The After-Dark Gathering
Venus, Jupiter and Mercury are aligning in the west
The moon is at first-quarter Thursday the 16th, when it appears high in the southwest at sunset and sets around 1am. Over the next week it shifts roughly 10 degrees to the east at sunset each night, until on the 23rd, the night of full moon, it rises as the sun sets and sets the next morning as the sun rises.
Along the way Luna makes some notable pairings. Saturday night you’ll find it trailing less than five degrees behind first-magnitude Regulus, the heart of Leo the lion. Tuesday evening the moon joins another stellar luminary, Spica of the constellation Virgo, and as the two arc westward, they draw closer together, until they are just a few degrees apart before setting around 3am Wednesday. That night, the moon appears beside Saturn, and within a couple hours of sunrise they are within four degrees of one another above the west horizon.
Just a few weeks past opposition, Saturn is a stalwart through the night sky, appearing as the brightest star-like object in the southeast at sunset, shining high in the south at midnight and setting in the northwest a little after 4am.
As the sun sets, the first light to emerge is likely to be Jupiter above the west-northwest horizon. Almost twice as bright but lower amid the haze of twilight is Venus. Night by night, Jupiter dips closer to the horizon, while at the same time Venus pulls higher. Watch as these two close the gap by one degree each night, leading to an end-of-month conjunction that will leave them a mere degree apart.
As if two weren’t company enough, Mercury climbs into view around the 19th, lower still in the west-northwest. It is almost as bright as Jupiter, but it is so tight against the horizon that you’re likely to need binoculars to spot it at first. But by the 23rd, it leapfrogs over Venus, forming the middle point in as the three planets align on the 28th.