USNA-5: Laser Relativity Satellite (WeberSat*-LARES)

1. USNA-5: Laser Relativity Satellite (WeberSat*-LARES) Lt Col Billy R. Smith, Jr., USAF USNA Small Satellite Program (410) 293-6410 brsmith@usna.edu *In Honor of Dr Joseph Weber, USNA Class of ‘40

2. USNA Small Satellite Program • Mission Statement: • Pursue flight opportunities for miniature satellites designed, constructed, tested, and commanded or controlled by Midshipmen. • Functions: • Provide funds for component purchase, construction and testing; and, travel in support of testing and integration • Coordinate with DoD/NASA laboratories or with universities for collaborative projects • Guide the Midshipmen through the DoD Space Experiments Review Board flight selection process

3. Current Missions • Founded Fall Semester 1998 • USNA-0: Stanford AudioPhonic PHotographic InfraREd Satellite (Sapphire) • USNA-1: Prototype Communications Satellite (PCSat) • Both launched 30 September 2001 from Kodiak Launch Complex, Alaska

4. PCSat Concept of Operations PCSat Summer Cruise Ground Station Mobile HAMs Command and Control World Wide Web User USNA

5. Timetable

6. The Challenge Recent developments in cosmology elevate the importance of dynamical investigations of General Relativity: “string theory” explanations of “dark energy” may violate General Relativity • Data needed to evaluate GR and proposed alternative theories • Improved bounds on very weak, long range gravitational forces, and tests of the equivalence principle • High precision measurement of Lense-Thirring inertial frame dragging (gravito-magnetic effect) • Improved upper bounds on spatial anistropies of the gravitational interaction • Definition of improved dynamical inertial frame; comparison with frame established by distant quasars

7. Concept Objective: Educate 1/C Mids in Astronautics curriculum in Program Management, flight certification and spacecraft testing. • Ref: USSpaceCom Long Range Plan, p. 73, 77-79. • Report of the Commission to Assess United States National Security, Space Management and Organization, Chapter VIII “Conclusions”, p. 100 Establish inertial reference frame free of Newtonian gravitational perturbations. Description: WeberSat completes three-body system interrogated by laser ranging. Intersection of orbital planes establishes stable inertial reference . Equipment: • Inert sphere covered with corner reflectors • International Laser Ranging Service (ILRS) Network

8. The Spacecraft AluminumHalf-spheres Brass Core 1.9 cm Brass Stud

9. Ground Support

10. The Launch Vehicle Peacekeeper Space Launch Vehicle (SLV) Capabilities: Orbit: 100 - 1000 NMi Payload Weight: 700 to 3500 lbm Inclination: 28.5 – 99 deg Launch Locations: CCAFS VAFB Wallops Kodiak Current Launch Systems: System Customers PKSLV TBD Ref: Det12 SMC/RSLP USU Small Satellite Conference Brief, 12 Aug 2003

11. PK SLV “Preliminary Performance Estimate” Ref: Det12 SMC/RSLP USU Small Satellite Conference Brief, 12 Aug 2003

12. Peacekeeper Cost • First Launch* - Cost Plus Incentive Fee (CPIF) + Mission Success Payment • Fly away cost estimated from $26M to $29M** • Subsequent Launches - Fixed Price Incentive Firm (FPIF) + Mission Success Payment • Fly away cost $17.5M to $19.5M** Ref: Det12 SMC/RSLP USU Small Satellite Conference Brief, 12 Aug 2003 * First PK Customer -- CPIF Cost Structure, Subsequent Customers -- FPIF ** Prices are for First Year of Contract. Price Range Covers Most Available Enhancements

13. Justification • Military Relevance • Adds Program Management Experience to the Aerospace Engineering Major • Ref: USSpaceCom Long Range Plan, p. 73, 77-79. • Improves knowledge of global plate tectonics, crustal deformation and determination of variability of Earth’s rotation • Ballistic missile accuracy • Improves knowledge of non-gravitational perturbations on high-altitude spacecraft • Aerodynamic drag • Thermal thrust • Need for Space flight • Third satellite in complementary inclination orbit required to establish inertial reference plane. • Comparison to Alternatives • No new technology or instrumentation required; passive, low-risk satellite • Marked improvement over current constellation in calibrated standard deviations of parameters for • Earth Geocenter • Tracking Station XYZ • Earth Orientation • Geopotential model • Earth tides

14. Solar glint observations to be taken by Goddard; analyzed for rotational dynamics of satellite by U of MD, U of Rome and U of Lecce. Laser ranging observations and analysis to be accomplished by Goddard. Thermal thrust evaluation from glint data to be done by Goddard, followed by modeling of perturbations and fine corrections to orbital representations. Relativistic analysis to be conducted by U of Lecce, U of Rome, U of MD, U of TX – Austin, Los Alamos National Lab and Goddard. Student design teams will graduate and become part of Navy’s future space cadre. Applicable category of this research is Basic Research. Summary of Data Application

15. Benefits • Precision measurement of Lense-Thirring effect • Confirmation of results from Gravity Probe B • Improved bounds on • Weak, long-range new gravitational forces • Violations of the Equivalence Principle • More accurate measurements of Parameterized-Post-Newtonian parameters via relativistic precession of perigee • Contributions to Geodesy and Geodynamics • Plate tectonics • Crustal deformation • Earth angular velocity variations • Earth barycenter location • Aerodynamic drag and thermal thrust effects in Mid-Earth Orbit

16. Organization INFN USNA SSP STP U of MD Goddard U of TX - Aus U of Rome U of Lecce Delft Inst of Tech

17. Test and Integration INFN USNA SSP STP Mid Design Team Separation System Vibration Test Thermal/Vac Test