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Professional Development Short Course On:

                          Space Systems Fundamentals


                                          Instructor:
                                    Dr. Mike Gruntman




                                    http://www.ATIcourses.com/schedule.htm
ATI Course Schedule:
                                    http://www.aticourses.com/space_systems_fundamentals.htm
ATI's Space Systems Fundamentals:




 349 Berkshire Drive • Riva, Maryland 21140
 888-501-2100 • 410-956-8805
 Website: www.ATIcourses.com • Email: ATI@ATIcourses.com
Space Systems Fundamentals

                             NEW!                                          May 18-21, 2009
                                                                       Albuquerque, New Mexico
                                                                          June 22-25, 2009
                                                                           Beltsville, Maryland
                                                                       $1590        (9:00am - 4:30pm)
                                                                 quot;Register 3 or More & Receive $10000 each
                      Summary                                             Off The Course Tuition.quot;
    This four-day course provides an overview of the
 fundamentals of concepts and technologies of modern
 spacecraft systems design. Satellite system and
 mission design is an essentially interdisciplinary sport
                                                                             Course Outline
 that combines engineering, science, and external
 phenomena. We will concentrate on scientific and               1. Space Missions And Applications. Science,
 engineering foundations of spacecraft systems and           exploration, commercial, national security. Customers.
 interactions among various subsystems. Examples                2. Space Environment And Spacecraft
 show how to quantitatively estimate various mission         Interaction. Universe, galaxy, solar system.
 elements (such as velocity increments) and conditions       Coordinate systems. Time. Solar cycle. Plasma.
 (equilibrium temperature) and how to size major             Geomagnetic field. Atmosphere, ionosphere,
 spacecraft subsystems (propellant, antennas,                magnetosphere. Atmospheric drag. Atomic oxygen.
 transmitters, solar arrays, batteries). Real examples       Radiation belts and shielding.
 are used to permit an understanding of the systems             3. Orbital Mechanics And Mission Design. Motion
 selection and trade-off issues in the design process.       in gravitational field. Elliptic orbit. Classical orbit
 The fundamentals of subsystem technologies provide          elements. Two-line element format. Hohmann transfer.
 an indispensable basis for system engineering. The          Delta-V requirements. Launch sites. Launch to
 basic nomenclature, vocabulary, and concepts will           geostationary orbit. Orbit perturbations. Key orbits:
 make it possible to converse with understanding with        geostationary, sun-synchronous, Molniya.
 subsystem specialists.                                         4. Space Mission Geometry. Satellite horizon,
    The course is designed for engineers and managers        ground track, swath. Repeating orbits.
 who are involved in planning, designing, building,             5. Spacecraft And Mission Design Overview.
 launching, and operating space systems and                  Mission design basics. Life cycle of the mission.
 spacecraft subsystems and components. The                   Reviews. Requirements. Technology readiness levels.
 extensive set of course notes provide a concise             Systems engineering.
 reference for understanding, designing, and operating          6. Mission Support. Ground stations. Deep
 modern spacecraft. The course will appeal to engineers      Space Network (DSN). STDN. SGLS. Space Laser
 and managers of diverse background and varying              Ranging (SLR). TDRSS.
 levels of experience.                                          7. Attitude Determination And Control.
                                                             Spacecraft attitude. Angular momentum. Environmental
                                                             disturbance torques. Attitude sensors. Attitude control
                      Instructor                             techniques (configurations). Spin axis precession.
    Dr. Mike Gruntman is Professor of Astronautics at        Reaction wheel analysis.
 the University of Southern California. He is a specialist      8. Spacecraft          Propulsion.        Propulsion
 in astronautics, space technology, sensors, and space       requirements. Fundamentals of propulsion: thrust,
 physics. Gruntman participates in several theoretical       specific impulse, total impulse. Rocket dynamics:
 and experimental programs in space science and              rocket equation. Staging. Nozzles. Liquid propulsion
 space technology, including space missions. He              systems. Solid propulsion systems. Thrust vector
 authored and co-authored more 200 publications in           control. Electric propulsion.
 various areas of astronautics, space physics, and              9. Launch Systems. Launch issues. Atlas and
 instrumentation.                                            Delta launch families. Acoustic environment. Launch
                                                             system example: Delta II.
               What You Will Learn                             10. Space Communications. Communications
                                                             basics. Electromagnetic waves. Decibel language.
  • Common space mission and spacecraft bus
                                                             Antennas. Antenna gain. TWTA and SSA. Noise. Bit
    configurations, requirements, and constraints.
                                                             rate. Communication link design. Modulation
  • Common orbits.                                           techniques. Bit error rate.
  • Fundamentals of spacecraft subsystems and their            11. Spacecraft Power Systems. Spacecraft power
    interactions.                                            system elements. Orbital effects. Photovoltaic systems
  • How to calculate velocity increments for typical         (solar cells and arrays). Radioisotope thermal
    orbital maneuvers.                                       generators (RTG). Batteries. Sizing power systems.
  • How to calculate required amount of propellant.            12. Thermal Control. Environmental loads.
                                                             Blackbody concept. Planck and Stefan-Boltzmann
  • How to design communications link..
                                                             laws. Passive thermal control. Coatings. Active thermal
  • How to size solar arrays and batteries.
                                                             control. Heat pipes.
  • How to determine spacecraft temperature.
                                   Register online at www.ATIcourses.com or call ATI at 888.501.2100 or 410.956.8805
60 – Vol. 97
www.ATIcourses.com

Boost Your Skills                                             349 Berkshire Drive
                                                              Riva, Maryland 21140
with On-Site Courses                                          Telephone 1-888-501-2100 / (410) 965-8805

Tailored to Your Needs
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                                                              Email: ATI@ATIcourses.com

The Applied Technology Institute specializes in training programs for technical professionals. Our courses keep you
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on-site training at the major Navy, Air Force and NASA centers, and for a large number of contractors. Our training
increases effectiveness and productivity. Learn from the proven best.

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            Space Systems Fundamentals



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Mike Gruntman              Space Systems Fundamentals – Part 02. Universe. … Coordinate systems



      Coordinate Systems

Coordinate systems play an
exceptionally important role in
exploration of space.      They
provide the means to describe
complicated motions of celestial
bodies and spacecraft.

The most commonly used
coordinate system in science and
engineering is the Cartesian
coordinate system formed by
three orthogonal (perpendicular
to each other) vectors x,y,z. The
coordinate system that is used
                                         In the spherical coordinate system, one
most often in space (and in
                                        describes a position of a point by a distance
astronomy as well) is the
                                        from the center of coordinates and two angles
spherical coordinate system.
                                        between the direction to the point and two
                                        coordinate-system-specific reference vectors.
   2006 by Mike Gruntman            2006_06_MG_SSF_Part_02                               13/20
Mike Gruntman                Space Systems Fundamentals – Part 02. Universe. … Coordinate systems




         Coordinate Systems
                                                  •   Reference vectors
                                                            reference vector selection determines
                                                            the reference plane (normal to the
                                                            vector)
     •      Center                                          associated with natural phenomena
                                                            (provided by nature)
            Depending on
                                                              • rotation of the earth about its axis
            application, the center of
            the coordinate system is                             defines the equatorial plane
            selected in such a way                            • motion of the earth around the sun
            as to simplify the
                                                                 defines the ecliptic plane
            description of particle
                                                            assumed fixed in inertial space
            (spacecraft) motion:
                                                              • in reality, precession
                 geocentric
                                                            reference vectors are preferred to be
                 heliocentric
                                                            perpendicular to each other
                 planetocentric
                                                              • how do we define the second
                 center of galaxy
                                                                 vector?
                 ….

         2006 by Mike Gruntman            2006_06_MG_SSF_Part_02                                14/20




     Mike Gruntman                Space Systems Fundamentals – Part 02. Universe. … Coordinate systems




     Ecliptic
      and
    Equatorial
     Planes


•   The plane, which contains the earth’s orbit around the sun, is called the ecliptic plane.
    Obviously, the sun is in this plane. The axis of the earth’s rotation around the sun (and
    correspondingly the ecliptic plane) is fixed in inertial space (except for small precession).
•   An angle between the orbital plane of a planet and the ecliptic plane is called the
    inclination of the orbital plane. The orbits of the planets are close to the ecliptic plane,
    except those of Mercury and especially Pluto.
•   The Earth rotates about its axis (which defines the South-North direction). This axis of
    rotation is fixed in inertial space (except for small precession) and its direction does not
    change as earth moves around the sun.
•   The axis of rotation is not perpendicular (normal) to the ecliptic plane; the angle between
    the axis of earth’s rotation and direction perpendicular to the ecliptic plane is 23.5 . This
    inclination of the axis is the most important factor “responsible” for the seasons.

         2006 by Mike Gruntman            2006_06_MG_SSF_Part_02                                15/20
Mike Gruntman               Space Systems Fundamentals – Part 02. Universe. … Coordinate systems



                              Vernal Equinox Vector




      2006 by Mike Gruntman             2006_06_MG_SSF_Part_02                                16/20




    Mike Gruntman               Space Systems Fundamentals – Part 02. Universe. … Coordinate systems




        Vernal
       Equinox
        Vector


•   The vernal equinox is a reference vector to establish longitude in both celestial and
    heliocentric systems of coordinates.
•   There are two equinoxes each year, in the spring and in the fall. At equinox, earth is
    located at the intersection line of the equatorial and ecliptic planes. The equinox in the
    spring (around March 21) is called the vernal equinox; the equinox in the fall – the
    autumnal equinox.
•   The direction from the center of mass of the Earth to the center of the sun at the vernal
    equinox is the reference vector (the vernal equinox vector) to determine longitude.
•   The vernal equinox was first established thousands of years ago. At that time the vernal
    equinox vector passed through constellation of Aries (The Ram). The astronomical sign
    of the Ram, , is still used for the vernal equinox vector although over the years the
    vector moved to Pisces (The Fishes).
•   The equinox vector precession rate is 0.014 degrees per year …. Why does it happen?
      2006 by Mike Gruntman             2006_06_MG_SSF_Part_02                                17/20
Mike Gruntman                 Space Systems Fundamentals – Part 02. Universe. … Coordinate systems



                            Coordinate Systems
•      Geocentric Celestial
          For a spacecraft orbiting the Earth, it would be convenient to use the
          system of coordinate with the center at the Earth’s center and using the
          Earth’s equator as a reference plane. Such a coordinate system is called
          the geocentric system of coordinates (see figure). The equatorial plane is
          the reference plane and the X-axis is the vernal equinox vector.
•      Heliocentric
           For a spacecraft traveling from one planet to another, say from Earth to
           Jupiter, it would be convenient to place the center of the coordinate system
           at the Sun and use the ecliptic plane as a reference plane. Such a
           coordinate system is called the heliocentric system of coordinates. The
           equatorial plane is inclined at an angle 23.5 with respect to the ecliptic.
•      Galactic
           For determining position of stars belonging to our galaxy, it would be
           convenient to use the galactic plane as a reference plane. Such a
           coordinate system is called the galactic system of coordinates.
•      Space missions typically require use of various systems of coordinates


    2006 by Mike Gruntman             2006_06_MG_SSF_Part_02                                18/20




Mike Gruntman                 Space Systems Fundamentals – Part 02. Universe. … Coordinate systems



                                              Time
Apparent Solar Time                                Mean solar time
•      One day is determined as an                 •    This is the time that you have on your
       interval between two successive                  watch.
       high noons (two successive solar            •    It assumes a circular orbit of the Earth,
       transits across a local meridian).               the spin axis normal to the ecliptic
       The problem is that all days are                 plane, no axis-wobbling, etc.
       slightly different because                  •    A mean solar day is equal to exactly
             Earth’s orbit is not exactly               24 hours or 1440 minutes or
             circular                                   86,400 seconds
             Earth rotates around the Sun          Universal Time
             Earth rotates about its axis
                                                   •    The mean solar time at Greenwich
             the spin axis is not normal to             (England) is called the Universal Time
             the ecliptic plane                         (UT).
             Earth’s axis slightly wobbles         •    Scientific data obtained from
•      All these effects are small and                  spacecraft are very often time-tagged
       predictable. So it is possible to                using the UT system.
       build a time scale based on the
       mean motion of the Earth relative
       the Sun, mean solar time.

    2006 by Mike Gruntman             2006_06_MG_SSF_Part_02                                19/20
Mike Gruntman                Space Systems Fundamentals – Part 02. Universe. … Coordinate systems



     Sidereal Time




•      In this time scale, the motion of the Earth relative to the stars determines the
       time. A sidereal day is slightly different from the mean solar day.
            This difference is illustrated in figure.
•      A mean solar day = 1.0027379 mean sidereal day.
•      1 sidereal day = 23 hr 56 min 4.09 sec
•      Spacecraft in geostationary orbit (GEO)

    2006 by Mike Gruntman            2006_06_MG_SSF_Part_02                                20/20

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Space Systems Fundamentals

  • 1. Professional Development Short Course On: Space Systems Fundamentals Instructor: Dr. Mike Gruntman http://www.ATIcourses.com/schedule.htm ATI Course Schedule: http://www.aticourses.com/space_systems_fundamentals.htm ATI's Space Systems Fundamentals: 349 Berkshire Drive • Riva, Maryland 21140 888-501-2100 • 410-956-8805 Website: www.ATIcourses.com • Email: ATI@ATIcourses.com
  • 2. Space Systems Fundamentals NEW! May 18-21, 2009 Albuquerque, New Mexico June 22-25, 2009 Beltsville, Maryland $1590 (9:00am - 4:30pm) quot;Register 3 or More & Receive $10000 each Summary Off The Course Tuition.quot; This four-day course provides an overview of the fundamentals of concepts and technologies of modern spacecraft systems design. Satellite system and mission design is an essentially interdisciplinary sport Course Outline that combines engineering, science, and external phenomena. We will concentrate on scientific and 1. Space Missions And Applications. Science, engineering foundations of spacecraft systems and exploration, commercial, national security. Customers. interactions among various subsystems. Examples 2. Space Environment And Spacecraft show how to quantitatively estimate various mission Interaction. Universe, galaxy, solar system. elements (such as velocity increments) and conditions Coordinate systems. Time. Solar cycle. Plasma. (equilibrium temperature) and how to size major Geomagnetic field. Atmosphere, ionosphere, spacecraft subsystems (propellant, antennas, magnetosphere. Atmospheric drag. Atomic oxygen. transmitters, solar arrays, batteries). Real examples Radiation belts and shielding. are used to permit an understanding of the systems 3. Orbital Mechanics And Mission Design. Motion selection and trade-off issues in the design process. in gravitational field. Elliptic orbit. Classical orbit The fundamentals of subsystem technologies provide elements. Two-line element format. Hohmann transfer. an indispensable basis for system engineering. The Delta-V requirements. Launch sites. Launch to basic nomenclature, vocabulary, and concepts will geostationary orbit. Orbit perturbations. Key orbits: make it possible to converse with understanding with geostationary, sun-synchronous, Molniya. subsystem specialists. 4. Space Mission Geometry. Satellite horizon, The course is designed for engineers and managers ground track, swath. Repeating orbits. who are involved in planning, designing, building, 5. Spacecraft And Mission Design Overview. launching, and operating space systems and Mission design basics. Life cycle of the mission. spacecraft subsystems and components. The Reviews. Requirements. Technology readiness levels. extensive set of course notes provide a concise Systems engineering. reference for understanding, designing, and operating 6. Mission Support. Ground stations. Deep modern spacecraft. The course will appeal to engineers Space Network (DSN). STDN. SGLS. Space Laser and managers of diverse background and varying Ranging (SLR). TDRSS. levels of experience. 7. Attitude Determination And Control. Spacecraft attitude. Angular momentum. Environmental disturbance torques. Attitude sensors. Attitude control Instructor techniques (configurations). Spin axis precession. Dr. Mike Gruntman is Professor of Astronautics at Reaction wheel analysis. the University of Southern California. He is a specialist 8. Spacecraft Propulsion. Propulsion in astronautics, space technology, sensors, and space requirements. Fundamentals of propulsion: thrust, physics. Gruntman participates in several theoretical specific impulse, total impulse. Rocket dynamics: and experimental programs in space science and rocket equation. Staging. Nozzles. Liquid propulsion space technology, including space missions. He systems. Solid propulsion systems. Thrust vector authored and co-authored more 200 publications in control. Electric propulsion. various areas of astronautics, space physics, and 9. Launch Systems. Launch issues. Atlas and instrumentation. Delta launch families. Acoustic environment. Launch system example: Delta II. What You Will Learn 10. Space Communications. Communications basics. Electromagnetic waves. Decibel language. • Common space mission and spacecraft bus Antennas. Antenna gain. TWTA and SSA. Noise. Bit configurations, requirements, and constraints. rate. Communication link design. Modulation • Common orbits. techniques. Bit error rate. • Fundamentals of spacecraft subsystems and their 11. Spacecraft Power Systems. Spacecraft power interactions. system elements. Orbital effects. Photovoltaic systems • How to calculate velocity increments for typical (solar cells and arrays). Radioisotope thermal orbital maneuvers. generators (RTG). Batteries. Sizing power systems. • How to calculate required amount of propellant. 12. Thermal Control. Environmental loads. Blackbody concept. Planck and Stefan-Boltzmann • How to design communications link.. laws. Passive thermal control. Coatings. Active thermal • How to size solar arrays and batteries. control. Heat pipes. • How to determine spacecraft temperature. Register online at www.ATIcourses.com or call ATI at 888.501.2100 or 410.956.8805 60 – Vol. 97
  • 3. www.ATIcourses.com Boost Your Skills 349 Berkshire Drive Riva, Maryland 21140 with On-Site Courses Telephone 1-888-501-2100 / (410) 965-8805 Tailored to Your Needs Fax (410) 956-5785 Email: ATI@ATIcourses.com The Applied Technology Institute specializes in training programs for technical professionals. Our courses keep you current in the state-of-the-art technology that is essential to keep your company on the cutting edge in today’s highly competitive marketplace. Since 1984, ATI has earned the trust of training departments nationwide, and has presented on-site training at the major Navy, Air Force and NASA centers, and for a large number of contractors. Our training increases effectiveness and productivity. Learn from the proven best. For a Free On-Site Quote Visit Us At: http://www.ATIcourses.com/free_onsite_quote.asp For Our Current Public Course Schedule Go To: http://www.ATIcourses.com/schedule.htm
  • 4. You have enjoyed an ATI's preview of Space Systems Fundamentals Please post your comments and questions to our blog: http://www.aticourses.com/wordpress-2.7/weblog1/ Sign-up for ATI's monthly Course Schedule Updates : http://www.aticourses.com/email_signup_page.html
  • 5. Mike Gruntman Space Systems Fundamentals – Part 02. Universe. … Coordinate systems Coordinate Systems Coordinate systems play an exceptionally important role in exploration of space. They provide the means to describe complicated motions of celestial bodies and spacecraft. The most commonly used coordinate system in science and engineering is the Cartesian coordinate system formed by three orthogonal (perpendicular to each other) vectors x,y,z. The coordinate system that is used In the spherical coordinate system, one most often in space (and in describes a position of a point by a distance astronomy as well) is the from the center of coordinates and two angles spherical coordinate system. between the direction to the point and two coordinate-system-specific reference vectors. 2006 by Mike Gruntman 2006_06_MG_SSF_Part_02 13/20
  • 6. Mike Gruntman Space Systems Fundamentals – Part 02. Universe. … Coordinate systems Coordinate Systems • Reference vectors reference vector selection determines the reference plane (normal to the vector) • Center associated with natural phenomena (provided by nature) Depending on • rotation of the earth about its axis application, the center of the coordinate system is defines the equatorial plane selected in such a way • motion of the earth around the sun as to simplify the defines the ecliptic plane description of particle assumed fixed in inertial space (spacecraft) motion: • in reality, precession geocentric reference vectors are preferred to be heliocentric perpendicular to each other planetocentric • how do we define the second center of galaxy vector? …. 2006 by Mike Gruntman 2006_06_MG_SSF_Part_02 14/20 Mike Gruntman Space Systems Fundamentals – Part 02. Universe. … Coordinate systems Ecliptic and Equatorial Planes • The plane, which contains the earth’s orbit around the sun, is called the ecliptic plane. Obviously, the sun is in this plane. The axis of the earth’s rotation around the sun (and correspondingly the ecliptic plane) is fixed in inertial space (except for small precession). • An angle between the orbital plane of a planet and the ecliptic plane is called the inclination of the orbital plane. The orbits of the planets are close to the ecliptic plane, except those of Mercury and especially Pluto. • The Earth rotates about its axis (which defines the South-North direction). This axis of rotation is fixed in inertial space (except for small precession) and its direction does not change as earth moves around the sun. • The axis of rotation is not perpendicular (normal) to the ecliptic plane; the angle between the axis of earth’s rotation and direction perpendicular to the ecliptic plane is 23.5 . This inclination of the axis is the most important factor “responsible” for the seasons. 2006 by Mike Gruntman 2006_06_MG_SSF_Part_02 15/20
  • 7. Mike Gruntman Space Systems Fundamentals – Part 02. Universe. … Coordinate systems Vernal Equinox Vector 2006 by Mike Gruntman 2006_06_MG_SSF_Part_02 16/20 Mike Gruntman Space Systems Fundamentals – Part 02. Universe. … Coordinate systems Vernal Equinox Vector • The vernal equinox is a reference vector to establish longitude in both celestial and heliocentric systems of coordinates. • There are two equinoxes each year, in the spring and in the fall. At equinox, earth is located at the intersection line of the equatorial and ecliptic planes. The equinox in the spring (around March 21) is called the vernal equinox; the equinox in the fall – the autumnal equinox. • The direction from the center of mass of the Earth to the center of the sun at the vernal equinox is the reference vector (the vernal equinox vector) to determine longitude. • The vernal equinox was first established thousands of years ago. At that time the vernal equinox vector passed through constellation of Aries (The Ram). The astronomical sign of the Ram, , is still used for the vernal equinox vector although over the years the vector moved to Pisces (The Fishes). • The equinox vector precession rate is 0.014 degrees per year …. Why does it happen? 2006 by Mike Gruntman 2006_06_MG_SSF_Part_02 17/20
  • 8. Mike Gruntman Space Systems Fundamentals – Part 02. Universe. … Coordinate systems Coordinate Systems • Geocentric Celestial For a spacecraft orbiting the Earth, it would be convenient to use the system of coordinate with the center at the Earth’s center and using the Earth’s equator as a reference plane. Such a coordinate system is called the geocentric system of coordinates (see figure). The equatorial plane is the reference plane and the X-axis is the vernal equinox vector. • Heliocentric For a spacecraft traveling from one planet to another, say from Earth to Jupiter, it would be convenient to place the center of the coordinate system at the Sun and use the ecliptic plane as a reference plane. Such a coordinate system is called the heliocentric system of coordinates. The equatorial plane is inclined at an angle 23.5 with respect to the ecliptic. • Galactic For determining position of stars belonging to our galaxy, it would be convenient to use the galactic plane as a reference plane. Such a coordinate system is called the galactic system of coordinates. • Space missions typically require use of various systems of coordinates 2006 by Mike Gruntman 2006_06_MG_SSF_Part_02 18/20 Mike Gruntman Space Systems Fundamentals – Part 02. Universe. … Coordinate systems Time Apparent Solar Time Mean solar time • One day is determined as an • This is the time that you have on your interval between two successive watch. high noons (two successive solar • It assumes a circular orbit of the Earth, transits across a local meridian). the spin axis normal to the ecliptic The problem is that all days are plane, no axis-wobbling, etc. slightly different because • A mean solar day is equal to exactly Earth’s orbit is not exactly 24 hours or 1440 minutes or circular 86,400 seconds Earth rotates around the Sun Universal Time Earth rotates about its axis • The mean solar time at Greenwich the spin axis is not normal to (England) is called the Universal Time the ecliptic plane (UT). Earth’s axis slightly wobbles • Scientific data obtained from • All these effects are small and spacecraft are very often time-tagged predictable. So it is possible to using the UT system. build a time scale based on the mean motion of the Earth relative the Sun, mean solar time. 2006 by Mike Gruntman 2006_06_MG_SSF_Part_02 19/20
  • 9. Mike Gruntman Space Systems Fundamentals – Part 02. Universe. … Coordinate systems Sidereal Time • In this time scale, the motion of the Earth relative to the stars determines the time. A sidereal day is slightly different from the mean solar day. This difference is illustrated in figure. • A mean solar day = 1.0027379 mean sidereal day. • 1 sidereal day = 23 hr 56 min 4.09 sec • Spacecraft in geostationary orbit (GEO) 2006 by Mike Gruntman 2006_06_MG_SSF_Part_02 20/20