The Space-based Kill Assessment (SKA) experiment will be a network of small sensors hosted on commercial satellites. The individual sensors house three photodiodes used to collect the energy signature of the impact between a threat ballistic missile and an interceptor of the Ballistic Missile Defense System.

In Fiscal Year 2014 several events prompted the Missile Defense Agency to start SKA. The Fiscal Year 2014 National Defense Authorization Act directed the Missile Defense Agency to address hit and kill assessment for the Ballistic Missile Defense System. An internal study on space highlighted strategies that could provide sensor capabilities at lower price points. In addition, a once in a decade opportunity for hosting sensors on commercial space platforms became available. In April 2014 after coordination with the combatant commands and Congressional staff the Missile Defense Agency began the SKA experiment.

The Johns Hopkins University Applied Physics Laboratory in Laurel, Maryland is developing the SKA sensors.

The network of SKA sensors is projected to be on orbit in 2017. They will be placed on orbit according to the launch plans of the commercial host.

Initially the SKA payloads will be operated by the developer, the Johns Hopkins University Applied Physics Laboratory; however the Missile Defense Agency is planning for the future when operations of the SKA sensors will transition to the Missile Defense Integration and Operations Center in Colorado Springs, Colorado. The transition date has not yet been established.

The Missile Defense Agency strives not only to provide an ever increasing ballistic missile defense capability but also to decrease the cost. One significant way to reduce the overall cost is to reduce the number of interceptors needed in a missile defense fight. A key element of the missile defense fight is the determination of whether or not a threatening missile has been eliminated, aka “kill assessment.” The faster we can determine a threatening missile has been eliminated, the fewer the number of interceptors are needed in the fight. Electro-optical / infrared sensors, such as the ones on SKA, are well suited to perform a kill assessment from space especially when paired with other sensors in the Ballistic Missile Defense System for an integrated kill assessment picture.

To reduce the overall cost of the SKA experiment all of the parts used in the sensor are commercially available today. All together the sensor consists of: a housing to hold the three photodiodes; motors to move the housing; a circuit card to control it and cabling to connect the two.

More than ten years.

The Missile Defense Agency has chosen to host the SKA sensor network on satellites owned by the commercial sector. In a traditional space program the DoD would have specified exacting requirements, many of which are specifically tailored for the military and can be expensive to satisfy. The SKA sensor network is in the unique position of being able to accommodate commercial practices and so the program took advantage of the billion-dollar investment industry had already made in their satellites and communications network and completely sidestepped those costs.

No, SKA sensors will only record the electro-optical signature of the intercept. STSS is and PTSS was to be a missile tracking system – both different and more complicated systems than SKA.

SKA will work with other sensors and systems on the kill assessment mission. If SKA is successful it will be validation that kill assessment data is useful to the warfighter and the Missile Defense Agency will work with the warfighter to determine what the next steps should be.

Check out the information on our Sensors page, where you can find fact sheets for many of the sensors. Visit our Sensors Media Gallery to view images and video.

All of the elements of the BMDS are described in our System section.
If you still have questions, check out the FAQs for:

• Aegis Ballistic Missile Defense (BMD),
• Command and Control, Battle Management, and Communications (C2BMC),
• Ground-based Midcourse Defense (GMD),
• PATRIOT Advanced Capability-3 (PAC-3), and
• Terminal High Altitude Area Defense (THAAD).