Today Mercury will be at maximum western elongation, as high in the morning sky as it will appear for this current apparition. After today the planet will slide back into the dawn, passing through superior conjunction on October 8th to reappear in the evening sky around the end of the month.
Mercury typically completes three morning and three evening apparitions in each year. While the innermost planet never gets very far from the Sun, maximum elongation represents the best time to observe Mercury as high in the sky as possible.
There are no transits of Mercury in 2017, the next will be Nov 11, 2019.
|Mercury Events for 2017|
|Maximum Elongation||Jan 19||24.1°W||+0.0|
|Superior Conjunction||Mar 6|
|Maximum Elongation||Apr 1||19.0°E||+0.2|
|Inferior Conjunction||Apr 19|
|Maximum Elongation||May 17||25.8°W||+0.7|
|Superior Conjunction||Jun 21|
|Maximum Elongation||Jul 30||27.2°E||+0.6|
|Inferior Conjunction||Aug 26|
|Maximum Elongation||Sep 12||17.9°W||-0.1|
|Superior Conjunction||Oct 8|
|Maximum Elongation||Nov 24||22.0°E||-0.1|
|Inferior Conjunction||Dec 12|
|Source: NASA Sky Calendar and the Mercury Chaser’s Calculator|