WORTH NOTING ON TV

* TONIGHT

Presidential debate (ABC, CBS, NBC, PBS, CNN, C-Span, FOX, check local listings for time.): The second of the televised debates among the three major presidential candidates will be carried live from Richmond, Va. This time there will be a single moderator (ABC's Carole Simpson) and no panel, but questions will be taken from the audience. And just in case you try to form your own impressions about what the candidates have said, many networks will follow up the debates with commentary from house pundits a nd outside experts.

The Pacific Century (PBS, 10-11 p.m.): The 10-part weekly series premiering with this episode - "The Two Coasts of China" - is richly justified, if only because some 1 million Americans now work for companies from the Asia-Pacific area - and because Asia's trade with the US now greatly exceeds Europe's. But there's vastly more to it than that, and this series brings historical sweep and human detail to its almost dauntingly comprehensive look at the area. It tells the epic and often tragic story of Asia' s history and troubled relationship to the West over 150 years, explores Asia's crucial importance today, and considers the region's huge, ineluctable future impact on America.

* MONDAY

Presidential debate (ABC, CBS, NBC, PBS, CNN, C-Span, FOX, 7-8:30 p.m., E.T. check local listings): Third presidential debate, from East Lansing, Mich. A single moderator will preside during the first half, and there will be a panel for the second.

Please check local listings for all programs, especially those on PBS.