WORTH NOTING ON TV

THURSDAY Twelfth Night (A&E cable, 9-11 p.m.): The magic of the Bard's comedy is worked by a brilliant, fascinatingly diverse British cast: Ralph Richardson as Sir Toby Belch, Alec Guiness as Malvolio, Tommy Steele as the clown, John Moffatt as Sir Andrew Aguecheek, and - in an intriguing twist - Joan Plowright as both Viola and her twin brother, Sebastian. FRIDAY Life on Ice: Antarctica and Mars (PBS, 10-11 p.m.): Did life once flourish on Antarctica? And if it did, might it not also have thrived on Mars, since they are so similar? This documentary follows research by scientists in both places and reveals how the frozen continent may hold secrets about life on the faraway planet.

SATURDAY Cops in Minneapolis (Fox, 9-9:30): TV's true ``reality'' show - with no reenactments and no fudging - opens its season in a once fairly low-crime city. In a format change the series really doesn't need, each documentary now has a ``theme'' - like ``rookies'' ``female officers'' - but it's still the most honest and least hokie program in this increasingly popular genre.

SUNDAY Survivors (A&E cable, 8-9 p.m.): First of three shows that traces the impact of humans on the natural world by giving a ``voice'' to living things - a kangaroo, a mahogany tree, a fur seal. This special takes the truly long view, from early man as a hunter and fisher to modern issues of population growth and conservation.

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