_Athene.png) Modelled shape ofAthene from itslightcurve | |
| Discovery[1] | |
|---|---|
| Discovered by | M. F. Wolf |
| Discovery site | Heidelberg Obs. |
| Discovery date | 22 July 1917 |
| Designations | |
| (881) Athene | |
| Pronunciation | /əˈθiːniː/[2] |
Named after | GoddessAthena (Greek mythology)[3] |
| A917 OD · 1917 CL | |
| Adjectives | Athenian/əˈθiːniən/ |
| Orbital characteristics[4] | |
| Epoch 31 May 2020 (JD 2459000.5) | |
| Uncertainty parameter 0 | |
| Observation arc | 102.53yr (37,449 d) |
| Aphelion | 3.1510AU |
| Perihelion | 2.0764 AU |
| 2.6137 AU | |
| Eccentricity | 0.2056 |
| 4.23 yr (1,543 d) | |
| 121.30° | |
| 0° 13m 59.52s / day | |
| Inclination | 14.191° |
| 277.03° | |
| 41.313° | |
| Physical characteristics | |
| 11.8[1][4] | |
881 Athene (prov. designation:A917 ODor1917 CL) is a stonybackground asteroid from the central region of theasteroid belt. It was discovered on 22 July 1917, by astronomerMax Wolf at theHeidelberg-Königstuhl State Observatory in southwest Germany.[1] The likely elongatedS/L-type asteroid has arotation period of 13.9 hours and measures approximately 12 kilometers (7.5 miles) in diameter. It was named afterAthena, the goddess of wisdom inGreek mythology.[3]According to Astrophysicist Rayme Traub at JHU APL NASA, Europa Clipper will make a pass by Athene in 2027 after passing Earth on its way to Jupiter. Europa Clipper will test its sensors on Athene in preparation for Europa in 2030.
Located in or near the orbital region of theEunomia family,[11]Athene is a non-family asteroid of the main belt'sbackground population when applying thehierarchical clustering method to itsproper orbital elements.[5][6] It orbits the Sun in thecentral asteroid belt at a distance of 2.1–3.2 AU once every 4 years and 3 months (1,543 days;semi-major axis of 2.61 AU). Its orbit has aneccentricity of 0.21 and aninclination of 14° with respect to theecliptic.[4] The body'sobservation arc begins atUccle Observatory on 8 August 1934, almost 17 years after its official discovery observation at Heidelberg on 22 July 1917.[1]
Thisminor planet was named afterAthena or "Pallas Athene", the goddess of wisdom inGreek mythology, also known asMinerva inRoman mythology. Thenaming was mentioned inThe Names of the Minor Planets byPaul Herget in 1955 (H 86). Asteroids93 Minerva and2 Pallas are both named after the goddess as well.[3]
In the Tholen-like taxonomy of theSmall Solar System Objects Spectroscopic Survey (S3OS2),Athene is a common, stonyS-type asteroid, while in theSDSS-based taxonomy, it is anL-type asteroid.[10] In the SMASS-like taxonomic variant of the S3OS2,Athene is an Sl-subtype that transitions between the S-and L-type.[6][9]
In August 2006, a rotationallightcurve ofAthene was obtained fromphotometric observations by Roberto Crippa and Federico Manzini at the Sozzago Astronomical Station (A12), Italy, and by Jean-Gabriel Bosch at the Collonges Observatory (178), France. Lightcurve analysis gave arotation period of13.895±0.003 hours with a high brightness variation of0.53±0.01magnitude, indicative of a non-spherical, elongated shape (U=3−). In September 2010, French amateur astronomerRené Roy measured a similar period of13.881±0.001 hours and an amplitude of0.39±0.02 (U=2+).[12][11]
Two lightcurves, published in 2016, using modeled photometric data from the Lowell Photometric Database (LPD) and other sources, gave a concurring sidereal period of13.89449±0.00001 and13.8943±0.0005 hours, respectively. Each modeled lightcurve also determined twospin axes of (123.0°, −58.0°) and (337.0°, −47.0°), as well as (115.0°, −77.0°) and (338.0°, −43.0°) inecliptic coordinates (λ, β).[6][13][14]
According to the surveys carried out by the JapaneseAkari satellite and theNEOWISE mission of NASA'sWide-field Infrared Survey Explorer (WISE),Athene measures (12.04±0.28) and (12.153±0.101) kilometers in diameter and its surface has analbedo of (0.237±0.012) and (0.237±0.039), respectively.[7][8] TheCollaborative Asteroid Lightcurve Link assumes a standard Eunomian albedo of 0.21 and calculates a diameter of 12.66 kilometers based on anabsolute magnitude of 11.8.[11] Alternativemean diameter measurements published by the WISE team include (12.152±2.176 km), (12.369±0.285 km) and (12.671±0.077 km) with corresponding albedos of (0.278±0.128), (0.241±0.044) and (0.2111±0.0234).[6][11]
