Consider the following space missions: [Space]

I. Axiom-4

II. SpaDeX
III. Gaganyaan
How many of the space missions given above encourage and support micro-gravity research?

The correct option is All the three.

Let us analyze each of the given space missions step-by-step to understand how they encourage and support micro-gravity research:

I. Axiom-4 (Ax-4): Axiom-4 is a planned private spaceflight to the International Space Station (ISS) operated by Axiom Space. One of the core objectives of all Axiom missions is to conduct scientific experiments, technology demonstrations, and educational outreach in the unique microgravity environment of low Earth orbit (LEO). Therefore, it supports micro-gravity research.

II. SpaDeX (Space Docking Experiment): Developed by the Indian Space Research Organisation (ISRO), SpaDeX is a mission aimed at demonstrating technologies related to orbital docking, rendezvous, and formation flying. More importantly, SpaDeX serves as a key building block for developing a future space station (Bharatiya Antariksha Station) and facilitating transfer of crew or cargo. Such docking technologies are essential for long-term orbital habitats where sustained micro-gravity research is conducted. Additionally, docking experiments themselves are tested and operated under micro-gravity conditions.

III. Gaganyaan: Gaganyaan is ISRO's human spaceflight programme designed to send a crew into a low Earth orbit (LEO). During their orbital stay, the crew will conduct a variety of scientific experiments, including micro-gravity experiments in fields like biology, physics, and medicine. Thus, it directly encourages and supports micro-gravity research.

Since all three missions (Axiom-4, SpaDeX, and Gaganyaan) encourage and support micro-gravity research, the correct choice is indeed All the three.