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Funding: This study was supported by urgency funding from the U.K.’s Science and Technology Facilities Council (STFC) as part of the project “Curation and Preliminary Examination of the Winchcombe Carbonaceous Chondrite Fall.” Additional work was funded by STFC through grants ST/N000846/1, ST/T002328/1, ST/T506096/1, and ST/W001128/1 (to L.D., M.R.L., and L.J.Ha.); ST/V000675/1 (to K.H.J. and R.H.J.); ST/P005225/1 (to R.T.); ST/S000348/1 (to M.V.G., P.J.W., and M.J.B.); ST/R00143X/1 (to J.B. and L.J.Hi.); ST/S000615/1 (to G.S.C.); ST/V000799/1 (to P.G.); and ST/V000888/1 (to T.E.). A.J.K. and H.C.B. acknowledge funding support from UK Research and Innovation (UKRI) grant MR/T020261/1. P.L.C. acknowledges funding support from UKRI grant MR/S03465X/1. K.H.J. acknowledges funding support from the Royal Society, grant URF\R\201009. L.J.Ha. and M.R.L. acknowledge funding from Natural Environment Research Council (NERC) National Environmental Isotope Facility (NEIF) grant no. 2406.0321. L.D., M.R.L., and L.J.Ha. acknowledge COVID-19 funding support from the University of Glasgow, UK. D.V. was supported in part by NASA cooperative agreement 80NSSC21M0073. P.P. and I.Sy. acknowledge funding from the VEGA agency, project no.1/0421/20. A.J.T.J. acknowledges support from the European Union and the State of Hungary, cofinanced by the European Regional Development Fund in the project of GINOP-2.3.2-15-2016-00009 “ICER.” P.M.S. acknowledges support from the European Union’s Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement no. 945298. FRIPON was initiated by funding from ANR (grant N.13-BS05-0009-03), carried out by the Paris Observatory, Muséum National d’Histoire Naturelle, Paris-Saclay University, and Institut Pythéas (LAM-CEREGE). FRIPON data are hosted and processed at Institut Pythéas SIP (Service Informatique Pythéas). The Desert Fireball Network team and Global Fireball Observatory are funded by the Australian Research Council (DP200102073). Direct links between carbonaceous chondrites and their parent bodies in the solar system are rare. The Winchcombe meteorite is the most accurately recorded carbonaceous chondrite fall. Its pre-atmospheric orbit and cosmic-ray exposure age confirm that it arrived on Earth shortly after ejection from a primitive asteroid. Recovered only hours after falling, the composition of the Winchcombe meteorite is largely unmodified by the terrestrial environment. It contains abundant hydrated silicates formed during fluid-rock reactions, and carbon- and nitrogen-bearing organic matter including soluble protein amino acids. The near-pristine hydrogen isotopic composition of the Winchcombe meteorite is comparable to the terrestrial hydrosphere, providing further evidence that volatile-rich carbonaceous asteroids played an important role in the origin of Earth's water. Publisher PDF

MASCOT is a small asteroid lander launched on December 3rd, 2014, aboard the Japanese HAYABUSA2 asteroid sample-return mission towards the 980 m diameter C-type near-Earth asteroid (162173) 1999 JU3. MASCOT carries four full-scale asteroid science instruments and an uprighting and relocation device within a shoebox-sized 10 kg spacecraft; a complete lander comparable in mass and volume to a medium-sized science instrument on interplanetary missions. Asteroid surface science will be obtained by: MicrOmega, a hyperspectral near- to mid-infrared soil microscope provided by IAS; MASCAM, a wide-angle Si CMOS camera with multicolour LED illumination unit; MARA, a multichannel thermal infrared surface radiometer; the magnetometer, MASMAG, provided by the Technical University of Braunschweig. Further information on the conditions at or near the lander‘s surfaces is generated as a byproduct of attitude sensors and other system sensors. MASCOT uses a highly integrated, ultra-lightweight truss-frame structure made from a CFRP-foam sandwich. It has three internal mechanisms: a preload release mechanism, to release the structural preload applied for launch across the separation mechanism interface; a separation mechanism, to realize the ejection of MASCOT from the semi-recessed stowed position within HAYABUSA2; and the mobility mechanism, for uprighting and hopping. MASCOT uses semi-passive thermal control with Multi-Layer Insulation, two heatpipes and a radiator for heat rejection during operational phases, and heaters for thermal control of the battery and the main electronics during cruise. MASCOT is powered by a primary battery during its on-asteroid operational phase, but supplied by HAYABUSA2 during cruise for check-out and calibration operations as well as thermal control. All housekeeping and scientific data is transmitted to Earth via a relay link with the HAYABUSA2 main-spacecraft, also during cruise operations. The link uses redundant omnidirectional UHF-Band transceivers and patch antennae on the lander. The MASCOT On-Board Computer is a redundant system providing data storage, instrument interfacing, command and data handling, as well as autonomous surface operation functions. Knowledge of the lander’s attitude on the asteroid is key to the success of its uprighting and hopping function. The attitude is determined by a threefold set of sensors: optical distance sensors, photo electric cells and thermal sensors. A range of experimental sensors is also carried. MASCOT was build by the German Aerospace Center, DLR, with contributions from the French space agency, CNES. The system design, science instruments, and operational concept of MASCOT will be presented, with sidenotes on the development of the mission and its integration with HAYABUSA2.

The Mobile Asteroid Surface Scout (MASCOT) is a small landing package build by the German Aerospace Center (DLR) jointly with the French Space Agency (CNES). MASCOT will fly onboard the Japanese space probe Hayabusa-II, built by the Japan Aerospace Exploration Agency (JAXA) and is scheduled to be launched in late 2014 on a 5-year sample return mission to the Near-Earth Asteroid 1999 JU3. The lander is equipped with four science instruments which will take detailed close-up pictures and make a variety of in-situ measurements. MASCOT has a cubic shape roughly 29 cm x 27,5 cm x 20 cm and weighs about 10 kg. An internal mechanism with an eccentric tappet can be used to reorient MASCOT if needed and relocate to a different site to increase its investigation area. After the arrival and a characterization of the asteroid, MASCOT will be dropped from the Hayabusa-II mothership and will land passively on the asteroid surface. Before starting science measurements MASCOT must lie on the correct side. The attitude determination system consists of 2 types of sensors: solar cell based sun sensors on each side of MASCOT as well as 5 optical proximity sensors (OPS). The latter consists of an LED and a photodiode which can detect the reflected LED light when MASCOT is in proximity to the surface. A histogram filter is used for attitude determination and multi sensor data fusion. It is a bayesian filter used to estimate states which can be divided in a finite number of possible values. This is useful for MASCOT since all that is needed is an estimation of the side on which it is lying. This paper focuses on the attitude determination system of MASCOT. It describes the attitude determination sensors and the details of the filter algorithm. It also presents simulation results for system verification, as well as planned Monte-Carlo simulation and Hardware-in-the-Loop tests.

第14回宇宙科学シンポジウム (2014年1月9日-10日. 宇宙航空研究開発機構宇宙科学研究所(JAXA)(ISAS)相模原キャンパス), 相模原市, 神奈川県, 14ｔh Space Science Symposium (January 9-10, 2014. Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency(JAXA)(ISAS)Sagamihara Campus), Sagamihara, Kanagawa Japan, 著者人数: 19名, 資料番号: SA6000058152, レポート番号: P2-120

MASCOT, a small 10kg Asteroid landing package on-board Hayabusa-2 is currently finalizing Phase-C of its development and after official go-ahead during the Critical Design Review it will undergo a final verification program at DLR before send to JAXA to be integrated into the mother spacecraft. Its last stages during the Assembly, Integration and Verification (AIV) process show that by applying a unique mix of conventional and tailored Model Philosophies it is possible to dynamical adapt the test program, limited by a fixed launch date, to accomplish for the shortest planning and a suitable weighing of costs and risks. In addition, this paper introduces the term Concurrent AIV to express the many simultaneous running test and verification activities.

The mission scenario AsteroidSQUADS/iSSB was developed in response to several of the Recommendations from the 1st IAA Planetary Defense Conference which addressed the need for deflection-related testing and campaign design, studies of momentum transfer in impulsive deflection techniques, and the development of protocols and responsibilities within existing space situational awareness and civil defence infrastructures on a global scale. Several more recommendations put dangerous objects smaller than the current threshold definition for Potentially Hazardous Objects (PHO) in focus. Throughout, the need for increased international participation was emphasized. AsteroidSQUADS/iSSB is intended to enable Serendipitous Quantitative Understanding and Assessment of Deflection Strategies. The advantages and efficiency of modern small-satellite-derived design philosophies evolved and improved for interplanetary spaceflight are highlighted by using the DLR Kompaktsatellit programme's Standard Satellite Bus kit as a study baseline. This spacecraft platform draws strongly on the experiences gained and lessons learned from the DLR small satellites BIRD and TET. It also has been the baseline of choice in many studies at DLR's Bremen Concurrent Engineering Facility, and it is currently used for the AsteroidFinder spacecraft under development. A number of circumstances in today's commercial and scientific spaceflight environment are on their own widely regarded as detrimental or unpleasant situations: For some time now, an uneasy struggle has developed between the test flight requirements of the heavy launch vehicle sector, related costs and risks, commercial and schedule pressures, public relations and insurance contracting concerns, and the choice and motivation of payloads for such development flights. Also, realistic testing in particular of geostationary payload launch vehicles carries a significant risk of polluting the most vital regions of Earth-orbital space with large targets that invite the escalation of space debris collisional cascading (Kessler syndrome). In the planetary science sector, it has always been difficult to obtain funding for missions towards less prestigious target objects in the solar system. For most such missions, target selection was severely constrained by the need to cover as many fields of science as possible within the given launch budget. Resulting spacecraft designs push the launcher performance limit and require gravity-assists from the nearest planets. Accordingly, rather small probes experience extended interplanetary cruise phases, causing high radiation doses on sensitive components and high operational cost. In planetary defence, with few exceptions, lesson-learning has so far been restricted to paper exercises. Though NEO surveys have generally made good progress given the resources assigned, even the basic methods of deflection are hardly explored beyond lab experiments. The AsteroidSQUADS/iSSB mission scenario seeks to benefit from several opportunities which are presented by these situations when their mere co-existence is turned into a synergetic advantage for all potential participants, including all branches of the planetary defence community. It employs a flotilla of simple multi-role spacecraft directed at a suitable sub-PHO size practice target for a brief but intense integrated deflection campaign exercise in real space.

The AsteroidFinder mission, the first mission in the DLR-Kompaktsatellit program, will help characterize the unknown Inner Earth Object population in terms of mass, size and distribution. The satellite shall operate for a period of one year, aiming to detect faint objects down to an apparent magnitude of 18.5 Vmag (under a sky background of 20.3 Vmag). The space segment of the AsteroidFinder mission consists of a small satellite with a mass between 150-200kg. The design of the AsteroidFinder satellite bus and instrument has been driven by a trade-off between conflicting performance parameters and shows that it is feasible to design a small satellite with high performance in terms of agility, stability and data volume to support a mission with a substantial scientific return. In order to achieve the required performance of the satellite, the satellite has been designed using a mixture between COTS hardware and own developments. The design method has implemented state-of-the-art engineering methods and has been based on tailoring of already existing standards. The AsteroidFinder project conducted the PDR in May 2011, and phase C/D is expected to be initiated before the end of 2011.

The design of small satellites requires a paradigm shift in the thinking of satellite designers as well as mission scientists, payload users, and programme management - in brief, everyone involved. In a conventional approach, spacecraft design evolves in a mostly linear fashion from mission requirements by well-defined procedures through a series of reviews into a design space that is essentially not limited by constraints other than programmatic. The mission defines a pallet of instruments, their needs then shape the spacecraft bus, and the integrated spacecraft is finally mated to a dedicated launch, to be placed into an orbit carefully custom-tailored by mission analysis and continuously trimmed by on-board propulsion. Components are manufactured to spec, one-off plus spares, and painstaking testing has to iron out the many space firsts and compromises made in an arduous and protracted design process. Small satellite design reverses this comfortable line of thinking. It begins with hard, and not just programmatic constraints on most of the essential parameters that define a satellite. Launch as a secondary payload is the choice, not just for budgetary reasons, but due to the lack of viable dedicated launchers. It requires a small stowed envelope and a tightly limited mass budget. This results in limited surface area for solar panels and radiators. Small project volume enables a high flight cadence which makes re-use of designs and components desirable and feasible, in a self-catalyzing cycle. Re-use and constraints force the system perspective on every participant in a quick succession of sometimes diverging but generally converging iterations that lends itself to the Concurrent Engineering approach. There is simply no space left in a small satellite project for boxes to think in. To exploit the technological convergence that has created powerful and miniaturized science instruments and satellite components, the DLR research and development programme has initiated the Kompaktsatellit line of development. It is intended to enable dedicated missions for science projects that would earlier have resulted in one full-scale scientific instrument among many sharing a ride on a large platform without the perspective of follow-on within an academic career lifetime. In an internal competition, the AsteroidFinder instrument dedicated to the search for small bodies orbiting the Sun interior to Earth’s orbit has been selected as the payload to fly first on a Kompaktsatellit. Alongside, the Standard Satellite Bus kit, /SSB, is being developed, based on extensive re-use of experience, concepts, and components of the DLR satellites BIRD and TET. It is designed to avoid the overhead carried by pre-defined standard bus concepts while allowing for seamless integration of the payload into an organic spacecraft design. Challenges encountered and solutions found across the subsystems of AsteroidFinder/SSB will be presented.

It is the purpose of this thesis to give an account of significant events in the founding and development of the school, now known as "Snow College", during the founding and maintenance by the Latter-day Saint Church. This study is confined to the forty-four years the institution was under the control of the Church of Jesus Christ of Latter-day Saints and deals largely with data of educational significance. the problem, thus, is the founding and the development of Snow College, while under the direction of L.D.S. Church