>> and we'll introduce you to this year's cnn hero of the year. shirley, how she plans to continue her important work with the homeless and less fortunate in the year ahead. all that and more, let's get you caught up on this morning's top stories. thanks so much to boris and amara. good morning, and merry christmas to you. i'm jessica dean in washington. the omicron covid surge is making holiday travel a headache for a lot of people today. both delta and united flight cancellations are in the triple digits for the second straight day. delta canceled 268 flights while united at 196 cancellations. jetblue canceled 120 flights. the airlines are blaming staffing shortages stemming from the omicron variant. they want the cdc to cut the isolation period in half for employees who develop breakthrough cases from ten days down to five. nasa will attempt to launch