Overview of Chandrayaan-1 PDS (Planetary Data System) Products

Home , Mars Orbiter Mission, Moon Impact Probe

Chandrayaan-1 PDS Data Products Archival Generation and Browse

By Ajay Kumar Prashar HRDPD/SIPG Chandrayaan-1 SAC Data Processing Team Contents

• ISDA (ISRO Science Data Archive) Overview • PDS (Planetary Data System) Overview • Mission & instrument Overview • Archive Process • Data Products Definitions • Data Products Archive Generation • Archive Organization : Mission & Instrument level • Visualizations of PDS Data Products (Ch1PDSViewer/NASAVIEW/USGS-ISIS) • Chandrayaan-1 Browse Application ISDA – Overview

 Central repository for all scientific and engineering data returned by ISRO’s planetary missions  Established at Indian Space Science Data Centre (ISSDC) Bangalore - in 2008.  ISDA archives data sets from following missions:  Chandrayaan-1  Mars Orbiter Mission  Astrosat  Chandrayaan-2 (Future)  ISDA adopted PDS as archive standard for generating mission & instrument specific data sets for the scientific user community  ISDA provides international collaboration with IPDA (International Planetary Data Alliance) PDS - Overview

Well known Archive standard for all the NASA planetary missions in the scientific user community.

 Adopted by ESA, JAXA and other space agencies across globe.  Features of PDS  Self structured, documented & Peer Review Data Sets  Long-term access and usability of data  ISRO had also adopted PDS3 for following missions  Chandrayaan-1  Mars Orbiter Mission.  ISRO will adopt PDS4 for Chandrayaan-2 and continue PDS4 for future planetary missions.  PDS Home Page (http://pds.nasa.gov) Mission & Instruments – Overview  Chandrayaan-1, India’s first mission to Moon, was launched successfully on 22 October 2008 from SDSC SHAR, Sriharikota.  Spacecraft was orbiting around Moon at a height of 100 km from the lunar surface for chemical, mineralogical and photo-geologic mapping of the Moon.  Spacecraft carried 11 scientific instruments built in India, USA, UK,Germany, Sweden and Bulgaria.  Satellite made more than 3400 orbits around the moon.  Mission duration : Nov. 2008 to Aug. 2009.  Instruments:  Terrain Mapping Camera (TMC)  Hyper Spectral Imager (HySI)  Lunar Laser Ranging Instrument (LLRI)  High Energy X-ray Spectrometer (HEX)  Moon Impact Probe (MIP)  Chandrayaan-1 X-ray Spectrometer (C1XS)  Near Infrared Spectrometer (SIR-2)  Sub Kev Atom Reflecting Analyzer (SARA)  Miniature Synthetic Aperture Radar (Mini SAR)  Moon Mineralogy Mapper (M3)  Radiation Dose Monitor (RADOM) Archive Process

Sr. Steps Activity Involved No. 1. Orientatio Analyzed PDS requirement for Data by studying missions n that have archived Mars Data in PDS 2. Archive Deciding what to archive, when, and generally how. Planning Document Preparation - Archive Plan - Archive Conventions 3. Archive Learning the details of putting an archive data set Design together. EAICD Document Preparation - EAICDs for TMC and HySI 4. Software Design, Development, Testing and Operationalization of Developme CH1 PDS Data Archive Pipeline Software nt Implement and Test the data and Volume 5. Dataset Pulling the pieces together Assembly and Validation 6. Data Set PDS Data Sets quality check Review 7. Delivery Distributes Peer Reviewed data to the scientific users Data Products Definitions

Payload Type Products ISRO LEVEL-0 Raw payload data along with the ancillary information, which includes ephemeris, attitude and rates. This TMC CODMAC LEVEL 2 level of processing includes data qualification, byte alignment, data decompression and time tagging. Also the data is given along with the calibration information for radiometry. The pixel values are given in terms of counts, with a model to convert in to radiance. Data from all the three views (AFT, NADIR and FORE) are considered individually as well as together for processing.

ISRO LEVEL-1 Radiometrically calibrated/corrected and geometrically mapped products. The processing includes detector CODMAC LEVEL 3 response normalization, framing, line/pixel loss correction and tagging the selenographic coordinate to each pixel. The pixel values are given in terms of radiances, with a model to convert in to counts. Here again data from all the three views (AFT, NADIR and FORE) are considered individually as well as together for processing.

Band separated raw payload data along with the ancillary information, which includes ephemeris, attitude HySI ISRO LEVEL-0 and rates. This level of processing includes data qualification, byte alignment and time tagging. Also the data CODMAC LEVEL 2 is given along with the calibration information for radiometry. The pixel values are given in terms of counts, with a model to convert in to radiance.

ISRO LEVEL-1A Band separated radiometrically calibrated/corrected and geometrically mapped products. The processing CODMAC LEVEL 3 includes detector response normalization, framing, line/pixel loss correction and tagging the selenographic coordinate to each pixel. The pixel values are given in terms of radiances, with a model to convert in to counts

ISRO LEVEL-1B CODMAC LEVEL4 Same as Level ‘1a’. Band to band registration applied additionally in this level, which needs resampling Data Products Formats & Label Structure

Instrume Instrument PDS Primary PDS nt ID Output Data Products Secondary Data Products

TMC Three Raw Count & Browse grayscale images Radiance (BROWSE_I of Moon surface (IMAGE) MAGE) Geometry - Grid data (TABLE)

HySI Band wise images Count & Browse of Moon (64 Radiance (BROWSE_I Bands) SPECTRAL QUBE MAGE) Geometry - Grid data (TABLE) Data Products Archive Generation TMC (Level 0 Raw Data) HYSI (Level 0 Raw Data) & Ancillary Information Radiometric & Ancillary Information Correction

Band to Band Registration (For HySI)

SelenoTagger

Ch1 PDS Generator

Ch1 PDS Verifier PDS Archive Pipeline

Ch1 PDS Archival DPGS Scheduler

TMC Level 2 TMC Level 3 HYSI Level 2 HYSI Level 3 HYSI Level 4 (ISRO (ISRO Level 0) (ISRO Level 1) (ISRO Level 0) (ISRO Level 1a) Level 1b) REFDR EDR PDS RDR PDS EDR PDS RDR PDS PDS Archive Organization : Mission Level