“Titanic” director James Cameron’s “Avatar,” a 3-D extravaganza hyped as a giant leap in cinematic prowess, earned an estimated $73 million during its first weekend at the North American box office, distributor 20th Century Fox said yesterday.

 

The opening for the costly sci-fi film fell short of industry forecasts in the $85 million range. But the News Corp. unit said the tally beat its internal projections, and noted that an enormous snow storm along the East Coast crippled business for all movies.

 

The weekend haul ranks as merely the sixth-biggest of the year in the United States and Canada.