Aegir, also Saturn XXXVI (provisional designation S/2004 S 10), is a natural satellite of Saturn. Its discovery was announced by Scott S. Sheppard, David C. Jewitt, Jan Kleyna, and Brian G. Marsden on May 4, 2005, from observations taken between December 12, 2004, and March 11, 2005.
| Discovery | |
|---|---|
| Discovered by | S. Sheppard, D. Jewitt, J. Kleyna, and B. Marsden |
| Discovery date | May 4, 2005 |
| Designations | |
Designation | Saturn XXXVI |
| Pronunciation | /ˈaɪjɪər, ˈæɡɪər/ etc. |
Named after | Ægir |
| S/2004 S 10 | |
| Orbital characteristics[1] | |
| 20735000 km | |
| Eccentricity | 0.252 |
| 1025.908 d | |
| Inclination | 166.7° |
| Satellite of | Saturn |
| Group | Norse group |
| Physical characteristics[2] | |
| 4 km | |
| Albedo | 0.06 (assumed) |
Spectral type | B–R = 1.30 ± 0.06[3] |
| 24.4 | |
| 15.5 | |
Aegir is about 4 kilometres in diameter, and orbits Saturn at an average distance of 19,618 Mm in 1025.908 days, at an inclination of 167° to the ecliptic (140° to Saturn's equator), in a retrograde direction and with an eccentricity of 0.237.
Name
editThe moon was named in April 2007 after Ægir, a giant from Norse mythology, the personification of tranquil seas, the one who soothes storms away. He is a son of Fornjót, and brother of Logi (fire, flame) and Kári (wind). The exoplanet Epsilon Eridani b (AEgir) was also named after this figure in 2015.[4]
The name may be pronounced various ways. /ˈaɪjɪər/ (with the 'g' pronounced as a y-sound) approximates modern Norwegian and Icelandic. /ˈæɡɪər/ (with a hard 'g') approximates what the Old Norse may have sounded like, while the Latinized/spelling pronunciations /ˈiːdʒɪər/, /ˈɛdʒɪər/ and /ˈeɪdʒɪər/ are also found.[5][6][7]
References
edit- ^ Ma, Yuehua; et al. (2010), "On the Origin of Retrograde Orbit Satellites around Saturn and Jupiter", Icy Bodies of the Solar System, Proceedings of the International Astronomical Union, IAU Symposium, vol. 263, pp. 157–160, Bibcode:2010IAUS..263..157M, doi:10.1017/S1743921310001687.
- ^ Denk, Tilmann; Mottola, Stefano; Tosi, Frederico; Bottke, William F.; Hamilton, Douglas P. (2018). "The Irregular Satellites of Saturn" (PDF). In Schenk, P.M.; Clark, R.N.; Howett, C.J.A.; Verbiscer, A.J.; Waite, J.H. (eds.). Enceladus and the Icy Moons of Saturn. Space Science Series. Vol. 322. Tucson, AZ: The University of Arizona Press. pp. 409–434. Bibcode:2018eims.book..409D. doi:10.2458/azu_uapress_9780816537075-ch020. ISBN 9780816537075.
- ^ Graykowski, Ariel; Jewitt, David (2018-04-05). "Colors and Shapes of the Irregular Planetary Satellites". The Astronomical Journal. 155 (4): 184. arXiv:1803.01907. doi:10.3847/1538-3881/aab49b. ISSN 1538-3881.
- ^ "Final Results of NameExoWorlds Public Vote Released". International Astronomical Union. 15 December 2015. Retrieved 2017-09-25.
- ^ Merriam-Webster's Encyclopedia of Literature (1995)
- ^ "Aegir". Dictionary.com Unabridged (Online). n.d.
- ^ Harold Stanford (1922), The Standard Reference Work: For the Home, School and Library
External links
edit- T. Denk's Aegir website
- Institute for Astronomy Saturn Satellite Data
- D. Jewitt's New Satellites of Saturn page
- IAUC 8523: New Satellites of Saturn May 4, 2005 (discovery)
- MPEC 2005-J13: Twelve New Satellites of Saturn May 3, 2005 (discovery and ephemeris)
- IAUC 8826: Satellites of Jupiter and Saturn April 5, 2007 (naming the moon)