Light Pollution Is Erasing India's Night Sky, And 800 Million People Are Losing More Than Stars

Sixty years ago, a power cut in any Indian city was an inconvenience that came with one accidental gift: the stars came back. People stepped outside and looked up, and the Milky Way was a white smear across the whole width of the sky, not a rumour. That sky is now structurally gone for most Indians. A 2016 global atlas of artificial sky brightness, published in Science Advances by Fabio Falchi and colleagues, found that more than 98 percent of the Indian population lives under light-polluted skies. For the roughly 800 million people concentrated in and around India's cities and towns, the Milky Way is invisible. Not obscured by cloud. Invisible by design, every night, permanently.
The numbers are specific enough to be uncomfortable. The naked-eye star count from a truly dark sky runs to about 4,500 stars on a clear night. From the centre of Mumbai or Delhi, that number drops to fewer than a dozen. The sky people are seeing is not a dimmer version of the real sky. It is a different sky entirely, an orange-grey ceiling with a few bright planets punching through.
The Nakshatra system, the 27 lunar mansions that form the backbone of Vedic astrology and the Hindu calendar, was built by people who could see every star in it. Krittika, Rohini, Ardra, Pushya: these were not abstractions. They were fixed points a farmer could locate before dawn to know when to sow, a bride's family could consult to set a wedding date, a sailor could use to hold a course across the Arabian Sea. The system assumed a sky you could actually read. That assumption no longer holds for the majority of Indians who would need to use it.
Chanda Mama, the moon uncle of every Indian lullaby, survives light pollution because the moon is bright enough to cut through urban glow. But the stories that surrounded the moon, the ones that required you to trace a line from Chandra across to a specific Nakshatra to understand what the month meant, those require a sky most Indians no longer have. The mythology did not exist separately from the visible sky. The visible sky was the text.

India's astronomy tradition is among the oldest documented on earth. Aryabhata, working in the 5th century, calculated the Earth's rotation and the length of the solar year with an accuracy that would not be matched in Europe for a thousand years. He did this with naked-eye observation. The instruments of classical Indian astronomy, the Jantar Mantar observatories built by Maharaja Jai Singh II in Delhi, Jaipur, Ujjain, Mathura, and Varanasi in the early 18th century, were calibrated for skies that no longer exist at those locations. The Samrat Yantra in Jaipur, the largest sundial in the world, was built to track celestial positions visible to the unaided eye. The sky it was designed to read has been replaced by a sodium-vapour haze.
ISRO's missions, Chandrayaan-3 landing near the lunar south pole in 2023, Aditya-L1 reaching its halo orbit around the Sun-Earth Lagrange point, represent India's continued engagement with space science at the highest level. But there is a distance between a nation sending instruments to the Moon and a nation whose children have never seen the Moon's companion stars with their own eyes. Professional astronomy and naked-eye wonder are not the same thing, and only one of them is being lost.

The loss is not only cultural. Artificial light at night suppresses melatonin production, this is established biology, not contested. A 2019 study published in JAMA Internal Medicine, tracking over 40,000 women, found that sleeping with artificial light on was associated with a 17 percent higher risk of weight gain and a measurable increase in cardiovascular risk markers. India's cities are among the fastest-growing sources of artificial light on earth, and the exposure is not limited to the hours of sleep. The sky above an Indian metro now glows all night at intensities the human body never evolved to tolerate.
Darkness, actual darkness, is a resource. It regulates circadian rhythm, it is the condition under which the body repairs itself, and it is the perceptual state in which the sky becomes available. When darkness is gone, all three go with it.

Dark sky preserves exist. Spiti Valley in Himachal Pradesh is one of the few places in India where the Milky Way is still reliably visible to the naked eye, the altitude, the cold, and the distance from major urban centres have kept the sky relatively intact. Hanle in Ladakh, home to the Indian Astronomical Observatory, sits at 4,500 metres and offers some of the darkest skies in Asia. The Indian Institute of Astrophysics operates there precisely because the darkness is the asset.
But Spiti and Hanle are not accessible to 800 million people. They are destinations requiring planning, money, and days of travel. The sky that used to be available from a rooftop in Pune or a field outside Lucknow, that sky required nothing. It was simply there, every night, for anyone who looked up. The loss is not that Indians cannot access dark skies. The loss is that the sky stopped being a commons.
The Nakshatras were mapped, the lullabies were written, and Aryabhata did his calculations in a world where the night sky was not a privilege. Every generation since has inherited a slightly dimmer version of that sky, and the inheritance has thinned to the point where most Indians alive today have never seen what their grandparents took for granted on any clear night. The science, the mythology, and the body's own need for darkness all pointed at the same ceiling, and the ceiling has been replaced with light.