LEGENDARY NEW YORK RADIO PERSONALITY, JONATHAN SCHWARTZ, NAMED ARTISTIC COORDINATOR OF XM'S AMERICAN STANDARDS FORMAT

National, August 25, 1999 -- XM Satellite Radio announced today that legendary New York on-air personality, author and music historian Jonathan Schwartz is joining the company's new XM Originals unit as Artistic Coordinator of its American Standards format. Passionately committed to this great music, Schwartz will guide the sound and image of this intrinsically American art form. He will also develop and host several hours of programming each day exclusively for XM, including a daily reprise of his fabled Frank Sinatra Show.

"I am thrilled that XM is committed to making great music and lyrics available to Americans from coast to coast," said Schwartz, the Artistic Director of The Lincoln Center's American Songbook Series. "We hope to appeal to traditional fans and draw in a younger audience that is looking for a fascinating musical adventure and interesting presentation.

"We will focus on artists like Frank Sinatra, Ella Fitzgerald and Count Basie, of course," Schwartz added. "But listeners can also expect a deep and wide-ranging music selection that will celebrate this timeless genre." XM's American Standards programming will range from the music of Irving Berlin and Cole Porter to that of Stephen Sondheim and Leonard Bernstein, from singers Tony Bennett and Peggy Lee to Mandy Patinkin and Joni Mitchell.

Schwartz brings to XM his encyclopedic knowledge and 30 years of experience as an anchor personality at New York's WNEW and WQEW. Often called "the Dean of American pop standards," Schwartz began his career in 1967 as one of the first radio personalities at WNEW-FM, during its heyday as America's leading "progressive" music station. He went on to WNEW-AM, where he created the now legendary The Sunday Show, an eclectic mix of American Popular Standards, classical, rock and roll, and jazz. The Sunday Show and Schwartz's The Sinatra Show have a vast and loyal following. In 1992, he moved his radio programs to WQEW-AM; and both shows can now be heard on New York City's WNYC.

Schwartz has written several works of fiction: Almost Home, Distant States, The Man Who Knew Cary Grant and, most recently, The Paris Concert, which will be published in September 2000. He frequently contributes fiction and non-fiction pieces to Vanity Fair, The Atlantic Monthly, Harpers, New York Magazine, Esquire, Sports Illustrated and The New York Times, among other publications. His columns have appeared regularly in GQ Magazine and The Village Voice. Schwartz is also an accomplished singer and cabaret performer. He has cut three albums, Alone Together, New Sun in the Sky and Anyone Would Love You; and, he appears frequently on New York City's cabaret scene, including engagements at Michael's Pub, Rainbow & Stars, The Ballroom, and Fat Tuesdays. Music correspondent for NBC's Today show, Schwartz's voice, as well, has been heard in a countless number of commercials, including voice-overs for Canada Dry, Chemical Bank, Lipton Soups and Carolina Rice.

XM Satellite Radio, a wholly owned subsidiary of American Mobile Satellite Corporation (NASDAQ: SKYC), is developing a new band of radio. The system will use direct satellite-to-receiver broadcasting technology to provide listeners in their cars and at home with crystal-clear sound seamlessly from coast-to-coast. The subscription service is scheduled to start during the first half of 2001 for $9.95 a month. Through its XM Originals programming unit, XM plans to offer an innovative mix of music, talk, news, sports and children's formats. To complement its original programming, XM has signed programming agreements with a number of premier content providers, including USA TODAY, the BBC World Service, Black Entertainment Television, the Hispanic Broadcasting Corporation (formerly Heftel), Bloomberg News Radio, C-SPAN Radio, CNN/Financial Network, CNN/Sports Illustrated, The Weather Channel and many others.

XM is partnering with industry leaders to build its service. General Motors will distribute and market the XM service in its vehicles; Alpine, Delphi Delco, Pioneer and Sharp will design, manufacture and market AM/FM/XM radios; and Hughes and Alcatel are building XM's satellites, the most powerful commercial satellites ever ordered. XM's investors include industry leaders Clear Channel Communications Inc.; DIRECTV, Inc., a unit of Hughes Electronics Corporation; the General Motors Corporation; and a private investment group comprised of Columbia Capital, Telcom Ventures L.L.C., and Madison Dearborn Partners, which together recently invested $250 million in the company. XM Satellite Radio obtained one of two satellite digital audio radio service (SDARS) licenses from the Federal Communications Commission in October 1997. First there was AM, then FM and soon… XM Satellite Radio. For more information, please visit www.xmradio.com.

Factors that could cause forward-looking statements in this news release to differ materially from actual results are discussed in XM's Registration Statement on Form S-1 (No.333-38619) filed with the Securities and Exchange Commission on July 23, 1999, as the same may be amended, and other periodic filings the company will make with the Securities and Exchange Commission.