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                       JEFFERS, WILSON, SHAFF & FALK, LLP
                                ATTORNEYS AT LAW
                             18881 VON KARMAN AVENUE
                                   SUITE 1400
                            IRVINE, CALIFORNIA 92612
                            TELEPHONE: (714) 660-7700
                            FACSIMILE: (714) 660-7799


                                  June 3, 1997


Mr. H. Garrett Thornburg, Jr., Chairman
Thornburg Mortgage Asset Corporation
119 East Marcy Street, Suite 202
Santa Fe, New Mexico 87501

         Re:  Issuance of Shares Pursuant to S-8 Registration Statement

Dear Mr. Thornburg:

         This letter relates to the issuance of up to 800,000 shares of Common
Stock, par value $.01 per share (the "Shares"), of Thornburg Mortgage Asset
Corporation, a Maryland corporation (the "Company"), registered pursuant to
its Registration Statement on Form S-8, filed with the Securities and Exchange
Commission on June 4, 1997 (the "Registration Statement"). You have requested
that we deliver to you an opinion as to whether the Shares will have been duly
authorized, validly issued, and, when issued, will be fully paid and
nonassessable shares of Common Stock of the Company. We have also examined the
Articles of Incorporation, as amended, and such other corporate records,
including the resolutions of the Company's Board of Directors, and such other
documents as we have deemed necessary in order to express the opinion set forth
below. In our examination we have assumed the genuineness of all signatures and
the authenticity of all documents submitted to us as originals and the
conformity of all originals of all documents submitted to us as copies. As to
questions of fact material to such opinion, we have relied upon statements and
representations of the Company.

         Our opinion is based on existing law which is subject to change either
prospectively or retroactively. Relevant laws could change in a manner that
could adversely affect the Company or its stockholders. We have no obligation to
inform the Company of any such change in the law. We have not been requested to
opine, and we have not opined, as to any issues other than those expressly set
forth herein. This opinion extends only to questions relating to the validity of
the Shares offered and sold under the Registration Statement. We express no
opinion with respect to any other issue.

         We are admitted to practice law in the State of California and our
opinion is limited to federal law and the corporate laws of the State of
Maryland that affect such opinion. We express no opinion with respect to any
other law or the laws of any other jurisdiction.



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Thornburg Mortgage Asset Corporation
May 30, 1997
Page 2

         Assuming the Shares are issued and paid for in accordance with the
terms of the offering described in the Registration Statement, including
documents incorporated by reference thereto, and when certificates representing
such Shares have been issued to the purchasers, based on the foregoing, we are
of the opinion that the Shares will have been duly authorized, validly issued,
and will be fully paid and nonassessable shares of Common Stock of the Company.

         For purposes of rendering this opinion we have made such legal and
factual inquiries as we have deemed necessary under the circumstances. Although
we have not independently verified all of the facts relied upon for purposes
hereof, nothing has come to our attention that has led us to believe that the
facts are other than as stated herein or that there exist other material facts
not considered.

         Our Opinion contained herein is solely for the benefit of the Company
and may be relied upon by the Company only in connection with the Registration
Statement. In this regard, we hereby consent to the filing of this opinion,
including this consent, as an exhibit to the Registration Statement.


                                        Very truly yours,

                                        /s/ JEFFERS, WILSON, SHAFF & FALK, LLP
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                                        JEFFERS, WILSON, SHAFF & FALK, LLP