View source for 354 Eleonora

{{Short description|Main-belt asteroid}}
{{Use dmy dates|date=July 2018}}
{{Infobox planet
| minorplanet = yes
| background = #D6D6D6
| name = 354 Eleonora
| image = 354 Eleonora VLT (2021), deconvolved.pdf
| image_size = 
| caption = 
| discoverer = [[Auguste Charlois]]
| discovered = 17 January 1893
| mpc_name = (354) Eleonora
| pronounced = {{IPAc-en|ɛ|l|i|ə|ˈ|n|ɔːr|ə}}<ref>{{OED|Eleonora}}</ref>
| adjective = Eleonorian
| alt_names = 1893 A
| mp_category = [[Asteroid belt|Main belt]]
| orbit_ref = <ref name="JPL"/>
| epoch = 31 July 2016 ([[Julian day|JD]] 2457600.5)
| semimajor = {{Convert|2.79777|AU|Gm|abbr=on}}
| perihelion = {{Convert|2.47676|AU|Gm|abbr=on}}
| aphelion = {{Convert|3.1188|AU|Gm|abbr=on|lk=on}}
| eccentricity = 0.11474
| period = 4.68 [[Julian year (astronomy)|yr]] (1709.3 [[Julian year (astronomy)|d]])
| inclination = 18.403°
| asc_node = 140.37°
| arg_peri = 5.5215°
| mean_anomaly = 123.762[[Degree (angle)|°]]
| dimensions = 0.25{{efn|1=Flattening derived from the maximum aspect ratio (c/a): <math>f=1-\frac{c}{a}</math>, where (c/a) = {{val|0.75|0.08}}.<ref name=VLT/>}}
| mean_diameter = {{val|165|3|u=km}}<ref name=VLT>P. Vernazza et al. (2021) VLT/SPHERE imaging survey of the largest main-belt asteroids: Final results and synthesis. ''Astronomy & Astrophysics'' 54, A56</ref><br />{{val|154.3|5.6|u=km}}<ref name="Carry2012"/><br />{{val|148.970|0.425|ul=km}}<ref name="FiengaEtAl2020"/><ref name="JPL"/>
| mass = {{val|7.5|2.7|e=18|u=kg}}<ref name=VLT/><br />{{val|7.18|2.57|e=18|u=kg}}<ref name="Carry2012"/><br>{{nwr|(6.236 ± 1.305/1.214){{e|18}} kg<ref name="FiengaEtAl2020"/>}}
| density = {{val|3.18|1.14|u=g/cm3}}<ref name=VLT/><br />{{val|3.73|1.39|u=g/cm3}}<ref name="Carry2012"/><br>3.602 ± 0.754/0.701 g/cm{{sup|3}}<ref name="FiengaEtAl2020"/>
| rotation = {{Convert|4.277|h|d|abbr=on|lk=on}}<ref name="JPL"/>
| spectral_type = [[S-type asteroid|S]]
| abs_magnitude = 6.15<ref name="JPL"/>
| albedo = 0.172<ref name=VLT/><br />{{val|0.201|0.052}}<ref name="JPL"/>
| mean_motion = {{Deg2DMS|0.21061|sup=ms}} / day
| observation_arc = 123.16 yr (44983 d)
| uncertainty = 0
}}

'''354 Eleonora''' is a large, stony [[Asteroid belt|main-belt]] [[asteroid]] that was discovered by the French astronomer [[Auguste Charlois]] on January 17, 1893, in [[Nice]].<ref name="IAU_MPC"/>

[[Photometry (astronomy)|Photometric]] observations of this asteroid gave a [[light curve]] with a period of 13.623 hours. The data was used to construct a model for the asteroid, revealing it to be a regular-shaped object, spinning about a pole with ecliptic coordinates (β, λ) = (+20°, 356°), although this is with an accuracy of only ±10°. The ratio of the major to minor axes lengths is roughly equal to 1.2.<ref name="Kaasalainen2002"/> It is classified as an [[S-type asteroid]] and has an estimated size of 154.34&nbsp;km.<ref name="Carry2012"/> The spectrum of 354 Eleonora reveals the strong presence of the mineral [[olivine]], a relative rarity in the asteroid belt.<ref name="Burbine2000"/>

During favorable [[Opposition (astronomy)|opposition]]s, such as in 1968 and 2010, Eleonora can reach an [[apparent magnitude]] of +9.31.

==Notes==
{{notelist}}

==References==
{{Reflist|refs=
<ref name="IAU_MPC">{{Citation
 | title     = Numbered Minor Planets 1–5000
 | work      = Discovery Circumstances
 | publisher = IAU Minor Planet center
 | url       = https://www.minorplanetcenter.net/iau/lists/NumberedMPs000001.html
 | access-date= 2013-04-07
 | postscript= .
}}</ref>

<ref name="JPL">{{Citation
 | first1    = Donald K.
 | last1     = Yeomans
 | title     = 354 Eleonora
 | work      = JPL Small-Body Database Browser
 | publisher = [[NASA Jet Propulsion Laboratory]]
 | url       = https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=354
 | access-date= 11 May 2016
 | postscript= .
}}</ref>

<ref name="Carry2012">{{Citation
 | first1    = B.
 | last1     = Carry
 | title     = Density of asteroids
 | journal      = Planetary and Space Science
 | volume    = 73
 | pages      = 98–118
 |date=December 2012
 | issue = 1
 | doi       = 10.1016/j.pss.2012.03.009
 | bibcode   = 2012P&SS...73...98C
 | postscript= .
|arxiv = 1203.4336 | s2cid = 119226456
 }} See Table 1.</ref>

<ref name="Burbine2000">{{Citation
 | first1    = T. H.
 | last1     = Burbine
 | first2    = E.
 | last2     = Bowden
 | first3    = T.
 | last3     = Ogura
 | first4    = R. P.
 | last4     = Binzel
 | first5    = S. J.
 | last5     = Bus
 | first6    = T. J.
 | last6     = McCoy
 | first7    = K.
 | last7     = Kondo
 | display-authors = 1
 | title     = The Nature of Olivine Asteroids
 | work      = Meteoritics & Planetary Science
 | volume    = 35
 | pages     = A35
 |date=July 2000
 | bibcode   = 2000M&PSA..35R..35B
 | postscript= .
 | doi=10.1111/j.1945-5100.2000.tb01796.x
| doi-access= free
 }}</ref>

<ref name="Kaasalainen2002">{{Citation
 | last1     = Kaasalainen
 | first1    = M.
 | last2     = Torppa
 | first2    = J.
 | last3     = Piironen
 | first3    = J.
 | display-authors = 1
 | title     = Models of Twenty Asteroids from Photometric Data
 | journal      = Icarus
 | volume    = 159
 | issue     = 2
 | pages     = 369–395
 |date=October 2002
 | doi       = 10.1006/icar.2002.6907
 | bibcode   = 2002Icar..159..369K
 | postscript= .
}}</ref>

<ref name="FiengaEtAl2020">{{Cite journal 
  |last=Fienga |first=A.
  |last2=Avdellidou |first2=C.
  |last3=Hanuš |first3=J.
  |date=February 2020
  |title=Asteroid masses obtained with INPOP planetary ephemerides
  |url=https://academic.oup.com/mnras/article/492/1/589/5658701
  |journal=Monthly Notices of the Royal Astronomical Society
  |volume=492
  |issue=1
  |doi=10.1093/mnras/stz3407
  |doi-access=free
}}</ref>

}}

== External links ==
* {{AstDys|354}}
* {{JPL small body}}

{{Minor planets navigator |353 Ruperto-Carola |number=354 |355 Gabriella}}
{{Small Solar System bodies}}
{{Authority control}}

{{DEFAULTSORT:Eleonora}}
[[Category:Background asteroids|000354]]
[[Category:Discoveries by Auguste Charlois]]
[[Category:Named minor planets]]
[[Category:S-type asteroids (Tholen)|000354]]
[[Category:Sl-type asteroids (SMASS)|000354]]
[[Category:Astronomical objects discovered in 1893|18930117]]


{{S-beltasteroid-stub}}