ISRO’s Historic SpaDeX Mission

The Indian Space Research Organisation (ISRO) achieved a major milestone by successfully docking two of its SpaDeX satellites in space. This makes India the fourth country in the world to possess the technology for rendezvous, docking, and undocking spacecraft in orbit.

Key Details:

• Mission Overview: The SpaDeX mission involved two satellites: SDX01 (the Chaser) and SDX02 (the Target), each weighing about 220 kg. These satellites were launched together on December 30, 2024, aboard the PSLV C60 rocket from the Satish Dhawan Space Centre in Sriharikota, India.
• Docking Process: After launch, the satellites were placed in a 475 km orbit above Earth. Over several days, they gradually moved closer to each other, first from a distance of 1.5 km, and then to just 3 meters apart. Once this was achieved, the docking maneuver began, and the two satellites were successfully docked.
• Steps Taken:
  • Chaser satellite moved from a distance of 15 meters to 3 meters from the Target.
  • The satellites were carefully aligned and docked.
  • After docking, a retraction process secured the connection, followed by rigidization to stabilize the docking.

What is Space Docking?

Space docking is the process of bringing two spacecraft together in orbit and physically linking them. This technology is essential for many advanced space missions, including:

• Human spaceflight: Docking is necessary for missions that send humans to the Moon and bring lunar samples back to Earth.
• Space stations: It’s crucial for building and operating space stations, like the Bharatiya Antariksh Station (India's planned space station).
• Satellite servicing: Spacecraft can dock to perform maintenance or refueling on other satellites.

The SpaDeX Mission

• The SpaDeX mission is a significant step for ISRO as it demonstrates India’s capability in orbital docking. With this success, India joins the ranks of space giants like China, Russia, and the United States, who have already achieved docking technology. The mission also supports cost-effective satellite operations and reduces the need for multiple rocket launches to achieve shared space goals.
• Key Details of the SpaDeX Mission:
  • Primary Payloads: The mission features two spacecraft: SDX01 (Chaser) and SDX02 (Target), which were launched into an orbit 5 km apart.
  • Mission Process: Over 10-14 days, ISRO scientists gradually brought the two spacecraft closer to each other, with the final docking occurring at an altitude of 470 km above Earth.
  • Payloads on the Spacecraft:
    • SDX01 (Chaser) carries a High-Resolution Camera.
    • SDX02 (Target) includes a Miniature Multispectral Payload and a Radiation Monitor Payload. These instruments are designed to capture high-resolution images and monitor natural resources and vegetation on Earth.
  • Launch Vehicle: The mission was launched using the PSLV-C60 rocket, which also carried 24 secondary payloads in addition to the two primary spacecraft.