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                                                                   EXHIBIT 10.21


                                 AMENDMENT NO. 3
                                       TO
                        ORBIMAGE GROUND STATIONS CONTRACT
                            CONTRACT NO. OGS-99-02-01

     AMENDMENT NO. 3 TO ORBIMAGE GROUND STATIONS CONTRACTS NO. OGS-99-02-01 (the
"Amendment") is made and entered into as of the 6th day of October 1999 by and
between MACDONALD, DETTWILER AND ASSOCIATES LTD., a Canadian corporation
("MacDonald Dettwiler"), and Orbital Imaging Corporation, a Delaware corporation
("ORBIMAGE").

                                    RECITALS

     WHEREAS, ORBIMAGE and MacDonald Dettwiler are parties to that certain
ORBIMAGE Ground Stations Contract No. OGS-99-02-01 dated May 26, 1999, pursuant
to which MacDonald Dettwiler has agreed to deliver a series of OGS Systems and
options meeting certain agreed technical and other specifications at an agreed
price, subject to final agreement of the parties with respect to each OGS System
ordered by ORBIMAGE (the "OGS Contract"); and

     WHEREAS, in connection with the OGS Contract, ORBIMAGE must exercise CLIN
0001c, Regional Distributor Software Development NRE, on or before October 6,
1999; and

     WHEREAS, in connection with the NTT Data OGS, MacDonald Dettwiler submitted
to ORBIMAGE that certain Deferral of Warranty Price Proposal Ref. PS99-G-F/0504
dated September 29, 1999 (the "Deferral of Warranty Proposal"), which would
become CLIN 0005a, setting forth MacDonald Dettwiler's proposal to deliver said
Deferral of Warranty solely for the purposes of the NTT Data OGS (the "Deferral
of Warranty"); and

     WHEREAS, ORBIMAGE desires to exercise CLIN 0001c and CLIN 0005a of Exhibit
B of the OGS Contract; and

     WHEREAS, in connection with the delivery of the Regional Distributor
Software Development NRE and the Deferral of Warranty the parties desire to
amend certain provisions of the OGS Contract as set forth herein.

     NOW, THEREFORE, in consideration of the foregoing recitals, the mutual
covenants and agreements contained herein, and for other good and valuable
consideration, the receipt and sufficiency of which are hereby acknowledged, the
parties hereto, intending to be legally bound, agree as follows:



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ARTICLE 1.    ORDER

     (a)      ORBIMAGE hereby exercises CLIN 0001c and 0005a of Exhibit B of the
OGS Contract for the delivery of the Regional Distributor Software Development
NRE and delivery of the Deferral of Warranty. MacDonald Dettwiler hereby
acknowledges the foregoing and agrees to deliver the Regional Distributor
Software Development NRE and delivery of the Deferral of Warranty on the terms
and conditions of the OGS Contract.

     (b)      The FFP amount for CLIN 0005a is [*CONFIDENTIAL TREATMENT
              REQUESTED*]. The total FFP amount payable by ORBIMAGE for the
              delivery of the NTT Data OGS, consisting of CLINs 0005, 0005a,
              0009, 0011 and the OrbView-3 Update is set forth below:

     [*CONFIDENTIAL TREATMENT REQUESTED*]

     (c)      [*CONFIDENTIAL TREATMENT REQUESTED*]


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ARTICLE 2.    AMENDMENTS TO EXHIBIT B OF THE OGS CONTRACT

     (a)      The parties hereby amend the table set forth in Exhibit B, Section
2 of the OGS Contract by deleting said table in its entirety and replacing it
with the following (which amendment incorporates the new CLIN 0001c for the
Regional Distributor Software Development NRE set forth in Article 1(a) above):

[*CONFIDENTIAL TREATMENT REQUESTED*]

ARTICLE 3.    MISCELLANEOUS

     (a)      Except as expressly modified or amended hereby, all of the terms
and conditions of the OGS Contract shall remain in full force and effect.

     (b)      This Amendment may be executed in two or more counterparts, each
of which shall be considered an original and all of which together shall
constitute one and the same instrument.

     IN WITNESS WHEREOF, the parties have caused this Amendment to be executed
as of the date first written above.



                                            
MACDONALD, DETTWILER AND                       ORBITAL IMAGING CORPORATION
ASSOCIATES LTD.



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Signature                                      Signature

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Name                                           Name

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Title                                          Title



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