Zou Ziming1 Ma Wenzhen Li Lei Zhao Hua Wang Chi

1: mzou@cssar.ac.cn

Center for Space Science and Applied Research

Chinese Academy of Sciences

Moscow · Oct 11-16, 2010

Overview of the YH-1 Science Data SystemOverview of the YH-1 Science Data System

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

2

1. Objectives of YH-1 Science Data System1. 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

3

2. Infrastructure of YH-1 Science Data System2. Infrastructure of YH-1 Science Data System

4

• Components of YH-1 SDS

ComponentComponent 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.

5

• Hardware platform of YH-1 SDS

6

3. Science3. Science Data PipelineData Pipeline

7

• 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 00:00:00-23:59:59) 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.

8

4. Science Data Products Specification4. Science Data Products Specification

Instrument / MeasurementLevel 1

(Raw)

Level 2(Edited)

Level 3(Calibrated

)

Level 4(Resampled)

Level 5(Derived)

Flux-gate Magnetometer

Sensor A

√

√ √√

Sensor B √ √

Plasma Package

Electron Analyzer √ √

Ion Energy and Mass Analyzer I

√ √

Ion Energy and Mass Analyzer II

√ √

Optical ImagerImager 1 √ √

Imager 2 √ √

Occultation Experiment

Sat-Sat Occultation Receiver

√ √

Sat-Ground Occultation Experiment

√ √

Raw data: downlink instruments raw data, sat-ground occultation experiment raw data.

Data Products: 18 kinds of science data products (from L2 to L5).

9

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.

• Data products of flux-gate magnetometer

10

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.

• Data products of plasma package

11

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.

• Data products of optical imager

12

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).

• Data products of occultation experiment

13

• An example of optical imager data archive structure

5. Data Archiving5. Data Archiving

Optical Imager Data Set Collection

CALIBCATALOG DATA DOCUMENTGEOMETRY

CCD2 L4 RDR DATA SET ……

INDEX

MONYYYY

DATA-1

Processing reports,Exploration plans,Spacecraft clock correlation files,

…

Science data files and labels

Calibration files and labels

Spacecraft trajectory files, Spacecraft orientation files

and labels

CCD1 L4 RDR DATA SET

CATINFO.TXTDATASET.CATRELEASE.CATPERSON.CATINST.CAT

INSTHOST.CATMISSION.CAT

Index file

14

5. How to access the Science Archives5. 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

15

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.16

17

Thank you very much for your attention !