Weapons and Kit

Why is the US investing $1.3bn into a hypersonic weapons satellite tracking system?

The move aims to expand and enhance the US' ability to counter increasing missile threats from Russia and China.

The era of hypersonic weapons is forcing the world of defence to re-think its detection systems.

On Monday, the Pentagon announced that the US will spend $1.3bn to develop advanced satellites that will be able to better track and detect hypersonic missile threats.

The US Department of Defense announced two contracts that will look to put the detection and tracking systems in orbit by 2025.

Director of the US' Space Development Agency, Derek Tournear, said the contracts will provide 28 satellites.

It comes as the US looks to expand and improve its ability to counter growing threats posed by Russia and China.

Mr Tournear said the new satellites will be able to detect the launch of a hypersonic missile and follow it as it changes course, calculating where it is going and providing data for interceptors to be launched.

Hypersonic weapons are defined as anything travelling beyond Mach 5 - that's five times faster than the speed of sound or around 6,100km/h (3,800mph).

Traditional intercontinental ballistic missiles exceed these speeds but follow a predictable trajectory.

They can be detected early in flight, making it possible for them to be intercepted.

Watch: What is a hypersonic missile?

Hypersonic missiles work differently, exploiting physics using drag and friction so they can fly in all directions like an aircraft but at very high speeds, making them very tricky to stop.

Douglas Barrie, a military aerospace expert from the International Institute for Strategic Studies (IISS), a global security, political risk and military conflict think tank, says hypersonic missiles bring a new challenge.

He told Forces News: "These capabilities are now exiting the labs.

"Both Russia and China have hypersonic boost glide systems entering their inventory, probably in comparatively small numbers so far and at different range categories, but there is an obvious challenge emerging."

It was reported by US officials that China tested a hypersonic missile, and the Russian military said it carried out a series of strikes on Ukrainian military facilities with long-range hypersonic and cruise missiles in March.

Mr Barrie said the US developments are "all part of of a kind of architecture which is intended to help you deal with this threat".

"As with any kind of defensive architecture it is never going to be foolproof, it's never going to be impermeable, but against a small number of threats, your chances of dealing with it will eventually be pretty high.

"And against a higher number of threats then you may be able to cut the numbers down significantly. 

"So it's part of an overall or much wider programme which will include eventually interceptors, ground-based systems, more ground-based systems, possibly more space-based systems that allows you to begin to deal with this kind of threat," he added.