Atmanirbharta in critical space technologies such as atomic clocks and cryogenic engines is essential for space sovereignty. Comment.

Space sovereignty means a nation can reach, run and sustain its space assets without needing a foreign power's permission. Two technologies show why. The cryogenic engine decides whether India can reach geostationary orbit on its own. The atomic clock decides whether its navigation satellites keep working. Self-reliance in both is therefore essential, though on its own it is not enough.

Why these technologies decide sovereignty

• Access to orbit: GSLV's indigenous cryogenic upper stage (liquid hydrogen fuel with liquid oxygen) replaced the earlier Russian-supplied stage [4][7]. NavIC's NVS satellites now fly on an Indian rocket.
• Time is navigation: a satellite whose clock has failed cannot give navigation. IRNSS-1F's procured clock failed in March 2026, and the satellite now only broadcasts messages [2].
• Strategic denial: NavIC's encrypted Restricted Service for the armed forces is credible only if no foreign supplier can hold back its critical parts [7].

Progress achieved

• NVS-01 (2023) carried India's first indigenous atomic clock [1].
• User segment: a MeitY–C-DAC–Signalchip MoU covers making and deploying 10 lakh indigenous NavIC + GPS receivers [6].

Gaps: self-reliance is still incomplete

• Partial dependence: NVS-03 still carries procured clocks alongside an indigenous one [7].
• Indigenous is not the same as reliable: NVS-02 is stranded in transfer orbit. The likely cause was a connector fault in both the main and the backup pyro-valve paths [5].
• Continuity gap: in July 2026 only 3 satellites were giving positioning, navigation and timing. Standalone positioning was impossible, though the timing service worked [3].

Way forward

• Fly only indigenous clocks on NVS-04 and NVS-05, which are in advanced stages of development [3].
• Check backup systems for common-mode faults (one fault that disables both main and backup) before launch, as the NVS-02 review showed is needed [5].
• Keep a ready spare satellite and publish regular status reports, so the constellation does not fall below 4 working satellites again [3].

Cryogenic engines and atomic clocks are where India's space autonomy either holds or fails. India has built both at home, but the system is only as strong as its weakest imported or untested part. Full indigenisation, backed by reliability engineering and spares, will turn NavIC from a launched system into a sovereign one, in line with the goals of Atmanirbhar Bharat and the Indian Space Policy 2023.