# Mission Delta 4

Mission Delta 4 (MD4) is a United States Space Force unit responsible for providing strategic and theater missile warning and tracking to the United States and its international partners. It operates three constellations of Overhead Persistent Infrared (OPIR) satellites and two types of Ground-Based Radars (GBRs) for the purpose of conducting strategic and theater missile warning and tracking. Additionally, DEL 4 provides tipping and cueing to missile defense forces, battlespace awareness to combatant commanders and technical intelligence for further analysis and manages weapon system architectures and ensures operations are intelligence-led, cyber-resilient, and driven by innovation, while postured to operate in a contested, degraded, and operationally-limited environment.
Activated on 24 July 2020, the delta is headquartered at Buckley Space Force Base, Colorado. On 31 October 2024 it was redesignated Mission Delta 4 and gained sustainment responsibilities, along with organic cyber defense and intelligence forces.

## History

DEL 4 was based on the previous 460th Operations Group, 460th Space Wing and 21st Operations Group, 21st Space Wing.
In lineage terms, the delta was originally established as 460 Operations Group (460 SW) on 2 August 2004. It was activated on 19 August 2004. It was redesignated as Space Delta 4 on 24 July 2020. Its status changed officially from a unit of the United States Air Force to a unit of the United States Space Force on 21 October 2020.
In 2023, Space Delta 4 assumed control of the U.S. Army's Joint Tactical Ground Station. On 31 October 2024 it was redesignated Mission Delta 4 and gained sustainment responsibilities, along with organic cyber defense and intelligence forces.

## Structure

| Emblem | Name | Function | Headquarters | Spacecraft and ground-based radars | Detachments |
| Squadrons ||||||
| | 2nd Space Warning Squadron | Missile warning, missile defense, battlespace awareness, and technical intelligence | Buckley Space Force Base, Colorado | Defense Support Program Space Based Infrared System | |
| | 3rd Satellite Communications Squadron | Military communications | Buckley Space Force Base, Colorado | | |
| | 5th Space Warning Squadron | Missile warning and space domain awareness | Buckley Space Force Base, Colorado | Joint Tactical Ground Station | Det 1: Naval Air Station Sigonella, Italy Det 2: Qatar Det 3: Osan Air Base, South Korea Det 4: Misawa Air Base, Japan |
| | 6th Space Warning Squadron | Missile warning and space domain awareness | Cape Cod Space Force Station, Massachusetts | AN/FPS-132 Upgraded Early Warning Radar | |
| | 7th Space Warning Squadron | Missile Defense and space domain awareness | Beale Air Force Base, California | AN/FPS-132 Upgraded Early Warning Radar Long Range Discrimination Radar | |
| | 10th Space Warning Squadron | Missile warning and space domain awareness | Cavalier Space Force Station, North Dakota | AN/FPQ-16 Perimeter Acquisition Radar Attack Characterization System | |
| | 11th Space Warning Squadron | Missile warning, missile defense, battlespace awareness, and technical intelligence | Buckley Space Force Base, Colorado | Defense Support Program Space Based Infrared System | |
| | 12th Space Warning Squadron | Missile warning and space domain awareness | Pituffik Space Base, Greenland | AN/FPS-132 Upgraded Early Warning Radar | |
| | 13th Space Warning Squadron | Missile warning, missile defense, and space domain awareness | Clear Space Force Station, Alaska | AN/FPS-132 Upgraded Early Warning Radar AN/FPS-108 Cobra Dane (Operating Location) Long Range Discrimination Radar | Operating Location: Eareckson Air Station, Alaska |
| Operating locations ||||||
| | Operating Location – Fylingdales | Missile warning and space domain awareness | RAF Fylingdales, United Kingdom | AN/FPS-132 Upgraded Early Warning Radar | |

## List of commanders

| No. | Commander | Commander | Term | Term | Term | Ref |
| No. | Portrait | Name | Took office | Left office | Duration | Ref |
| 1 | | Bourquin, Richard L.Colonel Richard L. Bourquin | 24 July 2020 | 15 July 2021 | 356 days | |
| 2 | | Cruz, Miguel A.Colonel Miguel A. Cruz | 15 July 2021 | 21 July 2023 | 2 years, 6 days | |
| 3 | | Schmitt, Ernest R.Colonel Ernest R. Schmitt | 21 July 2023 | Incumbent | 1 year, 238 days | |