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                                                                  EXHIBIT 10.121

              SECOND AMENDMENT TO FINANCING AND SECURITY AGREEMENT
              ----------------------------------------------------

     THIS SECOND AMENDMENT TO FINANCING AND SECURITY AGREEMENT (this
"Agreement") is made as of the 26th day of September, 2003, by SPACEHAB,
INCORPORATED, a corporation organized under the laws of the State of Washington,
SPACEHAB GOVERNMENT SERVICES, INCORPORATED, formerly known as Johnson
Engineering Corporation, a corporation organized under the laws of the State of
Colorado, ASTROTECH SPACE OPERATIONS, INC., a corporation organized under the
laws of the State of Delaware, jointly and severally (each a "Borrower" and
collectively, the "Borrowers"); and RIGGS BANK N.A., a national banking
association ("Lender").

                                    RECITALS
                                    --------

     A.   The Borrowers and the Lender entered into a Financing and Security
Agreement dated August 29, 2002, as modified by a First Amendment to Financing
Agreement dated May 13, 2003 (the same, as amended, modified, substituted,
extended, and renewed from time to time, collectively, the "Financing
Agreement").

     B.   The Financing Agreement provides for some of the agreements between
the Borrowers and the Lender with respect to the "Loans" (as defined in the
Financing Agreement), including a revolving credit facility in an amount not to
exceed $5,000,000.

     C.   The loss of the Space Shuttle Columbia has had a negative impact on
the financial condition of the Borrowers.

     D.   The Lender and the Borrowers have agreed to revise certain financial
covenants, cash secure the Obligations and suspend requirements related to the
Borrowing Base and desire to execute this Agreement to evidence these
agreements.

                                   AGREEMENTS
                                   ----------

     NOW, THEREFORE, in consideration of the premises and for other good and
valuable consideration, receipt of which is hereby acknowledged, the Borrowers
and the Lender agree as follows:

     1.   The Borrowers and the Lender agree that the Recitals above are a part
of this Agreement. Unless otherwise expressly defined in this Agreement, terms
defined in the Financing Agreement shall have the same meaning under this
Agreement.

     2.   The Borrowers and the Lender agree that on the date hereof the
aggregate outstanding principal balance under the Revolving Credit Note (subject
to change for returned items and other adjustments made in the ordinary course
of business) is $450,000.00.

     3.   Each of the Borrowers represents and warrants to the Lender as
follows:

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          (a)  It is duly organized, and validly existing and in good standing
under the laws of the jurisdiction of its formation and is duly qualified to do
business as a foreign corporation in good standing in every other jurisdiction
wherein the conduct of its business or the ownership of its property requires
such qualification;

          (b)  It has the power and authority to execute and deliver this
Agreement and perform its obligations hereunder and has taken all necessary and
appropriate action to authorize the execution, delivery and performance of this
Agreement;

          (c)  The Financing Agreement, as heretofore amended and as amended by
this Agreement, and each of the other Financing Documents remains in full force
and effect, and each constitutes the valid and legally binding obligation of
Borrower, enforceable in accordance with its terms;

          (d)  All of Borrower's representations and warranties contained in the
Financing Agreement and the other Financing Documents are true and correct on
and as of the date of Borrower's execution of this Agreement; and

          (e)  No Event of Default and no event which, with notice, lapse of
time or both would constitute an Event of Default, has occurred and is
continuing under the Financing Agreement or the other Financing Documents which
has not been waived in writing by the Lender.

     4.   The Financing Agreement is hereby amended as follows:

          (a)  Section 1.1 (Certain Defined Terms) is modified by restating the
following defined term:

          "Financing Documents" means at any time collectively this Agreement,
     the Pledge Agreement, the Notes, the Security Documents, the Letter of
     Credit Documents, and any other instrument, agreement or document
     previously, simultaneously or hereafter executed and delivered by any
     Borrower and/or any other Person, singly or jointly with another Person or
     Persons, evidencing, securing, guarantying or in connection with this
     Agreement, any Note, any of the Security Documents, any of the Facilities,
     and/or any of the Obligations.

          (b) Section 1.1 (Certain Defined Terms) is modified by adding the
following defined term:

          "Pledge Agreement" means the Collateral Security Agreement dated
     September 26, 2003 executed by SpaceHab Incorporated in favor of Lender, as
     amended, modified, substituted, extended, and renewed from time to time."

          (c) The second paragraph of Section 2.1.1 (Revolving Credit Facility)
is hereby deleted and the following is inserted in place thereof:

          "During the Revolving Credit Commitment Period, the Lender agrees to
     make advances under the Revolving Credit requested by the Company from time

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     to time provided that after giving effect to the Company's request, the sum
     of (a) the outstanding principal balance of the Revolving Credit and (b)
     the Letter of Credit Obligations would not exceed the Revolving Credit
     Committed Amount."

          (d)  Sections 2.1.3 (Borrowing Base) and 2.1.4 (Borrowing Base Report)
are hereby deleted in their entirety. The defined terms Borrowing Base,
Borrowing Base Deficiency and Borrowing Base Report shall be deemed deleted in
their entirety and the Financing Agreement shall be read as those all references
thereto had been deleted.

          (e)  Section 6.1.1(e) (Monthly Statements and Certificates) is hereby
deleted in its entirety.

          (f)  Section 6.1.15 (Financial Covenants) is modified by deleting
subsections (a), (b) and (c) in their entirety.

          (g)  Section 6.1.15(e) (Liquidity Covenant) is deleted in its entirety
and the following section is inserted in its place:

          "(e) Liquidity Covenant. The Company and its Subsidiaries will at all
     times maintain Liquid Assets of not less than $5,600,000 on deposit with
     the Lender or any of its Subsidiaries or Affiliates."

     5.   The Lender hereby waives defaults under Section 6.1.15(a) (Tangible
Capital Funds), Section 6.1.15(b) (Leverage Ratio) and Section 6.1.15(c) (Debt
Service Coverage Ratio) as of June 30, 2003; provided, however, that this
Section shall not be deemed to waive any defaults under such sections after the
date of this Agreement or after the period stated, or any other defaults arising
out of non-compliance by the Borrowers with the Financing Agreement, whether or
not the events, facts or circumstances giving rise to such non-compliance
existed on or prior to the date hereof.

     6.   Each of the Borrowers hereby issues, ratifies and confirms the
representations, warranties and covenants contained in the Financing Agreement,
as amended hereby. The Borrowers agree that this Agreement is not intended to
and shall not cause a novation with respect to any or all of the Obligations.

     7.   The Borrowers acknowledge and warrant that the Lender has acted in
good faith and has conducted in a commercially reasonable manner its
relationships with the Borrowers in connection with this Agreement and generally
in connection with the Financing Agreement and the Obligations, the Borrowers
hereby waiving and releasing any claims to the contrary.

     8.   The Borrowers shall pay at the time this Agreement is executed and
delivered all fees, commissions, costs, charges, taxes and other expenses
incurred by the Lender and its counsel in connection with this Agreement,
including, but not limited to, reasonable fees and expenses of the Lender's
counsel and all recording fees, taxes and charges.

     9.   This Agreement may be executed in any number of duplicate originals or
counterparts, each of such duplicate originals or counterparts shall be deemed
to be an original and all taken together shall constitute but one and the same
instrument. The Borrowers agree

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that the Lender may rely on a telecopy of any signature of the Borrowers. The
Lender agrees that the Borrowers may rely on a telecopy of this Agreement
executed by the Lender.

     IN WITNESS WHEREOF, the Borrowers and the Lender have executed this
Agreement under seal as of the date and year first written above.


WITNESS OR ATTEST:                      SPACEHAB, INCORPORATED


                                        By: /s/ Julia A. Pulzone          (Seal)
------------------------------             -------------------------------
                                            Name: Julia A. Pulzone
                                            Title: Chief Financial Officer


WITNESS OR ATTEST                       SPACEHAB GOVERNMENT SERVICES,
                                        INCORPORATED, formerly known as Johnson
                                        Engineering Corporation


                                        By: /s/ Julia A. Pulzone          (Seal)
------------------------------             -------------------------------
                                            Name: Julia A. Pulzone
                                            Title: Chief Financial Officer


WITNESS OR ATTEST:                      ASTROTECH SPACE OPERATIONS, INC.


                                        By: /s/ Julia A. Pulzone          (Seal)
------------------------------             -------------------------------
                                            Name: Julia A. Pulzone
                                            Title: Chief Financial Officer


WITNESS:                                RIGGS BANK N.A.


                                        By: /s/ Douglas T. Brown          (SEAL)
------------------------------             -------------------------------
                                            Douglas T. Brown
                                            Group Vice President

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