Why does Mercury present the greatest challenge for skywatchers hoping to spot it in the western sky?
Answer
It never strays far from the Sun's glare.
Mercury poses the greatest difficulty for observers seeking it in the evening sky because, as the innermost planet orbiting the Sun, it is severely constrained by the Sun's brightness. It is physically impossible for Mercury to appear far from the Sun in the sky, meaning it is visible only very low on the eastern horizon just before sunrise or, conversely, very low in the western sky immediately following sunset. Its viewing window is often very brief, usually lasting only a short time after twilight begins before it sets, and it can be completely invisible for many weeks or months while it is too close to the Sun to be seen.
Related Questions
If a dazzlingly bright object shines low in the west after sunset, what planet is it almost certainly?What is the most reliable indicator for distinguishing a planet from a star when viewing objects in the west?What feature might observers spot by using modest binoculars when viewing Jupiter in the western sky?Why does Mercury present the greatest challenge for skywatchers hoping to spot it in the western sky?What distinct color is associated with the planet Mars when visible as a star-like object in the west?What unique structural feature observable in telescopes makes observing Saturn particularly rewarding?What celestial condition defines a planet as an "evening object" visible in the western sky shortly after sunset?What apparent path does the Sun take across our sky throughout the year, which planets orbit relatively close to?When attempting to view Jupiter or Saturn in the western sky, why is setting a second viewing window 45 to 60 minutes after sunset recommended?Why are Mars and Saturn generally less prominent visitors to the post-sunset western sky compared to Venus and Jupiter?