Space projects in development

The Space Nuclear Power programme at The University of Leicester has been operating for over a decade. In this time, a number of different radioisotope power systems (RPS) have been developed which can provide thermal and electrical power to future space missions.

RPS use the heat generated from the decay of radioisotope materials such as Plutonium and Americium. Plutonium-238 has historically been used to fuel RPS that have powered Mars rovers and missions to the Outer Solar System and beyond. However, Americium-241 is the radioisotope of choice in Europe, and the University is leading the development of RPS technologies that will use Americium-241. Americium-241 provides a near-constant power supply for many decades which is of particular benefit to long duration missions. University researchers are working with the National Nuclear Laboratory to transform the required Americium-241 into a useable form. NNL reprocesses/recycles the Americium-241 from civil nuclear waste. Engineers and Scientists at the University have designed the cladding, insulation, and housing for the fuel to ensure it can be handled safely, and survive a range of mission failure scenarios.

The smallest RPS that the team are working on is a Radioisotope Heater Unit (RHU). The RHU is small enough to hold in one hand and can be used to heat spacecraft components for a number of years, which is especially important for missions destined for icy moons or deep space. The Radioisotope Thermoelectric Generator (RTG) is much larger and weighs around 10kg. The RTG provides heat to thermoelectrics which converts thermal power to electrical power. The University researchers are collaborating with industry partners to make lightweight and efficient, low-cost thermoelectrics. RTGs are used to power spacecraft subsystems and recharge batteries when there's limited sunlight.

The RHU and RTG development has been funded by the European Space Agency as part of the ENDURE programme. The first flight opportunity for this technology will be a RHU on the ESA Rosalind Franklin Mars rover mission, providing critical heat to the lander that will then deploy Europe's first Mars rover.

The x-ray optics group have been working on multiple X-ray telescope missions since the 1960s. Initially working on Micro-Channel Plate (MCP) detectors, proportional counters and traditional Wolter instruments for sounding rocket experiments and The Einstein Observatory (HEAO 2). With the world class expertise and knowledge gained in MCP detectors and the 1979 paper by J Angel suggesting novel X-ray telescope designs, the group started to investigate imaging optics based on the production of MCPs. The group produced the very first x-ray image from such an optic and proved the possibility of these novel optics. They became known as Micro Pore Optics (MPOs) in order to differentiate them from MCPs.

The first leader of the group was Professor George Fraser who was instrumental in designing and furthering the use of MPOs for X-ray telescope missions. By tessellating multiple MPOs over a metal frame, it is possible to produce a large field of view optic which would work in a similar way to lobster’s eyes. The first mission to be selected to use a lobster eye telescope was the European Space Agency's (ESA) BepiColombo mission to Mercury. The Mercury Imaging X-ray Spectrometer (MIXS) was the first telescope to use MPOs and created two separate channels by using the optics in one case in a Wolter approximation and the other as a large field of view collimator.

Since BepiColombo (launched October 2018), several missions have been proposed and built using MPOs as their basis. The missions the group has been involved in include; Einstein Probe (launched January 2024), SVOM (due for launch mid-2024), SMILE (due for launch mid-2025) and THESEUS (Phase A study), along with several other proposals. The x-ray optics group has been at the forefront of the research in to these optics since their conception and are known as world experts in this area.

SMILE (Solar wind Magnetosphere Ionosphere Link Explorer) is a joint ESA (European Space Agency) and Chinese Academy of Sciences (CAS) mission to study the interaction of the solar wind with the Earth’s magnetosphere and ionosphere. The SMILE S/C (Spacecraft) payload consists of four instruments; SXI (Soft X-ray Imager), UVI (Ultraviolet Imager), LIA (Light Ion Analyser) and MAG (Magnetometer).

The University of Leicester is the PI (Principal Investigator) institution for the SXI instrument. SXI is a collaboration between three UK institutions (University of Leicester, Mullard Space Science Laboratory and the Open University) funded by the United Kingdom Space Agency (UKSA) and several European and international organisations.

SXI will investigate the dynamic interaction of the solar wind with the Earth’s magnetosphere by the detection of X-rays produced when heavy ions in the solar wind collide with neutral particles within the Earth’s exosphere. This mechanism allows the position of the boundary between the outer solar wind and the inner Earth’s magnetosphere to be tracked using global X-ray imaging. Simultaneous to the SXI measurements will be observations of the aurorae at the North Pole taken with the UVI Instrument. The LIA and MAG instruments complement these measurements by monitoring the in-situ plasma and magnetic field environments. The mission science is intended to assist the understanding of the structures and dynamics of the magnetosphere and ionosphere on a global scale, with many downstream benefits and terrestrial applications. The S/C has a highly elliptical Earth orbit, travelling from about 5,000km at perigee to 120,000km at apogee. Approximately 80% of the 52-hour orbital period is spent obtaining high altitude observations.

The design of SXI utilises years of heritage in novel light-weight micropore X-ray optics to focus X-rays on to a pair of CCD (Charge-coupled Device) detectors within a compact telescope. Notable engineering challenges for the Instrument include the sole use of European parts for all systems, cryogenic TCS (Thermal Control System) and the inclusion of a radiation shutter mechanism which is opened and closed to protect the CCDs as the S/C traverses the Van Allen Belts.

The University of Leicester has recently completed structural, thermal, electrical and functional testing of the Proto-flight Model (PFM) SXI, and is on track to deliver the Instrument to ESA in Q1 of 2024. The instruments are then integrated on to the PLM (Payload Module) at Airbus Madrid. The SMILE S/C integration and test will take place at ESTEC (The European Space Research and Technology Centre) and launch from Kourou mid-2025.

The “Mars Magnetosphere ATmosphere Ionosphere and Space-weather SciencE (M-MATISSE)” mission is an European Space Agency (ESA) Medium class (M7) candidate currently in Phase A study by ESA.

M-MATISSE’s main scientific goal is to unravel the complex and dynamic couplings of the Martian magnetosphere, ionosphere and thermosphere (MIT coupling) with relation to the solar wind (i.e. space weather) and the lower atmosphere. It will provide the first global characterisation of the dynamics of the Martian system at all altitudes, to understand how the atmosphere dissipates the incoming energy from the solar wind, including radiation, as well as how different surface processes are affected by space weather activity.

It will consist of two orbiters with focused, tailored, high-heritage payloads that will observe the plasma environment from the surface to space through coordinated simultaneous observations, named Henri and Marguerite in honour of the French artist Henri Matisse and his daughter. It will utilize a unique multi-point vantage point observational perspective, with the combination of in-situ measurements by both orbiters and remote observations of the lower atmosphere and ionosphere by radio crosstalk between them.

Dr Beatriz Sánchez–Cano from the University of Leicester is leading the overall mission as well as acting as Principal Investigators for the Mars Ensemble of Particle Instruments (M-EPI) and the Science Data Centre for mission coordination, planning and science exploitation.

M-MATISSE is the product of a large organized and experienced international consortium. It has the unique capability to track solar perturbations from the solar wind down to the surface, being the first mission fully dedicated to understand planetary space weather at Mars. It will revolutionize our understanding and ability to forecast potential global hazard situations at Mars, an essential precursor to any future robotic and human exploration.

The “Transient High Energy Sky and Early Universe Surveyor” (THESEUS) mission concept is an European Space Agency candidate in Phase A study as part of the ESA Medium class call. M7 will be the seventh, medium-sized mission of the ESA long-term science programme under the Voyage 2050 plan.

THESEUS aims to fully exploit the unique and breakthrough potentialities of Gamma-Ray Bursts (GRBs) for investigating the Early Universe and substantially advancing Multi-Messenger Astrophysics. THESEUS will discover these events, which are the most powerful explosive phenomena in the Universe over the entirety of cosmic history and allow detailed tests of fundamental physics. THESEUS will also characterise the electromagnetic counterparts to gravitational-wave events, providing unique multi-wavelength capability from gamma-rays to the near-infrared, transforming multi-messenger astronomy in the 2030s.

THESEUS will carry three instruments on a robotic, fast-response satellite, including the Soft X-ray Imager (SXI) which will be led from the UK by the University of Leicester. The SXI provides a revolutionary wide-field X-ray imaging capability, monitoring very large areas of sky simultaneously looking for X-ray transients while performing a sky survey. The SXI optics are based on technology developed at Leicester for ESA’s BepiColombo mission to Mercury and the France/China SVOM mission, while the focal plane will utilise newly developed large CMOS detectors provding fast-readout and sensitivity.

The SXI will be developed by a European consortium, including scientists from the UK, Germany, Spain, Belgium, Czech Republic, Poland and a wider international science team.

Professor Paul O’Brien from the University of Leicester, Principal Investigator for the SXI has said: “The capability of THESEUS will revolutionize time domain and multi-messenger astronomy, one of the fastest growing areas of astrophysics. The UK is a key part of the mission, providing a sensitive, wide-field X-ray telescope funded by UKSA in the UK and other European agencies.”