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The United States Naval Observatory
  • Organization
  • IAU Double Star Center
  • IERS ICRS Center
  • IVS (VLBI) Analysis Center
  • IVS (VLBI) Analysis Center for Source Structure
  • Data Products
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Celestial Reference Frame Department
  •   Organization
    • Overview
    • History
    • Institutional Relationships
    • F.A.Q.
    • Publications
    • Contact
  •   IAU Double Star Center
    • WDS Description
      • Full Page
      • Introduction And Growth Of The WDS
      • New BDS <---> ADS <---> WDS Cross-Reference
      • Unpublished Measures
      • Hipparcos, Tycho-2, & The TDSC
      • Duplicate Discovery Designations, Arcsecond Coordinates And Other Topics
      • Available Files And Links
      • Requests And Acknowledgments
      • Frequently Asked Questions
    • WDS Catalog
      • WDS Catalog: Full
      • WDS Catalog: 00-05 Hour Section
      • WDS Catalog: 06-11 Hour Section
      • WDS Catalog: 12-17 Hour Section
      • WDS Catalog: 18-23 Hour Section
      • WDS Catalog With Precise Last Only
      • WDS Catalog As An SQL Database (Original Code, Danley Hsu; Improved Code, Damien Mattei)
      • WDS With Constellation And Bayer/Flamsteed Designation (When Applicable) Appended
      • Format Of The Current WDS
      • Notes File For The WDS
      • References And Discoverer Codes
    • WDS Supplemental Catalog
      • WDS Supplemental Catalog: Explanatory file
      • WDS Supplemental Catalog: Summary
      • WDS Supplemental Catalog: 00-05 Hour Section (All Data)
      • WDS Supplemental Catalog: 06-11 Hour Section (All Data)
      • WDS Supplemental Catalog: 12-17 Hour Section (All Data)
      • WDS Supplemental Catalog: 18-23 Hour Section (All Data)
      • WDS Supplemental Catalog: Format Of Files
    • IAU Commission G1
    • Sixth Catalog Of Orbits Of Visual Binary Stars
      • Full Page
      • Introduction
      • Orbit Grading Method
      • Description Of The Catalog
      • Catalog statistics
      • Acknowledgments And References
      • Orbital Elements: Html
      • Orbital Elements: Text
      • Orbital Elements: SQL
      • Ephemerides:Html
      • Ephemerides:Text
      • Notes:Html
      • Notes:Text
      • References:Html
      • References:Text
      • Orbital Elements: Frame Version
      • Formats Of Elements And Ephemerides Files
      • Calibration Candidates
      • Top 25 Orbit Calculators
      • Master File Database
    • Catalog Of Rectilinear Elements
      • Description Page
      • Main Catalog
      • Notes To Individual Systems
      • Ephemerides For 2015-2040
      • References To Comments
      • Notes To Individual Systems
    • Fourth Catalog Of Interferometric Measurements Of Binary Stars
      • Description Page
      • Whole Catalog: Plain Text
      • Whole Catalog: GZip
      • 00 Hrs
      • 01 Hrs
      • 02 Hrs
      • 03 Hrs
      • 04 Hrs
      • 05 Hrs
      • 06 Hrs
      • 07 Hrs
      • 08 Hrs
      • 09 Hrs
      • 10 Hrs
      • 11 Hrs
      • 12 Hrs
      • 13 Hrs
      • 14 Hrs
      • 15 Hrs
      • 16 Hrs
      • 17 Hrs
      • 18 Hrs
      • 19 Hrs
      • 20 Hrs
      • 21 Hrs
      • 22 Hrs
      • 23 Hrs
      • Notes
      • Reference
    • The Delta-M Catalog
      • Description Page
      • Method Key To The Above File
      • Number And Mean Delta-m For Various Methods
      • Reference File
      • The Delta-M Catalog
  •   IERS ICRS Center
    • Overview
    • Conceptual Background
    • FRIDA
      • Overview
      • FRIDA Database
    • FRAMEx
      • Overview
      • Conceptual background
      • Publications (FRAMEx-specific)
  •   IVS (VLBI) Analysis Center
    • Overview
    • Background
    • UT1-UTC
      • Overview
      • Analysis Reports
      • Analyzed Databases
    • 24 Hour Sessions
      • Overview
      • Analysis Reports
      • Analyzed Databases
    • Global solutions
      • Overview
      • Background
      • Celestial Reference Frame
      • Terrestrial Reference Frame
      • Earth Orientation Parameters
      • Quarterly VLBI Solution
      • Solution Comparisons
      • SINEX Files
  •   IVS (VLBI) Analysis Center for Source Structure
    • Overview
    • Background
    • FRIDA
      • Overview
      • FRIDA Database
  •   Data Products
    • Overview
    • IAU Double star center
      • Overview
      • WDS Catalog
        • WDS Catalog: Full
        • WDS Catalog: 00-05 Hour Section
        • WDS Catalog: 06-11 Hour Section
        • WDS Catalog: 12-17 Hour Section
        • WDS Catalog: 18-23 Hour Section
        • WDS Catalog With Precise Last Only
        • WDS Catalog As An SQL Database (Original Code, Danley Hsu; Improved Code, Damien Mattei)
        • WDS With Constellation And Bayer/Flamsteed Designation (When Applicable) Appended
        • Format Of The Current WDS
        • Notes File For The WDS
        • References And Discoverer Codes
      • WDS Supplemental Catalog
        • WDS Supplemental Catalog: Explanatory file
        • WDS Supplemental Catalog: Summary
        • WDS Supplemental Catalog: 00-05 Hour Section (All Data)
        • WDS Supplemental Catalog: 06-11 Hour Section (All Data)
        • WDS Supplemental Catalog: 12-17 Hour Section (All Data)
        • WDS Supplemental Catalog: 18-23 Hour Section (All Data)
        • WDS Supplemental Catalog: Format Of Files
      • Sixth Catalog Of Orbits Of Visual Binary Stars
        • Full Page
        • Introduction
        • Orbit Grading Method
        • Description Of The Catalog
        • Catalog statistics
        • Acknowledgments And References
        • Orbital Elements: Html
        • Orbital Elements: Text
        • Orbital Elements: SQL
        • Ephemerides:Html
        • Ephemerides:Text
        • Notes:Html
        • Notes:Text
        • References:Html
        • References:Text
        • Orbital Elements: Frame Version
        • Formats Of Elements And Ephemerides Files
        • Calibration Candidates
        • Top 25 Orbit Calculators
        • Master File Database
      • Catalog Of Rectilinear Elements
        • Description Page
        • Main Catalog
        • Notes To Individual Systems
        • Ephemerides For 2015-2040
        • References To Comments
        • Notes To Individual Systems
      • Fourth Catalog Of Interferometric Measurements Of Binary Stars
        • Description Page
        • Whole Catalog: Plain Text
        • Whole Catalog: GZip
        • 00 Hrs
        • 01 Hrs
        • 02 Hrs
        • 03 Hrs
        • 04 Hrs
        • 05 Hrs
        • 06 Hrs
        • 07 Hrs
        • 08 Hrs
        • 09 Hrs
        • 10 Hrs
        • 11 Hrs
        • 12 Hrs
        • 13 Hrs
        • 14 Hrs
        • 15 Hrs
        • 16 Hrs*
        • 17 Hrs
        • 18 Hrs
        • 19 Hrs
        • 20 Hrs
        • 21 Hrs
        • 22 Hrs
        • 23 Hrs
        • Notes
        • Reference
      • The Delta-M Catalog
        • Description Page
        • Method Key To The Above File
        • Number And Mean Delta-m For Various Methods
        • Reference File
        • The Delta-M Catalog
    • FRIDA
      • Overview
      • FRIDA Database
    • 24 Hour Sessions
      • Overview
      • Analysis Reports
      • Analyzed Databases
    • UT1-UTC
      • Overview
      • Analysis Reports
      • Analyzed Databases
    • Global Solutions
      • Overview
      • Background
      • Celestial Reference Frame
      • Terrestrial Reference Frame
      • Earth Orientation Parameters
      • Quarterly VLBI Solution
      • Solution Comparisons
      • SINEX Files
Celestial Reference Frame Department, USNO
3450 Massachusetts Ave NW,
Washington, DC 20392
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