The Indian astronaut Group Captain Shubhanshu Shukla, as part of the Ax-4 mission, is traveling towards the International Space Station (ISS) aboard the SpaceX Dragon capsule. This capsule is set to dock 40-45 minutes ahead of its scheduled time. The Dragon capsule is currently about 200-400 meters away from the ISS, having entered the close approach zone.
This spacecraft orbits the Earth at a velocity of 28,000 km/hour, at an altitude of 418 km. Since the launch, it has completed roughly 26 hours of travel and is now in its final stages. The spacecraft performed various orbital maneuvers to align with the ISS’s orbit.
Source: aajtak
Dragon Capsule Docking Procedure
The docking of the Dragon capsule with the ISS is an autonomous process, although Shubhanshu and Commander Peggy Whitson will be monitoring it closely. This procedure is meticulously designed for precision and safety, unfolding in four main stages...
Rendezvous:
After launch, the Dragon capsule adjusts its speed and direction with a 90-second engine firing. By 2:33 PM IST, the spacecraft, starting 400 meters below and 7 km behind, is now merely 200 meters away. SpaceX and NASA ground controllers constantly inspect the spacecraft systems.
Close Approach:
At 200 meters, Dragon begins direct communication with the ISS. This phase can last up to 6 hours, ensuring a safe path with no risk involved.
The
docking can be watched here.
Final Approach:
At 20 meters, Dragon uses laser sensors, cameras, and GPS to achieve precise alignment with the ISS’s Harmony module docking port. It advances at a speed of a few centimeters per second, under highly controlled, slow motion. During this time, Shubhanshu will monitor the spacecraft's speed, orbit, and systems like avionics and propulsion.
Soft and Hard Capture
Soft Capture:
The magnetic grippers draw the spacecraft towards the docking port.
Hard Capture:
Mechanical latches and hooks secure the spacecraft, creating a pressure-tight seal.
Following this, a 1-2 hour inspection will ensure air leakage and pressure stability. Thereafter, the crew will begin entering the ISS.
