Mercury, Venus, Mars, Jupiter, and Saturn are lining up for the first time in almost 18 years. While star gazers may have noticed four of these planets in the nighttime sky over the last few months, the addition of Mercury marks the first time these five celestial bodies are aligning in this order since December 2004. The best viewing will be at night right before dawn. To view this interplanetary event, look east, where you will find Mercury hugging the horizon. Venus will be huddled right next to it, with Mars and Jupiter huddled together in the ESE sky. The arc is completed by Saturn even higher in the SSE sky. Peak viewing occurs on the morning of June 16th about 45 minutes before sunrise, with Mercury reaching its highest point above the horizon. June 24th offers another special viewing opportunity. A waning crescent moon will position itself along the same arc of planets, lining up between Venus and Mars. The five-planet alignment (six if you count Earth) will continue to be visible until early July. That’s when Mercury disappears below the horizon. 5 planets are lined up for you to see at dawn this month : NPR