Axiom-4 Mission to the International Space Station (ISS) 

Syllabus :GS3/Space 

In News

• The launch of the Axiom-4 mission has been postponed again due to a technical issue with SpaceX’s Falcon 9 rocket. 

The Axiom-4 (Ax-4) mission 

• It will spend 14 to 21 days on the ISS, conducting over 60 experiments in collaboration with 31 countries, covering fields like biomedical research, Earth observation, and materials science. 
• Some experiments involve ISRO, offering India key insights for its upcoming Gaganyaan mission, now expected in 2027. 
• The Ax-4 crew includes members from India, Poland, and Hungary, marking each nation’s first mission to the space station in history and second government-sponsored human spaceflight mission in over 40 years.
  • Shubhanshu Shukla will be India’s second national astronaut to go to space since 1984.
• The mission highlights Axiom Space’s role in advancing international access to low-Earth orbit.

Axiom’s Journey to ISS

• To reach the ISS, the mission must launch within a carefully calculated window that aligns the spacecraft’s trajectory with the ISS’s orbit. 
• After liftoff, Falcon 9’s first stage separates and returns to Earth, while the second stage continues the ascent before releasing the Dragon capsule into orbit.
• The ISS, located about 400 km above Earth and moving at 28,000 kmph, requires the Dragon to gradually raise its orbit and adjust its path using 16 Draco thrusters via a series of phasing maneuvers. 
• Unlike Russia’s faster Soyuz craft, Dragon typically takes about 28 hours to reach the ISS due to its newer design and the need to conduct in-flight tests. 
• As it nears the station, Dragon performs a final maneuver, enters the 200-meter “keep-out sphere,” and uses GPS, cameras, and Lidar for autonomous docking.
  • Once docked, safety checks are completed over 1–2 hours before the astronauts can board the ISS.

Source :IE