LRO Mission Baseline Ephemeris v10'0

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LRO Mission Baseline Ephemerisv10.0

• Released July 1, 2009
• Mark Beckman

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Baseline Ephemeris

• LRO Mission Baseline Ephemeris is the baseline
  reference trajectory for the LRO mission
• Whats in v10.0?
• Same format as previous versions
• Consistent with actual launch date of June 18,
  2009 (p30 case)
• Ephemeris starts at beginning of Commissioning
  Orbit
• No transfer orbit ephems

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File 1 Description

• File 1 (LRO_Mission_Baseline_Ephemeris_v9_file1.tx
  t)
• Time (Julian Date)
• Line every 5 minutes
• LRO Osculating Cartesian Position and Velocity
• (km) and (km/sec)
• Moon Centered Fixed coordinate frame
• Defined by DE421 Principal Axis frame
• LRO Right Ascension (deg) and Declination (deg)
• Moon Centered Mean J2000 coordinate frame
• Declination positive to Mean J2000 Z axis
• Lunar Altitude (km)
• From mean lunar sphere
• Lunar Latitude (deg) Longitude (deg)
• DE421 Principal Axis frame
• Lunar Ground Track Velocity (km/sec)
• Local Solar Time (deg)
• Angle between Moon-Sun vector and Moon-LRO vector
  measured about north ecliptic
• Solar Zenith Time (deg)
• Angle between Moon-Sun vector and Moon-LRO vector

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File 2 Description

• File 2 (LRO_Mission_Baseline_Ephemeris_v9_file2.tx
  t)
• Time (Julian Date) of Lunar Equator Ascending
  Node
• Line each ascending node
• Starts at first lunar ascending node after LOI-1
• Osculating Semi-Major Axis (km)
• Osculating Eccentricity
• Osculating Inclination (deg)
• Osculating Argument of Periapsis (deg)
• Lunar Ground Track Velocity (km/sec)
• Local Solar Time (deg)
• Solar Zenith Time (deg)
• Orbit Beta Angle (deg)
• Angle between orbit plane and Sun

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SPK Files

• Nominal Mission SPK file
• LRO_Mission_Baseline_Ephemeris_v9.bsp
• Moon centered
• Type 13
• Interpolation order 11
• LRO SPICE ID of -85