Zou Ziming1 Ma Wenzhen Li Lei Zhao Hua Wang Chi

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Overview of the YH-1 Science Data System

• Zou Ziming1 Ma Wenzhen Li Lei Zhao Hua Wang
  Chi
• 1 mzou_at_cssar.ac.cn
• Center for Space Science and Applied Research
• Chinese Academy of Sciences
• Moscow Oct 11-16, 2010

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OUTLINE

• Objectives of YH-1 Science Data System
• Infrastructure of YH-1 Science Data System
• The Science Data Pipeline of YH-1 Mars Mission
• The specification of YH-1 Science Data Products
• Data Archiving and How to Access to the Archives

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1. Objectives of YH-1 Science Data System

• Process the down-linked raw data to
  PDS3-compliant high quality higher level data
  products
• Collect suitable organized and well-documented
  YH-1 science data products into PDS3-compliant
  YH-1 science data archives that would be
  peer-reviewed, make them available and useful to
  users
• Provide online YH-1 science data access to the
  international planetary science communities
• Ensure the long-term preservation of the data
  products and maintain their usability

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2. Infrastructure of YH-1 Science Data System
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Components of YH-1 SDS
Component Function Description
Raw Data Collecting Collecting L1 raw data from Scientific Operation Center (SOC).
Raw Data Pre-processing Picking-up instrument data from L1 raw data, and generating L2 edited instrument data after time-ordering, duplicates and errors removing, etc.
High Level Data Products Processing and Inverting Processing and inverting science data from L2 to higher levels through calibrating, resampling, derivation, etc., generating PDS3-compliant science data products.
YH-1 Scientific Database Data management and storage.
PDS Products Validating Validating the grammar and contents of data files and PDS Labels.
Data Products Archiving Archiving science data into data sets with necessary ancillary data compliant with PDS3 for long-term preservation.
Science Data Distributing Providing online science data access service to the international planetary science communities via the Internet.
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Hardware platform of YH-1 SDS
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3. Science Data Pipeline
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Overview of YH-1 science data level
Data level Identifier Description for processing level
Level 1 (Raw) L1 Raw packaged data downlink from YH-1 satellite received at different ground stations, with science and engineering data embedded.
Level 2 (Edited) L2 Instrument science data at full resolution, converted from binary to decimal (e.g., voltages, counts), time-ordered, splicing all data of once downlink from different ground stations together, with duplicates and errors removed, have been divided or merged based on Earth Day (UTC 000000-235959) or event.
Level 3 (Calibrated) L3 Level 2 data that have been located in space and have been transformed (e.g., calibrated, rearranged) in a reversible manner and packaged with needed ancillary and auxiliary data.
Level 4 (Resampled) L4 Irreversibly transformed (e.g., resampled, remapped, calibrated) values of the instrument measurements.
Level 5 (Derived) L5 Geophysical parameters mapped onto uniform space-time grids, commensurate with instrument location, pointing, and sampling, and may have additional corrections applied.
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4. Science Data Products Specification
Raw data downlink instruments raw data,
sat-ground occultation experiment raw data. Data
Products 18 kinds of science data products
(from L2 to L5).
Instrument / Measurement Instrument / Measurement Level 1 (Raw) Level 2 (Edited) Level 3 (Calibrated) Level 4 (Resampled) Level 5 (Derived)
Flux-gate Magnetometer Sensor A v v v v
Flux-gate Magnetometer Sensor B v v v v
Plasma Package Electron Analyzer v v v
Plasma Package Ion Energy and Mass Analyzer I v v v
Plasma Package Ion Energy and Mass Analyzer II v v v
Optical Imager Imager 1 v v v
Optical Imager Imager 2 v v v
Occultation Experiment Sat-Sat Occultation Receiver v v v
Occultation Experiment Sat-Ground Occultation Experiment v v
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• Data products of flux-gate magnetometer

• Probing objective of flux-gate magnetometer
• Magnetic field of Martian space environment
• Data products
• L2 data Corresponding voltage as sampled by the
  instrument (two probes), obtained after
  conversion of original binary code to a decimal
  corresponding voltage value.
• L3 data Space magnetic field strength of each
  probe (sensor A and sensor B), obtained after
  converting the corresponding voltage to actual
  voltage value, temperature correction and
  transforming the actual voltage data into
  magnetic field strength.
• L5 data Space magnetic field strength at the
  spacecraft position, obtained by eliminating the
  platform remanence by fusing the data from the
  two probes.

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• Data products of plasma package

• Probing objective of plasma package
• Plasma of Martian space
• Data products
• L2 data Counts as sampled by the instrument
  (three probes), obtained after conversion of
  original binary code to a decimal counts value.
• L3 data Electron flux and ion flux, obtained by
  converting the counts value to flux value.

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• Data products of optical imager

• Probing objective of optical imager
• Sandstorm and Mars surface imaging
• 200m finest resolution, FOV 38X38o, 20X20o.
• Data products
• L2 data Grayscale images in bmp format, 8 bit
  per pixel.
• L4 data RGB color images in bmp format, 24 bit
  per pixel.

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• Data products of occultation experiment

• Probing objective of occultation experiment
• Sat-sat occultation Martian midnight ionosphere
• Sat-ground occultation Martian atmosphere and
  daytime ionosphere
• Data products
• Sat-sat occultation
• L2 data Phase and amplitude.
• L5 data Electron density (Martian ionospheric
  parameters ).
• Sat-ground occultation
• L5 data Electron density, atmospheric
  temperature, atmospheric density and atmospheric
  pressure (Martian ionospheric and atmospheric
  parameters).

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5. Data Archiving

• An example of optical imager data archive
  structure

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5. How to access the Science Archives
Quick search area, input the condition to
retrieve the data set
Click on payload names, users can see its
products list
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A simulated data set list example, user can
directly browser or download the specific data
files and its labels, catalog files, calibration
files, geometry files or other documents.
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Thank you very much for your attention !