Editing 1862 Apollo

{{Short description|Stony asteroid}}
{{Use dmy dates|date=October 2019}}
{{Infobox planet
 | minorplanet     = yes
 | name            = 1862 Apollo
 | symbol          = [[file:1862 Apollo symbol (bold).svg|24px]] (astrological)
 | background      = #FFC2E0
 | image           = 1862Apollo (Lightcurve Inversion).png
 | image_scale =
 | caption         = {{longitem|A three-dimensional model of 1862 Apollo based on its [[light-curve]]|style=padding:5px 0; line-height: 1.3em;}}
 | discovery_ref   = <ref name=jpldata />
 | discoverer      = [[K. Reinmuth]]
 | discovered      = 24 April 1932
 | discovery_site  = [[Landessternwarte Heidelberg-Königstuhl|Heidelberg Obs.]]
 | mpc_name        = (1862) Apollo
 | alt_names       = 1932 HA
 | pronounced      = {{IPAc-en|ə|ˈ|p|ɒ|l|oʊ}}<ref>{{Cite encyclopedia |url=http://www.lexico.com/definition/Apollo |archive-url=https://web.archive.org/web/20200321095651/https://www.lexico.com/definition/apollo |url-status=dead |archive-date=21 March 2020 |title=Apollo |dictionary=[[Lexico]] UK English Dictionary |publisher=[[Oxford University Press]]}}</ref>
 | named_after     = [[Apollo]]<br />{{small|(Greek mythology)}}
 | mp_category     = [[Near-Earth object|NEO]]{{·}}[[Potentially hazardous asteroid|PHA]]<br />[[Venus-crosser]]<br />[[Mars-crosser]]<br />[[Apollo asteroids]]
 | orbit_ref       = <ref name="jpldata" />
 | epoch           = 29 December 2009 ([[Julian day|JD]] 2455194.5)
 | uncertainty     = 0
 | observation_arc = 85.32 yr (31162 days)
 | earliest_precovery_date = 13 December 1930
 | aphelion        = {{Convert|2.2935|AU|Gm|abbr=on|lk=on}}
 | perihelion      = {{Convert|0.64699|AU|Gm|abbr=on}}
 | semimajor       = {{Convert|1.4702|AU|Gm|abbr=on}}
 | eccentricity    = 0.55994
 | period          = 1.78 [[Julian year (astronomy)|yr]] (651.15 [[Julian year (astronomy)|d]])
 | mean_anomaly    = 144.22[[Degree (angle)|°]]
 | inclination     = 6.3530°
 | asc_node        = 35.739°
 | arg_peri        = 285.85°
 | moid            = {{Convert|0.0257026|AU|Gm|abbr=on}}
 | dimensions      = {{convert|1.5|km|mi|abbr=on}}<ref name="Gehrels" />
 | mass            =
 | density         =
 | rotation        = {{Convert|3.065|h|d|abbr=on|lk=on}}
 | spectral_type   = [[Q-type asteroid|Q]] {{small|([[Tholen classification|Tholen]], [[SMASS classification|SMASS]])}}<br />[[Asteroid color indices|B–V]] = 0.819<br />[[Asteroid color indices|U–B]] = 0.481
 | abs_magnitude   = 16.25<ref name="jpldata" />
 | albedo          = 0.25<ref name=jpldata/><ref name="Gehrels" />
 | temp_name1      = Kelvin<ref name="PHL">{{cite web | url=http://phl.upr.edu/projects/habitable-exoplanets-catalog/calculators | title=Planetary Habitability Calculators | publisher=University of Puerto Rico at Arecibo | work=Planetary Habitability Laboratory | accessdate=7 December 2015 | archive-date=11 May 2019 | archive-url=https://web.archive.org/web/20190511110804/http://phl.upr.edu/projects/habitable-exoplanets-catalog/calculators | url-status=dead }}</ref>
 | min_temp_1      = 171 K
 | mean_temp_1     = 214 K
 | max_temp_1      = 322 K
 | temp_name2      = Celsius
 | min_temp_2      = -102°C
 | mean_temp_2     = -59°C
 | max_temp_2      = 49°C
 | temp_name3      = Fahrenheit
 | min_temp_3      = -151.6°F
 | mean_temp_3     = -74.2°F
 | max_temp_3      = 120.2°F
 | mean_motion     = {{Deg2DMS|0.55287|sup=ms}} / day
 | mean_radius     = 0.75 [[Kilometre|km]]
 | jupiter_moid    = {{Convert|3.06837|AU|Gm|abbr=on}}
 | tisserand       = 4.415
}}

'''1862 Apollo''' {{IPAc-en|ə|ˈ|p|ɒ|l|oʊ}} is a stony [[asteroid]], approximately 1.5 kilometers in diameter, classified as a [[near-Earth object]] (NEO). It was discovered by German astronomer [[Karl Reinmuth]] at [[Landessternwarte Heidelberg-Königstuhl|Heidelberg Observatory]] on 24 April 1932, but lost and not recovered until 1973.

It is the namesake and the first recognized member of the [[Apollo asteroid]]s, a subgroup of NEOs which are [[Earth-crosser asteroid|Earth-crossers]], that is, they cross the orbit of the Earth when viewed perpendicularly to the ecliptic plane (crossing an orbit is a more general term than actually intersecting it). In addition, since Apollo's orbit is highly [[orbital eccentricity|eccentric]], it crosses the orbits of Venus and Mars and is therefore called a [[Venus-crosser]] and [[Mars-crosser]] as well.

Although Apollo was the first Apollo asteroid to be discovered, its official IAU-number (1862) is higher than that of some other Apollo asteroids such as [[1566 Icarus]], because it was a [[Lost minor planet|lost asteroid]] for more than 40 years and other bodies were numbered in the meantime. The analysis of its rotation provided observational evidence of the [[YORP effect]].<ref name="yorp"/>

It is named after the Greek god [[Apollo]]. He is the god of the Sun, child of Zeus and Leto, after which the minor planets [[5731 Zeus]] and [[68 Leto]] are named.<ref name="springer" />

== Satellite ==
On November 4, 2005, it was announced that an [[asteroid moon]], or satellite of Apollo, had been detected by radar observations from [[Arecibo Observatory]], [[Puerto Rico]], October 29 &ndash; November 2, 2005. The announcement is contained in the [[International Astronomical Union]] Circular (IAUC) 8627.<ref>{{cite web | url=http://www.cbat.eps.harvard.edu/iauc/08600/08627.html | title=IAU Circular No. 8627 | publisher=Central Bureau for Astronomical Telegrams | work=International Astronomical Union | accessdate=8 December 2015}}</ref> The satellite is only {{convert|80|m|ft|abbr=on}} across and orbits Apollo just {{convert|3|km|mi|abbr=on}} away from the asteroid itself.<ref name="archive">{{cite web | url=http://www.johnstonsarchive.net/astro/astmoons/am-01862.html | title=(1862) Apollo | work=Johnston's Archive | date=November 16, 2014 | accessdate=8 December 2015 | author=Johnston, Wm. Robert}}</ref> From the surface of Apollo, S/2005 (1862) 1 would have an angular diameter of about 2.0835 degrees.<ref group="lower-alpha">Calculated from the formula <math>\delta</math> = (206265) ''d'' / ''D'' arcseconds. (see [[Angular diameter]])</ref>

== Potentially hazardous object ==
1862 Apollo is a [[potentially hazardous asteroid]] (PHA) because its [[minimum orbit intersection distance]] (MOID) is less than 0.05 AU and its diameter is greater than 150 meters. Apollo's Earth MOID is {{convert|0.0257|AU|km mi|abbr=on|lk=on}}.<ref name=jpldata /> Its orbit is well-determined for the next several hundred years. On 17 May 2075 it will pass {{convert|0.0083|AU|km mi|abbr=on|lk=off}} from [[Venus]].<ref name=jpldata />

== See also ==
* [[Lost asteroid]]

== Notes ==
{{notelist}}

== References ==
{{reflist
| refs =

<ref name=jpldata>{{cite web
  |type=2015-03-16 last obs.
  |title=JPL Small-Body Database Browser: 1862 Apollo (1932 HA)
  |url=https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=2001862
  |publisher=[[Jet Propulsion Laboratory]]
  |accessdate=20 April 2016}}</ref>

<ref name="Gehrels">{{cite book
  |last=Gehrels
  |first=Tom
  |title=Hazards Due to Comets and Asteroids
  |date=1994
  |publisher=[[University of Arizona Press]]
  |location=Tucson
  |isbn=978-0816515059
  |pages=540–543}}</ref>

<ref name="springer">{{cite book
  |title=Dictionary of Minor Planet Names – (1862) Apollo
  |last=Schmadel |first=Lutz D.
  |publisher=[[Springer Berlin Heidelberg]]
  |page=149
  |date=2003
  |isbn=978-3-540-29925-7
  |doi=10.1007/978-3-540-29925-7_1863
  |chapter = (1862) Apollo}}</ref>

<ref name="yorp">{{Cite journal
 |title = New photometric observations of asteroids (1862) Apollo and (25143) Itokawa – an analysis of YORP effect
 |last = Durech
 |first = J.
 |date = September 2008
 |journal = [[Astronomy and Astrophysics]]
 |volume = 488
 |issue = 1
 |pages = 345–350
 |doi = 10.1051/0004-6361:200809663
 |url = http://www.rni.helsinki.fi/~mjk/YorpApoIto.pdf
 |last2 = Vokrouhlický
 |first2 = D.
 |last3 = Kaasalainen
 |first3 = M.
 |last4 = Weissman
 |first4 = P.
 |last5 = Lowry
 |first5 = S. C.
 |last6 = Beshore
 |first6 = E.
 |last7 = Higgins
 |first7 = D.
 |last8 = Krugly
 |first8 = Y. N.
 |last9 = Shevchenko
 |first9 = V. G.
 |display-authors=8
 |bibcode=2008A&A...488..345D|doi-access = free
 }}</ref>
}} <!-- end of reflist -->

== External links ==
* [http://www.minorplanetobserver.com/pdolc/A1862_2005.HTM Lightcurve plot of 1862 Apollo], Palmer Divide Observatory, ''[[Brian D. Warner|B. D. Warner]]'' (2005)
* [http://www.johnstonsarchive.net/astro/asteroidmoons.html Asteroids with Satellites], Robert Johnston, johnstonsarchive.net
* [http://www.minorplanet.info/PHP/lcdbsummaryquery.php Asteroid Lightcurve Database (LCDB)], query form ([http://www.minorplanet.info/lightcurvedatabase.html info] {{Webarchive|url=https://web.archive.org/web/20171216050541/http://www.minorplanet.info/lightcurvedatabase.html |date=16 December 2017 }})
* [https://books.google.com/books?id=aeAg1X7afOoC&pg Dictionary of Minor Planet Names], Google books
* [http://obswww.unige.ch/~behrend/page_cou.html Asteroids and comets rotation curves, CdR] – Observatoire de Genève, Raoul Behrend
* {{NeoDys|1862}}
* {{ESA-SSA|1862|Apollo}}
* {{JPL small body}}

{{Minor planets navigator |1861 Komenský |number=1862 |1863 Antinous}}
{{Small Solar System bodies}}
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{{DEFAULTSORT:Apollo}}
[[Category:Apollo asteroids|001862]]
[[Category:Discoveries by Karl Wilhelm Reinmuth]]
[[Category:Named minor planets]]
[[Category:Binary asteroids|001862]]
[[Category:Potentially hazardous asteroids|001862]]
[[Category:Earth-crossing asteroids]]
[[Category:Venus-crossing asteroids]]
[[Category:Q-type asteroids (Tholen)|001862]]
[[Category:Q-type asteroids (SMASS)|001862]]
[[Category:Astronomical objects discovered in 1932|19320424]]
[[Category:Recovered astronomical objects|01862]]