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Historical Projects

Since MSSL was established in 1966, we have participated in over 35 satellite missions and over 200 rocket experiments.

Examples of some previous successful projects are shown below:

Cassini ELS Spectrometer in the MSSL calibration chamber

Professor Andrew Coates led the MSSL team that produced the Electron Spectrometer (ELS) for NASA’s Cassini mission. Microchannel plate detectors and high voltage power supplies were provided by the Rutherford-Appleton Laboratory while the Norwegian Defence Research Establishment produced the sensor management unit electronics. MSSL designed the ELS hemispherical analyser and overall instrument housing, along with the amplifier electronics.

The instrument was integrated at MSSL and then subjected to a rigorous test campaign, including calibration in MSSL’s low energy plasma calibration system. ELS was launched on board Cassini in 1997 and following a seven-year cruise phase, Cassini reached Saturn in 2004. ELS has provided almost continuous data since then, from over 70 revolutions of Saturn and over 50 close flybys of Titan and Saturn’s icy satellites.

MSSL has continued to lead the ELS team throughout the operations phase of the mission. A data processing pipeline takes the raw data and produces calibrated data products, which are then supplied to the science team for analysis.

Mechnical engineer, John Coker, inspects SPIRE before its cold vibration test at CSL in Belgium

SPIRE, the Spectral and Photometric Imaging Receiver, is a submillimetre camera and spectrometer for the European Space Agency’s Herschel Space Observatory. It comprises a three-band imaging photometer operating at 250, 360 and 520 mm, and an imaging Fourier Transform Spectrometer (FTS) covering 200-670 mm. MSSL were responsible for the design, manufacture and integration of the structure, the 2 Kelvin thermal straps and the 300 milli-Kelvin busbar.

The major engineering requirements for SPIRE fabrication at MSSL were:

• Different temperature zones (12 K, 4.5K, 1.75 K, 0.3 K) and instrument thermally isolated from Herschel

• Inside the instrument detector boxes thermally isolated from main structure

• Inside the detector box the detectors thermally isolated from box

• RF Insulation (<10 GHz)

• All main thermal bus-bars electrically isolated

• Main structure electrically isolated from Herschel/Spacecraft

• Optical Alignment and straylight

• Stiff and Strong enough (+50 kg instrument)

Cluster PEACE instrument

Launched in the summer of 2000, Cluster II is part of the Solar Terrestrial Science Programme Cornerstone (together with SOHO) of ESA's Horizon 2000 programme. The quartet of Cluster spacecraft orbit the Earth exploring the magnetosphere and solar wind close to Earth.

Each Cluster spacecraft has a suite of instruments to study the waves, fields and particles in the magnetosphere. Part of that suite is the PEACE instruments. Two PEACE sensors on each spacecraft measure the 3D velocity distributions of the electrons that make up part of the space plasma surrounding the Earth.

The PEACE instrument was designed and built by MSSL, who are also responsible for the operation of the instruments and the processing and calibration of the raw instrument data. Prof. Andrew Fazakerley is the instrument's Principal Investigator.

PEACE is a top-hat electrostatic electron analyser. It is designed to measure the 3D electron velocity distribution in the energy range 0.7 eV to 32 keV in the vicinity of the Cluster spacecraft. This energy range covers the majority of the plasma observed outside the inner magnetosphere (where plasma is energised to energies in excess of 1 MeV).

Swift UVOT in the MSSL cleanroom

The Swift Gamma Ray Burst Explorer carries three instruments to enable the most detailed observations of gamma ray bursts to date, the X-Ray Telescope (XRT), the UV/Optical Telescope (UVOT) and the Burst Alert Telescope (BAT).

The UVOT makes Swift a complete multi-wavelength facility. Co-aligned with the XRT, UVOT provides simultaneous ultraviolet and optical coverage (170-650 nm) in a 17' x 17' field. Despite its limited aperture, UVOT represents a powerful complement to the other instruments because of its UV capabilities and the absence of atmospheric extinction, diffraction and background. Since UVOT has photon counting detectors, which are able to retain individual photon positions and timing information, it operates in a mode more similar to typical x-ray telescopes than to typical optical telescopes.

The largest part of  the Swift UltraViolet/Optical Telescope (UVOT), the two metre long Telescope Module (TM), was designed and built by MSSL.

The Telescope Module consists of four sections:
• the external baffle, which reduces the stray light inside the telescope
• the telescope, which contains the primary and secondary mirrors
• the detector module, which houses the rest of the optical system and its associated electronics
• the power supply module, on which is mounted the power supply unit for the TM and the external connector panel

The 600mm integrating sphere

MSSL provided the in flight Calibration Assembly (CAA) for the Near Infrared Specrometer (NIRSpec) on the James Webb Space Telescope (JWST), the successor to the Hubble Space Telescope. In addition to the CAA, MSSL also provided the ground base calibration equipment, namely the Shack Hartmann Detector system (SHD), to align the NIRSpec optics during instrument integration and the Calibration Light Sources (CLS) for calibration of the complete instrument. 

Due to the required low levels of background infrared radiation the complete CLS had to be cooled to liquid Nitrogen temperatures (77K -196C).  Operating the sources and mechanisms at these temperatures held many challenges. The 600mm integrating sphere that simulates the JWST optics is shown here.  A Lightbox, mounted on the sphere chamber, supplied different types of light using filters and attenuators. Supporting bespoke electronics racks and user interface software developed at MSSL enabled control of the system.

The systems have now all been delivered to the ESA contractor in Germany.

Page last modified on 06 sep 11 15:27