Tracking the Unseen in Low Earth Orbit
U.S.-India “Dual Horizons” challenge winner Digantara is strengthening space security with a satellite tracking system that eliminates “blind spots” in the Indo-Pacific.
Digantara uses a moving platform in space, which is monitored from Earth and offers a persistent “visual” on assets, allowing for more frequent data collection and a much higher degree of accuracy. (Photograph courtesy Digantara Industries)


By Krittika Sharma, ( US Embassy, New Delhi)

In the silent, vacuum-packed expanse of Low Earth Orbit (LEO), a high-stakes game of hide-and-seek is unfolding. Today, more than 24,000 objects, ranging from multibillion-dollar satellites to jagged shards of space junk, hurtle through the void. Within five years, that number is expected to reach 70,000. For countries, the challenge is no longer just managing congestion and collision risk, but ensuring their assets are protected from intentional interference by hostile or rogue actors.

In a contested environment, it is essential not only to see an object on radar but to understand its intent. When a satellite does not want to be found, or when it performs an unpredicted maneuver, traditional ground-based tracking often fails. To bridge this gap, the U.S. Department of War’s Defense Innovation Unit (DIU), in partnership with the U.S. Space Forces-Indo-Pacific and the Space Domain Awareness Tools, Applications, & Processing Lab , with support from India’s Innovations for Defence Excellence (iDEX), launched the “Dual Horizons: U.S.-India Satellite Tracking Challenge ”—a bilateral effort to advance the next generation of space-domain awareness.

Solving the congestion crisis

To understand the problem, imagine operating a self-driving vehicle in a desert with no cameras or GPS. The only way to verify its location is to wait for it to pass a specific, static checkpoint. Now, add thousands of other vehicles moving at 17,000 miles per hour. If one vehicle swerves unexpectedly, it is effectively “lost” to the system.

This is the reality of traditional space situational awareness. Standard methods rely on predictable orbital math; if a satellite moves according to the “script,” we know where it is. But modern adversaries use camouflage and deceptive maneuvers to vanish. Once a satellite deviates from its predicted path, reacquiring it can take hours or days, leaving critical infrastructure vulnerable.

Anirudh Sharma, founder of Digantara, a Bengaluru-based start-up and one of the winners of the Dual Horizons challenge, points to a massive geographic vulnerability. Currently, the United States maintains primary sensors in Australia and South Africa. “In between, there’s a huge gap,” Sharma notes, adding that Digantara is working with U.S. agencies to track satellite activity in this region.

Digantara’s winning solution, SPECTRE (Surveillance and Persistent Evaluation for Characterising and Tracking), aims to light up these blind spots. By shifting the perspective from the ground to the sky, SPECTRE tracks space objects from orbit.

“Traditionally, systems are ground-based—radars or telescopes,” explains Sharma. “Our solution tracks from orbit, meaning we bypass atmospheric distortions and range issues.” By utilizing a moving platform in space, Digantara achieves a persistent “visual” on assets, allowing for more frequent data collection and a much higher degree of accuracy.

Strengthening the bilateral shield

While most commercial firms rely on the U.S. Department of War “catalog” to know what is in the sky, Digantara is building its own independent repository. Its sensors can detect objects as small as a softball, providing a unique layer of intelligence.

This independence has not made the start-up a competitor but a vital partner. Digantara currently operates under a data-sharing agreement with the United States, effectively merging its unique blind-spot data with the existing U.S. military catalog.

Interoperability is the “plug-and-play” secret to its success. SPECTRE is designed to integrate seamlessly into existing mission networks, allowing commanders to access real-time data without needing to rebuild their software from scratch. With offices now in the United States and deep ties across the Indo-Pacific, Digantara is positioned as a systems integrator.

The new frontier: Beyond tracking

The success of Digantara is a case study in U.S.-India synergy. Sharma’s path was forged through U.S. Department of State programs like the International Visitor Leadership Program, which helped him build connections to embed his team within the American defense ecosystem.

“We plan to invest further in our U.S. office as part of our expansion into the U.S. market. We are building a dedicated team and facility that will focus on satellite and payload assembly, as well as missile defense applications,” says Sharma. “Our recent selection for a U.S.-based program has given us the confidence and foundation to make that investment and launch this initiative.”

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Hindusthan Samachar / Indrani Sarkar


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