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              AMENDMENT NO. 1 TO STOCK PURCHASE AGREEMENT

      This Amendment No. 1 to Stock Purchase Agreement (the
"Amendment") between Orbital Sciences Corporation ("Orbital") and
Orbital Imaging Corporation (the "Company") is entered into as of the
30th day of March, 2000.

                               RECITALS

      WHEREAS, the parties have entered into that certain Stock
Purchase Agreement as of October 26, 1999 (the "Agreement") pursuant
to which Orbital agreed to purchase Common Shares (as defined
therein) to be issued by the Company.

      WHEREAS, the parties desire to amend the Agreement as set forth
below.

      NOW, THEREFORE, in consideration of the mutual covenants and
agreements set forth herein and for good and valuable consideration,
the receipt and adequacy of which is hereby acknowledged, the parties
hereby agree as follows:

      1.   Definitions.   Unless otherwise defined herein, all
capitalized terms herein shall have the meaning assigned to them in
the Agreement.

      2.   Amendment to Article 2.

           (a)  The parties hereby amend the Agreement by deleting
      Section 2.2(a) in its entirety and substituting the following in
      its place:

                "(a) Purchase.  Upon the terms and subject to the
           conditions herein contained, at the Closing (as defined
           herein) on the Closing Date (as defined herein), the
           Company agrees that it will issue and sell to the
           Purchaser, and the Purchaser agrees that it will acquire
           and purchase from the Company, at least 250,000 Common
           Shares.  The purchase price of the Common Shares shall be
           $10.00 per share (the "Per Share Purchase Price").  Except
           as provided below, the Company shall not be obligated to
           sell and the Purchaser shall not be obligated to purchase
           more than an aggregate of 1,250,000 Common Shares.

                     (i)  Notwithstanding the foregoing, in the event
                that the OrbView-4 satellite has not been launched by
                January 31, 2001, then Orbital's obligation to
                purchase Common Shares hereunder shall increase by
                200,000 Common Shares per month thereafter until
                either the OrbView-3 or OrbView-4 satellite has been
                launched; provided however, that under no
                circumstances shall the Company be obligated to sell
                nor shall the Purchaser be obligated to purchase more
                than an aggregate of 2,500,000 Common Shares under
                this Agreement.


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                     (ii) For purposes of this Section 2.2(a),
                Orbital shall not be deemed to have failed to launch
                either the OrbView-3 or OrbView-4 Satellites, as the
                case may be, if such failure is the result of an act
                of God, the public enemy, embargo, governmental act,
                fire, accident, war, riot, strikes, inclement weather
                or other cause of a similar nature that is beyond the
                control of Orbital, including a decision by ORBIMAGE
                not to proceed with launch (other than an ORBIMAGE
                decision not to proceed with launch that can be shown
                to be attributable to Orbital's performance or to have
                been within its control or due to its fault or
                negligence as described in Section 14.3 of the Amended
                and Restated OrbView System Procurement Agreement
                between the parties).  In such event, Orbital and
                ORBIMAGE shall agree in good faith to a new launch
                date to occur as soon as possible after the end of
                such event.  If the applicable satellite has not been
                successfully launched by such rescheduled date, then
                Orbital's obligation to purchase additional Common
                Shares shall commence to increase as described in
                Section 2.2(a)(i) above."

           (b)  The parties hereby amend Section 2.2(c) of the
Agreement by deleting the third sentence thereof in its entirety and
inserting the following in its place:

                "Upon receipt of the Purchase Event Notice, the
           Purchaser shall elect to purchase Common Shares in an
           amount not less than 250,000 shares and not more than an
           aggregate of 1,250,000 shares (as such number may be
           adjusted pursuant to Section 2.2(a) of this Agreement)
           (including Common Shares previously purchased pursuant to
           this Agreement, if any) (the "Election Amount Notice")."

           (c)  The parties hereby amend the Agreement by deleting
Section 2.2(e) in its entirety and substituting the following in its
place:

                     "(e) Additional Financings and Series A
           Preemptive Rights.  The Company shall use reasonable
           commercial efforts to consummate one or more financings
           through the issuance of equity or debt securities of the
           Company.  The Purchaser's obligation to purchase Common
           Shares pursuant to Section 2.2(b) shall be reduced on a
           dollar for dollar basis by the net proceeds raised by the
           Company in any such financing.  Furthermore, to the extent
           that any holders of the Company's Series A Preferred Stock
           exercise their preemptive rights pursuant to Section 4.1 of
           the Stockholders Agreement with respect to any Purchase
           Event, the Purchaser's obligations to purchase Common
           Shares pursuant to Section 2.2(a) shall be reduced
           proportionately."

 3.   No Further Changes.

      Except as modified by this Amendment, the Stock Purchase
Agreement remains unmodified and in full force and effect.


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IN WITNESS WHEREOF, the parties have caused this Amendment No. 1 to
the Stock Purchase Agreement to be executed as of the date first
written above.

ORBITAL SCIENCES CORPORATION



By:   /s/ James R. Thompson
      -------------------------------------
      James R. Thompson
      President and Chief Operating Officer


ORBITAL IMAGING CORPORATION


By:   /s/ Armand D. Mancini
      -------------------------------------
      Armand D. Mancini
      Vice President and Chief Financial Officer