New Delhi: While India’s space agency has delayed its first effort to dock two small, experimental satellites, whose success is crucial for planning manned missions, experts say the trial run will generate vital data for such manoeuvres in the future even if it is not fully successful.
On 30 December, Indian Space Research Organisation (Isro) launched two satellites of 220 kilograms each—SDX01 ‘Chaser’ and SDX02 ‘Target’—aboard its final mission of 2024 on the workhorse Polar Satellite Launch Vehicle (PSLV) rocket. They were designed to move in a predetermined trajectory, before physically ‘docking’ or linking with each other on 7 January.
Isro, however, aborted the space docking experiment (Spadex) citing technical issues. A second docking move, scheduled for 9 January, was postponed too. An official statement from Isro on 12 January said, “A trial attempt to reach up to 15m and further to 3m (in proximity between the two satellites) is done. Moving back spacecrafts to (a) safe distance. The docking process will be done after analyzing data further. Stay tuned for updates.”
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Union minister of state for space Jitendra Singh had told the media on 31 December that the docking experiment would be a key milestone for Isro. “All of the planned missions, such as the Chandrayaan-4 moon mission, the Gaganyaan manned mission, and the Bharatiya Antariksha Station (BAS, or Indian Space Station), would require docking as a key mission detail. The Spadex experiment is therefore crucial for Isro.”
A senior official with direct knowledge of the matter said that Isro’s approach is “to go slow but be certain than attempt success at any rate”.
“There are multiple factors that influence the success of a mission in outer space—it’s not as simple as it looks to the average eye. The Spadex mission is still generating valuable data for Isro’s future missions, and the ability to make a manoeuvre that brought the two satellites to within 10 feet of each other is a key success in itself,” the official said. “Of course, a physical docking process is the final frontier, but there will be more opportunities for Isro to prove itself.”
At stake is a seat at the table of the world’s elite space powers—the US, Russia and China.
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“One of the key constraints for Isro is the available budget—it does not make sense for Isro to build large sensing satellites in a docking experiment,” said Narayan Prasad Nagendra, chief operations officer at Dutch space services firm Satsearch. “But, pulling off a docking attempt in the first go with small satellites is difficult for multiple factors, such as the kind of equipment available aboard a spacecraft to conduct manoeuvres, the propulsion power available at hand, and also the surface area available with the satellites to dock with each other.”
The docking experiment is expected to continue without a definite clarity on its immediate future. Queries emailed to Isro seeking comments on its current mission as well as a potential future experiment did not immediately elicit a response.
Why the stall?
The mission, however, remains important. Chaitanya Giri, space fellow at global policy think-tank Observer Research Foundation, said that one key reason for Isro’s slow approach is its stature in the domestic space industry.
“It’s important to understand that there is immense public pressure on Isro to pull off successes—its scientists are almost expected to be superhumans, without the kind of hiring powers that private firms are increasingly generating,” said Giri. “Isro is also closely linked with the government, for which any mission failure would give cold feet in terms of utilizing funds of the public exchequer. Any mission failure would create budget constraints for following attempts, for which Isro is likely being doubly cautious of where the Spadex mission stands at the moment.”
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Nagendra and Giri said a successful physical docking would be imperative for Isro to conduct its future missions. Moreover, Nagendra said, global space powers coming together to create a unified space port for compatible docking won’t be easy.
India is building its own space docking technology instead of licensing existing ones from the US or Russia to ensure proprietary in space. Experts and global think tanks have highlighted that the threat of satellite interception could be a concern in future, and building a proprietary docking mechanism could be a key way to keep a nation’s satellites safe from foreign intrusions. Such intrusion attempts, for instance, can lead to disrupted communications.
“Attempts made by a satellite to dock on a foreign one would be considered an act of war,” Nagendra said. “For this, it’s important that nations build their own, proprietary space docking interfaces.”
