Astronomy, the most ancient of sciences, offers a boundless, free resource: the night sky. For those living far from urban glow, this celestial canvas ignites passion, sparks imagination, and can even forge livelihoods. This is the inspiring tale of Hanle, a remote Himalayan village now renowned for boasting some of the planet’s darkest skies. With a rare Bortle-1 clarity rating, indicating virtually no light pollution, Hanle truly proclaims that the wonders of astronomy are accessible to all.
Perched in the majestic region of Ladakh, Hanle proudly stands as India’s inaugural dark sky reserve. Its preservation is a collaborative effort, guided by an agreement involving the Indian Institute of Astrophysics (IIA) in Bengaluru, the Union Territory of Ladakh, and the Ladakh Hill Development Council in Leh. From its roots as a home for nomadic communities, Hanle is gracefully evolving into a premier destination for celestial observation.
A dark sky reserve is a specially designated zone recognized for its exceptionally pristine night skies, meticulously maintained by actively minimizing artificial light pollution. Hanle’s Dark Sky Reserve exemplifies a distinctive, government-supported and scientific initiative focused on sustainable development. It lies nestled within the Changthang Wildlife Sanctuary, encircling the prominent Indian Astronomical Observatory, a vital research hub overseen by the IIA.
This observatory houses an impressive array of instruments: two optical telescopes – the Himalayan Chandra Telescope and the GROWTH India Telescope (a collaboration with IIT Bombay) – alongside two Cherenkov telescopes, including the High Altitude Gamma-Ray Telescope Array (in partnership with the Tata Institute of Fundamental Research) and the Major Atmospheric Cherenkov Experiment (with the Bhabha Atomic Research Centre).
Dorje Angchuk, the Observatory’s engineer-in-charge, highlights Hanle’s unparalleled advantages for astronomical research: “Countless clear sky nights, minimal atmospheric particles to absorb celestial light, and exceptionally low light pollution collectively establish Hanle as an unrivaled location for observing the cosmos.”
To fiercely combat light pollution, the IIA has proactively supplied the village with lamp shades, blackout curtains, and warm-toned light bulbs for all residences and facilities, as explained by Mr. Angchuk. Furthermore, to bolster astrotourism, IIA scientists have meticulously trained 25 local young individuals, including 18 women, to become “Astronomy Ambassadors.” These Ambassadors are provided with telescopes and educated in fundamental astronomy, enabling them to lead captivating night-sky tours for visitors and earn supplementary income.
Image: Enthusiastic participants of the Hanle Star Party gather at the Himalayan Chandra Telescope.
A Celestial Gathering: The Hanle Star Party
Since 2023, the Hanle Dark Sky Reserve has been the proud host of an annual “star party.” The most recent, third edition, ran from September 18 to September 23 this year. These unique gatherings bring together astronomy enthusiasts, astrophotographers, and casual stargazers alike to collectively observe and celebrate the awe-inspiring night sky. They foster a vibrant environment for education, practical learning, and collaborative exploration of the cosmos.
Far from a typical gathering, a star party unfolds beneath pristine dark skies, deliberately free of white light and loud noises. Participants engage in hushed observations, completely immersed in the celestial display above.
This year’s event drew around 47 participants, ranging from amateur enthusiasts to seasoned professional stargazers (including the author). Early evenings were dedicated to insightful tutorials and lectures on maximizing the pristine dark skies, followed by nights spent observing and capturing breathtaking images of the heavens. The organizing team received invaluable support from volunteers of the Bangalore Astronomical Society and dedicated returning attendees.
“Hanle’s skies are exceptionally pristine, allowing for observations of numerous elusive and unique phenomena simply not visible elsewhere,” remarks Ajay Talwar, an amateur astronomer and telescope manufacturer who operates Aperture Telescope in Gurugram.
Among these rare sights is the zodiacal light – a subtle glow visible during twilight, tracing the Sun’s path across the sky. This phenomenon, caused by sunlight scattering off dust in the inner Solar System, is, according to Talwar, “a spectacle uniquely observable from Hanle.”
A seasoned astrophotographer since 1987, Mr. Talwar led an orientation during the star party, educating attendees on various astronomical phenomena and optimal viewing times. He introduced the gegenschein, a luminous patch appearing opposite the Sun’s position (the antisolar point), and the captivating Belt of Venus – a soft pink band of light seen in the evening sky, sitting just above Earth’s dark blue shadow, both resulting from scattered sunlight.
“The combination of clear, dry skies and the invaluable time I get to spend observing the heavens draws me back here annually,” shared Neelam Talwar, an Air India crew member and an active participant of the Amateur Astronomers Association of New Delhi, during the event.
Ms. Talwar particularly enjoys photographing the Belt of Venus and the zodiacal light. She recounted highlights from previous events, including how participants mastered the art of astrophotography by skillfully lighting human subjects against a dramatic, star-filled backdrop.
While Hanle’s low oxygen, low humidity, and high ultraviolet radiation create ideal conditions for astronomical observations, Mr. Talwar cautions that these factors are intensely demanding on the human body. He strongly advises visitors to arrive with meticulous planning and sufficient time for acclimatization.
The IIA, indeed, mandated that all star party attendees spend two days in Leh prior to traveling to Hanle, allowing for crucial acclimatization to the thin air and dry conditions. A medical expert outlined potential high-altitude health risks, and mandatory medical check-ups were conducted before the journey. Even at Hanle, situated at a formidable 4,250 meters above sea level, nightly medical evaluations and dedicated volunteers ensured the well-being of all participants.
Participation in the star party is determined through an application process, with forms typically released by the IIA around August. Selections are made based on an applicant’s astronomical experience, genuine passion for the subject, and their proposed plans for making the most of Hanle’s unparalleled skies.
Community, Culture, and the Cosmos
Rangdol Dorje, an Astronomy Ambassador since 2022, attests to the positive economic impact of astrotourism, noting a significant boost in the local economy driven by visitors flocking to Hanle for stargazing. Mr. Angchuk confirmed this trend, reporting approximately 10,000 visitors to the reserve in 2024 alone.
Mr. Dorje shares that tourists frequently inquire about night sky visibility upon entering the village, often expressing keen interest in observing planets and the moon through telescopes. Despite his background in computer science, Mr. Dorje found astronomical concepts readily understandable, emphasizing his belief that “astronomy is for everyone.”
“To be born in Hanle is a true blessing,” remarked Tsering Skitzom, a new Astronomy Ambassador with an accounting background. She underscored the importance of sharing Hanle’s unique natural environment and astronomical wonders with outsiders. “Practical experience outweighs theory,” Ms. Skitzom added, explaining that their learning happens directly through telescopes, guided by seasoned ambassadors.
During the colder winter months, when tourist numbers dwindle, the Astronomy Ambassadors shift their focus to educating local schoolchildren, tutoring them in astronomy.
Padma Ishey, another Astronomy Ambassador, explained his unique pedagogical approach: “I teach alternative learning courses that blend astronomy with local culture.” He clarified that this “alternative approach” covers subjects typically absent from school curricula, believing that a strong cultural foundation empowers young students to conduct more impactful research.
In a significant cultural preservation effort, Mr. Ishey, alongside educator and filmmaker Anmol Tikoo, has been diligently gathering traditional night-sky knowledge. They collect stories, proverbs, and folk songs from elders in Hanle and neighboring communities, a presentation that many star party participants found profoundly insightful.
Image: A scenic view of Hanle village, with the majestic Indus River flowing through Changthang.
Beyond the Mountains: A Journey of Discovery
Namratha Pathak, a scientist from the Department of Science and Technology, Government of India, passionately emphasized the crucial interlinkage between science, nature, indigenous knowledge, and local habitats, advocating for their integrated conservation. She described her star party experience as “spectacular” and “breathtaking,” particularly cherishing her unforgettable glimpse of the Milky Way.
Khursheed Alam, a senior lecturer from Jammu and Kashmir, expressed his intention to share his newfound knowledge with his students. “I learned about various types of telescopes, especially automated models,” he stated, adding, “one of the most fascinating skills I acquired was how to take astrophotographs using just my phone.”
Rashmi Sheoran, an astronomy educator from Haryana attending her first star party, admitted she previously thought online images of the universe surpassed views through a telescope. Her experience at Hanle, however, shifted her perspective: “After observing the planets with my own eyes, I realized the view was as stunning, if not more so, than any photograph I had seen,” she happily noted.
Muneer Wani, a teacher and STEM/Akaash labs nodal officer for Jammu & Kashmir, advocates for individuals interested in space science and astronomy to pursue diverse careers beyond conventional engineering and medicine. He proudly shared how, with Mr. Talwar’s guidance at the party, he significantly enhanced his astrophotography skills, successfully capturing high-quality images of both the Milky Way and the Andromeda galaxy.
On the final evening of the party, participants warmly welcomed both tourists and local residents for a collective sky exploration through telescopes. This public event attracted nearly 300 individuals, including Indian Army soldiers and nearby stationed officers, all united by the wonders of the cosmos.
To further enhance astrotourism, Mr. Angchuk announced plans for a new mini-planetarium within the reserve. Additionally, a transparent “Astroglobe” dome is envisioned to provide an unparalleled stargazing experience for visitors even during the challenging winter months.
Embodying its captivating motto, “come for the mountains, stay for the stars,” the Hanle Dark Sky Reserve stands as a beacon of preservation. It meticulously safeguards the pristine Himalayan night skies for generations to come, all while catalyzing sustainable economic growth and enriching the lives of the local community.