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                                                                   Exhibit 10.9a


                       AMENDMENT TO EMPLOYMENT AGREEMENT

     THIS AMENDMENT TO EMPLOYMENT AGREEMENT (this "Amendment"), is made and
entered into as of the 31st day of May, 2000, by and between Cidera, Inc., a
Delaware corporation (the "Company"), and  Douglas E. Humphrey (the
"Executive").

                                    RECITALS

A.  The Company and the Executive are parties to an  Employment Agreement, dated
as of June 1, 1998 (the "Employment Agreement").

B.  The Company and the Executive desire to amend the Employment Agreement as
hereinafter set forth.

                                   AGREEMENT

     In consideration of the promises and the terms and conditions set forth in
this Amendment, the parties agree as follows:

1.  Amendment to Employment Agreement.

(a)  Section 1 of the Employment Agreement is amended and restated in its
     entirety to read as set forth on Schedule A attached hereto.

(b)  Section 3 of the Employment Agreement is amended and restated in its
     entirety to read as set forth on Schedule B attached hereto.

(c)  Section 1 of Schedule A of the Employment Agreement is amended and restated
     in its entirety to read as set for on Schedule C attached hereto.

2.  Effectiveness.  This Amendment shall become effective immediately upon
execution by the Company and the Employee.  Other than the amendment set forth
herein, the Employment Agreement shall remain in full force and effect.

                            [SIGNATURE PAGE FOLLOWS]

                                      1.
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     IN WITNESS WHEREOF, the parties have executed this Amendment as of the date
first above written.


                              CIDERA, INC., a Delaware corporation


                              By:  /s/ Richard J. Hanna
                                   ------------------------------
                              Name: Richard J. Hanna

                              Title:President and CEO


                                   /s/ Douglas E. Humphrey
                                   ------------------------------
                                   Douglas E. Humphrey
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                                   SCHEDULE A

                 AMENDMENT TO SECTION 1 OF EMPLOYMENT AGREEMENT

     Section 1 of the Employment Agreement is hereby amended and restated in its
entirety to read as follows:

1.  EMPLOYMENT AND TERM.
--  -------------------

        (a)  Initial Term. The Company agrees to employ the Employee and the
Employee agrees to work for the Company, subject to the terms and conditions
below, for an additional one (1) year term, beginning June 1, 2000, and ending
May 31, 2001.

        (b)  Renewal. The term of the Employee's employment shall be extended
automatically, without further action of either party, as of June 1, 2001, and
on each succeeding anniversary of that date, for terms of one (1) year, unless
on or before ninety (90) days prior to the last day of the term of the
Employee's employment or any extension thereof, the company or the Employee
shall notify the other in writing of its intention not to renew the Employee's
employment, in which case the Employee's employment shall terminate at the end
of the original term or any extension thereof. If either party notifies the
other of its intention not to renew the Employee's employment less than ninety
(90) days prior to the end of the term of this Agreement or any extension
thereof, then such termination shall be effective ninety (90) days from such
notice. No notice of non-renewal may be given by either party after a renewal
term has commenced. Any such renewal shall be upon such terms and conditions set
forth herein, unless otherwise agreed between the Company and the Employee. The
notice of non-renewal by either party shall not constitute a breach of this
Agreement.
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                                   SCHEDULE B

                 AMENDMENT TO SECTION 3 OF EMPLOYMENT AGREEMENT

     Section 3 of the Employment Agreement is hereby amended and restated in its
entirety to read as follows:

     3.  Title; Duties.  The Employee shall serve, at the pleasure and
         -------------
discretion of the Board of Directors, as Chairman of the Board of Directors and
perform duties consistent with such title.  The Company shall not, without
Employee's express written consent, require Employee to be based anywhere other
than in Maryland, except for required travel on the Company's business to an
extent substantially consistent with travel required of persons who hold similar
positions or have similar duties with similar companies.

                                      2.
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                                   SCHEDULE C

          AMENDMENT TO SECTION 1 OF SCHEDULE A OF EMPLOYMENT AGREEMENT

     Section 1 of Schedule A of the Employment Agreement is hereby amended and
restated in its entirety to read as follows:

1.   The Employee shall be paid an initial base salary equal to $250,000 which
     shall be reviewed at least quarterly by the Board of Directors (or the
     Compensation Committee thereof) and which shall be subject to increase by
     the Board of Directors (or the Compensation Committee thereof) from time to
     time.

                                      3.