Kodaikanal Solar Observatory: 125 years of gazing at the brightest star in the earth’s sky

It’s 9 am on a bright, sunny morning in Kodaikanal. P Manikandan, or Sathish, as he is known to colleagues and friends, stands at his desk at the Kodaikanal Solar Observatory and carefully takes out a postcard-sized plate of glass as thick as a windowpane from an aged envelope. He slides the glass plate under a yellow light. Immediately, an image snaps into view: it’s a photograph of the sun from November 13, 1932 – a moment from a past long gone.

Sathish scans the photograph in a massive space-age scanner, as part of the digitisation project underway at the observatory, which aims to scan and upload all the archives going back to 1904. This is the start of a typical day in Sathish’s life, going back in time – and space.

“There are students too, doing research here, who visit the lab. I digitise their latest observations or help them locate older data in the archives,” Sathish says. He has been working at the Kodaikanal Solar Observatory since 2009, digitising the photographic glass plates of the sun, along with sun charts – hand-drawings of the sun, usually in pencil, highlighting sunspots and other features.

But Sathish’s association with the observatory goes back much further than 2009, all the way to his great-grandfather who joined the place in the early 1900s, when it was first set up.

“My great-grandfather V Poomban hails from Poombarai. He was hired by the British as a peon,” Sathish says. Since then, Poomban’s son, grandson and great-grandson have all ended up working at this historic institution, either as support staff or directly assisting the scientists in observing the sun every day.

My first visit to the Kodaikanal Solar Observatory was back in early 2020, when I initially visited Kodaikanal, right before the pandemic. When I entered the campus, strategically situated at one of the highest points in Kodaikanal, the sounds of traffic slowly faded amidst the towering oaks and pines.

I took the museum tour with a gaggle of school children and marvelled at the live solar image, shifting in real time as the Earth spun, and the various charts and graphs with information on the closest star ordering our days. After the tour, I snuck away to roam the sprawling grounds with its massive domed telescopes and tall trees, the soft February breeze whispering in my ears.

Sathish grew up roaming these grounds. “I have peered through the windows, watching the scientists and technicians work, since I was a child,” he says.

The Kodaikanal Solar Observatory is a pioneering institution for solar physics. It celebrates turning 125 this year with a series of events which began this February. Its earliest claim to fame lies, in part, with the late John Evershed, an English astronomer who first observed the flow of gases across sunspots from here in 1909. This phenomenon was christened the Evershed Effect.

The study was so comprehensive and foundational that “little has been added to our information on it in the subsequent half century”, according to the Indian Institute of Astrophysics website. When I ask him about it, Sathish gets excited. “My great-grandfather worked with Evershed,” he says, beaming.

The sun has been studied over the last few centuries for various reasons, including solar eclipses, sunspots – cooler regions on the sun’s surface that emit electromagnetic radiation – and sometimes solar flares, which affect the earth’s atmosphere. A guide at the Kodaikanal Solar Observatory museum explained to us that the appearance of sunspots is thought to be connected to the monsoon patterns on Earth.

In fact, the Kodaikanal Solar Observatory came into being through the relocation of the erstwhile Madras Observatory to a higher, sunnier location after the Great Famine of 1876-1878 in South India, which occurred after an intense drought and subsequent crop failure and led to the loss of 5.6 million-9.4 million lives, according to some estimates.

This tragedy, along with pressure from European solar scientists “who wanted the benefit of India’s sunny days for their research” led to the establishment of a new observatory in the hills of South India.

Since the early 20th century, the Kodaikanal Solar Observatory has continued to facilitate crucial research in solar as well as astrophysics. The observatory, started in a small shed in 1901 – it is now spread out over numerous buildings and telescopes – has been recording images of the sun daily for more than a century.

This means it has one of the oldest and most exhaustive archives of the sun in the whole world. Sathish and his family have been working behind the scenes of this remarkable endeavour throughout, whether it is assisting the scientists, handling security or digitising the archives to enable further research.

According to a 1928 Kodaikanal Solar Observatory bulletin, it was Poomban, Sathish’s great-grandfather, who first spotted a brilliant daylight comet – thought to be De Vico’s comet, which shows up in our skies every 74 years – one early December morning in 1927.

While setting up the facility for the scientists, Poomban noticed “something bright quite near the sun” and immediately alerted the observatory staff. PR Chidambara Ayyar, in charge of the scientists, writes, “There was the bright head and there was the tail directed away from the sun. The head was clearly brighter than Venus seen some distance ahead in the west.”

Ayyar went on to draw the comet by hand, as it could not be observed through the telescope because of the glare of the sun “flooding the instruments”. Unfortunately, the express telegram dispatched to the Madras Observatory that morning to verify the “apparition” never reached its recipient, so valuable observations of the comet were lost.

The only other observation of the De Vico comet until then had occurred in 1846, when it was discovered. The next official observation occurred only on 25 June 1996. Poomban almost made history that day in 1927.

This was the start of a curious family legacy that has endured for more than a century. “My grandfather P S Subramanian joined the observatory at the age of 24, sometime after he left the military in 1946. He was the head peon.”

There is not much more information about his grandfather’s time at the observatory, but Sathish credits Poomban for passing down his dedication to the Kodaikanal Solar Observatory to three further generations.

After Subramanian, his son S Padmanabhan (Sathish’s father) joined the observatory in 1974 as a security guard. Two years later Subramanian passed away. Padmanabhan continued to work there for the next 36 years and retired as the head of security in 2014.

Today Sathish has followed in his ancestors’ footsteps. Despite having no formal training in physics (he is an MBA graduate), he joined the observatory in 2009 and started out cleaning the photographic glass plates that had images of the sun.

Later, with encouragement from his scientist colleagues, he even made observations through the six-inch twin telescope (one of the oldest extant scientific telescopes) that is housed in an unassuming pale yellow building on campus.

Now, Sathish is project assistant of the digitisation programme at the observatory. “I have learnt these processes out of interest,” he says. ‘People who have worked here for 35 years have taught me how to digitise the glass plate images of the sun, draw sun charts and so on.’

There are approximately 2,00,000 glass plates in the Kodaikanal Solar Observatory archives, dating back to 1904, and Sathish, along with the digitisation team, has set down all of these records that astrophysicists and solar physicists use till this day, for posterity.

The process of choosing a suitable location for an observatory to replace the one in Chennai was long and drawn-out. Finally, the government astronomer for Madras Michie Smith arrived at two options: Kotagiri and Kodaikanal.

After extensive observations of the sun (including the steadiness of its image), Venus, Saturn, star clusters, star trails and nebulae at both locations, and considering their altitudes, he declared Kodaikanal the clear winner, with the most suitable climate.

The spot chosen by Smith was “more than a 1,000ft higher than the highest spot in Kotagiri”. And thus, “Books and instruments were transferred from Madras to Kodaikanal and sent up the ghaut in the dry weather before end of March 1899. About 1,000 coolie loads reached Kodaikanal.”

More than 100 years and 10 solar cycles later, Sathish is working assiduously to digitise and preserve all the invaluable data at Kodaikanal Solar Observatory for current and future generations.

The observatory’s archives, with more than a century of invaluable data, are extraordinary in themselves. A short YouTube documentary shows temperature- and humidity-controlled rooms with endless wooden cabinets full of glass plates encased in paper envelopes.

Sathish maintains the archival room with the utmost dedication and attention to detail. ‘You won’t get this quality of data anywhere else,’ he says. ‘If you see the images of solar flares and prominences on glass plates, they are crystal clear, better than the digital CCTV observations that are in use now.’

The Kodaikanal Solar Observatory is also known for its collaboration with a number of other observatories in Europe and the United States, who use its solar and astronomical data for research.

Awestruck by the historic and scientific scale of his and his colleagues’ work, I ask Sathish the obvious question: How does he feel about his job, after a decade at the Kodaikanal Solar Observatory?

“I like that the observations I digitise are published in prestigious journals. I compile the raw data and send it to IIA, Bengaluru. When my work is acknowledged in scientific publications, it gives me immense satisfaction,” he replies.

Sathish and his observatory colleagues’ work has led to crucial breakthroughs in solar physics, including the discovery of the migration of sunspots to the solar equator, helping predict future solar cycles and the discovery of oxygen and hydrogen lines in the solar atmosphere, to name a few.

It isn’t just the recognition for him, though. Sathish dearly values the years of hard work put in by his father, grandfather and great-grandfather, along with their peers. “They worked here with very limited resources and facilities, and their efforts must not go to waste.”

These days the sun shines brightly over the Palani Hills, I’m told, bringing respite to locals after a gloomy winter. The sunshine and clear weather, however, also herald the wildfire season, threatening crops and livelihoods.

Personally, this time of the year is forever tied to my first memories of Kodai: traipsing around in spring – a month before the pandemic would swallow us – my city eyes popping in disbelief at the shocking reds, blues, yellows, greens and purples (jacarandas, hydrangeas, poinsettias, angel’s trumpets) of the hillside, reading by the lake, watching the sunrise from Greenlands, easing out of heartbreak.

For a year-and-a-half, I watched the sun (and moon) rise from my tiny cottage, cooked meals, worked on my book, sat with myself. I lived by daylight, wrapping up errands in town by lunchtime, and inevitably retired to my room by nightfall.

Although I find it hard to believe in a god, there is something sacred in this rhythm. It taught me things about myself, my mistakes, my desires. Now, almost six months after leaving Kodai behind for a new life, I wonder what it means to live and die by the sun.

Sathish wears the weight of this legacy lightly. I ask if someone else will follow in his footsteps and keep the family tradition of watching “the sun god” – which he likens to a “prayer” – alive.

“I am married with two daughters,” Sathish says proudly. Then pulling out his phone, he shows us photos of them. A tiny girl in a shiny dress is pointing excitedly at a white light image of the sun on a computer. “I hope my daughter can join the observatory someday.”

Visit the Kodaikanal Solar Observatory’s astronomy museum through the week, all year, 9 am-4 pm. Their daily night skywatch is usually held from 7-9 pm. For more information, call 04542 240 588 or visit the Indian Institute of Astrophysics website. To follow the observatory’s activities and for updates, follow them on Instagram.

Kartikeya Jain is a freelance writer, editor and translator from Delhi. Kartikeya is a 2022 South Asia Speaks fellow and their work appears in Scroll, Deccan Herald, Thelallantop.com and Nether Quarterly.

This article was first published by The Kodai Chronicle.