| Discovery[1] | |
|---|---|
| Discovered by | K. Reinmuth |
| Discovery site | Heidelberg Obs. |
| Discovery date | 26 January 1928 |
| Designations | |
| (1155) Aenna | |
Named after | Astronomische Nachrichten (Astronomy journal)[2] |
| 1928 BD · 1928 FU 1941 UZ · 1982 DR6 | |
| main-belt · (inner)[3] | |
| Orbital characteristics[1] | |
| Epoch 4 September 2017 (JD 2458000.5) | |
| Uncertainty parameter 0 | |
| Observation arc | 89.44 yr (32,668 days) |
| Aphelion | 2.8697AU |
| Perihelion | 2.0586 AU |
| 2.4641 AU | |
| Eccentricity | 0.1646 |
| 3.87yr (1,413 days) | |
| 351.13° | |
| 0° 15m 17.28s / day | |
| Inclination | 6.5935° |
| 39.122° | |
| 195.38° | |
| Physical characteristics | |
| Dimensions | 9.284±0.524 km[4] 11.36 km(derived)[3] 11.70±0.75 km[5] 14.093±0.105 km[6] |
| 8.07±0.04h[7] | |
| 0.2169(derived)[3] 0.2252±0.0212[6] 0.329±0.045[5] 0.356±0.040[4] | |
| SMASS = Xe[1] · X[3] | |
| 11.5[5][6] · 11.90[4] · 12.0[1][3] · 12.41±0.79[8] | |
1155 Aënna, provisional designation1928 BD, is anasteroid from the inner regions of theasteroid belt, approximately 11 kilometers in diameter. It was discovered on 26 January 1928, by German astronomerKarl Reinmuth atHeidelberg Observatory in southwest Germany.[9] It is named for the astronomy journalAstronomische Nachrichten.[2]
In theSMASS taxonomy, theX-type asteroid is classified as a Xe-type, an intermediary that transitions to the brightE-type asteroids. The spectra of a Xe-type contains an absorption feature near 0.49 μm, which is thought to be related with the presence of the iron sulfide mineraltroilite, typically found in lunar and Martian meteorites.[10]Aënna orbits the Sun in theinner main-belt at a distance of 2.1–2.9 AU once every 3 years and 10 months (1,413 days). Its orbit has aneccentricity of 0.16 and aninclination of 7° with respect to theecliptic.[1] The body'sobservation arc begins at Heidelberg with its official discovery observation in 1928.[9]
French amateur astronomerRené Roy obtained a rotationallightcurve ofAënna from photometric observations taken in December 2015. Lightcurve analysis gave arotation period of 8.07 hours with a brightness variation of 0.28magnitude (U=2+).[7]
According to the surveys carried out by the JapaneseAkari satellite and NASA'sWide-field Infrared Survey Explorer with its subsequentNEOWISE mission,Aënna measures between 9.28 and 14.09 kilometers in diameter, and its surface has analbedo between 0.225 and 0.356.[4][5][6] TheCollaborative Asteroid Lightcurve Link agrees best with Akari, and derives an albedo of 0.2169 with a diameter of 11.36 kilometers and anabsolute magnitude of 12.0.[3]
Thisminor planet was named afterAstronomische Nachrichten, one of the first internationaljournals in the field of astronomy. The constructed name "Aënna" contains the German pronunciation of the initials "A" and "N" followed by the mandatory feminine ending used for asteroids. The naming was proposed by theAstronomisches Rechen-Institut and mentioned inThe Names of the Minor Planets byPaul Herget in 1955 (H 108).[2]
