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  • 1.
    Bazzocchi, Michael C. F.
    et al.
    Institute for Aerospace Studies, University of Toronto.
    Emami, Reza
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Institute for Aerospace Studies, University of Toronto.
    Formation of Multiple Landers for Asteroid Detumbling2018In: Advances in Space Research, ISSN 0273-1177, E-ISSN 1879-1948, Vol. 62, no 3, p. 732-744Article in journal (Refereed)
    Abstract [en]

    This work develops a method for ascertaining the landing locations and thruster orientations of a formation of multiple spacecraft on an irregular asteroid for discrete time optimal detumbling control, as a prerequisite to asteroid redirection. Asteroid geometries are known to be extremely irregular, especially for small asteroids, which are the typical targets for redirection missions. The method entails the modelling of asteroids as convex polyhedra with triangular facets, and computing the mass and inertial properties through the divergence theorem and Green’s theorem. Given the asteroid geometry, mass, and inertial properties, the feasible lander locations and thruster orientations are determined. The model ensures full attitude control of the asteroid, using multiple spacecraft with fixed-orientation, low-thrust modules, through measures imposed on the location and orientation of each thruster. A linear control scheme is employed to assess the time and fuel requirements of the asteroid detumbling maneuver, given feasible spacecraft formation configurations and thruster orientations. The method then assesses the detumbling time performance of each formation configuration to determine the discrete optimal landed formation configuration for a given asteroid. Simulations are performed to demonstrate the method using an irregular asteroid with characteristics derived from available asteroid data. Extensions of the method are further discussed in light of the results.

  • 2.
    Felicetti, Leonard
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Emami, Reza
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Attitude Coordination of Multiple Spacecraft for Space Debris Surveillance2017In: Advances in Space Research, ISSN 0273-1177, E-ISSN 1879-1948, Vol. 59, no 5, p. 1270-1288Article in journal (Refereed)
    Abstract [en]

    This paper discusses the attitude coordination of a formation of multiple spacecraft for space debris surveillance. Off-the-shelf optical sensors and reaction wheels, with limited field of view and control torque, respectively, are considered to be used onboard the spacecraft for performing the required attitude maneuvers to detect and track space debris. The sequence of attitude commands are planned by a proposed algorithm, which allows for a dynamic team formation, as well as performing suitable maneuvers to eventually point towards the same debris. A control scheme based on the nonlinear state dependent Riccati equation is designed and applied to the space debris surveillance mission scenario, and its performance is compared with those of the classic linear quadratic regulator and quaternion feedback proportional derivative controllers. The viability and performance of the coordination algorithm and the controllers are validated through numerical simulations.

  • 3.
    Felicetti, Leonard
    et al.
    Dipartimento di Ingegneria Astronautica Elettrica Ed Energetica (DIAEE).
    Piergentili, Fabrizio
    Dipartimento di Ingegneria Meccanica e Aeronautica (DIMA), University of Rome la Sapienza.
    Santoni, Fabio
    Università di Roma la Sapienza, Dipartimento di Ingegneria Astronautica Elettrica Ed Energetica (DIAEE).
    Thermosphere density and wind measurements in the equatorial region using a constellation of drag balance nanospacecraft2014In: Advances in Space Research, ISSN 0273-1177, E-ISSN 1879-1948, Vol. 54, no 3, p. 546-553Article in journal (Refereed)
    Abstract [en]

    A mission for in situ thermosphere density and winds measurement is described, based on nanospacecraft equipped with a drag balance instrument (DBI) and a GPS receiver. The mission is based on nanosatellite clusters deployed in three orbital planes. In this study, clusters of 10 nanospacecraft are considered, leading to a mission based on a total of 30 nanospacecraft. The geometry analyzed is a symmetrical one, including an equatorial orbit and two orbits with the same inclination and opposing ascending nodes. The main idea is that, by combining the accurate information on the satellite inertial position and velocity provided by the GPS receiver and the drag acceleration intensity provided by the DBI, due to the orbits' geometrical configuration, both atmospheric drag and wind can be resolved in a region close to the orbit nodes. Exploiting the Earth oblateness effect, a complete scan of the equatorial regions can be accomplished in the short mission lifetime typical of very low Earth orbit satellites, even in high solar activity peaks, when the expected nanospacecraft lifetime is about 40 days

  • 4.
    Felicetti, Leonard
    et al.
    Università di Roma la Sapienza, Dipartimento di Ingegneria Astronautica Elettrica Ed Energetica (DIAEE).
    Santoni, Fabio
    Università di Roma la Sapienza, Dipartimento di Ingegneria Astronautica Elettrica Ed Energetica (DIAEE), Università di Roma la Sapienza, Dipartimento di Ingegneria Astronautica Elettrica Ed Energetica (DIAEE).
    Drag balance Cubesat attitude motion effects on in-situ thermosphere density measurements2014In: Advances in Space Research, ISSN 0273-1177, E-ISSN 1879-1948, Vol. 54, no 3, p. 489-498Article in journal (Refereed)
    Abstract [en]

    The dynamics of Cubesats carrying a drag balance instrument (DBI) for in situ atmosphere density measurements is analyzed. Atmospheric drag force is measured by the displacement of two light plates exposed to the incoming particle flow. This system is well suited for a distributed sensor network in orbit, to get simultaneous in situ local (non orbit averaged) measurements in multiple positions and orbit heights, contributing to the development and validation of global atmosphere models. The implementation of the DBI leads to orbit normal pointing spinning two body system. The use of a spin-magnetic attitude control system is suggested, based only on magnetometer readings, contributing to making the system simple, inexpensive, and reliable. It is shown, by an averaging technique, that this system provides for orbit normal spin axis pointing. The effect of the coupling between the attitude dynamics and the DBI is evaluated, analyzing its frequency content and showing that no frequency components arise, affecting the DBI performance. The analysis is confirmed by Monte Carlo numerical simulation results

  • 5.
    Garg, Kanika
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Emami, Reza
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Balloon Ascent Prediction: Comparative Study of Analytical, Fuzzy and Regression Models2019In: Advances in Space Research, ISSN 0273-1177, E-ISSN 1879-1948, Vol. 64, no 1, p. 252-270Article in journal (Refereed)
    Abstract [en]

    The ascent prediction of high-altitude zero-pressure stratospheric balloons is an important aspect of targeted test flight. Prediction of the balloon ascent rate is the prerequisite for many of the flights as it helps in planning ballasting and valving manoeuvres. In this paper, a standard analytical model, a fuzzy model and a statistical regression model are developed and compared to predict the zero-pressure balloon ascent. The flight data is extracted from the Esrange balloon service system for zero-pressure balloons with different payload capability, and several potential explanatory variables are computed for every sampled climbed segment. For the fuzzy modelling approach, a fuzzy c-mean clustering algorithm is used for system identification and prediction. For the regression approach, a Gaussian process regression is used, and principal component analysis is applied for finding the significant inputs. The result shows that the data driven approaches are more efficient than the standard analytical model.

  • 6.
    Hakima, Houman
    et al.
    Institute for Aerospace Studies, University of Toronto .
    Bazzocchi, Michael C. F.
    Institute for Aerospace Studies, University of Toronto.
    Emami, Reza
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Institute for Aerospace Studies, University of Toronto.
    A Deorbiter CubeSat for Active Orbital Debris Removal2018In: Advances in Space Research, ISSN 0273-1177, E-ISSN 1879-1948, Vol. 61, no 9, p. 2377-2392Article in journal (Refereed)
    Abstract [en]

    This paper introduces a mission concept for active removal of orbital debris based on the utilization of the CubeSat form factor. The CubeSat is deployed from a carrier spacecraft, known as a mothership, and is equipped with orbital and attitude control actuators to attach to the target debris, stabilize its attitude, and subsequently move the debris to a lower orbit where atmospheric drag is high enough for the bodies to burn up. The mass and orbit altitude of debris objects that are within the realms of the CubeSat’s propulsion capabilities are identified. The attitude control schemes for the detumbling and deorbiting phases of the mission are specified. The objective of the deorbiting maneuver is to decrease the semi-major axis of the debris orbit, at the fastest rate, from its initial value to a final value of about 6,471 km (i.e., 100 km above Earth considering a circular orbit) via a continuous low-thrust orbital transfer. Two case studies are investigated to verify the performance of the deorbiter CubeSat during the detumbling and deorbiting phases of the mission. The baseline target debris used in the study are the decommissioned KOMPSAT-1 satellite and the Pegasus rocket body. The results show that the deorbiting times for the target debris are reduced significantly, from several decades to one or two years.

  • 7.
    Kloos, Jacob L.
    et al.
    Centre for Research in Earth and Space Sciences, York University, Earth and Space Sciences, Toronto.
    Moores, John E.
    York University, Toronto.
    Lemmon, Mark
    Texas A&M University, College Station.
    Kass, David
    Jet Propulsion Laboratory, California Institute of Technology, Pasadena.
    Francis, Raymond
    Jet Propulsion Laboratory/Caltech.
    Juarez, Manuel de la Torre
    Jet Propulsion Laboratory, California Institute of Technology, Pasadena.
    Zorzano, María Paz
    Centro de Astrobiología (CSIC-INTA), Madrid.
    Martin-Torres, Javier
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    The First Martian Year of Cloud Activity from Mars Science Laboratory (Sol 0 - 800)2016In: Advances in Space Research, ISSN 0273-1177, E-ISSN 1879-1948, Vol. 57, no 5, p. 1223-1240Article in journal (Refereed)
    Abstract [en]

    Using images from the Navigation Cameras onboard the Mars Science Laboratory rover Curiosity, atmospheric movies were created to monitor the cloud activity over Gale Crater. Over the course of the first 800 sols of the mission, 133 Zenith Movies and 152 Supra-Horizon Movies were acquired which use a mean frame subtraction technique to observe tenuous cloud movement. Moores et al. (2015a) reported on the first 360 sols of observations, representing LS = 150° to 5°, and found that movies up to LS = 184° showed visible cloud features with good contrast while subsequent movies were relatively featureless. With the extension of the observations to a full Martian year, more pronounced seasonal changes were observed. Within the Zenith Movie data set, clouds are observed primarily during LS = 3° - 170°, when the solar flux is diminished and the aphelion cloud belt is present at equatorial latitudes. Clouds observed in the Supra-Horizon Movie data set also exhibit seasonality, with clouds predominantly observed during LS = 72° - 108°. The seasonal occurrence of clouds detected in the atmospheric movies is well correlated with orbital observations of water-ice clouds at similar times from the MCS and MARCI instruments on the MRO spacecraft. The observed clouds are tenuous and on average only make up a few-hundredths of an optical depth, although more opaque clouds are observed in some of the movies. Additionally, estimates of the phase function calculated using water-ice opacity retrievals from MCS are provided to show how Martian clouds scatter sunlight, and thus provide insight into the types of ice crystals that comprise the clouds.

  • 8.
    Mendaza de Cal, Maria Teresa
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Blanco-Ávalos, J.J.
    Universidad Alcalá de Henares (UAH) Dpto. Física y Matemáticas, Campus Científico-Tecnológico (Externo) Alcalá de Henares (Madrid).
    Martin-Torres, Javier
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Instituto Andaluz de Ciencias de la Tierra (UGR-CSIC), Avenida de las Palmeras 4, Armilla, Granada, Spain.
    Interplanetary Coronal Mass Ejection effects on thermospheric density as inferred from International Space Station orbital data2017In: Advances in Space Research, ISSN 0273-1177, E-ISSN 1879-1948, Vol. 60, no 10, p. 2233-2251Article in journal (Refereed)
    Abstract [en]

    The solar activity induces long term and short term periodical variations in the dynamics and composition of Earth’s atmosphere. The Sun also shows non periodical (i.e., impulsive) activity that reaches the planets orbiting around it. In particular, Interplanetary Coronal Mass Ejections (ICMEs) reach Earth and interact with its magnetosphere and upper neutral atmosphere. Nevertheless, the interaction with the upper atmosphere is not well characterized because of the absence of regular and dedicated in situ measurements at high altitudes; thus, current descriptions of the thermosphere are based on semi empirical models.

    In this paper, we present the total neutral mass densities of the thermosphere retrieved from the orbital data of the International Space Station (ISS) using the General Perturbation Method, and we applied these densities to routinely compiled trajectories of the ISS in low Earth orbit (LEO). These data are explicitly independent of any atmospheric model. Our density values are consistent with atmospheric models, which demonstrates that our method is reliable for the inference of thermospheric density. We have inferred the thermospheric total neutral density response to impulsive solar activity forcing from 2001 to the end of 2006 and determined how solar events affect this response. Our results reveal that the ISS orbital parameters can be used to infer the thermospheric density and analyze solar effects on the thermosphere.

  • 9.
    Moores, John E.
    et al.
    York University, Toronto.
    Lemmon, Mark T.
    Texas A&M University, College Station.
    Rafkin, Scot C R
    Southwest Research Institute, San Antonio, Texas.
    Francis, Raymond
    University of Western Ontario.
    Pla-Garcia, Jorge
    Centro de Astrobiologia, INTA-CSIC, Madrid.
    Juárez, Manuel De La Torre
    Jet Propulsion Laboratory, California Institute of Technology, Pasadena.
    Bean, Keri
    Texas A&M University.
    Kass, David
    Jet Propulsion Laboratory, California Institute of Technology, Pasadena.
    Haberle, Robert
    Ames Research Centre.
    Newman, Claire .E.
    Ashima Research, Pasadena.
    Mischna, Michael A.
    Jet Propulsion Laboratory, California Institute of Technology, Pasadena.
    Vasavada, Ashwin R.
    Jet Propulsion Laboratory, California Institute of Technology, Pasadena.
    Rennó, Nilton
    University of Michigan.
    Bell, Jim
    Arizona State University.
    III, Fred .J. Calef
    Jet Propulsion Laboratory, California Institute of Technology, Pasadena.
    Cantor, Bruce
    Malin Space Science Systems.
    McConnochie, Timothy H.
    Department of Astronomy, University of Maryland, College Park.
    Harri, Ari-Matti
    Finnish Meteorological Institute.
    Genzer, Maria
    Finnish Meteorological Institute.
    Wong, Michael
    University of Michigan.
    Smith, Michael D.
    NASA Goddard Space Flight Center.
    Martin-Torres, Javier
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Zorzano, María-Paz
    Centro de Astrobiologia, INTA-CSIC, Madrid , Instituto Nacional de Técnica Aeroespacial, Madrid.
    Kemppainen, Osku
    Finnish Meteorological Institute.
    McCullough, Emily
    University of Western Ontario.
    Atmospheric movies acquired at the Mars Science Laboratory landing site: Cloud Morphology, Frequency and Significance to the Gale Crater Water Cycle and Phoenix Mission Results2015In: Advances in Space Research, ISSN 0273-1177, E-ISSN 1879-1948, Vol. 55, no 9, p. 2217-2238Article in journal (Refereed)
    Abstract [en]

    We report on the first 360 sols (LS 150° to 5°), representing just over half a Martian year, of atmospheric monitoring movies acquired using the NavCam imager from the Mars Science Laboratory (MSL) Rover Curiosity. Such movies reveal faint clouds that are difficult to discern in single images. The data set acquired was divided into two different classifications depending upon the orientation and intent of the observation. Up to sol 360, 73 Zenith Movies and 79 Supra-Horizon Movies have been acquired and time-variable features could be discerned in 25 of each. The data set from MSL is compared to similar observations made by the Surface Stereo Imager (SSI) onboard the Phoenix Lander and suggests a much drier environment at Gale Crater (4.6°S) during this season than was observed in Green Valley (68.2°N) as would be expected based on latitude and the global water cycle. The optical depth of the variable component of clouds seen in images with features are up to 0.047 ± 0.009 with a granularity to the features observed which averages 3.8 degrees. MCS also observes clouds during the same period of comparable optical depth at 30 and 50 km that would suggest a cloud spacing of 2.0 to 3.3 km. Multiple motions visible in atmospheric movies support the presence of two distinct layers of clouds. At Gale Crater, these clouds are likely caused by atmospheric waves given the regular spacing of features observed in many Zenith movies and decreased spacing towards the horizon in sunset movies consistent with clouds forming at a constant elevation. Reanalysis of Phoenix data in the light of the NavCam equatorial dataset suggests that clouds may have been more frequent in the earlier portion of the Phoenix mission than was previously thought.

  • 10.
    Pomares, Jorge
    et al.
    University of Alicante.
    Felicetti, Leonard
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Pérez, Javier
    University of Alicante.
    Emami, Reza
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Space Mechatronics group, University of Toronto, Institute for Aerospace Studies.
    Concurrent Image-based Visual Servoing with Adaptive Zooming for Non-cooperative Rendezvous Maneuvers2018In: Advances in Space Research, ISSN 0273-1177, E-ISSN 1879-1948, Vol. 61, no 3, p. 862-878Article in journal (Refereed)
    Abstract [en]

    An image-based servo controller for the guidance of a spacecraft during non-cooperative rendezvous is presented in this paper. The controller directly utilizes the visual features from image frames of a target spacecraft for computing both attitude and orbital maneuvers concurrently. The utilization of adaptive optics, such as zooming cameras, is also addressed through developing an invariant-image servo controller. The controller allows for performing rendezvous maneuvers independently from the adjustments of the camera focal length, improving the performance and versatility of maneuvers. The stability of the proposed control scheme is proven analytically in the invariant space, and its viability is explored through numerical simulations.

  • 11.
    Sadeghi, Soheil
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Emami, Reza
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Institute for Aerospace Studies, University of Toronto.
    Electric potential structures of auroral acceleration region border from multi-spacecraft Cluster data2018In: Advances in Space Research, ISSN 0273-1177, E-ISSN 1879-1948, Vol. 61, no 8, p. 2050-2056Article in journal (Refereed)
    Abstract [en]

    This paper studies an auroral event using data from three spacecraft of the Cluster mission, one inside and two at the poleward edge of the bottom of the Auroral Acceleration Region (AAR). The study reveals the three-dimensional profile of the region’s poleward boundary, showing spatial segmentation of the electric potential structures and their decay in time. It also depicts localized magnetic field variations and field-aligned currents that appear to have remained stable for at least 80 s. Such observations became possible due to the fortuitous motion of the three spacecraft nearly parallel to each other and tangential to the AAR edge, so that the differences and variations can be seen when the spacecraft enter and exit the segmentations, hence revealing their position with respect to the AAR.

  • 12.
    Sadeghi, Soheil
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Emami, Reza
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Institute for Aerospace Studies, University of Toronto, Toronto, Canada.
    Large-scale Altitude Distribution Profile of Auroral Parallel Electric Potentials: A Statistical Analysis of Cluster Data2019In: Advances in Space Research, ISSN 0273-1177, E-ISSN 1879-1948, Vol. 64, no 2, p. 378-384Article in journal (Refereed)
    Abstract [en]

    It is generally believed that the heart of the Auroral Acceleration Region (AAR) is located between 5000 and 8000 km altitude above the auroral oval. Various altitude distribution profiles are suggested by different theories, including the transition layer model, which predicts that the strongest electric fields can be found at about 1 RE, and can vary depending on the plasma and geomagnetic conditions. However, there have been no specific experimental results that cover regions both below and well above such altitude. This paper presents a method for obtaining such a profile from AAR satellite crossings, applies it to a data set gathered from 116 Cluster spacecraft encounters with acceleration potential structures, and discusses the results. The crossings cover an altitude range between 0.63 RE and 2.9 RE. The outcome is the first empirical altitude distribution profile of the auroral acceleration potentials. The results suggest that the region within the altitude range of 0.9245 RE and 1.158 RE statistically contains 30% of the total potential, which is the largest fraction of the parallel potentials among all altitude segments of the same size. The altitude which equally divides the distribution of acceleration potentials was found at 1.076 RE (6863 km). The obtained parallel potential distribution is in agreement with both the magnetic mirror force theory and the transition layer model, and can hence provide a proper baseline for future missions to the AAR.

  • 13.
    Sadeghi, Soheil
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Emami, Reza
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Multi-spacecraft Studies of the Auroral Acceleration Region: From Cluster to Nanosatellites2017In: Advances in Space Research, ISSN 0273-1177, E-ISSN 1879-1948, Vol. 59, no 5, p. 1173-1188Article in journal (Refereed)
    Abstract [en]

    This paper discusses the utilization of multiple Cubesats in various formations for studies in the auroral acceleration region. The focus is on the quasi-static properties, spatio-temporal features, electric potential structures, field-aligned currents, and their relationships, all of which are fundamentally important for an understanding of the magnetosphere-ionosphere coupling. It is argued that a multitude of nanosatellites can address some of the relevant outstanding questions in a broader range of spatial, temporal, and geometrical features, with higher redundancy and data consistency, potentially resulting in a shorter mission period and a higher chance of mission success. A number of mission concepts consisting of a cluster of 6 to 12 Cubesats with their specific onboard payloads are suggested for such missions over a period of as short as two months.

  • 14.
    Torppa, Johanna
    et al.
    Space Systems Finland.
    Granvik, Mikael
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Department of Physics, University of Helsinki.
    Penttilä, Antti
    Department of Physics, University of Helsinki.
    Reitmaa, Jukka
    Space Systems Finland.
    Tudose, Violeta
    Space Systems Finland.
    Pelttari, Leena
    Space Systems Finland.
    Muinonen, Karri
    Department of Physics, University of Helsinki.
    Bakker, Jorgo
    European Space Astronomy Center.
    Navarro, Vicente
    European Space Astronomy Center.
    O’Mullane, William
    European Space Astronomy Center.
    Added-value interfaces to asteroid photometric and spectroscopic data in the Gaia database2018In: Advances in Space Research, ISSN 0273-1177, E-ISSN 1879-1948, Vol. 62, no 2, p. 464-476Article in journal (Refereed)
    Abstract [en]

    We present two added-value interfaces (AVIs) for analyzing photometric and spectroscopic data observed by the Gaia satellite. The Gaia Added-Value Interface for Temporal Analysis (GAVITEA) is used to calculate an estimate for the spin state and shape of an asteroid from its photometric data, and the Gaia Added-Value Interface for Spectral Classification (GAVISC) provides tools to define the taxonomic type and surface absorption coefficient based on spectroscopic asteroid data. Computations are mainly carried out using well-known methods of asteroid data analysis but the AVIs also offer the possibility to test novel methods that are specifically developed for analyzing temporally sparse photometric data, typical for Gaia.

  • 15.
    Watermann, Jürgen F.
    et al.
    Le Studium and LPC2E/CNRS.
    Gleisner, Hans
    Danish Meteorological Institute.
    Rasmussen, Thorkild Maack
    Geological Survey of Denmark and Greenland.
    A geomagnetic activity forecast for improving the efficiency of aeromagnetic surveys in Greenland2011In: Advances in Space Research, ISSN 0273-1177, E-ISSN 1879-1948, Vol. 47, no 12, p. 2172-2181Article in journal (Refereed)
    Abstract [en]

    In recent years several aeromagnetic surveys were carried out in Greenland and more will be carried out in the future. We describe some of the characteristics pertinent to surveys in Greenland and the problems faced and experiences made by the survey teams working there, with special emphasis on the west coast where most surveys were conducted. Both unfavorable terrestrial weather and space weather appear to complicate survey planning. We discuss possible options available to the survey teams for mitigating the adverse effect of part of the problems, namely survey data contamination by intense geomagnetic activity. The implementation of a prototype geomagnetic activity forecast service as an aid to planning survey flights is discussed in more detail. The forecast service was tested by an independent observer, and the performance of the scheme is evaluated by a subsequent comparison between forecast and actual measurements. The comparison rendered largely acceptable results, but their validity is limited by the fact that the two-month test interval was characterized by a mostly relatively quiet magnetic field

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