article by Joe Rao (Hayden Planetarium, NY City):
Just wait until it gets sufficiently dark — say about one hour after sunset. Look about one-third of the way up from the horizon to the point directly overhead (called the zenith) and you'll see the moon. Most people will think it's a "full" moon, but that won't happen until late Friday night. The moon actually will be 94-percent illuminated.
Then look off to the left of the moon and a bit above it for a bright, non-twinkling star shining with a whitish-yellow glow. That will be Saturn.
Of course, from our Earthly vantage point, we know that the moon is much closer to us than Saturn. In fact, it's 3,673 times closer to be precise. On Wednesday, the moon will be 225,400 miles (363,000 km) away compared to 828 million miles (1.33 billion km) to Saturn. As such, the moon appears to move much more quickly against the background stars compared to Saturn. During the course of one hour, the moon moves to the east by roughly its own apparent diameter (about one-half degree).
That's why during the overnight hours of Wednesday night to Thursday morning, the moon's position relative to Saturn will noticeably change. By 1:30 a.m. local daylight time — if you're still awake — look toward the southwest sky for the moon and Saturn. The direction you'll need to face by then will have changed thanks to the rotation of the Earth.
But notice also that the moon's position relative to Saturn has changed; now Saturn is not to the moon's left, but soaring almost directly above it. That's because the moon will have moved about 2 degrees — four moon widths — to the east of Saturn over that four-hour time frame.
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