ISSSP Reflections No.58, March 28, 2019
Authors: Rajaram Nagappa, Mrunalini Deshpande and S Chandrashekar
In a live address to the nation on 27th March 2019, Prime Minister Modi announced that India had shot down one of its satellite in low earth orbit. He referred to the ASAT mission as Mission Shakti and said that with this achievement India has become the fourth country after the US, Russia and China to be a space power. The Defence Ministry press release under the heading India Joins Select Group of Nations, Destroys Live Satellite in LEO read as follows:
“Defence Research and Development Organisation (DRDO) today successfully conducted an Anti-Satellite (A-SAT) missile test ‘Mission Shakti’ from the Dr AP J Abdul Kalam Island in Odisha. A DRDO-developed Ballistic Missile Defence (BMD) Interceptor Missile successfully engaged an Indian orbiting target satellite in Low Earth Orbit (LEO) in a ‘Hit to Kill’ mode. The interceptor missile was a three-stage missile with two solid rocket boosters. Tracking data from range sensors
The test has demonstrated the Nation’s capability to defend its assets in outer space. It is a vindication of the strength and robust nature of DRDO’s programmes.
With this India joins a select group of nations, which have such capability. The test has once again proven the capability of indigenous weapon systems.”
Lot of news and analysis has followed the test – mostly political in nature with sprinkling of technical guesswork. In this article, we have tried to study the available information and piece together a more coherent picture.
Kinetic Kill ASATs are not new. Both USA and the then Soviet Union had tried out kinetic energy weapon tests using both nuclear and conventional weapons during the cold war years. In September 1985, the US used a ‘kinetic kill mini vehicle’ on a modified anti-radiation missile air launched from a F-15 aircraft to intercept and kill the P78-1 Solwind Satellite. With this demonstration, the US did away with the use of a warhead and depended upon kinetic energy of impact for achieving an intercept and kill. All kinetic energy as well as kinetic impact tests create debris, but during the cold war years, space was not as congested as it is today and collision probabilities were low.
Both US and Soviet halted further testing and space became only a militarized arena till the Chinese carried out their own ASAT test on January 11, 2007. In this test, the Chinese targeted a non-functional weather satellite Fengyun-1C in a 863 km orbit with their DF-21D missile. China seems to have succeeded on the third attempt in destroying the satellite, but the interception created a debris field of about 3000 fragments of varied sizes orbiting around at 860+ km altitude. At this height, the orbital decay, reentry and burnup is expected to take many decades. The 600-900 km orbit is quite densely populated with Earth Observation and other satellites. The long-lasting debris of China ASAT poses a collision and damage threat to satellites orbiting at these altitudes. This, in turn calls for in constant vigilance and resorting to collision avoidance measures, based on a collision probability
The Americans followed with a test of their own on 21 February 2008 and destroyed an out of control reconnaissance satellite – the USA 193 at an altitude of 247 km. Debris was caused but remained in the orbit of the killed satellite. The orbit of the debris deteriorated fast ending in reentry and burning up of the debris in about 40 days.
The obvious lesson is a kinetic kill demonstration test should be carried out at low altitudes, so that the resulting debris has low orbital life and does no or minimal debris related damage. The 27th March test planned by DRDO would be planned with this objective. None of the ISRO operational or inactive satellites are in such low orbit. However, it is seen that the PSLV-C44 launch of 24 January 2019 carried Microsat-R, a satellite developed by DRDO.
Microsat-R described as an imaging satellite was placed in an orbit of 274 km. The Prime Minister also referred an orbit of 300 km. This would make it an ideal target for testing out the ASAT as the life of the resultant debris field from a kinetic test could be contained. In hindsight, it would appear that it was a meticulously planned secret mission.
DRDO has developed, as part of ballistic missile defence, missile interception capabilities. In this process, they would have developed kill vehicles with homing and maneuvering capabilities. Extending the concept for achieving satellite kill is well within DRDO capabilities. Also, DRDO has ballistic missiles, which have the capability of reaching 300 km altitude for carrying out interception. In fact, it can be inferred from the press release that the missile was a two-stage solid propellant missile and the third stage was the kinetic kill weapon. The press reports talk of a 3-minute time to hit the satellite. In 3 minutes, the satellite would have travelled about 1350 km. The interception of Microsat-R representing perhaps an area of 2 square metres, the related computations and real-time maneuvers needed of the warhead indicate the precision achieved in the missile guidance.
As early as 2011, Dr. V K Saraswat, who was SA to RM at that time, had asserted that India possessed the “capability to propel a kill vehicle in orbit”. It would appear from his TV interview of 27March 2019, that Government clearance was not forthcoming. It must also be recalled that in 2011 a low altitude interception satellite had not been planned or orbited.
Why an ASAT Test?
In recent times, an increase in
India has more than 45 operational satellites with 19 Earth Observation Satellites in LEO. ISRO has in recent times enhanced its capacity and has a busy calendar in 2019. According to the 2019 New Year message of Chairman, ISRO 32 missions comprising 14 launch vehicle, 17 satellite and 1 technology demonstration missions will be undertaken. A similar trend can be assumed for the subsequent years too as well as a busy period for small satellite launches with the newly developed Small Satellite Launch Vehicle. Add to these the growing realization and importance of defence satellites. Indian space assets in terms of
The ASAT test of
India’s Pokhran-2 test was a signal for deterring
nuclear war. On a similar thought, India’s ASAT test is a signal for deterring
a space war. If combined with the right mix of conventional military assets, India
can come up with a military strategy that links all capabilities for deterring