Transit of Venus

A transit of Venus takes place when <a href="/facts/Venus/pADnueP6">Venus</a> passes directly between the <a href="/facts/Sun/CadPCVHh">Sun</a> and the Earth (or any other <a href="/facts/Inferior_and_superior_planets/DeyDm82H">superior planet</a>), becoming visible against (and hence obscuring a small portion of) the <a href="/facts/Solar_disk/ufytegG3">solar disk</a>. During a <a href="/facts/Astronomical_transit/4s6Mll1a">transit</a>, Venus is visible as a small black circle moving across the face of the Sun.
Transits of Venus reoccur periodically. A pair of transits takes place eight years apart in December (<a href="/facts/Gregorian_calendar/axJfTXV1">Gregorian calendar</a>) followed by a gap of 121.5 years, before another pair occurs eight years apart in June, followed by another gap, of 105.5 years. The dates advance by about two days per 243-year cycle. The periodicity is a reflection of the fact that the <a href="/facts/Orbital_period/94f56uh2">orbital periods</a> of Earth and Venus <a href="/facts/Orbital_resonance/eQLMfBWu">are close</a> to 8:13 and 243:395 <a href="/facts/Commensurability_(astronomy)/rhchMwV2">commensurabilities</a>. The last pairs of transits occurred on <a href="/facts/Transit_of_Venus,_2004/wEL6lAWS">8 June 2004</a> and <a href="/facts/2012_transit_of_Venus/BajVV6pe">5–6 June 2012</a>. The next pair of transits will occur on 10–11 December 2117 and 8 December 2125.
Transits of Venus were in the past used to determine the size of the <a href="/facts/Solar_System/QIcLSazQ">Solar System</a>. The 2012 transit has provided research opportunities, particularly in the refinement of techniques to be used in the search for <a href="/facts/Exoplanet/zjfmqfUf">exoplanets</a>.

Transit of Venus open-in-new

Transit of Venus