"Observers will see an eye-catching grouping of three bright objects that includes Venus, the brightest planet; Jupiter, the second brightest planet [as seen from Earth]; and the waning crescent moon—all against a rich backdrop of stars," said Anthony Cook, astronomer at the Griffith Observatory in Los Angeles.

Already dominating the early morning skies for the past month, Venus and Jupiter on July 15 will form a spectacular wide triangle formation with a thin sliver of the moon. (Get more night-sky news.)

The so-called conjunction—when celestial objects appear to get close to each other in the sky—isn't considered rare, since both planets and the moon follow the same pathway in Earth's sky, known as the ecliptic.

"Venus and Jupiter appear near each other about