Scope Diagram Astrocamera.Net - Astrophotography by Dave Kodama

Transits



Transits of the inner planets across the face of the sun are relatively rare compared to solar or lunar eclipses. If the orbits of Mercury, Venus, and Earth were in the same plane, each time the inner planets passed us, we would see a transit of the planet across the sun, with Mercury transits seen more often than Venus transits because it orbits the sun faster.
 
However, because the orbits of the inner planets are tilted relative to ours, we see a transit only when the inner planets are crossing our orbital plane. Transits of Venus are especially rare, with pairs of them happening more than a century apart, so they are worth making a special effort to see.
 

Transits of Mercury

1999 Transit of Mercury 2006 Transit of Mercury
15 November 1999 8 November 2006

 

Transits of Venus

Venus Transit 2012 Transit of Venus
8 June 2004 5 June 2012

 

Recent and Upcoming Transits

Mercury
15 Nov. 1999
07 May 2003
08 Nov. 2006
09 May 2016
11 Nov. 2019
13 Nov. 2032
Venus
08 June 2004
06 June 2012
 
11 Dec. 2117
08 Dec. 2125