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Chang’E−4 lunar explorer is the backup of the Chang’E−3, which is composed of a communication relay satellite, a lander and a rover, it is estimated that the Chang’E−4 explorer will be launched by the end of 2018, which is scheduled to land at the south pole Aitken Basin, and carry out the in situ detection and reconnaissance at the far side of the moon with the communication support of the relay satellite. Chang’E−4 mission has been planned to install six kinds of scientific payloads to complete the corresponding tasks, three kinds of payloads on the lander are the Landing Camera (LCAM), the Terrain Camera (TCAM), and the Low Frequency Spectrometer (LFS), and three kinds of payloads on the rover are the Panoramic Camera (PCAM), the Lunar Penetrating Radar (LPR), and the Visible and Near-Infrared Imaging Spectrometer (VNIS). The LFS is newly developed for Chang’E−4 lander, and other five kinds of payloads are the inherited instruments from Chang’E−3. Besides the above six payloads, there are also three international joint collaboration payloads to be installed on the Chang’E−4 explorer, which are the Lunar Lander Neutrons and Dosimetry(LND) installed on the lander, the Advanced Small Analyzer for Neutrals(ASAN) installed on the rover, Netherlands-China Low-Frequency Explorer (NCLE) installed on the relay satellite. The paper mainly discusses the Chang’E−4's scientific objectives, landing area overview, payloads configuration and system design, and the task for each payload with its main technology index.

In this paper, we propose an architecture for lunar in-situ resource utilization (ISRU) which can provide propellant, typically cryogenic hydrogen and oxygen, to a cislunar aggregation point in support of future space missions to the Moon, Mars, and beyond at a price competitive with commercial delivery from Earth. This architecture is premised on maximizing the non-linear scaling laws of key system components: the ISRU plant, the nuclear reactor, and the reusable lunar lander. Engineering and cost models were developed to evaluate the impact of non-linear scaling laws on a reference architecture. The scaling laws applicable to each key system component were evaluated and incorporated in our model. We also provide sensitivity analysis showing how the model is impacted by commercial delivery costs to the cislunar aggregation point. This study showed that the cost of propellant sourced from lunar ISRU production can be lower than that delivered from Earth when maximal scale is utilized in sizing the key system components.

The lunar surface is continuously exposed to the micrometeoroid environment. Hypervelocity impacts of interplanetary dust particles with speeds around 17 km s − 1 generate secondary ejecta on the lunar surface. A dust detector placed on the moon is capable of characterizing the secondary ejecta population. The purpose of this paper is to study the speed and trajectory information of ejecta by impact simulations and its implications for the location of a dust sensor on the surface. AUTODYN15.0/2D software was used to simulate the velocity and angular distributions of ejecta created by the primary impacts of interplanetary dust particles. We considered projectiles with sizes of 10 μ m spheres in diameter with speeds of 17 km s − 1 . We used impact angles of 15°, 30°, 45°, 60°, 75°, and 90° with respect to the surface. A significant percentage of the impact ejecta are created in the early-time stage of the impact process. This population can be captured by a sensor placed on the lunar surface (e.g. Lunar Ejecta and Meteorites (LEAM) experiment) or by a sensor mounted directly on a lander (e.g. Lunar Dust eXplorer (LDX)). The secondary ejecta population above the lunar surface is considered to explain the results of the LEAM experiment. A sensor directly placed on the surface like LEAM is not very well suited to measure the high-speed ejecta component – a sensor located at a few meters height (e.g. on top of a lunar lander) would measure higher fluxes.

During a stay on the moon humans are exposed to elevated radiation levels due to the lack of substantial atmospheric and magnetic shielding compared to the Earth's surface. The absence of magnetic and atmospheric shielding allows cosmic rays of all energies to impinge on the lunar surface. Beside the continuous exposure to galactic cosmic rays (GCR), which increases the risk of cancer mortality, exposure through particles emitted in sudden nonpredictable solar particle events (SPE) may occur. SPEs show an enormous variability in particle flux and energy spectra and have the potential to expose space crew to life threatening doses. On Earth, the contribution to the annual terrestrial dose of natural ionizing radiation of 2.4 mSv by cosmic radiation is about 1/6, whereas the annual exposure caused by GCR on the lunar surface is roughly 380 mSv (solar minimum) and 110 mSv (solar maximum). The analysis of worst case scenarios has indicated that SPE may lead to an exposure of about 1 Sv. The only efficient measure to reduce radiation exposure is the provision of radiation shelters. Measurements on the lunar surface performed during the Apollo missions cover only a small energy band for thermal neutrons and are not sufficient to estimate the exposure. Very recently some data were added by the Radiation Dose Monitoring (RADOM) instrument operated during the Indian Chandrayaan Mission and the Cosmic Ray Telescope (CRaTER) instrument of the NASA LRO (Lunar Reconnaisance Orbiter) mission. These measurements need to be complemented by surface measurements. Models and simulations that exist describe the approximate radiation exposure in space and on the lunar surface. The knowledge on the radiation exposure at the lunar surface is exclusively based on calculations applying radiation transport codes in combination with environmental models. Own calculations are presented using Monte-Carlo simulations to calculate the radiation environment on the moon and organ doses on the surface of the moon for an astronaut in an EVA suit and are compared with measurements. Since it is necessary to verify/validate such calculations with measurement on the lunar surface, a description is given of a radiation detector for future detailed surface measurements. This device is proposed for the ESA Lunar Lander Mission and is capable to characterize the radiation field concerning particle fluencies, dose rates and energy transfer spectra for ionizing particles and to measure the dose contribution of secondary neutrons.

A major concern for long-term deep space missions is the detrimental impact of cosmic radiation on human health. Especially the presence of high-energy particles of high atomic mass (HZE) represents a serious threat. To contribute to a fundamental understanding of space radiation effects and to help improving risk assessment for humans on the Moon, the ESA Lunar Lander mission model payload includes a package dedicated to cell-based radiobiology experiments in the form of an Autonomous Microscope for Examination of Radiation Effects (AMERE). The purpose of this setup is to enable real-time visualization of DNA damage repair in living cells after traversal of HZE particles on the Moon. To assess the feasibility of this challenging experiment, we have analysed the biological and technological demands. In this article, we discuss the experimental concept, the biological considerations and describe the implications for system design.

In late 2010, the DLR Space Administration invited the German industry to submit a proposal for a study about a Mobile Payload Element (MPE), which could be a German national contribution to the ESA Lunar Lander Mission. Several spots in the south polar region of the moon come into consideration as landing site for this mission. All possible spots provide sustained periods of solar illumination, interrupted by darkness periods of several 10 h. The MPE is outlined to be a small, autonomous, innovative vehicle in the 10 kg class for scouting and sampling the environment in the vicinity of the lunar landing site. The novel capabilities of the MPE will be to acquire samples of lunar regolith from surface, subsurface as well as shadowed locations, define their geological context and bring them back to the lander. This will enable access to samples that are not contaminated by the lander descent propulsion system plumes to increase the chances of detecting any indigenous lunar volatiles contained within the samples. Kayser-Threde, as prime industrial contractor for Phase 0/A, has assembled for this study a team of German partners with relevant industrial and institutional competence in space robotics and lunar science. The primary scientific objective of the MPE is to acquire clearly documented samples and to bring them to the lander for analysis with the onboard Lunar Dust Analysis Package (L-DAP) and Lunar Volatile Resources Analysis Package (L-VRAP). Due to the unstable nature of volatiles, which are of particular scientific interest, the MPE design needs to provide a safe storage and transportation of the samples to the lander. The proposed MPE rover concept has a four-wheeled chassis configuration with active suspension, being a compromise between innovation and mass efficiency. The suspension chosen allows a compact stowage of the MPE on the lander as well as precise alignment of the solar generators and instruments. Since therefore no further complex mechanics are necessary, the active suspension significantly contributes to the lightweight MPE design. The thermal control system enables the MPE to operate in shaded areas for about 2 h and hibernate darkness periods of about 14 h. Increasing the hibernation capability requires additional battery capacity and thus increases the MPE mass. As operational modes teleoperations from earth and autonomous navigation are foreseen. The MPE payload includes navigation cameras, a close-up imager and a mole as sampling device. The MPE phase 0/A study finished in early 2012. This article describes the resulting MPE rover concept with focus on its scientific benefit for the Lunar Lander Mission.

A scientific camera system would provide valuable geological context from the surface for lunar lander missions. Here, we describe the PanCam instrument from the ESA ExoMars rover and its possible adaptation for the proposed ESA lunar lander. The scientific objectives of the ESA ExoMars rover are designed to answer several key questions in the search for life on Mars. The ExoMars PanCam instrument will set the geological and morphological context for that mission. We describe the PanCam scientific objectives in geology, and atmospheric science, and 3D vision objectives. We also describe the design of PanCam, which includes a stereo pair of Wide Angle Cameras (WACs), each of which has a filter wheel, and a High Resolution Camera for close up investigations. The cameras are housed in an optical bench (OB) and electrical interface is provided via the PanCam Interface Unit (PIU). Additional hardware items include a PanCam Calibration Target (PCT). We also briefly discuss some PanCam testing during field trials. In addition, we examine how such a ‘Lunar PanCam’ could be adapted for use on the Lunar surface on the proposed ESA lunar lander.

The Lunar Volatile Resources Analysis Package (L-VRAP) has been conceived to deliver some of the objectives of the proposed Lunar Lander mission currently being studied by the European Space Agency. The purpose of the mission is to demonstrate and develop capability; the impetus is very much driven by a desire to lay the foundations for future human exploration of the Moon. Thus, L-VRAP has design goals that consider lunar volatiles from the perspective of both their innate scientific interest and also their potential for in situ utilisation as a resource. The device is a dual mass spectrometer system and is capable of meeting the requirements of the mission with respect to detection, quantification and characterisation of volatiles. Through the use of appropriate sampling techniques, volatiles from either the regolith or atmosphere (exosphere) can be analysed. Furthermore, since L-VRAP has the capacity to determine isotopic compositions, it should be possible for the instrument to determine the sources of the volatiles that are found on the Moon (be they lunar per se, extra-lunar, or contaminants imparted by the mission itself).