SHAPE -- A Spectro-Polarimeter Onboard Propulsion Module of Chandrayaan-3 Mission

Anuj Nandi; Swapnil Singh; Bhavesh Jaiswal; Anand Jain; Smrati Verma; Reenu Palawat; Ravishankar B. T.; Brajpal Singh; Anurag Tyagi; Priyanka Das; Supratik Bose; Supriya Verma; Waghmare Rahul Gautam; Yogesh Prasad K. R.; Bijoy Raha; Bhavesh Mendhekar; Sathyanaryana Raju K.; Srinivasa Rao Kondapi V.; Sumit Kumar; Mukund Kumar Thakur; Vinti Bhatia; Nidhi Sharma; Govinda Rao Yenni; Neeraj Kumar Satya; Venkata Raghavendra; Vivechana M. S.; Evangelin Leeja Justin; Praloy Karmakar; Anurag Patra; Naga Manjusha J.; Motamarri Srikanth; Chinmay Kumar Rajhans; Kalpana K.; Veeramuthuvel P

arXiv · 2412.07416

SHAPE -- A Spectro-Polarimeter Onboard Propulsion Module of Chandrayaan-3 Mission

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Abstract

SHAPE (Spectro-polarimetry of HAbitable Planet Earth) is an experiment onboard the Chandrayaan-3 Mission, designed to study the spectro-polarimetric signatures of the habitable planet Earth in the near-infrared (NIR) wavelength range (1.0 - 1.7 $\mu$m). The spectro-polarimeter is the only scientific payload (experimental in nature) on the Propulsion Module (PM) of the Chandrayaan-3 mission. The instrument is a compact and lightweight spectro-polarimeter with an Acousto-Optic Tunable Filter (AOTF) at its core. The AOTF operates in the frequency range of 80 MHz to 135 MHz with a power of 0.5 - 2.0 Watts. The two output beams (e-beam and o-beam) from the AOTF are focused onto two InGaAs detectors (pixelated, 1D linear array) with the help of focusing optics. The primary (aperture) optics, with a diameter of $\sim$2 mm, collects the NIR light for input to the AOTF, defining the field of view (FOV) of 2.6$^\circ$. The payload has a mass of 4.8 kg and operates at a power of 25 Watts. This manuscript highlights some of the ground-based results, including the post-launch initial performance of the payload while orbiting around the Moon to observe Earth.

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Anuj Nandi, Swapnil Singh, Bhavesh Jaiswal, Anand Jain, Smrati Verma, Reenu Palawat, Ravishankar B. T., Brajpal Singh, Anurag Tyagi, Priyanka Das, Supratik Bose, Supriya Verma, Waghmare Rahul Gautam, Yogesh Prasad K. R., Bijoy Raha, Bhavesh Mendhekar, Sathyanaryana Raju K., Srinivasa Rao Kondapi V., Sumit Kumar, Mukund Kumar Thakur, Vinti Bhatia, Nidhi Sharma, Govinda Rao Yenni, Neeraj Kumar Satya, Venkata Raghavendra, Vivechana M. S., Evangelin Leeja Justin, Praloy Karmakar, Anurag Patra, Naga Manjusha J., Motamarri Srikanth, Chinmay Kumar Rajhans, Kalpana K., Veeramuthuvel P. 2024-12-10. SHAPE -- A Spectro-Polarimeter Onboard Propulsion Module of Chandrayaan-3 Mission. https://arxiv.org/abs/2412.07416

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