At dusk this evening, have a look toward the west to see a pair of planets that have wildly different brightnesses but are at similar points in their journeys and share a similar story. The planets in question are Venus and Mars. Both are losing ground to encroaching twilight as their respective apparitions wind down and they drift toward conjunctions with the Sun. In the case of the Evening Star, that occurs on August 13th, while the Red Planet holds off until November 18th. However, Mars will become essentially invisible to the naked eye much sooner than that - in the latter part of August. Tonight, the two planets are separated by just 3?°; however, they're worlds apart in brightness - Venus is a -4.7-magnitude beacon while Mars is a 1.7-magnitude ember.
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