The ground application system defines and explains the released standard data products of the first Mars exploration mission, which can be served as the basis for the use of standard data products.

1.Abbreviation

Table 1-1: Scientific instrument abbreviation list

2.Scientific data product classification

The ground application system preprocesses the detection data of the scientific instrument carried by Tianwen-1, and produces standard data of various levels. The scientific data products released are level 2B or 2C.

Table 2-1: Definitions of the scientific data level

3.Data file naming

The naming specification of CE-5 data product is as follow：

HXX_st_pl_ty_dc_yyyymmddhhmiss_YYYYMMDDHHMISS_ob_ver.lv.Fields separated by ‘_’ mean.

3.1 Mission

HX1: mission identification, HX1-Or means Tianwen-1Orbiter, HX1-Ro means Tianwen-1 Rover..

3.2 Ground station

St means data source (ground station)，including GRAS and BACC；the st of lever 2B, 2C all are GRAS.

3.3 Scientific instrument

Pl means the abbreviation of scientific instruments，then added work mode and data number.

For example: MoRIC-F-001means the 1st image of MoRIC in full frame mode.。

The pl means can be check in Table 1.

3.4 Data products type

Ty means the type of data products：SCI—scientific data.

3.5 Time characteristic of data

dc means time characteristic of data:

R——Real-time data;

P——Playback data;

N——Indistinguishable data (mixed data).

3.6 Start time and end time

The start time and end time all are UTC, yyyymmddhhmiss means the start time, yyyy means year, mm means month, dd means day, hh means hour, mi means minute, ss means second.

YYYYMMDDHHMISS means the end time, YYYY means year, MM means month, DD means day, HH means hour, MI means minute, SS means second.

The start and end time of the level 2 data file is the time of the first record and the time of the last record in the data file. If the data is a single image, the start time and end time are the same, which is the actual acquisition time of this image.

3.7 Detection cycle number

In level 2 data, the 0b means detection cycle number, the value is 00001-99999.

3.8 Product version

ver means product version, from A to Z, the first version is A, the last version is Z.

3.9 Product level

lv means product level:

All levels of scientific data or auxiliary data suffix are 2B or 2C.

Corresponding PDS tag file suffixes are 2BL or 2CL.

4.Data product format description

The standard data product for the first Mars exploration mission was designed based on the Version 1.12.0 of the Planetary Data System Standards Reference published on the website in June 2019. Level 2 data products are stored in accordance with the specification Planetary Data System Standards Reference (Version 1.12.0, April, 2019), and the metadata information in the data label adopts the PDS data dictionary PDS4 Data Dictionary: Abridged-Version" 1.12.0.0. The following is a description of the released level 2 data products.

4.1 Level 2 data product structure

Level 2 data products consist of two parts: data label and data objec:

• 1)A data product contains only one data label, but it can contain multiple data objects;
• 2)Data tags and data objects are stored as separate files;
• 3)The data label adopts the file of XML format.
• 4)Scientific data is expressed as data objects. The TW-1 mission includes six types of data including image data, spectral data, radar detection data, magnetic field detection data, space environment detection data, and sound data.

4.1.1 MOSIR data storage structure

Each level 2B data product includes a data label and a Table_Binary type data object for storing scientific data and geometric positioning information.

Table 4-1：MOSIR data storage structure description

4.1.2 MINPA data storage structure

Each level 2B data product includes a data label and a Table_Character type data object for storing scientific data and geometric positioning information.

Table 4-2：MINPA data storage structure description

4.1.3 NaTeCam data storage structure

Each level 2C data product includes a data tag and an Array_3D_Image type data object for storing color images, the content of the frame header information and geometric positioning information.

Table 4-3：NaTeCam data storage structure description

4.1.4 RoPeR data storage structure

Each level 2B data product includes a data tag and a Table_Binary type data object for storing scientific data and geometric positioning information such as the position and attitude of the rover, and the landing point location information.

Table 4-4：RoPeR data storage structure description

4.1.5 MarSCoDe data storage structure description

Each level 2B data product contains a data label and a Table_Character type data object for storing spectral data, and the content of geometric positioning information.

Table 4-5：MarSCoDe data storage structure description

4.1.6 MCS data storage structure

Each level 2C data product contains a data label and a Table_Character type data object for storing air temperature, pressure, wind field, and geometric information such as sun incident angle and azimuth angle, and position of the rover and the location of the landing site.

Table 4-6：MCS data storage structure description

4.1.7 MoRIC data storage structure

Each 2C-level data product includes a data tag, a data object of type Array_3D_Image for storing color images, a data object of type Table_Character for storing the geometric positioning grid of the image.

Table 4-7：MoRIC data storage structure description

4.1.8 MMS data storage structure

Each Level 2B data product includes a data tag, a data object of type Array_3D_Spectrum for storing scientific data, a data object of type Table_Character for storing scientific data frame headers (auxiliary data), and a data object of type Table_Character for storing scientific data Geometrically position grid data.

Table 4-8：MMS data storage structure description

4.1.9 MSCam data storage structure

Each 2B-level data product includes a data tag, a data object of type Array_2D_Image for storing the image.

Table 4-9：MSCam data storage structure description

4.1.10 MEPA data storage structure

Each 2B-level data product includes a data tag, a data object of type Table_Character for storing the scientific data and geometric positioning information.

Table 4-10：MSCam data storage structure description

4.1.11 RoMAG data storage structure

Each 2C-level data product includes a data tag, a data object of type Table_Character for storing the scientific data.

Table 4-11：MSCam data storage structure description

4.1.12 HiRIC data storage structure

Each level 2B data product includes a data tag, a data object of type Array_2D_Image to store the scientific data, a data object of type Table_Character to store the geometrically positioned grid data, and a data object of type Table_Character to store the image frame header(auxiliary data);

Table 4-12：HiRIC data storage structure description

4.1.13 MOMAG data storage structure

Each 2C-level data product includes a data tag, a data object of type Table_Character for storing color images.

Table 4-13：MOMAG data storage structure description

4.2 Tianwen-1 data type description

4.2.1 Binary data type

TW-1 data products using binary storage include UnsignedLSB4, UnsignedLSB2, SignedLSB2，UnsignedMSB4, UnsignedMSB2, UnsignedByte, IEEE754LSBSingle， IEEE754MSBSingle, UnsignedBitString.

4.2.2 Character data type

TW-1 data products stored in character type include ASCII_Real, ASCII_String, ASCII_Integer，ASCII_Date_Time_YMD_UTC，ASCII_Numeric_Base16. Attribute values of Table_character data and tag both use the above data types .

5.Product list appendix

5.1 Product list of HiRIC

Note: XXX represents the type of product data, that is, DEM or DIM ; AAA represents resolution; BBBB represents frame number; ddmmssNdddmmssE represents the latitude and longitude position of the center of the frame, dd/ddd is degrees, mm is minutes, ss Is the second, N represents the location of the north latitude (ie N) or south latitude (ie S) identification, E represents the longitude identification (ie E, represents the east longitude, the value range is 0 ~ 360 °); V represents the version number.

5.2 Product list of MOSIR

Note: (-XXX) only for MOSIR-HFR and MOSIR-LFR data, corresponding to data with different time window sizes in different modes, such as MOSIR-HFR-095, corresponding to detection data with a time window size of 95μs in high frequency mode; MOSIR-LFR-120 , Corresponding to detection data with a time window of 120μs in low frequency mode; MOSIR-LFR-HFW, corresponding to high frequency waveform data in low frequency mode.

Level 2B：

MOSIR-H, represents altimetry data;

MOSIR-VLF, represents very low frequency detection data;

MOSIR-HFR, represents the original echo high-frequency data;

MOSIR- LFR, represents the original echo low-frequency data;

MOSIR-HFI, represents imaging echo high-frequency data (on-board processing result);

MOSIR-LFI, represents low-frequency imaging echo data (on-board processing result)

5.3 Product list of MINPA

Note 1：

MINPA–MOD1-DEF, represents the default mode (table address 003300);

MINPA–MOD2-DEF, represents the default mode (table address F02D00);

MINPA–MOD3-HER, represents high energy resolution mode (table address 017400);

MINPA–MOD4-MT, represents the magnetic tail mode (table address 005F00);

MINPA–MOD5-LEI, represents low-energy ion mode (table address F13E00);

MINPA–MOD6-HTR, represents high time resolution mode (table address 01BD00);

MINPA–MOD7-FR, represents full resolution mode (table address 00AC00);

MINPA–MOD8-FR, represents full resolution mode (table address F0B000);

MINPA–MOD9-SW, represents solar wind mode (table address 00FF00);

MINPA–MOD10-SW, represents solar wind mode (table address F10300);

MINPA–MOD11-SW, represents solar wind mode (table address F06C00);

MINPA–MOD12-I, represents the ionospheric mode (table address 013A00);

MINPA–MOD13-NP, represents the neutral particle mode (table address 017100);

Note 2:

In addition to the above products, MINPA also includes a description file of calibration parameters. The file describes the correspondence between the pitch angle number and the angle center value and the center energy of ions and neutral particles in different modes. The file is named Calibration data description.pdf is quoted in the reference list field of the data label.

5.4 Product list of NaTeCam

5.5 Product list of RoPeR

Level 2B：

RoPeR-LF-R, represents the real part mode data of the low frequency channel;

RoPeR-LF-RI, represents the real and imaginary mode data of the low-frequency channel;

RoPeR-HF-HH, represents the HH polarization data of the high frequency channel;

RoPeR-HF-HV, represents HV polarization data of high frequency channel;

RoPeR-HF-VH, represents the high frequency channel VH polarization data;

RoPeR-HF-VV, represents the high frequency channel VV polarization data.

5.6 Product list of MCS

Note: Ro represents the lander and rover; RPCU represents the Mars rover load controller; MCS-Tra represents conventional measurement data; MCS-Man represents maneuver measurement data; MCS-Audio represents sound data

5.7 Product list of MoRIC

5.8 Product list of MMS

5.9 Product list of MSCam

MSCam-W-1 represents multispectral camera 1-channel data (windowed image data)

MSCam-W-2 represents the 2-channel data of the multispectral camera, and so on to the 8th channel (windowing image data)

MSCam-W-P represents multispectral camera panchromatic channel data (windowed image data)

5.10 Product list of MEPA

5.11 Product list of RoMAG

5.12 Product list of HiRIC