ISRO's Mission for Cosmic X-ray Polarisation Study

The question asks to identify the specific mission launched by the Indian Space Research Organisation (ISRO) in January 2024, which is designed to study the polarisation of cosmic X-rays. Let's examine the options:

Understanding the XPoSat Mission

ISRO successfully launched the XPoSat (X-ray Polarimeter Satellite) mission in January 2024. This groundbreaking mission is dedicated to the field of X-ray astronomy. Its primary scientific objective is to measure the polarisation of X-rays originating from celestial sources. Studying the polarisation of these cosmic X-rays provides crucial information about the physics governing extreme environments in the universe, such as those found in neutron stars and black holes.

Analyzing Other ISRO Missions

To confirm XPoSat as the correct answer, let's look at the other options provided:

• Aditya-L1: This ISRO mission, launched in September 2023, is focused on studying the Sun (solar corona and atmospheric dynamics). It is not designed for studying cosmic X-ray polarisation.
• RISAT-1: RISAT-1 is an Indian radar imaging satellite launched earlier. Its purpose is Earth observation using C-band microwave imagery, primarily for applications like agriculture and disaster management, not X-ray astronomy.
• AstroSat: AstroSat is ISRO's first dedicated astronomy observatory in space, launched in 2015. It observes celestial objects in ultraviolet, visible, and X-ray parts of the electromagnetic spectrum. While AstroSat studies X-rays, the XPoSat mission is specifically designed for the unique task of measuring X-ray polarisation and was launched in January 2024.

Based on the launch date and specific scientific objective mentioned in the question (studying the polarisation of cosmic X-rays), XPoSat is the correct identification for ISRO's January 2024 mission.