NEW YORK — TCI Satellite Entertainment (TSAT) will make its senior VP of marketing and sales Chris Sophinos acting president until the company becomes absorbed into Primestar, the direct broadcast satellite distributor.The owners of Primestar are the five largest cable operators in the U.S.: Tele-Communications Inc. (37% stake), Time Warner/Newhouse (30%), Media One (formerly Continental) (10%), Comcast (10%) and Cox (9%). The sixth owner, with 4%, is GE American Communications. TSAT ran the Primestar operation for its partners in the 1990s, but after a series of meetings in May and June, the principals decided on a new structure that would turn Primestar into a separately run corporation to include all of the satellite assets of News Corp. and MCI. The six partners say they hope to get approval from key government agencies by the end of the year. Sophinos takes over from Gary Howard, who will stay on as an adviser until the company completes its transition. Howard has already signed a contract to become chairman and CEO of United Video Satellite Group.