Aswin Sekhar Here

Perhaps Sekhar’s most cited contribution to planetary science involves the 1908 Tunguska event. For over a century, scientists have debated what exactly exploded over the Podkamennaya Tunguska River in Siberia, flattening 2,000 square kilometers of forest. Was it a comet? An asteroid? A piece of a dead planet?

In a series of rigorous papers, Aswin Sekhar brought modern computational fluid dynamics and orbital back-integration to bear on the century-old mystery. His work suggested that the Tunguska impactor was likely a low-density, fragile asteroid (a "rubble pile") rather than a comet. More importantly, he modeled how such objects fragment in Earth’s atmosphere—models that now inform planetary defense strategies.

But Sekhar’s planetary defense philosophy extends beyond impacts. He argues that we have become fixated on “planet-killers” like the dinosaur-ending Chicxulub impactor, ignoring the far more frequent threat of airbursts (like Chelyabinsk in 2013 or Tunguska). His research advocates for a global, decentralized network of small telescopes to detect meter-sized objects that currently slip past our survey telescopes. "We are not ready for the next Tunguska," he warned in a 2021 lecture, "because we are looking for mountains, not houses."

In the last five years, Aswin Sekhar has pivoted significantly toward a pressing, man-made threat: satellite megaconstellations. Projects like Starlink (SpaceX), OneWeb, and Project Kuiper (Amazon) plan to launch tens of thousands of communication satellites into Low Earth Orbit (LEO).

While many astronomers criticize these constellations for ruining photographic images, Sekhar takes a more holistic, almost ecological stance. In his 2023 paper in Nature Astronomy and multiple articles for Scientific American, he argues that we are witnessing "the industrialization of Earth’s orbit without an environmental impact statement."

Sekhar has coined the term "orbital light pollution" to describe the cumulative effect of satellite trails on professional observatories. His unique contribution is linking this to astrobiology and cultural heritage. He asks: If we cannot see the Milky Way from Earth because of artificial satellites, how will future generations develop a cosmic perspective? How will we detect faint, potentially biogenic signals from exoplanets if our instruments are saturated by reflections from LEO debris?

He is not anti-technology; rather, he advocates for binding international treaties on satellite reflectivity, maximum numbers per orbital shell, and mandatory deorbiting timelines. "The night sky is a global commons," Sekhar states frequently, "like the high seas or the Antarctic. No corporation should own the view of the stars." aswin sekhar

The advent of digital banking (eWallets like eSewa, Khalti, IME Pay) has introduced a new dynamic: the "Digital Sekhar." While physical currency notes are preferred for their tactile ritual value, younger generations increasingly accept transfers instantly. This shifts the Sekhar from a "sacred object" (physical money touched by the elder's hand during the ritual) to a "secular transaction."

Aswin Sekhar lived in a narrow apartment above a bookshop that smelled of dust and lemon oil. He learned small, perfect rituals early: waking to the light through the blinds at 6:07, brewing exactly one cup of black tea, and sorting the day’s errands into three neat columns on a torn postcard. Routine made the world predictable, which was what he wanted after his father left and the city taught him how little sense people made.

One Tuesday in late autumn, a dog pushed through the alley and nosed at the bookshop’s back door. Aswin, returning from the grocer, heard a muffled whine and found a small brindled creature with one ear flopped and a paper tag curled around its collar. The tag had a single word scrawled in ink: “Remember.”

He should have left it at the shop—pets were a complication—but the dog curled under his arm like a secret and fell asleep against his chest as though it had always belonged there. He named it Memory, half as a joke and half because the name made him feel braver.

Days stretched differently once Memory arrived. Aswin kept his postcard ritual, but added a new column: places to walk. They explored parks where the trees wore bronze leaves, alleys where old murals peeled into florals, and a riverbank where sunlight lay in golden bands over slick stones. Memory’s presence distorted small, sharp edges in Aswin’s life; grocery lines felt shorter, the landlord’s calls a little less urgent. He began to notice other people in the city as if a filter had lifted: a woman selling bright scarves who hummed a tune that matched a childhood lullaby, an old man who fed pigeons and occasionally looked at Aswin with the kind of pity that felt like care.

One evening, Memory began to tremble. At the vet’s, a thin-faced doctor listened to Aswin’s stammered questions and explained, gently, that Memory’s body was failing. There were tests, a prognosis with words like “progressive” and “no cure.” Aswin’s neat columns blurred. He tried to rearrange the world into something manageable: more walks, warmer blankets, mashed sweet potato at noon. When the tremors worsened, he sat on the floor of the living room and read aloud from a battered novel he’d never finished, as if voice could stitch time back together. He maintains an active presence on social media

On a cold morning, Memory did not rise. Aswin held him and felt how small the pulse had become, like a bird’s fluttering wing. There was grief, sharp and immediate, but it arrived with another, stranger feeling: an ache full of gratitude. He remembered the day the dog had appeared, the word “Remember,” the loosened routines that made room for unexpected kindness. He buried Memory beneath the maple on the riverbank, marking the place with a smooth pebble and a loop of twine.

Grief opened the door for other things. Aswin found himself saying yes more often. He helped the scarf seller carry boxes to her stall in winter and learned her name—Maya—and that she painted at night. He joined the old pigeon-feeder on Sundays, and they exchanged stories about small rebellions: forgotten youth theater roles, recipes that never quite turned out. At the bookshop, Aswin began working a few afternoons, stacking returned novels and recommending titles he loved. People started asking about him. He answered, slowly at first, then with more confidence.

One rainy afternoon, a child left a postcard on the bookshop counter. On it was a crayon drawing of a dog with one ear flopped, and the single word “Remember.” Aswin laughed then—half relief, half a tug at the place where grief still lived. He realized Memory had not been taken from him so much as had taught him how to carry something beautiful without it breaking him. The rituals remained—tea at 6:07, postcards—but now the columns included possibilities: a class to learn painting, a walk at dusk, a call to an old friend.

Years later, when the maple’s branches filled with green and the pebble had worn smooth, Aswin would sometimes pause on the riverbank and feel the memory of that small weight in his arms. He understood that lives are stitched together by tiny choices: the decision to keep a stray dog, the handful of extra minutes spent listening, the bravery of letting someone else in. Memory had been a beginning more than an ending, a small, insistent nudge that taught him how to hold loss and beauty in the same breath.

On quiet nights he still brewed his single cup of black tea. If the city felt overwhelming, he walked until the lights blurred, until the map of his routine felt like a softer thing. Somewhere in the ordinary—on a postcard, in a scarf seller’s hum, in the slow companionship of people who traded stories—he found a life large enough to survive and small enough to savor.

A critical observation in the study of Aswin Sekhar is the inflation of the "blessing." Three decades ago, nominal amounts (e.g., 1, 5, or 10 NRS) were standard. Today, social pressure has inflated these figures significantly. The Sekhar has transitioned from a symbolic token to a substantial financial burden for elders with large extended families. This shift challenges the traditional hierarchy, as the material value of the gift begins to overshadow its spiritual intent. for lower-income families

In 2020, the world was electrified by the announcement of phosphine gas in the clouds of Venus—a potential biosignature. Aswin Sekhar entered the fray not as a direct discoverer, but as a critical synthesizer. He co-authored papers examining non-biological sources for phosphine (such as volcanic activity or lightning) and challenged the astronomical community to adopt stricter standards for "biogenic claims."

His work on Venus highlights another facet of his personality: rigorous skepticism married to open wonder. He believes Venus is an under-studied world and has called for a new fleet of atmospheric probes. "Mars gets all the rovers," he jokes in interviews, "but Venus might have floating microbial cities in its temperate cloud layer. We need to look there with an open mind—but also a sharp scalpel for our data."

Unlike some researchers who hide in academic journals, Aswin Sekhar is a prolific science communicator. His writing has appeared in:

He maintains an active presence on social media (particularly X/Twitter and LinkedIn), where he breaks down complex orbital mechanics into simple diagrams and fierce ethical arguments. He also mentors young astronomers from the Global South, ensuring that Indian and African students get access to European telescope time.

Notable publications include:

The size and quality of the Aswin Sekhar serve as markers of social stratification. In the Newar community and other specific ethnic groups, the rigidity of the practice varies. Wealthier lineages often use the Sekhar to display affluence, converting a religious rite into a spectacle of economic status. Conversely, for lower-income families, the inability to provide a "respectable" Sekhar can induce social shame, highlighting the commodification of religious duty.