 During the transit, Mercury's tiny disk—jet black and perfectly round—will glide slowly across the face of the Sun. Only a speck of the Sun's surface is actually covered, so the Sun remains as dangerous as ever to look at. But with a proper filter and a little imagination, the Transit of Mercury can be a marvelous experience. There are many ways to safely observe the Sun, e.g., through eclipse glasses or by means of a pinhole projector. In this case, nothing beats a telescope equipped with a sun-safe H-alpha filter. H-alpha filters are narrowly tuned to the red glow of solar hydrogen. They reveal the Sun as a boiling inferno, cross-crossed by dark magnetic filaments and peppered with sunspots. What will it look like? A picture is worth a thousand words, | 
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