Is India's Drishti satellite tumbling in space? GalaxEye founder answers

Open-source satellite observations triggered questions over whether GalaxEye's Mission Drishti is slowly tumbling in orbit.

In Short

• SatNOGS observations showed different telemetry patterns across separate radio passes
• An early May 3 pass carried a strong and steady beacon
• A later pass appeared weaker, with signals fading during transmission windows

Days after the launch of Mission Drishti, India’s first privately built synthetic aperture radar (SAR) imaging satellite by Bengaluru-based startup GalaxEye, satellite trackers and amateur radio observers have raised questions over whether the spacecraft may still be slowly tumbling in orbit.

The concerns emerged from publicly available observations on the open-source SatNOGS satellite tracking network, where radio enthusiasts across the world monitor spacecraft transmissions.

Some independent trackers claimed the data suggested Drishti was rotating at roughly 3 degrees per second, equivalent to one rotation every two minutes, after deployment in orbit.

The speculation gained traction online after observers pointed to intermittent telemetry signals and changing beacon strengths seen in multiple waterfall plots captured during radio passes over ground stations.

WHAT IS MISSION DRISHTI?

Mission Drishti represents a major milestone for India’s private space sector.

Unlike conventional optical Earth observation satellites, SAR satellites can image the Earth day and night and through cloud cover by using radar signals, making them valuable for defence, disaster management, maritime monitoring, and agriculture.

IS GALAXEYE'S DRISHTI SATELLITE TUMBLING IN SPACE?

Analysis of two publicly available Satellite Networked Open Ground Station (SatNOGS) observations reviewed by this publication showed varying signal characteristics across different passes.

An earlier radio observation on May 3 showed Drishti sending out a strong, steady signal as it passed over Earth, the kind of pattern usually expected from a healthy satellite in low Earth orbit. Its onboard transmissions, or telemetry signals, were being received clearly by ground stations.

But in a later observation taken days afterwards, the satellite’s signal appeared much weaker and less consistent, fading in and out during parts of the pass. Some satellite trackers say this could happen if the spacecraft is slowly rotating in space, causing its antenna to periodically point away from Earth.

Others caution that weak or patchy signals can also result from ordinary factors such as ground-station conditions, antenna alignment, or interference.

Experts cautioned that such data alone cannot conclusively prove uncontrolled tumbling. Signal fluctuations can also arise from antenna orientation, polarisation mismatch, ground-station geometry, transmitter duty cycles, or weak reception conditions.

However, some independent satellite trackers argued the changing signal strength patterns could indicate slow spacecraft rotation or incomplete attitude stabilisation following deployment.

GALAXEYE RESPONDS TO CONCERNS

Responding to the concerns, GalaxEye founder Suyash Singh dismissed speculation that the spacecraft was facing major issues and criticised what he described as premature conclusions based on limited open-source data.

“Love the interest in Drishti,” Singh wrote in a social media response. “Never saw this level of interest or info floating around on previously launched sats.”

He further pointed out that some of the publicly circulated observations were from May 3, shortly after launch, and questioned whether critics had reviewed more recent telemetry.

“The date is 3rd May. Can you please share the latest analysis,” he wrote.

Singh also highlighted the complexity of operating a large SAR satellite during its early orbital phase.

“Have you ever done a LEOPs of 190 kg SAR-based satellite?” he asked, referring to Launch and Early Orbit Phase operations, the critical period immediately after deployment when spacecraft systems are activated and stabilised.

“Hold on buddy, not everyday these kind of satellites get launched. If something is wrong, we will let the world know. Keep calm.”

Spacecraft launched into orbit often undergo periods of slow rotation before attitude-control systems fully stabilise them.

Industry experts note that mild post-deployment tumbling is not uncommon, particularly for complex satellites carrying large deployable systems or radar payloads.

So far, GalaxEye has not indicated any anomaly with the spacecraft, and there is no public evidence suggesting Mission Drishti has lost operational capability.

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