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SpaDeX Mission

Subject: Science and Technology

Relevance: Space missions are crucial for the UPSC syllabus, having been a topic of both Prelims and Mains questions. Recent advancements in India's space capabilities, such as the successful docking of a satellite by ISRO, underscore the significance of this topic.

Why in the News?

The Indian Space Research Organisation (ISRO) successfully completed the docking process of the SpaDeX (Space Docking Experiment) satellites on January 16, making India the fourth country, after the US, Russia, and China, to achieve this milestone. The experiment was postponed from January 7 due to an abort scenario, leading to further simulations to enhance accuracy.

Key Takeaways

• SpaDeX mission launched on December 30 by PSLV-C60 from Satish Dhawan Space Centre, Sriharikota, placing two satellites in lower earth orbit (below 2000 km).
• Two satellites, SDX01 Chaser and SDX02 Target, demonstrated successful docking after reducing separation from 20 km to 3 m.
• Chaser satellite equipped with a high-resolution camera; Target satellite carries a multispectral payload and radiation monitor.
• The launch vehicle's fourth stage carried the POEM (PS4 Orbital Experiment Module) with 24 technologies, including the CROPS for cultivating plant life in microgravity.
• The Vikram Sarabhai Space Centre developed an experiment to grow cowpea seeds in space, with three seedlings sprouting leaves.

Important Payloads

• Relocatable Robotic Manipulator-Technology Demonstrator (RRM-TD): India's first space robotic manipulator with walking capability.
• Debris Capture Robotic Manipulator: Demonstrates capturing of tethered debris using visual serving and object motion prediction.
• Amity Plant Experimental Module in Space (APEMS): Studies plant callus in microgravity using the 'Spinacia oleracea' model.

Bharatiya Docking System

• Docking involves bringing two fast-moving spacecraft together in the same orbit to perform missions requiring large spacecraft assemblies.
• India's system uses an androgynous mechanism similar to the International Docking System Standard (IDSS) but with fewer motors (2 compared to 24).
• The mission utilized new sensors (e.g., Laser Range Finder) for precise measurement during docking.
• Docking technology is crucial for the Bharatiya Antariksh Station, planned for launch in 2028, and Chandrayaan-4 lunar mission.

First Docking in Space

NASA's Gemini VIII in 1966 was the first spacecraft to dock with a target vehicle, commanded by Neil Armstrong.

BEYOND THE NUGGET: Third Launch Pad at Sriharikota

• The Union Cabinet approved a third launch pad at Sriharikota to accommodate the Next Generation Launch Vehicle (NGLV) and support future missions.
• The third launch pad will be ready in four years, costing Rs 3,984.86 crore, and will support satellite preparation and vehicle assembly.
• Currently, Sriharikota has two launch pads for smaller and heavier vehicle launches.

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