29th September 2025

Explanation – Gaia is indeed an ESA mission designed to create the largest, most precise three-dimensional map of the Milky Way galaxy, making statement 1 correct. Launched in 2013, Gaia operates from Lagrange Point 2, approximately 1.5 million km from Earth, shielded from the Sun's glare and Earth's atmospheric effects, making statement 2 correct. While Gaia can detect Near-Earth Objects and map Solar System objects, statement 3 is correct in principle but the question asks for precision. However, Gaia aims to map about one billion stars (not 10 billion), making statement 4 incorrect. 

Explanation – The Dugong or "sea cow" is indeed the only herbivorous mammal that is strictly marine and the only extant species in the family Dugongidae, making statement 1 correct. However, Dugongs are distributed in shallow tropical waters in the Indo-Pacific region (not subtropical and temperate waters), making statement 2 incorrect. The IUCN status of Dugong is Vulnerable, making statement 3 correct. In India, they are found in the Gulf of Kutch, Gulf of Mannar, Palk Bay, and Andaman & Nicobar Islands, where they are the state animal of Andaman & Nicobar Islands. 

Explanation – The Hanle Dark Sky Reserve, notified in December 2022, is India's first International Dark Sky Reserve and is located within the Changthang Wildlife Sanctuary, making statement 1 correct. While the Indian Institute of Astrophysics (IIA) manages the Indian Astronomical Observatory at Hanle, the primary funding for socio-economic initiatives is provided by the UT Ladakh administration, not IIA, making statement 2 incorrect. The project indeed aims to promote astro-tourism for local livelihood generation while curtailing light pollution, making statement 3 correct. 

Explanation – The Cheros were indeed concentrated in Palamu (Jharkhand), Shahabad (Bihar), and parts of eastern Uttar Pradesh, making statement 1 correct. However, Medini Rai's resistance against the Mughals occurred during Emperor Aurangzeb's reign (not Akbar's), when Palamu forts were fortified and challenged Mughal armies, making statement 2 incorrect. During the British colonial period, the Cheros were known for their skilled archery and guerrilla warfare tactics in the rugged terrain, joining other tribal communities in rebellions against British policies, making statement 3 correct. 

Explanation – The UN General Assembly consists of all 193 UN member states, but non-member states like the Holy See and Palestine can participate as permanent observers, making statement 1 incorrect. Important questions such as recommendations on international peace and security, admission of members, and budgetary matters require a two-thirds majority of members present and voting, making statement 2 correct. However, most UNGA resolutions are non-binding and serve as politically influential instruments—binding enforcement is typically the Security Council's domain, making statement 3 incorrect.