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[[File:Venusorbitsolarsystem.gif|thumb|Venus orbits the Sun at an average distance of about 108 million kilometres (about 0.7 [[Astronomical Unit|AU]]) and completes an orbit every 224.7 days. Venus is the second planet from the Sun and orbits the Sun approximately 1.6 times (yellow trail) in Earth's 365 days (blue trail)|alt=the orbits of Mercury, Venus, Earth and Mars are seen in motion from the top down against a spiderweb graph. Earth's orbit leaves a blue trail, while Venus's orbit leaves a yellow trail]]
Венера орбитира околу Сонцето на просечно растојание од околу {{convert|0.72|AU|e6km+e6mi|abbr=unit|lk=on}}, а завршува орбита на секои 224,7 дена. Иако сите [[planetary orbit|планетарни орбити]] се [[ellipse|елиптични]], орбитата на Венера е скоро [[circle|кружна]], со [[eccentricity (orbit)|ексцентричност]] помала од 0,01.<ref name="fact" /> Кога Венера лежи помеѓу Земјата и Сонцето во [[Conjunction (astronomy)#Superior and inferior|инфериорна врска]],таа има најблизок пристап до Земјата од која било планета на просечно растојание од 41 милион км (25 милиони ми).<ref name="fact" /> Планетата достигнува однос на секои 584 дена, просечно.<ref name="fact" /> Поради [[Milankovitch cycles#Orbital shape (eccentricity)|намалувањето на ексцентричноста на орбитата на Земјата]], минималните растојанија ќе станат поголеми во текот на следните десетици илјади години. Од 1 до 5383 година има 526 пристапи на помалку од 40 милиони километри; а потоа немало за околу 60,158 години.
Venus orbits the Sun at an average distance of about {{convert|0.72|AU|e6km+e6mi|abbr=unit|lk=on}}, and completes an orbit every 224.7 days. Although all [[planetary orbit]]s are [[ellipse|elliptical]], Venus's orbit is the closest to [[circle|circular]], with an [[eccentricity (orbit)|eccentricity]] of less than 0.01.<ref name="fact" /> When Venus lies between Earth and the Sun in [[Conjunction (astronomy)#Superior and inferior|inferior conjunction]], it makes the closest approach to Earth of any planet at an average distance of {{convert|41|e6km|e6mi|abbr=unit}}.<ref name="fact" /> The planet reaches inferior conjunction every 584 days, on average.<ref name="fact" /> Because of the [[Milankovitch cycles#Orbital shape (eccentricity)|decreasing eccentricity of Earth's orbit]], the minimum distances will become greater over tens of thousands of years. From the year 1 to 5383, there are 526 approaches less than 40 million km; then there are none for about 60,158 years.<ref>{{cite web |title=Venus Close Approaches to Earth as predicted by Solex 11 |url=http://home.surewest.net/kheider/astro/Solex-Venus.txt |archive-url=https://web.archive.org/web/20120809051650/http://home.surewest.net/kheider/astro/Solex-Venus.txt |archive-date=9 August 2012 |accessdate=19 March 2009}} Numbers generated by [https://web.archive.org/web/20150918233453/http://chemistry.unina.it/~alvitagl/solex/ Solex]</ref>
All the planets in the Solar System orbit the Sun in a [[anticlockwise]] direction as viewed from above Earth's north pole. Most planets also rotate on their axes in an anti-clockwise direction, but Venus rotates clockwise in [[Retrograde and prograde motion|retrograde rotation]] once every 243 Earth days—the slowest rotation of any planet. Because its rotation is so slow, Venus is very close to spherical.<ref name="Venus">{{cite web |title=Venus |url=http://www.britannica.com/EBchecked/topic/625665/Venus |work=Encyclopædia Britannica Online |last=Squyres |first=Steven W. |author-link=Steven W. Squyres |date=2016 |access-date=7 January 2016}}</ref> A Venusian [[sidereal day]] thus lasts longer than a Venusian year (243 versus 224.7 Earth days). Venus's equator rotates at {{convert|6.52|km/h|abbr=on}}, whereas Earth's rotates at {{convert|1669.8|km/h|abbr=on}}.<ref>{{cite book |chapterurl=https://books.google.com/books?id=PE99nOKjbXAC&lpg=PA50&pg=PA50 |chapter=Rotational velocity (equatorial) |title=The Cambridge Planetary Handbook |publisher=Cambridge University Press |last=Bakich |first=Michael E. |page=50 |date=2000 |isbn=978-0-521-63280-5}}</ref> Venus's rotation has slowed down in the 16 years between the ''Magellan'' spacecraft and ''Venus Express'' visits; each Venusian sidereal day has increased by 6.5 minutes in that time span.<ref name="slowing spin">{{cite web |url=http://www.esa.int/Our_Activities/Space_Science/Venus_Express/Could_Venus_be_shifting_gear |title=Could Venus Be Shifting Gear? |series=Venus Express |publisher=European Space Agency |date=10 February 2012 |access-date=7 January 2016}}</ref> Because of the retrograde rotation, the length of a [[solar day]] on Venus is significantly shorter than the sidereal day, at 116.75 Earth days (making the Venusian solar day shorter than [[Mercury (planet)|Mercury]]'s 176 Earth days).<ref name="planetary-facts">{{cite web |url=http://www.planetary.org/explore/space-topics/compare/planetary-facts.html |title=Planetary Facts |publisher=[[The Planetary Society]] |access-date=20 January 2016 |archive-url=https://web.archive.org/web/20120511011542/http://www.planetary.org/explore/space-topics/compare/planetary-facts.html |archive-date=11 May 2012 |deadurl=no}}</ref> One Venusian year is about 1.92 Venusian solar days.<ref name="compare">{{cite web |url=http://www.planetary.org/explore/topics/compare_the_planets/terrestrial.html |title=Space Topics: Compare the Planets |publisher=[[The Planetary Society]] |access-date=12 January 2016 |archive-url=https://web.archive.org/web/20060218084852/http://planetary.org/explore/topics/compare_the_planets/terrestrial.html |archive-date=18 February 2006}}</ref> To an observer on the surface of Venus, the Sun would rise in [[Poles of astronomical bodies|the west]] and set in the east,<ref name="compare" /> although Venus's opaque clouds prevent observing the Sun from the planet's surface.<ref>{{cite book |title=Solar System Voyage |author=Serge Brunier |authorlink=Serge Brunier |publisher=Cambridge University Press |year=2002 |page=40 |url=https://books.google.com/books?id=JkLxJOhEj-wC&pg=PA40 |isbn=978-0-521-80724-1 |translator-last=Dunlop |translator-first=Storm}}</ref>
Venus may have formed from the [[solar nebula]] with a different rotation period and obliquity, reaching its current state because of chaotic spin changes caused by planetary perturbations and [[tide|tidal]] effects on its dense atmosphere, a change that would have occurred over the course of billions of years. The rotation period of Venus may represent an equilibrium state between tidal locking to the Sun's gravitation, which tends to slow rotation, and an atmospheric tide created by solar heating of the thick Venusian atmosphere.<ref>{{cite journal |last1=Correia |first1=Alexandre C. M. |last2=Laskar |first2=Jacques |last3=De Surgy |first3=Olivier Néron |title=Long-Term Evolution of the Spin of Venus, Part I: Theory |journal=Icarus |volume=163 |issue=1 |pages=1–23 |date=May 2003 |url=http://www.imcce.fr/Equipes/ASD/preprints/prep.2002/venus1.2002.pdf |doi=10.1016/S0019-1035(03)00042-3 |bibcode=2003Icar..163....1C}}</ref><ref>{{cite journal |last1=Laskar |first1=Jacques |last2=De Surgy |first2=Olivier Néron |title=Long-Term Evolution of the Spin of Venus, Part II: Numerical Simulations |journal=Icarus |volume=163 |issue=1 |pages=24–45 |url=http://www.imcce.fr/Equipes/ASD/preprints/prep.2002/venus2.2002.pdf |doi=10.1016/S0019-1035(03)00043-5 |bibcode=2003Icar..163...24C|year=2003 }}</ref>
The 584-day average interval between successive close approaches to Earth is almost exactly equal to 5 Venusian solar days,<ref>{{cite journal |last1=Gold |first1=T. |last2=Soter |first2=S. |date=1969 |title=Atmospheric Tides and the Resonant Rotation of Venus |journal=Icarus |volume=11 |issue=3 |pages=356–66 |doi=10.1016/0019-1035(69)90068-2 |bibcode=1969Icar...11..356G}}</ref> but the hypothesis of a spin–orbit resonance with Earth has been discounted.<ref name=apj2_230_L123>{{Cite journal |last1=Shapiro |first1=I. I. |last2=Campbell |first2=D. B. |last3=De Campli |first3=W. M. |title=Nonresonance Rotation of Venus |journal=[[Astrophysical Journal]] |volume=230 |pages=L123–L126 |date=June 1979 |doi=10.1086/182975 |bibcode=1979ApJ...230L.123S}}</ref>
Venus has no natural satellites.<ref name="icarus202">{{cite journal |last1=Sheppard |first1=Scott S. |last2=Trujillo |first2=Chadwick A. |title=A Survey for Satellites of Venus |journal=Icarus |volume=202 |issue=1 |date=July 2009 |pages=12–16 |doi=10.1016/j.icarus.2009.02.008 |bibcode=2009Icar..202...12S |arxiv=0906.2781}}</ref> It has several [[trojan asteroid]]s: the [[quasi-satellite]] {{mpl|2002 VE|68}}<ref>{{cite journal |last1=Mikkola |first1=S. |last2=Brasser |first2=R. |last3=Wiegert |first3=P. |last4=Innanen |first4=K. |title=Asteroid 2002 VE68: A Quasi-Satellite of Venus |journal=[[Monthly Notices of the Royal Astronomical Society]] |volume=351 |issue=3 |page=L63 |date=July 2004 |doi=10.1111/j.1365-2966.2004.07994.x |bibcode=2004MNRAS.351L..63M}}</ref><ref>{{cite journal |first1=Carlos |last1=De la Fuente Marcos |last2=De la Fuente Marcos |first2=Raúl |title=On the Dynamical Evolution of 2002 VE68 |journal=[[Monthly Notices of the Royal Astronomical Society]] |volume=427 |issue=1 |pages=728–39 |date=November 2012 |doi=10.1111/j.1365-2966.2012.21936.x |bibcode=2012MNRAS.427..728D |arxiv=1208.4444}}</ref> and two other temporary trojans, {{mpl-|322756|2001 CK|32}} and {{mpl|2012 XE|133}}.<ref name=dynamics>{{Cite journal |title=Asteroid 2012 XE133: A Transient Companion to Venus |first1=Carlos |last1=De la Fuente Marcos |last2=De la Fuente Marcos |first2=Raúl |journal=Monthly Notices of the Royal Astronomical Society |volume=432 |issue=2 |pages=886–93 |doi=10.1093/mnras/stt454 |url=http://adsabs.harvard.edu/doi/10.1093/mnras/stt454 |arxiv=1303.3705 |bibcode=2013MNRAS.432..886D|date=June 2013}}</ref> In the 17th century, [[Giovanni Domenico Cassini|Giovanni Cassini]] reported a moon orbiting Venus, which was named [[Neith (hypothetical moon)|Neith]] and numerous sightings were reported over the following {{val|200|u=years}}, but most were determined to be stars in the vicinity. Alex Alemi's and [[David J. Stevenson|David Stevenson]]'s 2006 study of models of the early Solar System at the [[California Institute of Technology]] shows Venus likely had at least one moon created by a huge [[impact event]] billions of years ago.<ref>{{cite news |journal=[[Scientific American]] |date=10 October 2006 |title=Double Impact May Explain Why Venus Has No Moon |last=Musser |first=George |url=http://www.sciam.com/article.cfm?articleID=0008DCD1-0A66-152C-8A6683414B7F0000&ref=sciam |access-date=7 January 2016}}</ref> About 10 million years later, according to the study, another impact reversed the planet's spin direction and caused the Venusian moon gradually to [[Tidal deceleration|spiral inward]] until it collided with Venus.<ref>{{cite news |last=Tytell |first=David |journal=[[Sky & Telescope]] |date=10 October 2006 |title=Why Doesn't Venus Have a Moon? |url=http://www.skyandtelescope.com/astronomy-news/why-doesnt-venus-have-a-moon |access-date=7 January 2016}}</ref> If later impacts created moons, these were removed in the same way. An alternative explanation for the lack of satellites is the effect of strong solar tides, which can destabilize large satellites orbiting the inner terrestrial planets.<ref name="icarus202" />
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