Exhibit 99.1
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                          AMENDMENT TO RIGHTS AGREEMENT

         AMENDMENT, dated as of July 30, 2003 (this "Amendment"), by and between
SIRIUS SATELLITE RADIO INC. (formerly known as CD Radio Inc.), a Delaware
corporation (the "Company"), and THE BANK OF NEW YORK, a New York corporation
(the "Rights Agent"). Capitalized terms used and not defined herein shall have
the meanings assigned to them in the Rights Agreement.

                                    RECITALS

         WHEREAS, the Company and the Rights Agent are parties to a Rights
Agreement, dated as of October 22, 1997 (as heretofore amended, the "Rights
Agreement");

         WHEREAS, the Company and the Rights Agent desire to amend the Rights
Agreement to extend the Final Expiration Date of the exercise of the Rights from
August 1, 2003 to January 15, 2004;

         WHEREAS, the Board of Directors of the Company deems it desirable and
in the best interests of the Company and its stockholders to amend the Rights
Agreement to extend the Final Expiration Date to January 15, 2004;

         Accordingly, the parties agree as follows:

         1. Amendment of Section 7(a) of the Rights Agreement. Section 7(a) of
the Rights Agreement is hereby amended by deleting the date "August 1, 2003" in
the ninth line thereof and replacing it with "January 15, 2004".

         2. Miscellaneous. This Amendment shall be deemed to be a contract made
under the laws of the State of Delaware and for all purposes shall be governed
by and construed in accordance with the laws of such state applicable to
contracts to be made and performed entirely within such state. This Amendment
may be executed in any number of counterparts, each of such counterparts shall
for all purposes be deemed to be an original, and all such counterparts shall
together constitute but one and the same instrument. If any provision, covenant
or restriction of this Amendment is held by a court of competent jurisdiction or
other authority to be invalid, illegal or unenforceable, the remainder of the
terms, provisions, covenants and restrictions of this Amendment shall remain in
full force and effect and shall in no way be effected, impaired or invalidated.

                            (Signature page follows)








         EXECUTED as of the date set forth above.

                                       SIRIUS SATELLITE RADIO INC.

                                       By:/s/ Patrick L. Donnelly
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                                              Patrick L. Donnelly
                                              Executive Vice President, General
                                              Counsel and Secretary

                                       THE BANK OF NEW YORK

                                       By:/s/ Alexander Pabon
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                                              Alexander Pabon

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