##### 



UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
 Washington, D.C. 20549
 
 FORM 10-Q
  þ
    
    QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES
EXCHANGE ACT OF 1934
 For the quarterly period ended March 31, 2008
 OR
 o
    
    TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES
EXCHANGE ACT OF 1934
 For the transition period from  to
 Commission file number 1-14279
 
 ORBITAL SCIENCES CORPORATION
  Delaware
    
    06-1209561(State of Incorporation of Registrant)
    
    (I.R.S. Employer Identification No.)
 21839 Atlantic Boulevard
Dulles, Virginia 20166
 (703) 406-5000
  þ o
  Large accelerated filer þ
    
    Accelerated filer o
    
    Non-accelerated filer o
    
    Smaller reporting company o(Do not check if a smaller reporting company)
 o þ




---



##### 



PART I
 FINANCIAL INFORMATION
 ITEM 1. FINANCIAL STATEMENTS
 ORBITAL SCIENCES CORPORATION
CONDENSED CONSOLIDATED BALANCE SHEETS
(Unaudited, in thousands, except share data)
 March 31,
    
    
    December 31,2008
    
    
    2007ASSETSCurrent assets:Cash and cash equivalents
    
    $
    244,253
    
    
    $
    235,822Receivables, net
    
    
    206,709
    
    
    
    183,507Inventories, net
    
    
    26,505
    
    
    
    26,549Deferred income taxes, net
    
    
    44,516
    
    
    
    44,420Other current assets
    
    
    3,503
    
    
    
    5,508Total current assets
    
    
    525,486
    
    
    
    495,806Investments
    
    
    25,500
    
    
    
    28,000Property, plant and equipment,net
    
    
    97,824
    
    
    
    95,713Goodwill
    
    
    55,551
    
    
    
    55,551Deferred income taxes,net
    
    
    95,723
    
    
    
    103,792Other non-current assets
    
    
    8,486
    
    
    
    9,456Total assets
    
    $
    808,570
    
    
    $
    788,318LIABILITIES AND STOCKHOLDERS EQUITYCurrent liabilities:Accounts payable and accrued expenses
    
    $
    167,286
    
    
    $
    131,805Deferred revenues
    
    
    61,289
    
    
    
    79,339Total current liabilities
    
    
    228,575
    
    
    
    211,144Long-term obligations
    
    
    143,750
    
    
    
    143,750Other non-current liabilities
    
    
    520
    
    
    
    325Total liabilities
    
    
    372,845
    
    
    
    355,219Commitments and contingenciesStockholders equity:Preferred Stock, par value $.01; 10,000,000 shares authorized, none outstanding
    
    
    
    
    
    
    Common Stock, par value $.01; 200,000,000 shares authorized, 58,426,603 and
58,753,536 shares outstanding, respectively
    
    
    584
    
    
    
    587Additional paid-in capital
    
    
    546,508
    
    
    
    554,451Accumulated other comprehensive loss
    
    
    (9,861
    )
    
    
    (6,751
    )Accumulated deficit
    
    
    (101,506
    )
    
    
    (115,188
    )Total stockholders equity
    
    
    435,725
    
    
    
    433,099Total liabilities and stockholders equity
    
    $
    808,570
    
    
    $
    788,318
 See accompanying notes to condensed consolidated financial statements
 1




---



##### 



ORBITAL SCIENCES CORPORATION
CONDENSED CONSOLIDATED INCOME STATEMENTS
(Unaudited, in thousands, except per share data)
 Quarters Ended March 31,2008
    
    
    2007Revenues
    
    $
    295,964
    
    
    $
    228,222Costs of revenues
    
    
    243,542
    
    
    
    188,256Research and development expenses
    
    
    8,982
    
    
    
    2,850Selling, general and administrative expenses
    
    
    21,885
    
    
    
    19,595Income from operations
    
    
    21,555
    
    
    
    17,521Interest income and other
    
    
    2,386
    
    
    
    3,038Interest expense
    
    
    (1,045
    )
    
    
    (1,148
    )Income before income taxes
    
    
    22,896
    
    
    
    19,411Provision for income taxes
    
    
    (9,214
    )
    
    
    (7,959
    )Net income
    
    $
    13,682
    
    
    $
    11,452Basic net income per share
    
    $
    0.23
    
    
    $
    0.19Diluted net income per share
    
    $
    0.23
    
    
    $
    0.19
 See accompanying notes to condensed consolidated financial statements
 2




---



##### 



ORBITAL SCIENCES CORPORATION
CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS
(Unaudited, in thousands)
 Quarters Ended March 31,2008
    
    
    2007Cash Flows From Operating Activities:Net income
    
    $
    13,682
    
    
    $
    11,452Adjustments to reconcile net income to net cash provided by operating activities:Depreciation expense
    
    
    4,535
    
    
    
    4,108Deferred taxes
    
    
    7,783
    
    
    
    6,854Stock-based compensation and other
    
    
    2,166
    
    
    
    2,023Changes in assets and liabilities
    
    
    (3,617
    )
    
    
    (16,875
    )Net cash provided by operating activities
    
    
    24,549
    
    
    
    7,562Cash Flows From Investing Activities:Capital expenditures
    
    
    (6,736
    )
    
    
    (3,707
    )Purchases of investments
    
    
    
    
    
    
    (65,000
    )Sales of investments
    
    
    
    
    
    
    65,000Change in cash restricted for letters of credit, net
    
    
    
    
    
    
    (1,000
    )Net cash used in investing activities
    
    
    (6,736
    )
    
    
    (4,707
    )Cash Flows From Financing Activities:Repurchase of common stock
    
    
    (11,781
    )
    
    
    Net proceeds from issuances of common stock
    
    
    1,656
    
    
    
    3,748Tax benefit of share-based compensation and other
    
    
    743
    
    
    
    759Net cash (used in) provided by financing activities
    
    
    (9,382
    )
    
    
    4,507Net increase in cash and cash equivalents
    
    
    8,431
    
    
    
    7,362Cash and cash equivalents, beginning of period
    
    
    235,822
    
    
    
    199,751Cash and cash equivalents, end of period
    
    $
    244,253
    
    
    $
    207,113
 See accompanying notes to condensed consolidated financial statements.
 3




---



##### 



ORBITAL SCIENCES CORPORATION
NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS
March 31, 2008 and 2007
(Unaudited)
 (1) Basis of Presentation
    (2) Preparation of Condensed Consolidated Financial Statements
   4




---



##### 



(3) Adoption of SFAS No. 157 and SFAS No. 159
 Fair Value Measurements
 The Fair Value Option for Financial
Assets and Financial Liabilities  Including an Amendment of FASB Statement No. 115.
 5




---



##### 



(4) Industry Segment Information
  
    
    Launch Vehicles.Rockets that are used as interceptor and target vehicles for missile
defense systems, small-class space launch vehicles that place satellites into Earth orbit,
and suborbital launch vehicles that place payloads into a variety of high-altitude
trajectories.
    
    Satellites and Space Systems.Small- and medium-class spacecraft that are used to
enable global and regional communications and broadcasting, to conduct space-related
scientific research, to carry out interplanetary and other deep-space exploration missions,
to demonstrate new space technologies, to collect imagery and other remotely-sensed data
about the Earth and to enable national security applications.
    
    Advanced Space Programs.Human-rated space systems for Earth-orbit and lunar
exploration, advanced launch systems for medium-class satellites, and small satellites and
satellite subsystems primarily used for national security space programs and to demonstrate
new space technologies.
    
    Transportation Management Systems.Software-based transportation management systems for
public transit agencies and private vehicle fleet operators (see Note 16 regarding the
companys agreement to sell its transportation management systems business unit).
  6




---



##### 



(in thousands)
 Quarters Ended March 31,2008
    
    2007Launch Vehicles:Revenues
    
    $
    105,257
    
    
    $
    88,251Operating income
    
    
    7,615
    
    
    
    7,863Identifiable assets
    
    
    122,350
    
    
    
    115,646
    (3)Capital expenditures
    
    
    4,002
    
    
    
    681Depreciation
    
    
    1,287
    
    
    
    1,346Satellites and Space Systems(1):Revenues(2)
    
    $
    106,402
    
    
    $
    104,213Operating income
    
    
    7,869
    
    
    
    6,865Identifiable assets
    
    
    166,752
    
    
    
    176,538
    (3)Capital expenditures
    
    
    1,856
    
    
    
    1,572Depreciation
    
    
    2,141
    
    
    
    1,805Advanced Space Programs(1):Revenues
    
    $
    72,609
    
    
    $
    26,344Operating income
    
    
    4,841
    
    
    
    2,113Identifiable assets
    
    
    48,580
    
    
    
    23,767
    (3)Capital expenditures
    
    
    
    
    
    
    Depreciation
    
    
    3
    
    
    
    51Transportation Management Systems:Revenues
    
    $
    12,419
    
    
    $
    10,275Operating income
    
    
    1,230
    
    
    
    680Identifiable assets
    
    
    23,214
    
    
    
    20,451
    (3)Capital expenditures
    
    
    199
    
    
    
    28Depreciation
    
    
    170
    
    
    
    154Corporate and Other:Revenues(2)
    
    $
    (723
    )
    
    $
    (861
    )Operating income
    
    
    
    
    
    
    Identifiable assets
    
    
    447,674
    
    
    
    451,916
    (3)Capital expenditures
    
    
    679
    
    
    
    1,426Depreciation
    
    
    934
    
    
    
    752Consolidated:Revenues
    
    $
    295,964
    
    
    $
    228,222Operating income
    
    
    21,555
    
    
    
    17,521Identifiable assets
    
    
    808,570
    
    
    
    788,318
    (3)Capital expenditures
    
    
    6,736
    
    
    
    3,707Depreciation
    
    
    4,535
    
    
    
    4,108
 
 (1)
    
    Effective December 31, 2007, the company disaggregated Advanced Space Programs
from Satellites and Space Systems. The first quarter 2007 presentation has been
reclassified to conform to the 2008 presentation.(2)
    
    Corporate and other revenues are comprised solely of the elimination of
intersegment sales. Satellites and Space Systems revenues include $0.5 million and $0.6
million of intersegment sales in the quarters ended March 31, 2008 and 2007, respectively.(3)
    
    As of December 31, 2007. 7




---



##### 



(5) Earnings Per Share
 (in thousands)
 Quarters Ended March 31,2008
    
    2007Weighted average of outstanding shares for basic EPS
    
    
    58,495
    
    
    
    59,092Dilutive effect of stock options and units
    
    
    1,692
    
    
    
    1,853Shares for diluted EPS
    
    
    60,187
    
    
    
    60,945
  (6) Receivables
 (in thousands)
 March 31, 2008
    
    
    December 31, 2007Billed
    
    $
    73,782
    
    
    $
    36,721Unbilled
    
    
    133,042
    
    
    
    146,901Allowance for doubtful accounts
    
    
    (115
    )
    
    
    (115
    )Total
    
    $
    206,709
    
    
    $
    183,507
    8




---



##### 



(7) Inventories
 (in thousands)
 March 31, 2008
    
    
    December 31, 2007Inventories
    
    $
    27,615
    
    
    $
    27,659Allowance for inventory obsolescence
    
    
    (1,110
    )
    
    
    (1,110
    )Total
    
    $
    26,505
    
    
    $
    26,549
  (8) Investments
    9




---



##### 



(in thousands)
 Quarter EndedMarch 31, 2008Fair value(1) at beginning of period
    
    $
    28,000Total unrealized losses (none included in earnings)
    
    
    (2,500
    )Fair value(1) at end of period
    
    $
    25,500
 
 (1)
    
    As discussed above, the company estimated the fair value of its auction-rate
securities based upon discounted cash flow analyses using the best
available information. Under SFAS No. 157, such valuation assumptions are defined as level 3 inputs. (9) Debt
 Convertible Notes
     10




---



##### 



Credit Facility
  Debt Covenants
  (10) Comprehensive Income
   11




---



##### 



(11) Stock-Based Compensation
 (dollars in millions, except per-option and per-unit average values)
 Restricted Stock Units
    
    Stock OptionsWeightedAverageMeasurementNumber of
    
    Date
    
    Number of
    
    Weighted AverageUnits
    
    Fair Value
    
    Options
    
    Exercise PriceOutstanding at December 31, 2007
    
    
    1,097,188
    
    
    $
    18.81
    
    
    
    3,535,512
    
    
    $
    11.77Granted(1)
    
    
    18,595
    
    
    
    24.31
    
    
    
    
    
    
    
    Exercised
    
    
    
    
    
    
    
    
    
    
    (134,584
    )
    
    
    10.37Vested
    
    
    (34,197
    )
    
    
    17.93
    
    
    
    
    
    
    
    Forfeited
    
    
    (3,833
    )
    
    
    18.71
    
    
    
    (3,200
    )
    
    
    5.22Expired
    
    
    
    
    
    
    
    
    
    
    (120,020
    )
    
    
    45.54Outstanding at March 31, 2008
    
    
    1,077,753
    
    
    $
    18.93
    
    
    
    3,277,708
    (2)
    
    $
    10.59
 
 (1)
    
    The fair value of restricted stock unit grants is determined based on the closing market
price of Orbitals common stock on the date of grant. Such value is recognized as expense
over the service period, net of estimated forfeitures.(2)
    
    The weighted average remaining contractual term is 3.75 years. Quarter Ended
    
    Quarter EndedMarch 31, 2008
    
    March 31, 2007Stock-based compensation expense
    
    $
    2.1
    
    
    $
    1.9Income tax benefit related to stock-based compensation expense
    
    
    0.7
    
    
    
    0.6Intrinsic value of options exercised computed as the market
price on the exercise date less the price paid to exercise the
options
    
    
    1.8
    
    
    
    3.4Cash received from exercise of options
    
    
    1.4
    
    
    
    3.3Tax benefits recorded as credits to additional paid-in capital related
to stock-based compensation transactions
    
    
    0.7
    
    
    
    0.8
 As ofMarch 31, 2008Shares of common stock available for grant under the companys stock-based incentive plans
    
    
    1,510,461Aggregate intrinsic value of restricted stock units that are expected to vest
    
    
    $26.0Unrecognized compensation cost related to non-vested restricted stock units expected to be
recognized over a weighted-average period of 1.57 years
    
    
    13.3Aggregate intrinsic value of stock options outstanding, all fully vested
    
    
    46.0
 (12) Research and Development
   12




---



##### 



(13) Income Taxes
  (14) Commitments and Contingencies
 U.S. Government Contracts
   Litigation
 qui tam United States of America ex rel.W. Austin Sallade v. Orbital
Sciences Corporation
  13




---



##### 



(15) Recent Accounting Pronouncements
 Business Combinations.
 14




---



##### 



Noncontrolling Interests in Consolidated
Financial Statements  An Amendment of ARB No. 51.
 (16) Subsequent Event
  15




---



##### 



ITEM 2. MANAGEMENTS DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS
   
    
    Launch Vehicles.Rockets that are used as interceptor and target vehicles for missile
defense systems, small-class space launch vehicles that place satellites into Earth orbit,
and suborbital launch vehicles that place payloads into a variety of high-altitude
trajectories.
    
    Satellites and Space Systems.Small- and medium-class spacecraft that are used to
enable global and regional communications and broadcasting, to conduct space-related
scientific research, to carry out interplanetary and other deep-space exploration missions,
to demonstrate new space technologies, to collect imagery and other remotely-sensed data
about the Earth and to enable national security applications.
    
    Advanced Space Programs.Human-rated space systems for Earth-orbit and lunar
exploration, advanced launch systems for medium-class satellites, and small satellites and
satellite subsystems primarily used for national security space programs and to demonstrate
new space technologies.
    
    Transportation Management Systems.Software-based transportation management systems for
public transit agencies and private vehicle fleet operators.
  16




---



##### 



Consolidated Results of Operations for the Quarters Ended March 31, 2008 and 2007
 Revenues
 Cost of Revenues
 Research and Development Expenses
 Selling, General and Administrative Expenses
 Interest Income and Other
 17




---



##### 



Interest Expense
 Income Taxes
 Net Income
 Segment Results for the Quarters Ended March 31, 2008 and 2007
  (in thousands)
 Quarters Ended March 31,2008
    
    
    2007Revenues:Launch Vehicles
    
    $
    105,257
    
    
    $
    88,251Satellites and Space Systems(1)
    
    
    106,402
    
    
    
    104,213Advanced Space Programs(1)
    
    
    72,609
    
    
    
    26,344Transportation Management Systems
    
    
    12,419
    
    
    
    10,275Corporate and Other
    
    
    (723
    )
    
    
    (861
    )Total
    
    $
    295,964
    
    
    $
    228,222Income from Operations:Launch Vehicles
    
    $
    7,615
    
    
    $
    7,863Satellites and Space Systems(1)
    
    
    7,869
    
    
    
    6,865Advanced Space Programs(1)
    
    
    4,841
    
    
    
    2,113Transportation Management Systems
    
    
    1,230
    
    
    
    680Total
    
    $
    21,555
    
    
    $
    17,521
 
 (1)
    
    Effective December 31, 2007, the company disaggregated Advanced Space Programs
from Satellites and Space Systems. The first quarter 2007 presentation has been
reclassified to conform to the 2008 presentation. 18




---



##### 



Launch Vehicles
    19




---



##### 



Satellites and Space Systems
   Advanced Space Programs
  20




---



##### 



Transportation Management Systems
  Corporate and Other
 Backlog
   Liquidity and Capital Resources
 Cash Flow from Operating Activities
  Cash Flow from Investing Activities
  21




---



##### 



Cash Flow from Financing Activities
  Convertible Notes
   Credit
Facility -
 Debt
Covenants -
 22




---



##### 



Available Cash and Future Funding
    Off-Balance Sheet Arrangements
  Recent Accounting Pronouncements
 Business Combinations.
 23




---



##### 



Noncontrolling Interests in Consolidated
Financial Statements  An Amendment of ARB No. 51.
 24




---



##### 



ITEM 3. QUANTITATIVE AND QUALITATIVE DISCLOSURES ABOUT MARKET RISK
  Uncertainties in the Credit Markets
    Foreign Currency Exchange Rate Risk
  25




---



##### 



Interest Rate Risk
    Deferred Compensation Plan
  26




---



##### 



ITEM 4. CONTROLS AND PROCEDURES
 Evaluation of Disclosure Controls and Procedures
  Changes in Internal Controls
  27




---



##### 



PART II
 OTHER INFORMATION
 ITEM 1. LEGAL PROCEEDINGS
 In 2007, we were advised by the Civil Division of the Department of Justice (DoJ)
that we had been named as a defendant in a lawsuit brought by a former employee and
filed under seal on February 23, 2005, in the United States District Court for the
District of Arizona, under the qui tamprovisions of the civil False Claims Act,
which permit an individual to bring suit in the name of the United States and share
in any recovery. The Court subsequently unsealed the matter, which is captioned
United States of America ex rel.W. Austin Sallade v. Orbital Sciences
Corporation.The complaint alleges that our Launch Systems Group submitted false and fraudulent
claims for payment to the U.S. government allegedly by misclassifying and
mischarging costs and by engaging in defective pricing. The complaint asserts that
as a result of the allegedly wrongful conduct, the United States suffered damages
and that we are liable to the United States for three times the amount of the
alleged damages, plus civil penalties of up to $10,000 for each false claim and
punitive damages. We have devoted significant time and resources to investigate the
issues raised by the complaint and, while we cannot predict the outcome of any
litigation, we believe we have strong substantive defenses to all of the claims. We
are vigorously defending this lawsuit.The above-described lawsuit relates to matters underlying an investigation by the
DoJ that we learned of in 2005 involving suspected civil and criminal violations of
government contracting laws and regulations in connection with certain U.S.
government launch vehicle programs. While the Civil Division of the DoJ has
declined to intervene in such lawsuit, in the future it could seek to intervene with
permission from the Court. To our knowledge, the criminal investigation remains
open. We have cooperated fully with the U.S. government authorities in connection
with their investigation. We cannot predict whether the government ultimately will
conclude that there have been any violations by us of any federal contracting laws,
policies or procedures, or any other applicable laws, or whether the former employee
plaintiff will prevail in the lawsuit. The outcome of the government investigation
could subject us to criminal, civil and/or administrative penalties and up to treble
damages depending on the nature of such violations, which could have a material
adverse effect on our results of operations or financial condition.
 28




---



##### 



In addition, from time to time we are party to certain litigation or other legal
proceedings arising in the ordinary course of business. Because of the
uncertainties inherent in litigation, we cannot predict whether the outcome of such
litigation or other legal proceedings will have a material adverse effect on our
results of operations or financial condition.
 ITEM 1A. RISK FACTORS
 There are no material changes to the risk factors disclosed in the companys Annual
Report on Form 10-K for the fiscal year ended December 31, 2007.
 ITEM 2. UNREGISTERED SALES OF EQUITY SECURITIES AND USE OF PROCEEDS
     Total Number of
    
    
    Maximum NumberShares
    
    
    (or ApproximatePurchased as
    
    
    Dollar Value) ofTotal
    
    
    
    
    
    
    Part of Publicly
    
    
    Shares That MayNumber of
    
    
    Average Price
    
    
    Announced
    
    
    Yet Be PurchasedShares
    
    
    Paid Per
    
    
    Plans or
    
    
    Under the Plans orPeriod
    
    Purchased
    
    
    Share
    
    

Programs 1
    
    

Programs 1January 1, 2008 to
January 31, 2008
    
    
    277,500
    
    
    $
    23.67
    
    
    
    277,500
    
    
    $
    10,020,735February 1, 2008 to
February 29, 2008
    
    
    106,344
    
    
    $
    23.70
    
    
    
    106,344
    
    
    $
    7,499,993March 1, 2008 to
March 31, 2008
    
    
    118,600
    
    
    $
    22.70
    
    
    
    118,600
    
    
    $
    4,807,210TOTAL
    
    
    502,444
    
    
    $
    23.45
    
    
    
    502,444
    
    
    $
    4,807,210
 
 (1)
    
    On May 2, 2007, we announced the companys plan, subject to
certain conditions, to repurchase up to an aggregate of $50 million of
outstanding common stock. This plan expires on May 2, 2008. All purchases
made during the quarter ended March 31, 2008 were made under this plan in open
market transactions. On April 24, 2008, our Board of Directors authorized a
new plan for the purchase of up to $50 million of outstanding common stock over
a 12-month period commencing April 25, 2008. 29




---



##### 



ITEM 3. DEFAULTS UPON SENIOR SECURITIES
  ITEM 4. SUBMISSION OF MATTERS TO A VOTE OF SECURITY HOLDERS
  ITEM 5. OTHER INFORMATION
  ITEM 6. EXHIBITS
 (a)
    
    Exhibits  A complete listing of exhibits required is given in
the Exhibit Index.
 30




---



##### 



SIGNATURES
  ORBITAL SCIENCES CORPORATIONDATED: April 25, 2008
    
    By:
    
    /s/ David W. ThompsonDavid W. ThompsonChairman and Chief Executive OfficerDATED: April 25, 2008
    
    By:
    
    /s/ Garrett E. PierceGarrett E. PierceVice Chairman and Chief Financial Officer
 31




---



##### 



EXHIBIT INDEX
  Exhibit No.
    
    Description3.1
    
    Restated Certificate of Incorporation (incorporated by reference to Exhibit
4.1 to the companys Registration Statement on Form S-3 (File Number
333-08769) filed and effective on July 25, 1996).3.2
    
    Amended and Restated Bylaws (incorporated by reference to Exhibit 3.2 to the
companys Quarterly Report on Form 10-Q for the quarter ended June 30, 2005).3.3
    
    Certificate of Amendment to Restated Certificate of Incorporation, dated
April 29, 1997 (incorporated by reference to Exhibit 3.3 to the companys
Annual Report on Form 10-K for the fiscal year ended December 31, 1998).3.4
    
    Certificate of Amendment to Restated Certificate of Incorporation, dated
April 30, 2003 (incorporated by reference to Exhibit 3.4 to the companys
Quarterly Report on Form 10-Q for the quarter ended June 30, 2003).3.5
    
    Certificate of Designation, Preferences and Rights of Series B Junior
Participating Preferred Stock, dated November 2, 1998 (incorporated by
reference to Exhibit 2 to the companys Registration Statement on Form 8-A
filed on November 2, 1998).4.1
    
    Form of Certificate of Common Stock (incorporated by
reference to Exhibit 4.1 to the companys Registration
Statement on Form S-1 (File Number 33-33453) filed on
February 9, 1990 and effective on April 24, 1990).4.2
    
    Indenture dated as of December 13, 2006, by and between
Orbital Sciences Corporation and The Bank of New York, as
Trustee (incorporated by reference to Exhibit 4.1 to the
companys Current Report on Form 8-K filed on December 13,
2006).4.3
    
    Form of 2.4375% Convertible Senior Subordinated Note due 2027
(incorporated by reference to Exhibit 4.2 to the companys
Current Report on Form 8-K filed on December 13, 2006).4.4
    
    Registration Rights Agreement dated as of December 13, 2006,
by and among Orbital Sciences Corporation, Wachovia Capital
Markets, LLC and Banc of America Securities LLC (incorporated
by reference to Exhibit 4.3 to the companys Current Report
on Form 8-K filed on December 13, 2006).
 32




---



##### 



Exhibit No.
    
    Description4.5
    
    Rights Agreement dated as of October 22, 1998, by and between
Orbital Sciences Corporation and BankBoston N.A., as Rights
Agent (incorporated by reference to Exhibit 1 to the
companys Report on Form 8-A filed on November 2, 1998).4.6
    
    Form of Rights Certificate (incorporated by reference to
Exhibit 3 to the companys Report on Form 8-A filed on
November 2, 1998).31.1
    
    Certification of Chairman and Chief Executive Officer
pursuant to Section 302 of the Sarbanes-Oxley Act of 2002 (18
U.S.C. Section 1350) (transmitted herewith).31.2
    
    Certification of Vice Chairman and Chief Financial Officer
pursuant to Section 302 of the Sarbanes-Oxley Act of 2002 (18
U.S.C. Section 1350) (transmitted herewith).32.1
    
    Written Statement of Chairman and Chief Executive Officer
pursuant to Section 906 of the Sarbanes-Oxley Act of 2002 (18
U.S.C. Section 1350) (transmitted herewith).32.2
    
    Written Statement of Vice Chairman and Chief Financial Officer
pursuant to Section 906 of the Sarbanes-Oxley Act of 2002 (18
U.S.C. Section 1350) (transmitted herewith).
 33