• As seen from Earth, the moon looks much larger than Jupiter. But Jupiter is actually much bigger than our moon. The moon only appears bigger, because it's so much closer to us. This evening, the moon is about 1/372 of an Astronomical Unit or A.U. away, with one A.U. equally one Earth-sun dis

tance. Meanwhile, Jupiter resides about 4.5 astronomical units from Earth. That places Jupiter well over 1,600 times farther away than tonight's moon.
• Jupiter's diameter is about 40 times greater than our moon's diameter. To gauge the size of our moon relative to Jupiter, look at Jupiter though a backyard telescope sometime. Jupiter's four major moons - called the Galilean moons - are pretty easy to see. You might miss a moon or two on occasion, because these moons routinely swing in front and in back of Jupiter. In their outward order from Jupiter, these moons are Io, Europa, Ganymede and Callisto. Io and Europa are about the same size as our moon, whereas Ganymede and Callisto have diameters of about 1.5 times that of our moon.
• More info on observing Jupiter's moons
• Watch for Jupiter and Earth's moon to rise late tonight. The moon will follow Jupiter westward across the sky in the hours between midnight and dawn. If you're an early morning person, look for the moon and Jupiter to shine high in Sunday morning's predawn and dawn sky.
• For binocular astronomers: Dwarf planet Ceres - shown on the chart at the top of this post - is not visible to the eye. In fact, it's several times fainter than the faintest star that you can see on a dark moonless night. In fact, even with a telescope or steadily-held binoculars, you'd probably have a much easier time catching the four major moons of Jupiter than Ceres.
• Sky chart for finding Ceres

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