Environment › Pollution
Chemicals, noise, light and soil pollution
Pollution that is not air, water or waste: hazardous chemicals and the conventions that govern them, pesticides, the ozone layer, noise, light and contaminated soil. Environmental pollution is part of the GS3 syllabus.
15 Sep 2026 · Prelims
The Hanle Dark Sky Reserve
Ladakh's administration notified the Hanle Dark Sky Reserve (HDSR) in December 2022, India's first and still its only one. It held its fourth star party in September 2026, drawing astronomy enthusiasts from across India.
- It lies inside the Changthang Cold Desert Wildlife Sanctuary.
- The Indian Institute of Astrophysics (IIA), under the Department of Science and Technology (DST), runs the observatory there.
- No Indian law creates the designation, so the notification is the Union Territory's own.
- Abroad the status is certified by DarkSky International, once the International Dark-Sky Association.