MSX Midcourse Space Experiment

Status of the BMDO Midcourse Space Experiment
24 April 1996
12:00 Noon

At 8:27 AM EST the Midcourse Space Experiment (MSX) spacecraft was launched by a Delta rocket from Vandenberg Air Force Base, CA into a nominal circular orbit with an altitude of 908 km and an inclination of 99.6 degrees. The spacecraft separated from the booster at approximately 9:26 AM in the proper attitude, solar panels were extended, and full solar power was attained. The spacecraft is stable at the proper attitude and all spacecraft systems, including the tape recorder, are operating normally. The experiment sequence has been initiated and instrument turn-on and checkout will continue throughout the day. At this time, all indications are that this mission has been an unqualified success.

MSX represents the first system demonstration in space of technology to identify and track ballistic missiles during their midcourse flight phase. The Sensor Technology Directorate of BMDO has overall responsibility of MSX. The Johns Hopkins University Applied Physics Laboratory (JHU/APL) serves as systems engineer and technical advisor. JHU/APL developed, integrated, tested, launched and is operating the MSX spacecraft and several of its primary sensors. It is noted that the MSX sensors are the first hyperspectral imagers flown in space and provide essential capabilities in identifying global change gases, including ozone and carbon dioxide, with capabilities heretofore unavailable in any currently flying or planned systems.

This page is in progress, please excuse misspellings and incompleteness.

The Midcourse Space Experiment (MSX) observatory is a Ballistic Missile Defense Organization project which offers major benefits for both the defense and civilian sectors. With a solid heritage in the successful Delta series, MSX represents the first system demonstration in space of technology to track ballistic missiles during the midcourse flight phase. The spacecraft features an advanced multispectral image capability to gather data on test targets and space background phenomena. MSX will aid future spacecraft design by monitoring on-orbit contamination of optical instruments. In addition, its investigation of the composition of Earth's atmosphere promises increased understanding of the environment.
Gene Heyler has produced a QuickTime movie of the MSX Spacecraft in action.

Program Management

The Sensor Technology Directorate(DTS) of the Ballistic Missile Defense Organization(BMDO) has overall responsibility for MSX. The Johns Hopkins University Applied Physics Laboratory(JHU/APL) serves as the system engineer and technical advisor. JHU/APL is under contract to BMDO to develop, integrate, test, launch, and operate the MSX spacecraft and several of its primary sensors.

Why MSX?

Designers of future operational space and ground-based surveillance and tracking systems require simultaneous, wideband optical data on midcourse missile flight, the trajectory phase between burnout and rentry. The precision MSX platform will collect that data over a wide-wavelength range during its long-duration mission, building on previous short-term SDI tests. MSX experiments will provide critical first-time observations of missile target signatures against Earth-limb, auroral, and celestial cluttered backgrounds.

Mission Design

MSX is to be launched aboard a Delta II booster from Vandenberg Air Force Base in California. Insertion altitude is approximately 900km, in a high-inclination, circular, near-sun synchronous orbit. Mission design lifetime is 4 years, with the SPIRIT III infrared telescope limited by coolant supply to 18-20 months of operation. Approximately 50% of MSX's weight and power is allocated to instrument use. During its primary mission, or "cryogen" phase, MSX is designed to gather data on backgrounds and to detect and track test-ICBMs launched from the Western Test Range(WTR) and targeted at the Kwajalein Missile Range in the Pacific. Other targets include IRBMs launched from Barking Sands in Hawaii, satellites, and objects deployed from MSX itself. The "post-cryogen" phase will focus on the celestial and terrestrial backgrounds, surveillance demonstrations, and contamination and environmental research.

Spacecraft Design

The 2,700-kg, 510-cm long MSX spacecraft includes three major sections, each with a 150-cm by 150cm cross section:

The versatile electronics section features a state-of-the-art attitude control, power, and command and telemetry systems including rotatable solar arrays, nickel/hydrogen battery power, steerable X-band antennas, and 108-Gbit data storage. The reaction wheel-driven attitude control systems achieves real-time pointing accuracy of better than 0.1 degrees and postprocessing knowledge of 9 micro-radians. Line-of-sight jitter is held to +/-9 micro-radians over instrument integration durations of approximately 1 second. MSX will operate in the background data gathering mode an average of 20 minutes per orbit, with target tracking tests lating 35 minutes. The system provides a "parked" safe mode for thermal recovery, cryogen conservation, and battery recharge between test cycles.
The mid-section graphite epoxy truss supports the large cryogenic dewar, which contains frozen hydrogen at approximately 8.5 K. The thermal design of the midsection maintains the outer shell of the dewar at approximately 200 K. The 200-cm-long truss thermally isolates the heat-sensitive instrument section from the much warmer spacecraft bus.
The instrument section houses 11 optical sensors, which are precisely aligned so target activity can be viewed simultaneously by multiple sensors. MSX is capable of observations at a wide range of infrared, visible and ultraviolet wavelengths from 110 nano-meters to 28 micro-meters.

Primary Instruments