The transit of Venus!
Source - NASA
That black dot is Venus, passing in front of the sun as viewed from Earth in June 2004. On Wednesday in Asia, we will see Venus transit again. The next time after that will be in December 2117. These transits come in an odd pattern, occuring in pairs separated by eight years, but successive pairs have a gap of over a century in between. The reason for this is the angle between the orbits of Earth and Venus.
In North America, the transit takes place on Tuesday, June 5. Penn State's astronomy department offers free eclipse glasses and some links for Venus transit events held in Pennsylvania. Discovery Magazine's blog, Bad Astronomy, has a great post on background information (what we can learn from the transits), safety tips, and resources for watching the transit online. NASA, for instance, will provide live streaming of this rare celestial event.
I must admit I haven't been someone that's kept up with things such as solar or lunar eclipses. Apparently my dad had seen the transit in 2004, way before I found my interest for astronomy. Considering the significance of planets and their transits in the field of exoplanets, I have to say this is a must-see for me. I've wanted to witness this ever since I heard about it in class. One particular story, also recounted in Parallax, from that lecture has stuck with me.
To catch the transit of 1761, French astronomer Guillaume Le Gentil was sent to a French colony in India. With delays and setbacks due to the Seven Years' War, a consequence of which was the capture of that colony by the British, Le Gentil was at sea during the transit. There were clear skies that day, but a rocking ship is not the ideal platform for proper observation.
Travels of such distances were by no means fast back then. However, even if you had come so far, through obstacles and bad luck, would you have done what Le Gentil did next? He chose to stay in that region and wait for the next transit, due to arrive in eight years.
For the transit of 1769, he had originally planned to observe from the Philippines. Once again, territorial issues arose. The Spanish occupiers of Manila did not welcome him warmly, causing Le Gentil to return to that colony in India, which had been restored to France after the war.
Finally, the day of the transit came - and that's when the clouds rolled in, obscuring any chance of observation.
Following the second unsuccessful attempt at observing the transit, Le Gentil headed home. Perhaps the worst part of the story comes next: since his departure, he discovered, he had been declared legally dead, his wife had remarried, and his possessions had been pludered.
Above his ability to survive through all that misfortune, I have to admire his dedication. We are lucky to live in a time where events like the transit can be streamed over the internet. But even with such resources, here's to hoping the skies will be clear during the last Venus transit of our lives!