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Right In the Bull’s Eye

Watch the moon occult Aldebaran

As the sun sets, the hourglass shape of the great hunter Orion is already well positioned in the southeast. His foot, blue-white Rigel, is to the lower right, while his shoulder, red-orange Betelgeuse, is at the opposite corner to the upper left. The three stars of Orion’s belt point almost straight up from the horizon, and following them up and to the right leads you to Taurus the bull.
    Most prominent in Taurus is its fiery eye, the orange-red star Aldebaran. From there look for the bull’s face, marked by the V-shaped Hyades star cluster. Aldebaran is at one leg of the V, although not itself a part of the Hyades. Higher to the right marking the bull’s shoulder is the Pleiades Cluster.
    Monday the waxing gibbous moon sits at one point of a triangle with Aldebaran and the Pleiades, although you may be hard-pressed to spot the cluster against the glare of the moon.
    Tuesday after sunset look for the moon just right of Aldebaran and the Hyades Cluster. Then, just before 9:30, watch as the moon passes over the bull’s fiery eye, occulting it from view for almost an hour.
    In the hour before sunrise, clear skies in the southeast should allow you to see the four naked-eye planets currently visible. Closest to the horizon are Venus and Saturn. There should be no mistaking Venus, blazing at –4 magnitude. Saturn, roughly 10 degrees higher, is more than 60 times dimmer at magnitude +0.5. Don’t confuse Saturn with the nearby star Antares; the ringed planet shines with a steady yellowish glow, while the not-quite-so-bright star twinkles with a red hue. Antares, Saturn and Venus do, however, form a nice triangle.
    Imagine a line from Venus to Saturn, and extend it another 20 degrees or so to find Mars and farther still for Jupiter. Mars is not as bright as Saturn, while Jupiter is the next-brightest starlike object after Venus. You should be able to tell both from blue-white Spica a dozen degrees above Mars.
    You might be able to spot the last the naked-eye planet, Mercury, as early as Wednesday if you’re lucky. It will be even lower than Venus in the glow of the coming sun. You’ll likely need to scour the horizon with binoculars to first see this fleeting planet, which will present an easier target next week.