WARNING: IT IS EXTREMELY DANGEROUS TO LOOK AT THE SUN. SERIOUS EYE DAMAGE MAY RESULT.
A transit will not always occur when Mercury or Venus passes between the Earth and the Sun, as they will usually they pass either above or below the Sun, as viewed from Earth. Transits of Mercury are quite rare, occuring only 13 times per century, in either May or November. Don’t worry too much if you missed this transit as there will be another one visible on 9 May 2016, 11 November 2019, or for Australian observers, in the afternoon of 13th November 2032.
The table below provides times of the transit for the capital cities in Australia: (All times are local time, including Daylight Savings Time where applicable)
|Location||Sunrise||Contact I||Contact II||Contact III||Contact IV|
There are many explanations for the black drop effect. In previous years, it was believed by some that this effect was due to the atmosphere of Venus or Mercury (thus an illusion), however, as Venus' atmosphere is too thin to be responsible, and Mercury's atmosphere virtually non-existent, we now know that it is not an illusion. The “black drop effect” has recently been photographed by the TRACE spacecraft during previous transits of Mercury. Recent explanations suggest the black drop effect may be a combination of blurring caused by the Earth’s atmosphere, with the dimming of the Sun’s disc close to its edge.
The best way to observe the transit safely is to visit your local amateur astronomical society, observatory or planetarium. These groups are likely to be running public viewing sessions for the transit.
With Mercury being such a small planet, a powerful telescope will be needed if you want to observe the transit safely yourself, using the telescope to project an image of the sun onto a large flat surface. NOTE: DO NOT LOOK THROUGH THE TELESCOPE OR THE FINDERSCOPE, but instead use the shadow of the telescope to aim it directly at the sun, and you should see the Sun’s bright disc projected onto the flat surface.
You may need to adjust the focus of the projected image, until the tiny black spot of Mercury can be seen clearly and sharply. The spot will only be about 1/194th of the Sun’s diameter, however should still be seen. Viewing the projected image using this method is quite safe, however looking through the telescope will cause instant blindness. DO NOT LEAVE THE TELESCOPE UNATTENDED ESPECIALLY WHEN CHILDREN ARE PRESENT.
During the 2006 transit (for Eastern Australian observers) there will be four moments when the disc of Mercury comes into contact with the Sun at a single point. First contact will occur just as Mercury initially touches the solar disc. Second contact is at the exact second when Mercury has fully “entered” the Sun’s disc. Third Contact is at the exact second when Mercury touches the edge of the Sun's disc on its way out, and Fourth Contact is the exact second when Mercury leaves the edge of the Sun's disc.