View source for Astronomy:Mab (moon)

{{Short description|Moon of Uranus}}
{{Infobox planet
| name               = Mab
| image              = Mabmoon.png
| caption            = 
| mpc_name           = Uranus XXVI
| alt_names          = 
| pronounced         = {{IPAc-en|ˈ|m|æ|b}}<ref>{{Dict.com|Mab}}</ref>
| adjectives         = Mabbian
| discoverer         = [[Biography:Mark R. Showalter|Mark R. Showalter]] and [[Biography:Jack J. Lissauer|Jack J. Lissauer]]
| discovered         = August 25, 2003
| semimajor          = 97,736 km
| orbital_speed      = 
| eccentricity       = 0.0025
| period             = 0.923 [[Day|d]]
| avg_speed = 7.70 km/s (calculated)
| inclination        = 0.1335° (to Uranus' equator)
| satellite_of       = [[Astronomy:Uranus|Uranus]]
| mean_radius =6–12&nbsp;km<ref name="Showalter Lissauer 2006" />
| surface_area       = ~1,900 km<sup>2</sup>
| volume             = ~8,000 km<sup>3</sup>
| mass               = ~1{{E-sp|15}} [[Kilogram|kg]]
| density            = ~1.3 [[Gram|g]]/cm<sup>3</sup>
| surface_grav       = ~0.0044 [[Physics:Acceleration|m/s<sup>2</sup>]]
| escape_velocity    = ~0.011 km/s
| rotation           = synchronous
| axial_tilt         = 0
| albedo             = 0.103 (assumed)
| magnitude          = 26<ref name="Sheppard urasatdata" />
| single_temperature = ~63 [[Kelvin|K]]
}}

'''Mab''', or '''Uranus XXVI''', is an inner satellite of [[Astronomy:Uranus|Uranus]]. It was discovered by [[Biography:Mark R. Showalter|Mark R. Showalter]] and [[Biography:Jack J. Lissauer|Jack J. Lissauer]] in 2003 using the [[Astronomy:Hubble Space Telescope|Hubble Space Telescope]].<ref name="IAUC 8209" /> It was named after Queen Mab, a fairy queen from English folklore who is mentioned in William Shakespeare's play ''Romeo and Juliet''.<ref name="Gazetteer" />

Because the moon is small and dark, it was not seen in the heavily scrutinized images taken by ''[[Astronomy:Voyager 2|Voyager 2]]'' during its Uranus flyby in 1986. However, it is brighter than another moon, [[Astronomy:Perdita (moon)|Perdita]], which was discovered from Voyager's photos in 1997. This led scientists to re-examine the old photos again, and the satellite was finally found in the images.<ref name="Showalter Lissauer 2006" />

The size of Mab is not known exactly. If it is as dark as [[Astronomy:Puck (moon)|Puck]], it is about 24&nbsp;km in diameter. On the other hand, if it is brightly coloured like the neighbouring moon [[Astronomy:Miranda (moon)|Miranda]], it would be even smaller than [[Astronomy:Cupid (moon)|Cupid]] and comparable to the smallest outer satellites.<ref name="Showalter Lissauer 2006" /> Infrared observation published in 2023 suggest that Mab could be most probably a 6-km body with a Miranda-like surface, rich in water ice. However a second possibility is that it could be a 12-km body with a Puck-like surface.<ref name="Molter2023">{{cite journal |doi=10.1016/j.icarus.2023.115697 |title=Keck near-infrared detections of Mab and Perdita |date=2023 |last1=Molter |first1=Edward M. |last2=De Pater |first2=Imke |last3=Moeckel |first3=Chris |journal=Icarus |volume=405 |page=115697 |s2cid=259885759 |arxiv=2307.13773 }}</ref>

Mab is heavily [[Astronomy:Perturbation|perturbed]]. The actual source for perturbation is still unclear, but is presumed to be one or more of the nearby orbiting moons.<ref name="Showalter Lissauer 2006" />

Mab orbits at the same distance from Uranus as the [[Astronomy:Rings of Uranus#μ (mu) and ν (nu) rings|μ ring]] (formerly known as R/2003 U 1), a dusty ring discovered around the same time as Mab. The moon is nearly the optimal size for dust production, since larger moons can recollect the escaping dust and smaller moons have too small surface areas for supplying the ring via ring particle or [[Astronomy:Meteoroid|meteoroid]] collisions.<ref name="Layton 2005" /> No rings associated with Perdita and Cupid have been found, probably because [[Astronomy:Belinda (moon)|Belinda]] limits the lifetimes of dust they generate.<ref name="Showalter Lissauer 2006" />

Following its discovery, Mab was given the temporary designation '''S/2003 U 1'''.<ref name="IAUC 8209" /> The moon is also designated '''Uranus XXVI'''.<ref name="Gazetteer" />

== See also ==
* [[Astronomy:Moons of Uranus|Moons of Uranus]]

== References ==
{{reflist
| refs =

<ref name="Showalter Lissauer 2006">
{{cite journal| doi = 10.1126/science.1122882| last1 = Showalter| first1 = Mark R.| last2 = Lissauer| first2 = Jack J.| date = 2006-02-17| title = The Second Ring-Moon System of Uranus: Discovery and Dynamics| journal = Science| volume = 311| issue = 5763| pages = 973–977| pmid = 16373533| bibcode = 2006Sci...311..973S| s2cid = 13240973}}
</ref>

<ref name="Sheppard urasatdata">
{{cite web
| last = Sheppard
| first = Scott S.
| title = Uranus' Known Satellites
| publisher = Carnegie Institution (Department of Terrestrial Magnetism)
| url = http://www.dtm.ciw.edu/users/sheppard/satellites/urasatdata.html
| access-date = 2011-11-02
}}
</ref>

<ref name="IAUC 8209">
{{cite journal
| last1 = Showalter
| first1 = Mark R.
| last2 = Lissauer
| first2 = Jack J.
| title = S/2003 U 1 and S/2003 U 2
| journal = IAU Circular
| volume = 8209
| date = September 25, 2003
| page = 1
| bibcode = 2003IAUC.8209....1S
| issn = 0081-0304
| url = http://www.cbat.eps.harvard.edu/iauc/08200/08209.html
| access-date = 2011-11-02
}}
</ref>

<ref name="Gazetteer">
{{cite web
| title = Planet and Satellite Names and Discoverers
| work = Gazetteer of Planetary Nomenclature
| publisher = USGS Astrogeology
| date = July 21, 2006
| url = http://planetarynames.wr.usgs.gov/Page/Planets
| access-date = 6 August 2006
}}
</ref>

<ref name="Layton 2005">
{{cite web|last=Layton |first=Laura |date=December 28, 2005 |title=Uranus' second ring-moon system |publisher=Astronomy Magazine |work=Astronomy.com |url=http://www.astronomy.com/en/sitecore/content/Home/News-Observing/News/2005/12/Uranus%20second%20ring-moon%20system.aspx |access-date=2014-11-22 |url-status=dead |archive-url=https://web.archive.org/web/20120331180954/http://www.astronomy.com/en/sitecore/content/Home/News-Observing/News/2005/12/Uranus%20second%20ring-moon%20system.aspx |archive-date=March 31, 2012 }}
</ref>
}}

== External links ==
* [http://hubblesite.org/newscenter/newsdesk/archive/releases/2003/29/ Hubble Uncovers Smallest Moons Yet Seen Around Uranus]&nbsp;– Hubble Space Telescope news release (25 September 2003)
* [http://hubblesite.org/newscenter/newsdesk/archive/releases/2005/33/ NASA's Hubble Discovers New Rings and Moons Around Uranus]&nbsp;– Hubble Space Telescope news release (22 December 2005)
* [https://web.archive.org/web/20081217064942/http://www.astronomy.com/asy/objects/images/layton_uranus2_700.jpg Hubble detects two large outer rings, two new moons orbiting Uranus] (Courtesy of Astronomy Magazine 2005)
* [http://www.dtm.ciw.edu/users/sheppard/satellites/urasatdata.html Uranus' Known Satellites] (by [[Biography:Scott S. Sheppard|Scott S. Sheppard]])

{{Uranus}}
{{Moons of Uranus}}
{{Solar System moons (compact)}}

{{DEFAULTSORT:Mab (Moon)}}
[[Category:Moons of Uranus]]

{{Sourceattribution|Mab (moon)}}