Informatics Publishing Limited

A. S. Arya ¹, S. S. Sarkar ¹, A. R. Srinivas ¹, S. Manthira Moorthi ¹, Vishnukumar D. Patel ¹, Rimjhim B. Singh ¹, R. P. Rajasekhar ¹, Sampa Roy ¹, Indranil Misra ¹, Sukamal Kr. Paul ¹, Dhrupesh Shah ², Kamlesh Patel ¹, Rajdeep K. Gambhir ¹, U. S. H. Rao ¹, Amul Patel ¹, Jalshri Desai ¹, Rahul Dev ¹, Ajay K. Prashar ¹, Hiren Rambhia ¹, Ranjan Parnami ¹, Harish Seth ¹, K. R. Murali ¹, Rishi Kaushik ¹, Deepak Patidar ¹, Nilesh Soni ¹, Prakash Chauhan ¹, D. R. M. Samudraiah ¹, A. S. Kiran Kumar ¹

Affiliations
1 Space Applications Centre, Indian Space Research Organisation, Ahmedabad 380 015, IN
2 Space Applications Centre, Indian Space Research Organisation, Ahmedabad 380 015

Abstract

Mars Colour Camera (MCC) on-board Mars Orbiter Mission is considered the ‘eye’ of the mission, taking photographs (imageries) of the surfacial features on Mars, and the cloud and dust around it. MCC is an important contextual camera for other non-imaging sensors like MSM, TIS, LAP, etc. The camera has been designed, characterized, calibrated and qualified at the Space Applications Centre, ISRO, Ahmedabad by a team of professional engineers and scientists. It has been miniaturized, ruggedized and space-qualified to match the weight and power budget of the mission. During Earth orbit phase, the images returned by the camera have been analysed qualitatively and quantitatively. The results show that MCC has been working as expected in terms of radiometry, geometry and application potential to discern various morphological features. The present article discusses these facts in detail.

Keywords

Detector, Earth imaging phase, payload, Mars colour camera.

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Arup Roy Chowdhury ¹, Manish Saxena ¹, Ankush Kumar ¹, S. R. Joshi ¹, Amitabh ¹, Aditya Dagar ¹, Manish Mittal ¹, Shweta Kirkire ¹, Jalshri Desai ¹, Dhrupesh Shah ¹, J. C. Karelia ¹, Anand Kumar ¹, Kailash Jha ¹, Prasanta Das ¹, H. V. Bhagat ¹, Jitendra Sharma ¹, D. N. Ghonia ¹, Meghal Desai ¹, Gaurav Bansal ¹, Ashutosh Gupta ¹

Affiliations
1 Space Applications Centre, Indian Space Research Organisation, Ahmedabad 380 015, IN

Abstract

Orbiter High Resolution Camera (OHRC) onboard Chandrayaan-2 Orbiter-craft, is a very high spatial resolution camera operating in visible panchromatic band. OHRC’s primary goal is to image the landingsite region prior to landing for characterization and finding hazard-free zones. Post landing operation of the OHRC will be for scientific studies of small-scale features on the lunar surface. OHRC makes use of the time delay integration detector to have good signal-tonoise ratio under low illumination condition and less integration time due to very high spatial resolution. Ground sampling distance (GSD) and swath of OHRC (in nadir view) are 0.25 m and 3 km respectively, from 100 km altitude. GSD is better than 0.32 m in oblique view (25° pitch angle) during landing site imaging from 100 km altitude in two stereo views in consecutive orbits. This article includes the details of the configuration, sub-systems, imaging modes, and optical, spectral and radiometric characterization performance.

Keywords

Ground Sampling Distance, Orbiter High Resolution Camera, Relative Spectral Response, Square Wave Response, Time Delay Integration.

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Arup Roy Chowdhury ¹, Vishnukumar D. Patel ¹, S. R. Joshi ¹, A. S. Arya ¹, Ankush Kumar ¹, Sukamal Paul ¹, Dhrupesh Shah ¹, Pradeep Soni ¹, J. C. Karelia ¹, Minal Sampat ¹, Satish Sharma ¹, Sandip Somani ¹, H. V. Bhagat ¹, Jitendra Sharma ¹, Amitabh ¹, K. Suresh ¹, R. P. Rajasekhar ¹, B. B. Bokarwadia ¹, Mukesh Kumar ¹, D. N. Ghonia ¹

Affiliations
1 Space Applications Centre, Indian Space Research Organisation, Ahmedabad 380 015, IN

Abstract

The paper presents the design and development of Terrain Mapping Camera-2 (TMC-2) for Chandrayaan- 2 including science objectives; system and sub-system configuration along with the realized performance of the camera; payload characterization; aspects related to data products, etc. TMC-2, onboard Chandrayaan-2 orbiter-craft is a follow-on of the Terrain Mapping Camera (TMC) onboard Chandrayaan- 1. It operates in visible panchromatic band. It comprises three identical electro-optical chains aligned for three views (–25, 0 and +25 degree) along track direction for generation of stereo images. It provides data with 5 m horizontal ground sampling distance to generate digital elevation model. TMC-2 based on the new configuration and sub-system designs has reduction in mass and power by more than 40% compared to TMC, without compromising the performance.

Keywords

Digital Elevation Model, Light Transfer Characteristics, Relative Spectral Response, Signal-to-noise Ratio, Stereo Imaging, Square Wave Response, Terrain Mapping Camera-2.

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