SpaDeX

Context

ISRO to conduct Space Docking Experiment

About ISRO’s Space Docking Experiment (SpaDeX)

• Purpose: Demonstrate India’s first space docking capability, essential for future missions like lunar sample return, space station assembly, and human spaceflight to the Moon.
• Launch Vehicle: PSLV C60 from Sriharikota.
• Satellites: Two small satellites, SDX01 (Chaser) and SDX02 (Target).

Space Docking

• Definition: Process of maneuvering two spacecraft into the same orbit and joining them.
• Importance:
  • Essential for modular space systems like the  International Space Station (ISS) .
  • Key for India’s Bharatiya Antarisksha Station (target by 2035).
  • Required for future   Chandrayaan-4 mission or sample return and other complex missions.
• Launch:
  • Satellites SDX01 and SDX02 injected into a 470-km circular orbit.
• Separation:
  • Satellites initially drift 10-20 km apart due to relative velocity.
• Target Satellite Adjustment:
  • SDX02 propulsion system halts further drift by matching velocity with SDX01.
• Docking:
  • SDX01 (Chaser) reduces distance to SDX02 step-by-step: 5 km → 1.5 km → 500 m → 225 m → 15 m → 3 m → Docking.
  • Monitoring: A video camera tilt mechanism observes docking.
  • Post-docking: Satellites transfer electrical power.
• Undocking:
  • Satellites undock and move to separate orbits to perform experiments over the next two years.

PSLV C60 Innovations

• New Assembly Method:
  • PSLV built in a new integration facility and transported to the pad, reducing mission preparation time.
• Biological Experiment:
  • First time ISRO includes a biological experiment.
• Experiments:
  • POEM (PS4 Orbital Experiment Module) for testing 24 technologies.

Payload Experiments

• Biological Studies:
  • CROPS (Compact Research Module for Orbital Plant Studies): Germination and sustenance of a plant up to a two-leaf stage.
  • Amity University: Plant cell study in microgravity.
  • RV College of Engineering: Study on growth curve of gut bacteria in space.
• Technological Innovations:
  • Debris Capture Robotic Arm: Visual feed and motion prediction to capture debris.
  • Satellite Servicing Arm: For potential in-orbit satellite repairs.

Future Applications

• Space Station Assembly:
  • Docking technology critical for assembling India’s space station by 2035.
• Lunar Sample Return:
  • Used in Chandrayaan-4 for sample return missions.
• Human Spaceflight:
  • Preparatory step for future crewed missions to the Moon.

Source: IE

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Previous Year Question

Which of the following pair(s) is/are correctly matched?
Spacecraft: Purpose
1. Cassini-Huygens: Orbiting the Venus and transmitting data to the Earth
2. Messenger: Mapping and investigating the Mercury
3. Voyager 1 & 2: Exploring the outer solar system
Select the correct answer using the codes given below.

[UPSC Civil Services Exam – 2014 Prelims]

(a) 1 only
(b) 2 and 3 only
(c) 1 and 3 only
(d) 1, 2 and 3

Answer: (b)

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