Rare celestial event on 11 November 2019: Mercury crosses the sun
October 25, 2019
He is the smallest, the fastest and the closest planet to the Sun: Mercury has many special features to offer. It is also the most difficult planet to observe - you can only see it at dusk or dawn on a few days a year. It is even rarer that Mercury crosses directly over the Sun's disk. Such transits of Mercury only take place every few years, the next one on Monday, 11 November 2019, the next but one only in 2032.
When Mercury transits the solar disk, a kind of mini solar eclipse occurs. Thus at least a small telescope with a solar filter is required to observe the event. Solar eclipse glasses will not show the small Mercury. Therefore it is best to go to a public observatory, if the sky is clear many of them will be open for visitors. If the weather on November 11th allows an observation - clear skies are required - we invite you to observe this event together with us. You will find the HdA team with transportable telescopes on the Neckarwiese in the immediate vicinity of the Theodor Heuss Bridge.
The transit begins exactly at 13:35:29 when Mercury virtually hits the left edge of the Sun. Barely two minutes later it has passed the edge of the Sun and stands as a small black circle in front of the bright solar disk. During this transit, Mercury's path leads almost exactly over the centre of the Sun, and it will comparatively long: Athough Mercury is the fastest planet in the sky, the distance from the edge to the centre of the Sun takes almost three hours: It will not be until 16:20 that Mercury crossed the Sun by half.
This is however very close to sunset in Germany. In Berlin, this is exactly at 16:20; further to the west the Sun does not set until around 5 pm. From the Canary Islands, one can follow the passage of Mercury almost to its end at 19:04. Observers on the east coast of the USA or in Central and South America on the other hand can observe the transit completely.
The exact course of Mercury's transit on November 11, 2019 (times in CET)
Mercury meets the solar disk: 13:35:29
Mercury stands completely in front of the sun: 13:37:10
Mercury has passed half the sun: 16:19:39
Mercury reaches the edge of the sun: 19:02:33
Mercury has left the sun again: 19:04:15
Depending on your location, these times differ by a few seconds.