Where the stars must not twinkle

Source– The post is based on the article “Where the stars must not twinkle” published in The Hindu on 8th October 2022.

Syllabus: GS3- Space

Relevance– India achievement in space sector

News- The article explains the logic behind establishing an astronomical observatory by the Indian government at Hanle, Ladakh. It also explains the major components of observatory and role of other stakeholders

Why has Ladakh been chosen as the location for the observatory?

Earlier the observatory was located in Bengaluru. It is known as Vainu Bapu observatory. The southwest and northeast monsoon forced the observatory for months. The rainclouds absorb starlight and radiation from cosmic objects. It prevents telescopes from capturing these objects.

To capture a cosmic phenomena like supernovae, we need radiation that lies outside the range of visible light. Therefore a dry, high-altitude place is an ideal location to capture these phenomena.

Artificial lights create light pollution. It creates obstacles for natural light. It is a contaminant for astronomy by impeding cosmic radiation. There is a relative absence of artificial lights in Hanle.

What are the major components of this observatory?

The multicoloured dish is the Major Atmospheric Cherenkov Experiment Telescope (MACE)– It is the second largest of its kind in the world and only one at such an elevation. Its goal is to detect Cherenkov radiation from space. This is a special kind of light from gamma rays,or the most energetic sources of radiation. It can result from dying stars or several galaxies.

High Altitude Gamma Ray (HAGAR)– It also looks at Cherenkov radiation, although at a lower range of energies.

Himalayan Chandra Telescope (HCT)– It is designed to detect light from the visible range

of the electromagnetic spectrum as well as from the infra-red spectrum. The second capsule, situated slightly lower than the

GROWTH-India telescope– It is equipped to track cosmic events that unfurl over time, such as afterglows of a gamma ray burst or tracking the path of asteroids

What is the negative side of the location?

The extreme weather and climate is an issue for people working there. Low atmospheric oxygen may lead to altitude sickness.

But it is widely controlled via satelink link from IIA’s Centre for Research and Education in Science and Technology, Bengaluru.

What is unique about Hanle?

Starlight is relatively unimpeded here.

Twinkling stars means starlight is being bounced back by atmospheric gases, clouds. This is relatively absent in Ladakh.

How are other stakeholders involved in this process?

Ladakh’s government is eager to expand economic opportunities via tourism and the Indian Army expanding its infrastructure development, bolster defence at the India-China border. It will create light pollution.

To strike a balance, the Ladakh government along with the IIA and India’s Scientific Ministries

is laying the groundwork to declare Hanleas an International Dark Sky Reserve by the International Dark-Sky Association.

Government is also trying to involve the local community. Eight telescopes will be set up in village clusters. Homestay owners will be trained in elementary astronomy to guide astro tourists. It will promote tourism and encourage the local people to avoid light pollution. This will be a win-win situation for all sides.