Onboard Science Instruments

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• Onboard Science Instruments
• Yasuhiko Takagi
• Aichi Toho University
• Joint Discussion on European-Japanese Sample
  Return mission to a small solar system body
• March 27, 2007, JAXA Nihonbashi Office

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Objectives

• The objectives of onboard science instruments are
  summarized as
• (1) investigation of target asteroid
• (2) support of sampling site selection
• (3) description of sampling site
• to clarify the source of returned samples

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Possible Instruments

• Surface Topology/Morphology
• Optical Camera, 2D Scan LIDAR
• Mineralogy/Chemistry
• Spectrometers (Near-Infrared, X-ray, g-ray)
• Internal Structure
• Ground Penetration Radar, Seismometer,
• Gravity measurement
• Outer Environment
• Dust detector/counter, UV Imager

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Optical Camera
Common with Optical Navigation Camera
Optics Refracting telescope Focal length TBD
Detector CCD (1 k1 k pixel) Field of view 5
degrees Science Instruments Color Filter ECAS
or Johnson Polarizer TBD Close-up Lens
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2D Scan LIDAR
Ranging 30 km 50 m Resolution 1 m Sampling
rate 1 Hz Scan angle 5 10 degrees Laser Passive
Q-SW Nd-YAG RX Optics Refracting Telescope Field
of view 0.51 mrad Scan mechanism MEMS
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Near-Infrared Spectrometer

• Objectives
• Observation of mineralogical variation on the
  target body
• Detection of hydrous mineral and organic matter
• Wavelength 0.3 3.5 mm
• Detector InAs Si 2D Array
• Disperser Grism or Grating

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X-Ray Spectrometer
Target elements Mg, Al, Si, S, (Fe), (Ca, Ti)
Solar Flare Period Detector X-ray
CCD Optics Collimator or Capillary-Plate Solar
X-ray monitor Direct observation by PIN
Standard Sample
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g-Ray Spectrometer
Target elements Radioactive Th series, U
series, K .... Major Fe, Ti, O, Si, Ca, Al,
Mg, Na Volatile H, (S), (C), Detector Pure
Ge Cooling Stirling Engine
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Gravity Measurements
Precise determination of distance between lander
or rover and spacecraft using a transponder
Precise determination of the spacecraft using R
and RR, optical camera, and LIDAR data.