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N. V. Emelyanov - One of the best experts on this subject based on the ideXlab platform.
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Natural Satellites mutual phenomena observations: Achievements and future
Planetary and Space Science, 2019Co-Authors: Jean-eudes Arlot, N. V. EmelyanovAbstract:Abstract Astrometry of Solar system objects needs to perform observations regularly since the motions are fast and the dynamical models need sample of data on long intervals of time. The goal of this paper is to show that some phenomena occurring during the equinox on the giant planets are worth to be observed. Past experience has shown the interest of such observations which should be continued in the future due to their relevant contribution to improve the dynamical models. Using the best ephemerides of the Natural planetary Satellites, we calculate the next phenomena to occur in order to prepare the future observational campaigns. We provide in this paper the tables of the dates of the next phenomena as their observational conditions which depends on the opposition and the declination of the planet. Past observations provided particularly accurate data, better than all the other ground based observations and we encourage observations in the next future especially for planetary systems for which no space mission is planned.
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Dynamics of Natural Satellites of Planets Based on Observations
Astronomy Reports, 2018Co-Authors: N. V. EmelyanovAbstract:There is wide interest in the results of studies of the dynamics of Satellites of planets. Such data are needed to determine the physical properties of celestial bodies, and they may be able to provide information about the origins and evolution of the solar system. The general approach to studying the dynamics of Satellites involves developing models for the motion and ephemerides based on observational data. Ephemerides are required to prepare and launch space missions to other planets and help discover new celestial bodies. High-precision astrometric coordinates of the principal Satellites of Jupiter, Saturn, and Uranus are derived from photometric observations of occultations and eclipses of these Satellites. To this end, worldwide observing campaigns have been organized. Enhancement in the precision of ephemerides can be obtained not only by increasing the accuracy of observations, but also by expanding the time interval covered by the observations. Many new, distant Satellites of the major planets were discovered in the early 21st century. However, observations of these Satellites are scarce and were obtained over short time intervals; as a result, some of these Satellites were lost. To date, 179 Natural Satellites are known. This paper is based on a presentation made at the conference “Modern Astrometry 2017,” dedicated to the memory of K.V. Kuimov (Sternberg Astronomical Institute, Moscow State University, October 23–25, 2017).
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Astrometric results of observations at Russian observatories of mutual occultations and eclipses of Jupiter’s Galilean Satellites in 2009
Solar System Research, 2011Co-Authors: N. V. Emelyanov, S. N. Vashkov'yak, A. V. Devyatkin, D. L. Gorshanov, Maksim V. Andreev, A. A. Berezhnoi, A. S. Bekhteva, Yu. I. Velikodskii, I. A. Vereshchagina, I. S. IzmailovAbstract:In 2009, in five Russian observatories photometric observations of Jupiter’s Galilean Satellites during their mutual occultations and eclipses were carried out. Based on these observations, an original method was used to ascertain astrometric results such as the difference between the coordinates of pairs of Satellites. Fifty-three phenomena were successfully observed. A total of 94 light curves of Satellites were measured. The error in the coordinates of Satellites due to random errors in photometry, calculated on all data obtained, was 0.041″ in right ascension and 0.046″ in declination. The discrepancies between the theory and observations in these coordinates was found to be 0.060″ and 0.057″, respectively. The results were uploaded to the common database for all observations of Natural Satellites of planets at the Natural Satellites Data Center (NSDC), which is available online at http://www.sai.msu.ru/neb/nss/index.htm. For the first time in the practice of photometric observations of Satellites in epochs of mutual occultations and eclipses a new method of observation was tested, which eliminates from astrometric results the major systematic errors caused by an inaccurate account of the background level. The tests were conducted in the Terskol Observatory and the observatory of the Crimean laboratory of the Sternberg State Astronomical Institute of the Moscow State University. The application of the new method showed that the elimination of the background level at these observatories was carried out correctly.
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The NSDB Natural Satellites astrometric database
Astronomy & Astrophysics, 2009Co-Authors: J.-e. Arlot, N. V. EmelyanovAbstract:Context. Any study of the dynamics of the Natural Planetary Satellites needs to gather as many astrometric observations as possible of those that have been observed for centuries. This kind of work is partially made by each astronomer starting this kind of study but has never been done for all the satellite systems. Aims. The goal of our work is to build a database of all the available astrometric observations, together with all the information needed for efficient use of these data, and to avoid astronomers interested in the dynamics of Planetary Satellites have to redo this data search. Methods. To do this we had to find and carefully read all the publications including observational data, international journals, or internal reports to be able to add the observations in the database knowing the reference frame used by the observer, the corrections and reduction made, and the time scale needed to link all the data. We also had to contact observatories and observers to be sure to have the raw data available. We gathered the bibliographic references related to the observations put in the database. Results. A new database containing about 90 percent of all the observations useful for studying the dynamics of the Satellites is now available for the interested community of astronomers. NSDB is accessible on the Internet: http://www.imcce.fr/nsdc (IMCCE) and http://lnfm1.sai.msu.ru/neb/nss/nssnsdcme.htm (trilingual version of SAI).
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The Natural Satellites ephemerides facility MULTI-SAT
Astronomy & Astrophysics, 2008Co-Authors: N. V. Emelyanov, J.-e. ArlotAbstract:Context. There is a need in some research facilities for deriving ephemerides, controlling observations, verifying various models of motion, and calculating the coordinates in space of Natural planetary Satellites. Aims. The goal of our work is to elaborate the ephemerides of all Natural Satellites based upon all observations available to date and readily accessible for any user via the Internet. Methods. For all outer planetary Satellites, original numerical models of motion are used that are based on all published observations. For other Satellites, the theoretical models of the motion are taken from publications that are as recent as possible. Complete collection of the theories and models of motion is realized as a software for the ephemerides of Natural Satellites available on the web pages of the so-called server MULTI-SAT. Results. A new facility for producing ephemerides of all Natural Satellites of planets (except the Moon) has been created at IMCCE and SAI. Special features of the ephemerides are realized, such as predicting the phenomena and providing configurations useful for the observers. The server MULTI-SAT is accessible through the Internet. The URL addresses are http://www.imcce.fr/sat (English and French versions at IMCCE) and http://www.sai.msu.ru/neb/nss/index.htm (English, French, and Russian versions at SAI). This paper includes a complete review of the most precise theories of motion of all Natural Satellites that we used and an analysis of the precision of the proposed ephemerides.
J.-e. Arlot - One of the best experts on this subject based on the ideXlab platform.
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mutual events between galilean Satellites observed with sara 0 9 m and 0 6 m telescopes during 2014 2015
Monthly Notices of the Royal Astronomical Society, 2019Co-Authors: Xueguang Zhang, J.-e. ArlotAbstract:Observation of mutual events has been confirmed to be a most effective and accurate ground-based method for obtaining accurate astrometric data by fitting the flux variation of involved Satellites during the events, which is very invaluable for improving the orbital models of the Natural Satellites. The mutual events between the Galilean Satellites occur every six years. During the observational campaign of 2014-15, 21 mutual events between Galilean Satellites were observed with the SARA 0.9 m and 0.6 m telescopes. The model proposed by M. Assafin et al. (2009) and Zhang et al. (2011) for mutual occultation and Zhang et al. (2011) for mutual eclipse were used to fit the light curves, taking the Lommel-Seeliger scattering law (Surdej and Surdej, 1978) and the solar limb darkening into account. In this paper, the astrometric results of the Galilean Satellites from the mutual events we observed will be shown, such as the impact parameter and its corresponding mid-time, and the velocity of occulting/eclipsing satellite relative to the occulted/eclipsed one.
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A New Consortium: the European Satellite Partnership for Computing Ephemerides (ESPaCE)
2012Co-Authors: W. Thuillot, J.-e. Arlot, V. Lainey, Véronique Dehant, J. P. De Cuyper, Leonid Gurvits, Hauke Hussmann, J. Oberst, Pascal Rosenblatt, Jean-charles MartyAbstract:ESPaCE, the European Satellite PArtnership for Computing Ephemerides, is a new EC-FP7 program which aims at strengthening the collaborative activities in the domain of the development of ephemerides and reference systems for Natural Satellites and spacecraft. This program started in June 2011 for a 4 year duration. For this program, teams from seven European institutions (IMCCE, ROB, TUB, JIVE, DLR, CNES, TUD) convened to get benefit from their mutual expertises in order to reach a better knowledge of the dynamics and physics of Natural Satellites and of spacecraft motions. All the results and documents, in particular improved ephemerides, will be made available using standard formats (VO standard, SPICE kernels) for the use by space agencies, planetary scientists, or the public.
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The NSDB Natural Satellites astrometric database
Astronomy & Astrophysics, 2009Co-Authors: J.-e. Arlot, N. V. EmelyanovAbstract:Context. Any study of the dynamics of the Natural Planetary Satellites needs to gather as many astrometric observations as possible of those that have been observed for centuries. This kind of work is partially made by each astronomer starting this kind of study but has never been done for all the satellite systems. Aims. The goal of our work is to build a database of all the available astrometric observations, together with all the information needed for efficient use of these data, and to avoid astronomers interested in the dynamics of Planetary Satellites have to redo this data search. Methods. To do this we had to find and carefully read all the publications including observational data, international journals, or internal reports to be able to add the observations in the database knowing the reference frame used by the observer, the corrections and reduction made, and the time scale needed to link all the data. We also had to contact observatories and observers to be sure to have the raw data available. We gathered the bibliographic references related to the observations put in the database. Results. A new database containing about 90 percent of all the observations useful for studying the dynamics of the Satellites is now available for the interested community of astronomers. NSDB is accessible on the Internet: http://www.imcce.fr/nsdc (IMCCE) and http://lnfm1.sai.msu.ru/neb/nss/nssnsdcme.htm (trilingual version of SAI).
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Division I-III / Working Group Natural Planetary Satellites
Proceedings of the International Astronomical Union, 2008Co-Authors: J.-e. Arlot, Kaare Aksnes, Carlo Blanco, Nikolaj V. Emelianov, Robert A. Jacobson, G. A. Krasinsky, Jay H. Lieske, D. Pascu, Michel Rapaport, Mitsuru SomaAbstract:1. Activities of the Working Group on Natural Planetary Satellites The main goal of the Working Group was to gather astrometric observations made during the triennum as well as old observations not yet published in the data base. The WG encouraged the making of new observations. A Spring School was organized in China in order to teach the observational techniques of Natural Satellites to students and young astronomers. New theoretical models of the motion of the Satellites and fit of the current models to new observations were used in order to make ephemerides of all the planetary Satellites with tools useful for observations such as configurations. These ephemerides named MULTISAT are available at or at . Original ephemerides are also available on JPL’s Horizons ephemerides and on MPC ephemerides for irregular Satellites. A workshop has been held in Paris in November 2006 for organizing campaigns of observations. The problem of a standard format for the astrometric observations of the Natural Satellites raised and will have to be solved during the next triennum.
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division i iii working group Natural planetary Satellites
Transactions of the International Astronomical Union, 2008Co-Authors: J.-e. Arlot, R. A. Jacobson, Kaare Aksnes, Carlo Blanco, Nikolaj V. Emelianov, G. A. Krasinsky, Jay H. Lieske, D. Pascu, Michel Rapaport, Mitsuru SomaAbstract:1. Activities of the Working Group on Natural Planetary Satellites The main goal of the Working Group was to gather astrometric observations made during the triennum as well as old observations not yet published in the data base. The WG encouraged the making of new observations. A Spring School was organized in China in order to teach the observational techniques of Natural Satellites to students and young astronomers. New theoretical models of the motion of the Satellites and fit of the current models to new observations were used in order to make ephemerides of all the planetary Satellites with tools useful for observations such as configurations. These ephemerides named MULTISAT are available at or at . Original ephemerides are also available on JPL’s Horizons ephemerides and on MPC ephemerides for irregular Satellites. A workshop has been held in Paris in November 2006 for organizing campaigns of observations. The problem of a standard format for the astrometric observations of the Natural Satellites raised and will have to be solved during the next triennum.
B. Bolin - One of the best experts on this subject based on the ideXlab platform.
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detecting earth s temporarily captured Natural Satellites minimoons
Icarus, 2014Co-Authors: Peter Brown, B. Bolin, Robert Jedicke, Mikael Granvik, Ellen S. Howell, Michael C. Nolan, Peter Jenniskens, Monique Chyba, Geoff PattersonAbstract:Abstract We present a study on the discoverability of temporarily captured orbiters (TCOs) by present day or near-term anticipated ground-based and space-based facilities. TCOs (Granvik, M., Vaubaillon, J., Jedicke, R. [2012]. Icarus 218, 262–277) are potential targets for spacecraft rendezvous or human exploration (Chyba, M., Patterson, G., Picot, G., Granvik, M., Jedicke, R., Vaubaillon, J. [2014]. J. Indust. Manage. Optim. 10, 477–501) and provide an opportunity to study the population of the smallest asteroids in the Solar System. We find that present day ground-based optical surveys such as Pan-STARRS and ATLAS can discover the largest TCOs over years of operation. A targeted survey conducted with the Subaru telescope can discover TCOs in the 0.5–1.0 m diameter size range in about 5 nights of observing. Furthermore, we discuss the application of space-based infrared surveys, such as NEOWISE, and ground-based meteor detection systems such as CAMS, CAMO and ASGARD in discovering TCOs. These systems can detect TCOs but at a uninteresting rate. Finally, we discuss the application of bi-static radar at Arecibo and Green Bank to discover TCOs. Our radar simulations are strongly dependent on the rotation rate distribution of the smallest asteroids but with an optimistic distribution we find that these systems have >80% chance of detecting a >10 cm diameter TCO in about 40 h of operation.
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Detecting Earth’s temporarily-captured Natural Satellites—Minimoons
Icarus, 2014Co-Authors: B. Bolin, Peter Brown, Robert Jedicke, Mikael Granvik, Ellen S. Howell, Michael C. Nolan, Peter Jenniskens, Monique Chyba, Geoff Patterson, Richard J. WainscoatAbstract:Abstract We present a study on the discoverability of temporarily captured orbiters (TCOs) by present day or near-term anticipated ground-based and space-based facilities. TCOs (Granvik, M., Vaubaillon, J., Jedicke, R. [2012]. Icarus 218, 262–277) are potential targets for spacecraft rendezvous or human exploration (Chyba, M., Patterson, G., Picot, G., Granvik, M., Jedicke, R., Vaubaillon, J. [2014]. J. Indust. Manage. Optim. 10, 477–501) and provide an opportunity to study the population of the smallest asteroids in the Solar System. We find that present day ground-based optical surveys such as Pan-STARRS and ATLAS can discover the largest TCOs over years of operation. A targeted survey conducted with the Subaru telescope can discover TCOs in the 0.5–1.0 m diameter size range in about 5 nights of observing. Furthermore, we discuss the application of space-based infrared surveys, such as NEOWISE, and ground-based meteor detection systems such as CAMS, CAMO and ASGARD in discovering TCOs. These systems can detect TCOs but at a uninteresting rate. Finally, we discuss the application of bi-static radar at Arecibo and Green Bank to discover TCOs. Our radar simulations are strongly dependent on the rotation rate distribution of the smallest asteroids but with an optimistic distribution we find that these systems have >80% chance of detecting a >10 cm diameter TCO in about 40 h of operation.
Lucy A. Mcfadden - One of the best experts on this subject based on the ideXlab platform.
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vesta s missing moons comprehensive search for Natural Satellites of vesta by the dawn spacecraft
Icarus, 2015Co-Authors: Lucy A. Mcfadden, David R. Skillman, Nargess Memarsadeghi, Carol A. Polanskey, Marc D. Rayman, Mark V. Sykes, Pasquale Tricarico, S P Joy, E E Palmer, D P ObrienAbstract:Earth-bound searches for Natural Satellites of 4 Vesta have been reported since 1987. With use of technological advances and observing capability has come a reduction in the detectable size of a possible satellite. The Dawn mission brought a small camera close to Vesta itself. In our search, which was carried out with a comprehensive data acquisition strategy and by experienced searchers, we find no Satellites to a detection limit as small as 3-m radius. Various observation and analysis strategies are discussed in detail. It is now time to factor the null result of this search into the context of satellite formation among other main belt asteroids and to conduct dynamical modeling to explore the suspected forces contributing to the absence of Satellites at Vesta today.
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Vesta’s missing moons: Comprehensive search for Natural Satellites of Vesta by the Dawn spacecraft
Icarus, 2015Co-Authors: Lucy A. Mcfadden, David R. Skillman, Nargess Memarsadeghi, Steve Joy, Carol A. Polanskey, Marc D. Rayman, Mark V. Sykes, Pasquale Tricarico, Eric PalmerAbstract:Earth-bound searches for Natural Satellites of 4 Vesta have been reported since 1987. With use of technological advances and observing capability has come a reduction in the detectable size of a possible satellite. The Dawn mission brought a small camera close to Vesta itself. In our search, which was carried out with a comprehensive data acquisition strategy and by experienced searchers, we find no Satellites to a detection limit as small as 3-m radius. Various observation and analysis strategies are discussed in detail. It is now time to factor the null result of this search into the context of satellite formation among other main belt asteroids and to conduct dynamical modeling to explore the suspected forces contributing to the absence of Satellites at Vesta today.
Geoff Patterson - One of the best experts on this subject based on the ideXlab platform.
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detecting earth s temporarily captured Natural Satellites minimoons
Icarus, 2014Co-Authors: Peter Brown, B. Bolin, Robert Jedicke, Mikael Granvik, Ellen S. Howell, Michael C. Nolan, Peter Jenniskens, Monique Chyba, Geoff PattersonAbstract:Abstract We present a study on the discoverability of temporarily captured orbiters (TCOs) by present day or near-term anticipated ground-based and space-based facilities. TCOs (Granvik, M., Vaubaillon, J., Jedicke, R. [2012]. Icarus 218, 262–277) are potential targets for spacecraft rendezvous or human exploration (Chyba, M., Patterson, G., Picot, G., Granvik, M., Jedicke, R., Vaubaillon, J. [2014]. J. Indust. Manage. Optim. 10, 477–501) and provide an opportunity to study the population of the smallest asteroids in the Solar System. We find that present day ground-based optical surveys such as Pan-STARRS and ATLAS can discover the largest TCOs over years of operation. A targeted survey conducted with the Subaru telescope can discover TCOs in the 0.5–1.0 m diameter size range in about 5 nights of observing. Furthermore, we discuss the application of space-based infrared surveys, such as NEOWISE, and ground-based meteor detection systems such as CAMS, CAMO and ASGARD in discovering TCOs. These systems can detect TCOs but at a uninteresting rate. Finally, we discuss the application of bi-static radar at Arecibo and Green Bank to discover TCOs. Our radar simulations are strongly dependent on the rotation rate distribution of the smallest asteroids but with an optimistic distribution we find that these systems have >80% chance of detecting a >10 cm diameter TCO in about 40 h of operation.
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Detecting Earth’s temporarily-captured Natural Satellites—Minimoons
Icarus, 2014Co-Authors: B. Bolin, Peter Brown, Robert Jedicke, Mikael Granvik, Ellen S. Howell, Michael C. Nolan, Peter Jenniskens, Monique Chyba, Geoff Patterson, Richard J. WainscoatAbstract:Abstract We present a study on the discoverability of temporarily captured orbiters (TCOs) by present day or near-term anticipated ground-based and space-based facilities. TCOs (Granvik, M., Vaubaillon, J., Jedicke, R. [2012]. Icarus 218, 262–277) are potential targets for spacecraft rendezvous or human exploration (Chyba, M., Patterson, G., Picot, G., Granvik, M., Jedicke, R., Vaubaillon, J. [2014]. J. Indust. Manage. Optim. 10, 477–501) and provide an opportunity to study the population of the smallest asteroids in the Solar System. We find that present day ground-based optical surveys such as Pan-STARRS and ATLAS can discover the largest TCOs over years of operation. A targeted survey conducted with the Subaru telescope can discover TCOs in the 0.5–1.0 m diameter size range in about 5 nights of observing. Furthermore, we discuss the application of space-based infrared surveys, such as NEOWISE, and ground-based meteor detection systems such as CAMS, CAMO and ASGARD in discovering TCOs. These systems can detect TCOs but at a uninteresting rate. Finally, we discuss the application of bi-static radar at Arecibo and Green Bank to discover TCOs. Our radar simulations are strongly dependent on the rotation rate distribution of the smallest asteroids but with an optimistic distribution we find that these systems have >80% chance of detecting a >10 cm diameter TCO in about 40 h of operation.
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Earth's Temporarily-Captured Natural Satellites - The First Step towards Utilization of Asteroid Resources
Asteroids, 2013Co-Authors: Mikael Granvik, Robert Jedicke, Monique Chyba, Geoff Patterson, Bryce Bolin, Gautier PicotAbstract:Granvik et al. (2012) predict that the Earth is surrounded by a cloud of small temporarily-captured asteroids. These temporarily-captured orbiters (TCOs) originate in the near-Earth-object (NEO) population and are temporarily captured in the potential well of the Earth-Moon system (EMS). Granvik et al. (2012) predict that the largest object in orbit around Earth at any given moment (other than the Moon) has a diameter D ~1 m (Sect. 6.2). The number of TCOs is inversely proportional to their size such that there are on the order of 103 0.1-meter-diameter TCOs in orbit around Earth at any given time.
