About this Image
On June 5-6 2012, SDO is collecting images of one of the rarest predictable solar events: the transit of Venus across the face of the sun. This event happens in pairs eight years apart that are separated from each other by 105 or 121 years. The last transit was in 2004 and the next will not happen until 2117. This image was captured on June 5, 2012.   — Credit: NASA/SDO/AIA

The 2012 Venus Transit – a celestial event that won’t be seen again for more than a century.

Transits happen when a planet crosses between Earth and the sun. Only Mercury and Venus, which are closer to the sun than our planet, can undergo this unusual alignment.
With its relatively tight orbit, Mercury circles the sun fast enough that we see the innermost planet transit every 13 to 14 years. But transits of Venus are exceedingly rare, due to that world’s tilted orbit: After the 2012 Venus transit, we won’t see another until 2117.

About this Image
On June 5, 2012, Hinode captured this stunning view of the transit of Venus — the last instance of this rare phenomenon until 2117. Hinode is a joint JAXA/NASA mission to study the connections of the sun’s surface magnetism, primarily in and around sunspots. NASA’s Marshall Space Flight Center in Huntsville, Ala., manages Hinode science operations and oversaw development of the scientific instrumentation provided for the mission by NASA, and industry. The Smithsonian Astrophysical Observatory in Cambridge, Mass., is the lead U.S. investigator for the X-ray Telescope.   –Credit: JAXA/NASA
 

During the June 5-6, 2012 transit, Venus looked like a black dot gliding across the face of the sun over the course of about six hours.

Venus’s diameter appeared to be only about a 30th the diameter of the sun, so it looked … like a pea in front of a watermelon.

Here we present video of the Venus transit as seen in the 171 wavelength. This channel is especially good at showing coronal loops – the arcs extending off of the Sun where plasma moves along magnetic field lines. The brightest spots seen here are locations where the magnetic field near the surface is exceptionally strong.

Credit: NASA SDO

Worth a look: