Nearly Christmas, so time for the annual planetary elongation chart!
A high quality PDF version with much more information can be downloaded here.
The planets shown are Mercury (m), Venus (V), Mars (M), Jupiter (J) and Saturn (S).
This chart shows the positions of each planet relative to the Sun (middle) all through the year. The vertical axis represents the days and months of the year. The diagonal bands represent constellation boundaries. The wavy yellow band is a region close to the Sun in which it would be difficult to observe the planets. The wavy yellow line represents regions of the sky rendered invisible because of the proximity of the Sun. The shape of that wavy line explains, for example, why Mercury is easier to observe in the March evening sky than the July evening sky (even though it is further from the Sun in July). Also, the chart behaves like a game of PacMan; any planets reaching opposition 180 degrees west of the Sun wrap straight over to the evening sky on the far left. Think of this chart as being like an unwrapped cylinder!
Places where the lines intersect are planetary conjunctions --- often beautiful (but not significant) events where the planets appear close together in the sky. There will be several notable conjunctions during the year. Details below.
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Dr Adrian Jannetta. Amateur astronomer, maths teacher and science enthusiast.