Science and Technology › Space

Astronomy and cosmology

Astronomy and cosmology: telescopes and observatories, stars, black holes and neutron stars, exoplanets, dark matter and dark energy, the Sun's cycle and space weather, eclipses, comets and asteroids. Prelims has asked about Cepheids, nebulae and pulsars, and about solar flares.

UPSC has asked

Prelims 2025: solar flares and coronal mass ejections striking the outer atmosphere
Prelims 2023: Cepheids, nebulae and pulsars
Prelims 2022: effects of a major solar storm on the Earth

Showing 1 of 5 subjects, those that changed from 16 to 31 July 2026.Show all

Indian Astronomical Observatory, Hanle

Prelims

The Indian Astronomical Observatory at Hanle in Ladakh, at 4,517 metres, is run remotely from Bengaluru by the Indian Institute of Astrophysics and gives more than 250 usable nights a year with very little water vapour.

What changed

29 Jul 2026New subject
- The 2 metre Himalayan Chandra Telescope at Hanle in Ladakh, sited at 4,517 metres and run remotely from Bengaluru since 2001, has completed 25 years. The site gives more than 250 usable nights a year with very little water vapour.
- The budget has announced a 3.7 metre upgraded telescope and a 13.7 metre National Large Optical Infrared Telescope, both at Hanle.
PIB, 29 Jul 2026: Celebrating 25 years of the Himalayan Chandra Telescope in Hanle (opens in a new tab)

Also filed elsewhere

Space weather forecasting from Aditya-L1 · on Moon, Sun and planetary missions
A solar flare gives no useful warning once it has erupted, because its radiation crosses to Earth in about eight minutes.
The Hanle Dark Sky Reserve · on Chemicals, noise, light and soil pollution
Ladakh's administration notified the Hanle Dark Sky Reserve (HDSR) in December 2022, India's first and still its only one.