Over the next several days the viewing action will be toward the western horizon around sunset local time. Both inner planets Mercury and Venus are bright and easily seen over the western horizon. Joining them is the heart of Leo the Lion, the star Regulus. As this animated graphic is showing Regulus sets earlier each day and as it does so it is in conjunction with Mercury on July 30th and then further west with Venus on August 3rd.
Regulus is not actually moving toward the west but its changing position relative to the planets and the horizon is the result of the Earth moving nearly 1o each day toward the east. Watch the slideshow and you will notice this westward drifting or apparent motion of the sky resulting from Earth orbiting the Sun. Celestial objects like Regulus do not get closer to the Sun – but rather it is the Sun’s apparent motion toward the east allowing the Sun to catch up with and then pass the celestial object.
As an added viewing bonus the waxing crescent Moon appears and daily the Moon moves toward the east passing by Mercury and then Jupiter a couple of days later.