoemaker at thePalomar Observatory in California.[1] The stonyS/L-type asteroid has a shortrotation period of 2.37 hours.[3] It was named for American astronomerArthur Hoag.[1]
Hoag is a member of the dynamicalHungaria group,[1][3][4] that forms the innermost dense concentration of asteroids in theSolar System.[3] However, it is not a member of theHungaria family (003), located within the dynamical group, but an asteroid of thebackground population.[5]
It orbits the Sun in theinnermost asteroid belt at a distance of 1.8–2.0 AU once every 2 years and 7 months (941 days;semi-major axis of 1.88 AU). Its orbit has aneccentricity of 0.05 and aninclination of 25° with respect to theecliptic.[2] The body'sobservation arc begins with its second of two observations,1977 RN7 and1977 SY2, taken atCrimea–Nauchnij September 1977, almost 5 years prior to its official discovery observation at Palomar.[1]
TheSmall Solar System Objects Spectroscopic Survey (S3OS2) characterizedHoag as a stonyS-type and uncommonL-type asteroid in the Tholen- and SMASS-like taxonomy, respectively.[16]
Several rotationallightcurves ofHoag have been obtained fromphotometric observations since 2007.[9][10][11][12][13][14][15] Best-rated lightcurve by American astronomerBrian Warner at hisPalmer Divide Observatory in Colorado, gave a well-definedrotation period of 2.3717 hours with a brightness amplitude of 0.12magnitude (U=3).[3][9][a]
In 2010, Warner also modeled a lightcurve using the data from his various photometric observations. It gave a concurring sidereal period of 2.37219 hours, as well as twospin axes at (45.0°, 45.0°) and (225.0°, 45.0°) inecliptic coordinates (λ, β).[11]
According to the survey carried out by theNEOWISE mission of NASA'sWide-field Infrared Survey Explorer,Hoag measures between 5.06 and 6.24 kilometers in diameter and its surface has analbedo between 0.28 and 0.32.[6][7][8] TheCollaborative Asteroid Lightcurve Link assumes an albedo of 0.3 – a compromise figure between a stony (0.20) and an E-type (0.40) Hungarian asteroid – and calculates a diameter of 5.56 kilometers based on anabsolute magnitude of 13.2.[3]
Thisminor planet was named after American astronomerArthur Hoag (1921–1999), a former director of theLowell Observatory, known for his photometric research, the development of astronomical sites and instruments, and investigations ofquasars.[1] In 1950, he discovered a type ofring galaxy known asHoag's Object. The official naming citation was published by theMinor Planet Center on 27 December 1985 (M.P.C. 10311).[18]
