For everyone "it is absolutely worth seeing it live", noted Giuseppe Cutispoto, of the National Institute of Astrophysics (Inaf) of Catania. Since Mercury is closer to the Sun than the Earth is, it passes constantly between our planet and the Sun, but its orbit is inclined with respect to the Earth's; it is possible to observe the transit on the solar disk only when the two orbits intersect.
On 11 November "Mercury will be perfectly aligned between the Earth and the Sun", said astrophysicist Gianluca Masi, head of the Virtual Telescope. At the moment of transit, the smallest planet in the Solar System will be 101 million kilometers away. "From the Earth – added Masi – the planet will be seen, over the course of a few hours, as a small black disk that runs on the background of the great disk of the Sun".
Observing the transit until the end will be possible only from Central and South America; in Italy it will be observable starting from 13:35 on Monday 11 November until 18:04, then again for a while after sunset; the climax will be at 3.20pm. If the clouds should ruin the show, don't worry: you can watch the transit online thanks to live streaming organized by the National Telescope Galileo and the Virtual Telescope.