Vandenberg Tracking Station & Ellison Onizuka Satellite Operations Facility (21st Space Operations Squadron)

Vandenberg Tracking Station (VTS) or call sign “COOK” and the Ellison Onizuka Satellite Operations Facility (EOSOF) or call sign “DICE” are components of the 21st Space Operations Squadron, a unit of Space Delta 6, Space Operations Command, Schriever Space Force Base, Colorado. VTS is one of seven worldwide remote tracking stations (RTS); DICE is one of two operational control nodes in the Satellite Control Network (SCN). 


EOSOF is located directly on Vandenberg Space Force Base (VSFB) while VTS is located approximately ten miles North of the installation. VSFB is located on the California central coast, the home of Space Launch Delta 30.  VTS’ strategic location on the West Coast allows it to conduct pre-launch satellite compatibility testing to ensure reliable on-orbit operation of polar orbiting satellites, as well as final countdown and liftoff.


VTS was established in 1959 originally as the 6596th Instrumentation Squadron under the Air Research and Development Command to become one of the first of seven remote RTS’ that comprise the Satellite Control Network (SCN).  After several reorganizations/redesignations, in 2020 the 21st Space Operations Squadron was assigned under Delta 6, Space Operations Command, United States Space Force.

EOSOF was the result of the 2001 base realignment and closure (BRAC) that directed the closure of Onizuka Air Force Station and relocation of its mission to Vandenberg Space Force Base. In 2010 21 SOPS Vandenberg Space Force Base was activated and later that same year Onizuka Air Force Station (aka Blue Cube) was closed.

COOK and DICE Overview

21 SOPS is comprised of both the VTS and EOSOF operational sites that are tenant units on VSFB.  VTS’ mission is to execute on-demand, real-time C2 operations for launch and operations of DoD, allied, and civil satellites providing assured access to space.  VTS supports DoD-assigned space missions by operating and maintaining SCN antennas providing data and status to multiple users and command centers. Additionally, the unit also supports other DoD systems providing critical capabilities in support of the Joint Force in the INDOPACOM region.

VTS also maintains the back-up scheduling Network Operation Center for 22nd SOPS and back-up satellite operations facilities for 2nd and 4th SOPS at VSFB. Additionally, 21 SOPS hosts the 148th SOPS (California Air National Guard) as a tenant at the VTS.  VTS is a three-sided station comprised of a 13-meter (A-side) Remote Block Change (RBC) antenna, a 46-foot (B-side) hybridized antenna, and 23-foot (D-side) Automated Remote Tracking Station (ARTS) transportable antenna.  Lastly, in 2018 VTS-A was upgraded to an RBC Hybrid.

DICE is one of two operational control nodes (OCNs) providing critical communication links encompassing TT&C data and secure voice between SCN remote tracking stations, mission users and command centers through VSFB. 

Organization Overview

The squadron as part of the $6.8 billion SCN directs day-to-day operations and mission support functions for all its units in INDOPACOM.  SCN consists of three ground systems the Automated Remote Tracking Station (ARTS), Remote Block Change (RBC), and Hybrid RBC antennas.

The squadron consists of five military members, 20 government civilians and approximately 35 contractors located at VTS and EOSOF.  In 2023 the majority of personnel relocated from EOSOF to VTS. Squadron personnel conduct various responsibilities to include support command/support staff, Mission Assurance and OCN monitoring/management.

Additionally, the squadron has three detachments located in the INDOPACOM region: Detachment 1 (Diego RTS), Detachment 2 (Guam RTS), and Detachment 3 (Hawaii RTS). Together they operate 11 SCN ARTS, RBC and Hybridized RBC antennas executing the 24/7 mission enabling real-time satellite C2 in support of the warfighter. 


21 SOPS, COOK SCN Systems

Antenna                                 Transmit                                Receive                        Built

COOK-A, RBC                       1.75 to 1.85 GHz                    2.2 to 2.3 GHz                2004

COOK-B, RBC Hybrid          1.75 to 1.85 GHZ                    2.2 to 2.3 GHZ                 1973

COOK-D, ARTS                    1.75 to 1.85 GHZ                    2.2 to 2.3 GHZ                   1993


Key Personnel

Commander                                                    Lt Col Matthew Knepper

Executive Director                                          Mr. Stephen Ramirez

Director of Operations                                    Maj Amanda Chivers

Senior Enlisted Leader                                   MSgt Alina Hanson

Mission Assurance Officer                             Mr. Christopher Babauta


(Current as of February 2024)