Mercury orbits the sun every 88 days, “so you’d think it (a transit) wouldn’t be incredibly rare”, said Thomas Willmitch, ISU Planetarium director. That is, except for 13 to 14 times per century, when the orbits are aligned such that Mercury passes directly in front of the Sun in what astronomers call a transit.
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For those who want to watch the event take place, it’s advised that you find a safe way to use a telescope or binoculars, because staring directly into the sun can be detrimental to your health.
For the rest of us, the transit will begin at 7:16 a.m. ET and be visible for seven hours, so for people in the West, it will already be in progress when the sun rises. It is mandatory that these are outfitted with a solar filter, else you risk damaging your eyes.
The last transit of Mercury. “When Mercury is in front of the sun, we can study the exosphere close to the planet”, NASA scientist Rosemary Killen said in a release from the Jet Propulsion Laboratory. Due to the extremely tiny size, in order to observe the transit with adequate precautions, it is necessary to either use a telescope or a binocular filled with solar filters.
The first planet in our solar system can be seen making a transit across the face of the sun by people around the world.
Mercury is so small it won’t be visible without magnification.
The Twin City Amateur Astronomers will have special solar telescopes set up for a public viewing session from 9 a.m.to 1 p.m. on the north unit of Tipton Park, off College Avenue in Bloomington.
The last transit of Mercury occured in November 2006.
Three spacecraft will observe the transit, so if you can’t view it in your own skies, check out the space agency online.
Mercury orbits the sun every 87.97 days, rotating on its axis every 58.65 days. Five months after observing the June 3, 1769, transit of Venus from Tahiti, Cook and Charles Green, the astronomer aboard HMS Endeavour on that voyage, observed a transit of Mercury from New Zealand.
John Pressly, science curator and observatory officer at Coats Observatory in Paisley, Renfrewshire, which will be open from 1pm to 6pm for the event, said: “Mercury is a pretty small place, so it is not going to look huge even through our telescopes”.
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A transiting planet causes a drop in the sun’s brightness.
