• A spacecraft is now in route to the dwarf planet Pluto, scheduled to arrive in the year 2015. Tonight's moon can help you visualize this Pluto spacecraft's whereabouts on the sky's dome.
• We're talking about the New Horizons spacecraft, launched from Earth in 2006. Will you see the spacecraft itself tonight? No. Even with a high-powered telescope, this little craft cannot be seen from Earth now as it speeds toward the outer solar system. You'd have a better chance of spotting Pluto, in fact (which can't be seen either, from Earth, with the eye alone). Pluto is some 1,500 times fainter than the faintest star visi

ble to the unaided eye, but Pluto outshines the New Horizons spacecraft by some 10 billion times.
• We label the star cluster M25 on the feature chart, because it's less than one degree from the dwarf planet Pluto on the sky's dome. The width of your little finger at an arm's length measures the approximate angular distance between M25 and Pluto. You can actually see this cluster with the unaided eye on a dark, moonless night.
• So what are we suggesting here? Nothing more than stretching your imagination to visualize a spacecraft speeding along in outer space. Tonight's waxing gibbous moon and the New Horizons spacecraft occupy nearly the same spot on the sky's dome. Of course, the two are not close together in space. The moon lies about

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