XM RADIO ESTABLISHES PROGRAM DEVELOPMENT UNIT: "XM ORIGINALS" TO CREATE RADIO PROGRAMMING FOR THE NEXT MILLENNIUM

XM Also Adds The NewsHour with Jim Lehrer and The Sporting News As Content Providers

National, August 10, 1999 -- XM Satellite Radio today announced the creation of "XM Originals," an in-house programming unit established to create provocative, original radio programming formats for the company's satellite radio service.

XM Radio also announced additional content providers that will contribute to or develop programming for XM Originals, including The NewsHour with Jim Lehrer, Public Broadcasting Service's leading daily news show, and The Sporting News, a leading sports magazine. XM Originals has also hired composer Larry Fast to compose unique audio signatures for XM. Fast is best known for his work with Barbra Streisand, Peter Gabriel and others. XM Originals is currently developing a channel with USA TODAY, among others.

In making the announcement, XM Satellite Radio's President and CEO, Hugh Panero, said: "We believe that the quality and diversity of our programming will be key drivers of consumer interest in our service. To that end, we have developed a unique programming strategy that offers consumers original music and talk channels created by the company as well as channels created by brand-name content providers."

Utilizing a large portion of its up to 100 channels, XM Originals will revitalize and more extensively focus on popular music genres, such as oldies, rock and country, as well as create innovative formats, including jazz, blues, reggae and pop classical. XM Originals formats will include artists with strong music sales and concert revenues who get little airplay on traditional AM/FM radio stations. XM also intends to brand individual channels by creating channel-specific names, personalities and images using compelling on-air talent and other techniques to attract target market segments. XM Originals will nurture the DJs and PDs of the 21st century. It will be spearheaded by Lee Abrams, XM Radio's Senior Vice President of Programming and Content, and Dave Logan, XM Vice President of Programming Operations, who have a proven track record designing, operating and launching new radio formats.

The NewsHour with Jim Lehrer

PBS's NewsHour with Jim Lehrer will air each weekday night on the XM Originals channel. The NewsHour with Jim Lehrer, which is broadcast on more than 300 PBS stations nationally and by satellite throughout much of the world, has been recognized as the "most objective," news organization in America and as the "most reliable" source of television news. The NewsHour has earned more than 80 awards for outstanding reporting, including many of journalism's highest honors.

The Sporting News

The Sporting News (TSN) will provide up-to-the-minute reports often live on location as part of XM's One-On-One Sports Channel. Published continuously since 1886, The Sporting News is the only weekly magazine to cover professional baseball, football, basketball, hockey, college football and basketball 52 weeks a year. Expert analysis, perspective, opinion and statistics allow TSN readers to "see a different game." TSN is published by Time Mirror Magazines, one of the nation's leading publishers of special-interest, leisure-oriented magazines, read by more than 60 million people each month. TSN's website (a href="http://www.sportingnews.com">www.sportingnews.com) continues to be recognized as one of the best sports sites on the Internet.

Larry Fast, Composer

XM is looking to a variety of talented artists to make its multi-channel vision a reality. Larry Fast, the renowned composer, producer, instrument designer and electronic music trailblazer is composing unique audio signatures and sonics for XM. He is best known for his series of pioneering electronic music albums recorded under the project name Synergy. He is also known for his work with Peter Gabriel, playing synthesizer on records, on tour and rounding out the production team for nearly a decade. Fast has worked -- as musician, composer or producer -- with an endless stream of world-class artists and producers: Hall & Oates, Foreigner, Bon Jovi's Richie Sambora and David Bryan, Barbara Streisand, Annie Haslam's Renaissance, Randy Newman, Joan Armatrading, Meat Loaf and many others. Among other accolades, Mr. Fast has been the recipient of Keyboard Magazine's annual award for Best Synthesist.

XM Satellite Radio

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 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 only two satellite digital audio radio service 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.