View source for 280 Philia

{{Short description|Main-belt asteroid}}
{{Use dmy dates|date=October 2019}}
{{Infobox planet
| minorplanet     = yes
| background      = #D6D6D6
| name            = 280 Philia
| discoverer      = [[Johann Palisa]]
| discovered      = 29 October 1888
|image= Орбита астероида 280.png
|caption=Orbital diagram
| mpc_name        = (280) Philia
| pronounced      = {{IPAc-en|'|f|ɪ|l|i|ə}}
| alt_names       = A888 UB
| named_after     = [[Philia (nymph)]]
| mp_category     = [[Asteroid belt|Main belt]]
| epoch           = 31 July 2016 ([[Julian day|JD]] 2457600.5)
| semimajor       = {{Convert|2.94460|AU|Gm|abbr=on}}
| perihelion      = {{Convert|2.62787|AU|Gm|abbr=on}}
| aphelion        = {{Convert|3.26133|AU|Gm|abbr=on|lk=on}}
| eccentricity    = 0.10756
| period          = {{convert|1845.6|days|years|2|order=flip|abbr=on}}
| inclination     = 7.44582°
| asc_node        = 9.91179°
| arg_peri        = 90.0510°
| mean_anomaly    = 52.7987[[Degree (angle)|°]]
| dimensions      = {{val|45.69|2.0|ul=km}}
| mass            =
| density         =
| rotation        = {{Convert|70.26|h|d|abbr=on|lk=on}}
| spectral_type   =
| abs_magnitude   = 10.9
| albedo          = {{val|0.0444|0.004}}
| mean_motion     = {{Deg2DMS|0.195059|sup=ms}} / day
| orbit_ref       = <ref name="jpldata"/>
| observation_arc = {{convert|46083|days|years|2|order=flip|abbr=on}}
| uncertainty     = 0
}}
'''280 Philia''' is a fairly large [[Asteroid belt|Main belt]] [[asteroid]].<ref name=Lewis2003/> It was discovered by [[Johann Palisa]] on 29 October 1888 at the [[Vienna Observatory]].
Sparse data collected during a 1987 study indicated this asteroid has a [[rotation period]] of approximately 64 hours, which is much longer than can be continually observed from one site. During 2010−2011, an international collaboration to study the asteroid collected 9,037 [[photometry (astronomy)|photometric]] data points over 38 sessions. The resulting [[light curve]] analysis displays a [[rotation period]] of {{val|70.26|0.03|u=hours}} with a brightness variation of {{val|0.15|0.02}} in [[apparent magnitude|magnitude]].<ref name=Pilcher_et_al_2011/>
==References==
{{reflist|refs=
<ref name="jpldata">{{Cite web
| url=https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=280
| title=280 Philia | work=[[JPL Small-Body Database]]
| publisher=[[NASA]]/[[Jet Propulsion Laboratory]]
| access-date=11 May 2016}}</ref>
<ref name=Lewis2003>{{cite book
| url=https://books.google.com/books?id=lmv4930JbY0C&q=280+Philia+asteroid&pg=PA521
| title=The Encyclopedia of Heavenly Influences
| first=James R. | last=Lewis
| year=2003|page=521|isbn=9781578591442
| access-date=6 April 2015 }}</ref>
<ref name=Pilcher_et_al_2011>{{citation
| title=Rotation Period Determination for 280 Philia - A Triumph of Global Collaboration
| last1=Pilcher | first1=Frederick | last2=Benishek | first2=Vladimir
| last3=Ferrero | first3=Andrea | last4=Hamanowa | first4=Hiromi
| last5=Mananowa | first5=Hiroko | last6=Stephens | first6=Robert D.
| work=Bulletin of the Minor Planets Section of the Association of Lunar and Planetary Observers
| volume=38 | issue=3 | pages=127–128 | date=July 2011
| display-authors=1 | bibcode=2011MPBu...38..127P | postscript=. }}</ref>
}}
==External links==
* {{AstDys|280}}
* {{JPL small body}}
{{Minor planets navigator |279 Thule |number=280 |281 Lucretia}}
{{Small Solar System bodies}}
{{Authority control}}
{{DEFAULTSORT:000280}}
[[Category:Background asteroids]]
[[Category:Discoveries by Johann Palisa|Philia]]
[[Category:Named minor planets|Philia]]
[[Category:Astronomical objects discovered in 1888|18881029]]
{{Beltasteroid-stub}}