| angular_dist =
| long_periastron = (linear drift) {{val|445.475|0.007}}°/day
| time_periastron =
| semi-amplitude =
| surface_area =
| volume =
| mass =
| surface_grav =
| albedo = < 0.15
| single_temperature =
}}Aegaeon ({{IPAc-en|iː|ˈ|dʒ|iː|ən}} {{respell|ee|JEE|ən}}; or as Greek Αιγαίων), also {{nowrap|Saturn LIII}} (provisional designation {{nowrap|S/2008 S 1}}), is a natural satellite of Saturn. It is thought to be similarly smooth as Methone.[3] It orbits between Janus and Mimas within Saturn's G Ring.
Discovery and naming
Images of Aegaeon were taken by Cassini on 15 August 2008, and its discovery was announced on 3 March 2009 by Carolyn Porco of the Cassini Imaging Science Team using the provisional designation {{nowrap|S/2008 S 1}}.[4]
Aegaeon was named after Ægæon, one of the hekatonkheires, on 5 May 2009.[5]
Orbit
Aegaeon orbits within the bright segment of Saturn's G Ring, and is probably a major source of the ring.[6] Debris knocked off Aegaeon forms a bright arc near the inner edge, which in turn spreads to form the rest of the ring. Aegaeon orbits in a 7:6 corotation eccentricity resonance with Mimas,[ which causes an approximately 4-year oscillation of about 4 km in its semi-major axis, and a corresponding oscillation of a few degrees in its mean longitude. It orbits Saturn at an average distance of 167,500 km in 0.80812 days, at an inclination of 0.001° to Saturn's equator, with an eccentricity of 0.0002.[4]]
{{clear left}} Physical characteristics
Aegaeon is the smallest known moon of Saturn and has a highly elongated shape, measuring {{convert|1.4|x|0.5|x|0.4|km|mi|abbr=on}} in size.[7] Measurements of its mass, based on its interaction with the dust particles that make up the G ring arc the moon is embedded in, suggest a density similar to that of water ice.[8] Aegaeon has the lowest albedo, below 0.15, of any Saturnian moon inward of Titan.[8] This might be due to either darker meteoric material making up the dust in the G ring or due to Aegaeon having been disrupted, stripping away its ice-rich surface and leaving the rocky inner core behind.[8]
Exploration
The Cassini spacecraft has performed four flybys of Aegaeon closer than 20,000 km, though only one has occurred since it was discovered in 2008. The closest of these pre-discovery encounters took place on 5 September 2005 at a distance of 8,517 km.[9] An encounter on 27 January 2010 at a distance 13,306 km allowed Cassini to acquire its highest resolution images of Aegaeon to-date.[8] On 19 December 2015, Cassini was unable to acquire any images from a planned close flyby.
Other images
References
1. ^1 2 {{cite conference | first = P. C. | last = Thomas | authorlink = |display-authors=4 | author2 = Burns, J. A. |author3=Tiscareno, M. S. |author4=Hedman, M. M. |author5=Helfenstein, P. | title = Saturn's Mysterious Arc-Embedded Moons: Recycled Fluff? | booktitle = 44th Lunar and Planetary Science Conference | pages = 1598 | publisher = | date = 2013 | location = | url = http://www.lpi.usra.edu/meetings/lpsc2013/pdf/1598.pdf | accessdate = 2013-05-21 }}
2. ^(s) to append to the name)-->| discovered = {{start date|2009|3|3}}| discovery_method = Cassini Imaging Science Team| alt_names = | epoch = JD 2454467.00075444 TDB| semimajor = {{val|167493.665|0.004|u=km}} [{{cite journal|last1=Hedman|first1=M.M.|last2=Cooper|first2=N.J.|last3=Murray|first3=C.D.|last4=Beurle|first4=K.|last5=Evans|first5=M.W.|last6=Tiscareno|first6=M.S.|last7=Burns|first7=J.A.|title=Aegaeon (Saturn LIII), a G-ring object|journal=Icarus|date=May 2010|volume=207|issue=1|pages=433–447|doi=10.1016/j.icarus.2009.10.024|arxiv = 0911.0171 |bibcode = 2010Icar..207..433H }}]
3. ^{{cite web | last = Battersby | first = S. | authorlink = | title = Saturn's egg moon Methone is made of fluff | work = www.newscientist.com | publisher = New Scientist | date = 2013-05-17 | url = https://www.newscientist.com/article/dn23560-astrophile-saturns-egg-moon-methone-is-made-of-fluff.html | accessdate = 2013-05-21 | ref = {{sfnRef|Battersby, 2013}}}}
4. ^1 2 IAU Circular No. 9023
5. ^Jennifer Blue, [https://astrogeology.usgs.gov/news/nomenclature/saturnian-satellite-named-aegaeon Saturnian Satellite Named Aegaeon], USGS Astrogeology Hot Topics, 5 May 2009
6. ^Petite Moon, CICLOPS, 29 May 2009
7. ^{{cite journal|last1=Thomas|first1=P.C.|last2=Burns|first2=J.A.|last3=Hedman|first3=M.|last4=Helfenstein|first4=P.|last5=Morrison|first5=S.|last6=Tiscareno|first6=M.S.|last7=Veverka|first7=J.|title=The inner small satellites of Saturn: A variety of worlds|journal=Icarus|date=2013|volume=226|issue=1|pages=999–1019|doi=10.1016/j.icarus.2013.07.022|url=http://webpages.uidaho.edu/mhedman/papers_published/Thomas_littlesats_Icarus_2013.pdf|accessdate=2 December 2015|bibcode = 2013Icar..226..999T }}
8. ^1 2 3 {{cite conference|last1=Hedman|first1=M.M.|last2=Burns|first2=J.A.|last3=Thomas|first3=P.C.|last4=Tiscareno|first4=M.S.|last5=Evans|first5=M.W.|title=Physical Properties of the small moon Aegaeon (Saturn LIII)|journal=Icarus|date=2011|volume=6|conference=European Planetary Space Conference|url=http://yly-mac.gps.caltech.edu/A_DPS/dps%202011%20/a_dps%202011%20program%20+%20abstracts/pdf/EPSC-DPS2011-531-2.pdf|accessdate=2 December 2015 }}
9. ^Planetary Society Cassini Timeline
{{Spoken Wikipedia|Aegaeon_(moon).ogg|2010-01-16}}{{Moons of Saturn|state=uncollapsed}}{{Saturn}}{{DEFAULTSORT:Aegaeon}} 2 : Moons of Saturn|Astronomical objects discovered in 2009