These are 5 position alpha-numeric codes comprising the d series. All other level II codes and descriptors are approved and maintained jointly by the alpha-numeric editorial panel (consisting of CMS, the Health Insurance Association of America, and the Blue Cross and Blue Shield Association).
Alaska: Although Alaska enjoys a high volume of aurora activity, its cruises are not often mentioned as northern lights cruises. During the Alaska cruise season, it's rarely dark enough for the lights to be visible.
SEE THE NORTHERN LIGHTS OR AURORA BOREALIS. If you are touring Alaska during the fall, winter, or spring this natural phenomenon is something worth staying up for. Any location with clear dark skies will do but if you are staying in places like the Alyeska Resort you can request a Northern Lights wake up call.