In case you missed it Tuesday, the 2012 transit of Venus across the sun was one of the very rare astronomical events we “regular folk” can watch and appreciate with little scientific instrumentation. Like eclipses, transits are one of the few “sciency things” that garner public attention and appreciation any more. Tuesday’s transit, lasting about 6 hours, was the last time Earthlings will get to see our “sister planet” until December 2117. Fortunately, our technology has improved a little bit since the last pair of transits, and we have been afforded multiple opportunities to watch the actual event. I was watching the live webcast from the NOAA Mauna Loa Observatory in Hawaii.
Events like this always strike me with a real sense of scale and I am imbued with renewed reverence for the Universe itself and for modern science’s efforts to understand it. Venus is nearly the same size as our own planet, yet it looks so small against the burning disc of the sun. There are sunspots that look like tiny flecks on Sol’s surface which are, in reality, large enough to swallow our world whole. Even solar prominences–massive plumes of plasma arcing across the solar surface–that could swallow Jupiter (a planet with a diameter 11 times that of our Earth’s) with little effort.
I think the Warners said it best when they stated that it’s “a great big Universe, and we’re not.”
NASA’s Goddard Space Flight Center released a stunning time-lapse video of the transit that’s available on YouTube and free download from their website. The footage was shot from the Solar Dynamics Observatory and shows the transit in various wavelengths with varying levels of detail. From Goddard Multimedia:
The videos and images displayed here are constructed from several wavelengths of extreme ultraviolet light and a portion of the visible spectrum. The red colored sun is the 304 angstrom ultraviolet, the golden colored sun is 171 angstrom, the magenta sun is 1700 angstrom, and the orange sun is filtered visible light. 304 and 171 show the atmosphere of the sun, which does not appear in the visible part of the spectrum.