The Netherlands has expertise in providing the instrumentation that transforms a satellite into a mission. From idea to creation, Dutch scientists and engineers combine experience with optics, sensors, mechanics and electronics to create an ideal environment for (inter)national collaboration in creating satellite instrumentation. HIFI, onboard the Herschel Space Observatory, was most recently launched and Earth observation instrument TROPOMI is currently at the heart of future instrument development.
Optics
TROPOMI Immersed Grating - image: TNO
The Netherlands has a long, rich history in the field of optics, beginning with Christiaan Huygens and his Traité de La Lumiére in 1690. One of the Netherlands’ greatest physicists and a telescope (device) builder, he founded the theory of the propagation of light. More recently the Delft University of Technology pioneered the field of electron optics, resulting in the development of the electron microscope. To this day amazing optical research is being carried out in optics in theNetherlands. Having such amazing history at hand is extremely beneficial to the Netherlands’ space industry due to the increasingly high-level optical requirements for Space missions. The recently launched Herschel Space Observatory uses more than 100 mirrors at the core of SRON’s HIFI instrument whose optical design and fabrication was led by the Netherlands. Inventive optical solutions have also been at the heart of the Netherlands’ success in optical Earth observation. Instruments like GOME, GOME 2, OMI and Sciamachy and even future atmospheric spectrometer TROPOMI would not have been possible without top of the line Dutch optical research including SRON’s immersed grating technology that makes TROPOMI’s huge advance in atmospheric spectrometry possible.
Mechanics
Herschel HIFI - image: SRONMechanical engineering was key to Herschel HIFI, for which the SME company Mecon was responsible for the mechanical assembly. Absolute perfection was required in order to ensure that the more than 100 mirrors built at ambient temperature on the ground now interact at nearly absolute zero in space with nano-meter accuracy. Mechanical assembly for other Dutch instruments like Sciamachy, OMI and GOME has also been consistently provided by Mecon.
ESA’s Gaia 3D star-mapper mission was only possible because of optical advances at Dutch research organisation TNO in polishing and using Silicon Carbide (SiC), an extremely specialized material, without which the nanometer accuracy required for the mission’s success could not have been achieved. The use of SiC required significant advances in optical polishing capabilities, but also in mechanical design and construction. Gaia’s entire meter long optical bench has to be made from a single piece of SiC in order to prevent shattering of the brittle optically optimal material.
Sensors
Hot Electron Bolometer Mixer spiral antenna - image: SRONThe Dutch also develop world class technology with in-house expertise and facilities to design, manufacture and optimize sensors. For instance, SRON’s Imaging X-ray Micro-Calorimeter Arrays for X-ray astronomy will create a giant leap in X-ray spectroscopy from astronomical sources. Developed over the last 20 years in partnership with (inter)national companies and organisations, it is truly impressive due to its amazing spectral resolution, high detection efficiency and accurate imaging capabilities. Another novel concept from SRON, the Hot Electron Bolometer is a new type of detector for sub millimetre radiation and far infrared. These highly sensitive radiation detectors function at extremely low temperatures of 0.1 degrees above absolute zero and have been specifically developed for use in a new generation of far-infrared space telescopes. A telescope with this technology onboard would be sensitive enough to measure radiation from the darkest corners of the universe or see very cool gas clouds wherein stars and planetary systems form.
Electronics
Lightweight Radar Breadboard - image: TNOThe Netherlands is also at the forefront of electronics research for future missions. Dutch scientists at Cosine provide small, light structures with low power consumption; the key to success for electronic instrumentation in space applications. Lighter payloads reduce the mission costs and allow us to put more instruments into the confined space of a small satellite. Another huge step forward in instrument efficiency is on-board calculation. The System-on-Chip (SoC) approach offers a small, light, single-chip solution to fit each instrument’s requirements. Future planetary missions will require advanced, smart, low resource payloads using SoC to enable the exploration of the solar system in a more frequent, timely and multi-purpose manner. TNO has created Monolithic Microwave Integrated Circuits (MMIC's) that integrate many discrete communications components into a single “Core Integrated Circuit," significantly reducing the number of components within a T/R module, as well as the size of the module. SRON and TNO are also partnering to develop new antenna-detector solutions for the sub-mm wave frequency range used by SPICA's SAFARI (SPICA FAR Infrared) instrument in 2017. Planar Circular Symmetric Electromagnetic Band Gap (PCS-EBG) structures, developed by TNO for high-performance planar antennas, can be used to enhance the efficiency, bandwidth, directivity and polarisation purity of very low cost and low profile printed antennas and arrays.
