EXHIBIT 8.1

                    PAUL, WEISS, RIFKIND, WHARTON & GARRISON
                           1285 Avenue of the Americas
                          New York, New York 10019-6064


                                                               December 18, 1998

CD Radio Inc.
1180 Avenue of the Americas
New York, New York 10036

                                CD Radio Inc. --
                       Registration Statement on Form S-4
                                Registration No.
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Ladies and Gentlemen:

         In connection with the referenced Registration Statement on Form S-4
(the "Registration Statement"), filed with the Securities and Exchange
Commission pursuant to the Securities Act of 1933, as amended (the "Act"), and
the rules and regulations promulgated thereunder (the "Rules"), we have been
requested by CD Radio Inc., a Delaware corporation (the "Company"), to furnish
our opinion as to the matters hereinafter set forth. Capitalized terms used and
not otherwise defined herein have the meaning given them in the Registration
Statement.

         For purposes of our opinion, we have reviewed the Registration
Statement (including the exhibits thereto) and relied upon the description of
the Exchange Offer contained therein. We have also made such other
investigations of fact and law and have examined the originals, or copies
authenticated to our satisfaction, of such other documents, records,
certificates or other instruments as in our judgment are necessary or
appropriate to render the opinion expressed below.

         The opinion set forth below is limited to the Internal Revenue Code of
1986, as amended, administrative rulings, judicial decisions, treasury
regulations and other applicable authorities, all as in effect on the date
hereof. The statutory provisions, regulations, and interpretations upon which
our opinion is based are

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subject to change, and such changes could apply retroactively. Any such change
could affect the continuing validity of the opinion set forth below.

         Based upon and subject to the foregoing, and subject to the
qualifications set forth herein, we hereby confirm that the discussion set forth
in the Registration Statement under the heading "CERTAIN UNITED STATES FEDERAL
INCOME TAX CONSEQUENCES" is our opinion.

         We hereby consent to the filing of this opinion as an exhibit to the
Registration Statement and to the use of our name under the heading "LEGAL
COUNSEL" in the prospectus included in the Registration Statement. In giving
this consent, we do not hereby admit that we come within the category of persons
whose consent is required by the Act or the Rules.


                                    Very truly yours,


                                    /s/ PAUL, WEISS, RIFKIND, WHARTON & GARRISON
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                                    PAUL, WEISS, RIFKIND, WHARTON & GARRISON