Magnificent McNaught.

The brightest comet in 4 decades is flaunting its dusty tail over southern skies, as this Jan. 18 photograph taken from Dunedin, New Zealand, attests. When Comet McNaught was discovered in August 2006, orbital computations suggested that it was a first-time visitor to the inner solar system from far beyond Pluto. Given the lackluster performance of other presumed first timers, "it was difficult to summon much enthusiasm" for McNaught, says Brian Marsden of the Harvard-Smithsonian Center for Astrophysics in Cambridge, Mass. Even after an impressive show over northern skies around Jan. 12, when the comet passed nearest the sun, "we still had no inkling of its impending display" that has since wowed southern sky watchers, he adds.