1. Hypersonic weapons are manoeuvrable weapons that can fly at speeds in excess of Mach 5, five times the speed of sound.
2. The speed of sound is Mach 1, and speeds up to Mach 5 are supersonic and speeds above Mach 5 are hypersonic.
3. Ballistic missiles, though much faster, follow a fixed trajectory and travel outside the atmosphere to re-enter only near impact.
4. Hypersonic weapons travel within the atmosphere and can manoeuvre midway which combined with their high speeds makes their detection and interception extremely difficult.
5. The radars and air defences cannot detect hypersonic weapons till they are very close and have little time to react.

1. Hypersonic glide vehicles (HGV) - Launched from a rocket before gliding to a target
2. Hypersonic cruise missiles (HCM) - Powered by high-speed, air-breathing engines, or scramjets, after acquiring their target.

1. Russia had announced that it had successfully test-launched a Tsirkon hypersonic cruise missile from a Severodvinsk submarine deployed in the Barents Sea which hit a target 350 kms away.
2. The Financial Times had reported that China tested a nuclear-capable hypersonic missile in August that circled the globe before speeding towards its target, demonstrating an advanced space capability that caught U.S. intelligence by surprise. This was later confirmed by U.S. military officer Gen Mark Milley, Chairman of the joint chiefs of staff. However, China has denied that it was nuclear capable.
3. The USA has active hypersonic development programmes but is lagging behind China and Russia because most U.S. hypersonic weapons, are not being designed for use with a nuclear warhead.
4. Number of other countries - including Australia, India, France, Germany, and Japan—are also developing hypersonic weapons technology.

India operates approximately 12 hypersonic wind tunnels and is capable of testing speeds of up to Mach 13.

According to the United States Congressional Research Service (CRS) India is also developing an indigenous, dual-capable hypersonic cruise missile as part of its Hypersonic Technology Demonstrator Vehicle (HSTDV) program and successfully tested a Mach 6 scramjet in June 2019 and September 2020.

This test was carried out by the Defence Research and Development Organisation (DRDO) and demonstrated the scramjet engine technology, a major breakthrough.

The quest for Hypersonic weapons across the globe is leading to the arms race.

Given the rising tensions between the U.S., China and Russia as also the worsening geopolitical situation worldwide, the focus for hypersonic weapons is only set to accelerate more countries to invest significant resources in their design and development.