Evening twilight is a special time of day. The day’s heat begins to abate, and the sounds begin to soften. The setting Sun paints the sky in brilliant yellow, orange, and red, giving way to shades of blue. A few fireflies may flicker to life, with flashes of distant lightning perhaps adding to the show.
And this evening offers some additional performers: the Moon, two planets, and a bright star. They’re low in the west, and ease into view as the Sun drops farther below the horizon.
The Moon is a thin crescent right now — sunlight illuminates only five percent of the lunar hemisphere that faces our way. The rest of the Moon is visible, though, thanks to earthshine — sunlight reflected off of our own Earth. It will become more obvious as the sky grows darker.
The planet Mercury is just a couple of degrees below the Moon. It can be tough to spot in the glow of twilight, and trees or buildings along the horizon can block it from view. It drops too low to find by the time it gets good and dark, so the viewing window is brief.
The window is much longer for Venus, the brilliant “evening star,” to the upper left of the Moon. It will stay in view until around 10 or 11 o’clock, depending on your location.
And the final member of the quartet lines up between Venus and the Moon, a little closer to Venus. It’s Regulus, the star at the heart of Leo, the lion — shining softly through the fading twilight.
More about the Moon and Venus tomorrow.