BENGALURU: While multiple scientific agencies, including NASA debate, whether or not it was a meteorite strike that killed a bus driver in Vellore last fortnight, an India-origin space scientist says India’s space establishment ought to have a space rock surveillance system in place.
Had such a system been set up, as it ought to be, we would have known whether it was indeed a meteorite or a piece of satellite junk that killed driver Kamaraj at the Bharatidasan Engineering College, says Dr Chaitanya Giri, who was earlier with Max Planck Institute for Solar System Research in Germany and is currently with the Earth Life Science Institute in Tokyo.
Dr Giri believes that the Indian Institute of Astrophysics (IIAP) in Bengaluru has been hasty in certifying it as not a meteorite strike. Analysis of a suspected meteorite is the not the job of astronomers, but the work of the Geological Survey of India (GSI), he said in an email interview with IANS.
The GSI stepped forward to test the Vellore object last week, but IIA astronomers had already discounted the episode offhand.
Dr Giri said, "The verdict -- whether it was a meteorite or not -- should be supported by peer-reviewed evidence. The GSI is the authority on meteorite curation and not IIAP whose faculty are mainly astronomers," Giri said.
Further, IIAP scientists did not collect the samples themselves but tested a sample given by the police "which is not the most appropriate thing to do," he said.
"I also do not know if they looked for the presence of iridium, an element that you do not get on Earth and is predominantly extra-terrestrial in origin. Hence I do not consider IIAP's sampling and verdict at face value."
The space scientist says the Vellore episode underlines the need for India to have put in place meteor reconnaissance infrastructure and evolve a national meteor disaster preparedness policy.
"Catastrophies originating from outer space are no fiction," Chaitanya Giri. “Such catastrophies are potential and credible threats to our national interests.”
Giri said the US , European Union, Japan, Russia and Canada all have space object tracking systems in place, and so should India, even if potential destruction due to a meteorite strike may sound alarmist.
"Space-capable India has not joined this club," Giri said.
For instance, a seven-foot wide piece of satellite junk fell to the ocean off the southern coast of Sri Lanka on November 13, 2015. It was identified by a US ground-based sky survey infrastructure while its fall trajectory was projected by the European Sky network, Giri said.
So you think meteorite hits are rare
The damage potential of a meteorite strike depends on the scale of the event. While it is true that killometres-wide meteorites fall once in several thousand years, smaller metre-scale meteorites fall frequently and unleash limited regional destruction.
India's prehistory is dotted with meteor hits of different sizes.
- The Lonar lake in Maharashtra is the result of a meteorite strike (2 km wide)
- Ramgarh in Rajasthan is even bigger, 4 km wide
- An 11-km-wide meteorite that hit Dhala in Madhya Pradesh could have unleashed energy many times higher than the largest atomic detonation.
Not that recent years have been bereft of meteorite activity in India’s vicinity.
- A 20-year (1994-2013) global map released by NASA in 2014 shows numerous metre-scale meteors exploding over the Indian Ocean region and the Indian sub-continent with energy approximately equivalent to the atomic bomb dropped over Nagasaki in 1945
- In the past 15 years, the Geological Survey of India has reported numerous meteorite falls -- mostly centimetre-scale chunks -- from all over India.
- In February 2013, a meteor, 20 m in diameter, exploded 30 km above the city of Chelyabinsk in Russia with an energy approximately 25 times more than the Nagasaki bomb, causing thousands of human injuries and damage worth billions of dollars.
- Bangkok experienced meteorite falls twice in September 2015.
- Nearer home, on February 27, 2015, a meteor exploded over Kozhikode, Malappuram, Palakkad and Thrissur in Kerala to finally impact at several locations in Ernakulam district.
- A seven-foot wide piece of satellite junk fell to the ocean off the southern coast of Sri Lanka on November 13, 2015.