India's destruction of one of its satellites added less than half of the debris usually left over after a major satellite launch, a former chief of the Defence Research and Development Organisation (DRDO) said, countering a statement from US space agency NASA that had criticised the exercise. Branding the anti-satellite test a "terrible thing", the head of NASA on Monday said "Mission Shakti" had created 400 pieces of orbital debris and led to new dangers for astronauts aboard the International Space Station.
But speaking to NDTV, V K Saraswat, a missile scientist who has led the DRDO in the past and is currently a member of the Indian government's policy think-tank NITI Aayog, said this was not the case.
"Today in space there are a few million [pieces of] debris which are floating around. Every satellite launch which you do leaves anything between 100-150 fragments, they could be small bolts, they could be heat shields, they could be anything," he said.
"These fragments keep floating around because as soon as you get out of atmosphere nothing comes back, it always remains there and keeps on revolving because it is at the same speed of the satellite," he said.
"So when they keep revolving, they have tendency to come in the way of other objects that are going to be propelled, that is why internationally, there is program today to remove debris as much as possible and India is signatory to that," Dr Saraswat said.
"Launching an anti-satellite missile does not create even 50 per cent of what we are doing while launching a large satellite," he said.
Speaking to NDTV, Vipin Narang, a professor of political science and a specialist on strategic studies at MIT in Boston, US added, "Let's be clear there is only a 1 per cent risk of debris hitting the International Space Station, as as the NASA chief says there has been a 44 per cent increase in the risk of the ISS being hit by space junk created by the Indian A-SAT test, even then the risk goes up to a mere 1.44 per cent."
Since the Soviet Union launched the Sputnik satellite in 1957, more than 8,000 satellites have been shot into space, creating innumerable pieces of debris.
Of these, 2,000 are functional in orbit giving an idea of who creates more space junk.
At the top spot is the United States which owns 800 satellites in orbit, followed by 280 of China and 159 of Russia. India trails way behind with just 48, making its debris footprint far smaller than other major countries.
But Jim Bridenstine, addressing NASA employees five days after India shot down a low-orbiting satellite in a missile test to prove it was among the world's advanced space powers, said India's move was "unacceptable".
Not all of the pieces left after India's test were big enough to track, Mr Bridenstine said. "What we are tracking right now, objects big enough to track -- we're talking about 10 centimeters or bigger -- about 60 pieces have been tracked."
The Indian satellite was destroyed at a relatively low altitude of 300 kilometers, well below the ISS and most satellites in orbit.
But 24 of the pieces "are going above the apogee of the International Space Station," said Mr Bridenstine.
"That is a terrible, terrible thing to create an event that sends debris at an apogee that goes above the International Space Station," he continued, adding: "That kind of activity is not compatible with the future of human spaceflight."