The year 2019 is going to be a very interesting year for astronomy enthusiasts. There will be 3 supermoons and 5 eclipses along with yearly meteor showers and oppositions of planets. However, what crowns the astronomy calendar 2019 is the rare Transit of Mercury across the Sun on November 11.
What is transit of Mercury?
The transit of Mercury is a celestial event that takes place when the planet Mercury passes directly between the Sun and a superior planet becoming visible against (and hence obscuring a small portion of) the solar disk. During a transit, Mercury appears as a tiny black dot moving across the disk of the Sun.
The transit of Mercury with respect to Earth is more frequent that the transit of Venus. The former takes place 13 to 14 times in a century in a May or a November.
Transit of Mercury in 2019
On Monday, 2019 November 11, Mercury will transit the Sun for the first time since 2016. Since the tiny planet only covers about 1/194th part of the solar disk, a small telescope with a minimum magnification of 50X will be required. The telescope must be equipped with a solar filter as looking at Sun through the telescope will burn your eyes. There are 5 main events that occur during the transit: Contact I-IV and greatest transit.
Contact I: This is the instant when the planet’s disk is externally tangent to the Sun.
Contact II: The instant when the entire planet’s disk has entered the solar disk. The planet can be seen as a small notch along the solar limb.
Greatest Transit: The instant when the planet is at the centre of its path of transit.
Contact III: At Contact III, the planet reaches the opposite limb and once again is internally tangent to the Sun.
Contact IV: Finally, the transit ends at Contact IV when the planet’s limb is externally tangent to the Sun.
So the whole transit will last about 5 hours and 30 minutes. Now the question is: Where will the transit be visible?
The transit will be widely visible from most of Earth including the Americas, the Atlantic and Pacific Oceans, New Zealand, Europe, Africa and western Asia. None of the transit will be visible from central and eastern Asia, Japan, Indonesia, and Australia.
The transit begins before sunrise for observers in western North America. The transit ends after sunset for Europe, Africa, western Asia, and the Middle East. Regions where the entire transit is visible include eastern North America, Central and South America, and the Atlantic Ocean.
Here is a video of “All Astronomy Events of 2019“