ON AND OFF THE AIR:
* So much for sophistication. Madonna's pale shadow of the late Marilyn Monroe seems more attractive to Baltimore movie viewers than the real thing.
The material girl's awful 1986 film "Shanghai Surprise" greatly out-polled Monroe's sublime "The Seven Year Itch" (from 1955 with Tom Ewell and directed by Billy Wilder) in this week's renewed summer stunt on WNUV-Channel in which viewers get to choose between two movies.
The option is offered for Monday's 8 p.m. movie each week, and voting takes place by calling a telephone number for the movie you want.
Each choice is being promoted with a cute "either/or" campaign. "Madonna or Marilyn?" asked promotions this week, and the station's Bruce Binenfeld says about 70 percent of the more than 4,000 phone votes went for the Madonna bomb. He notes the system allows unlimited multiple voting.
Next Monday's choice stretches the quality vs. shlock choice even further, with "Swanson or Bronson?" The choice is between the classic "Sunset Boulevard" with Gloria Swanson and William Holden, or "The Mechanic" with Charles Bronson.
* Speaking of Channel 54 movies, if the current theatrical "Aliens 3" has somehow left you wondering about the beginning of this trilogy, the original "Alien" from 1979 can be seen at 8 tonight.
Even on a small screen and with commercials, the movie directed by Ridley Scott generates great tension, as an acid-drooling creature stalks the occupants of a survey spaceship.
* Baltimore's United Artists Cable system and Baltimore County's Comcast Cablevision this weekend join with the National Aquarium to help promote another run of "Shark Week," the annual summer screening of a variety of documentaries and other films about sharks by The Discovery Channel.
The programming begins Sunday night. Thus tomorrow has been named Shark Day at the aquarium, with special events from 9 a.m. to 5 p.m., including face painting, prize giveaways and a chance for kids to meet a strolling land shark. The aquarium's own collection of real finny predators will be on view inside, too.
For information, call 986-044.
* Can't wait for next week's Democratic National Convention? CNN's pre-convention coverage is scheduled to begin this weekend, starting with an edition of "Inside Politics '92" from Madison Square Garden at 4:30 p.m. today.
And a special "Larry King Live" is scheduled from the convention hall at 9 p.m. Sunday on the cable news network.
* Can't name even one of the current crop of young golfers on the pro circuit? Then go back to the days when Jack Nicklaus, Arnold Palmer and Chi Chi Rodriquez frequently led the pack.
ABC offers coverage Saturday and Sunday (3:30 p.m. both days) of the "U.S. Senior Open" live from the Saucon Valley Country Club in Bethlehem, Pa.