Observations

1
Observations

• Passive Natural Signals
• Photographs
• Semi-Passive Artificial Signals
• GPS receiver
• Active Signals Controlled by Observers
• Radar Echo, Laser Ranging

2
Passive Observations

• Astrographs 2-dim. Angles
• Photographic Plates, CCD Arrays, VTR
• Transit, Meridian Circle 1-dim. Angle
• Interferometry Precise 1-dim. Angle
• VLBI, Optical/IR Int., X-ray
• Ground-based vs Orbital platform

3
Passive Observations (Cont.)

• Detectors Arrival Time, Energy
• Photo-Multiplier Tube, Photo-Diode, CCD, Chamber
• Clocks Event Time
• Eclipse, Occultation, Pulse, Light Curve,
  Rise/Decay Pattern
• Doppler Radial Velocity
• Spectrograph, Emission/Absorption Lines

4
Semi-Passive Observations

• Doppler
• Up/Down Link to Satellites/Space Vehicles
• Integrated Doppler
• NNSS, DORIS/PRARE
• Semi-Passive VLBI
• ALSEP, RISE
• Time Difference
• GPS, GLONASS

5
Active Observations

• Radar Bombing
• Mercury, Venus, Mars, Asteroids
• Range and Range Rate (RRR)
• Artificial Satellites, Space Vehicles
• Radio Transponder
• Laser Ranging
• Satellite, Moon