Mercury’s twilight show: Catch the greatest eastern elongation tonight for primetime viewing

Earth’s planetary neighbor will be more visible to the naked eye after sunset on Monday. Here’s what planet watchers need to know.

Those with knowledge of astrology are familiar with the phrase “Mercury is in retrograde.” Perhaps a lesser known Mercury phenomenon is its greatest elongation east. This will occur in the evening sky tonight (Monday, July 22), making Mercury easier to see with the naked eye after sunset.