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.
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