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S N Samsonov - One of the best experts on this subject based on the ideXlab platform.
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399-Day Variations in Solar Wind Parameters
2020Co-Authors: V E Timofeev, L I Miroshnichenko, S N Samsonov, N G Skryabin, Yu . G. Shafer, M. K. Ammosov, N. V. PushkovAbstract:Based on a large series of data (N=14038) of daily solar-wind densities, we obtained the fluctuation power spectrum. The spectrum shows that the 399-day variation (the Synodic Period of Jupiter) has the largest amplitude in the interval of Periods from 20 to 800 days. The amplitudes of the 399-day variations in solar-wind density, temperature, and speed were determined by superposed epoch analysis:~0.5cm -3 ~8000K, and 2.8 km. s-1 , respectively, at a more than 95% confidence level. This leads us to conclude that the Jupiter may affect the solar- wind parameters, since only it has a 399-day Periodicity in our planetary system.
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Manifestation of the Jupiter's Synodic Period in the solar wind, interplanetary magnetic field and geophysical parameters
Proceedings of the International Astronomical Union, 2009Co-Authors: S N Samsonov, N G SkryabinAbstract:AbstractStudying by the authors of paper of solar wind parameters, namely: density, speed and temperature and also a module of interplanetary magnetic field (IMF) intensity has allowed to find out in them fluctuations with the Period of 399 days. From references it is known that this Period coincidence with the Synodic Period of Jupiter. So long as close by the given Period another source of such fluctuations is not known we have assumed that fluctuations with the Period of 399 days are fluctuations with the Synodic Period of Jupiter. The change of the solar wind plasma parameters and IMF intensity can lead to the change of the Earth's magnetic field parameters and, as a consequence, to the change of charged particle fluxes in the Earth's magnetosphere. On this assumption the IMF intensity in the Earth's vicinity, geomagnetic disturbance (Kp-index) and riometer absorption for the years of 1986-1996 have been analyzed. The analysis of the data has shown the presence of certain changes of these physical parameters with the Period of 399 days. When the Earth and Jupiter were found to be on the same magnetic field line, the IMF intensity was decreasing up to 3.0±0.57, the geomagnetic activity and riometer absorption were decreasing up to 5.2±1.46% and 9.4±2.63%, respectively.
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Manifestation of the 399-day variations in solar wind parameters
Astronomy Letters, 2005Co-Authors: N G Skryabin, V E Timofeev, L I Miroshnichenko, S N SamsonovAbstract:Based on a large series ( N = 14 038) of daily solar wind densities, we obtained the fluctuation power spectrum. The spectrum shows that the 399-day variation (the Synodic Period of Jupiter) has the largest amplitude in the interval of Periods from 20 to 800 days. It is second in magnitude only to the secular, 22-, and 11-year variations. The amplitudes of the 399-day variations in solar wind density, temperature, and speed were determined by a superposed-epoch analysis: ≈0.5 cm^−3, ≈8000 K, and 2.8 km s^−1, respectively, at a more than 95% confidence level. This leads us to conclude that Jupiter may affect the solar wind parameters, since only Jupiter has a 399-day Periodicity in our planetary system.
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manifestation of the jupiter s Synodic Period in the solar wind parameters and ground pressure
2005Co-Authors: V E Timofeev, L I Miroshnichenko, S N Samsonov, N G SkryabinAbstract:On the basis of daily data (n = 14038), a relevance of Jupiter's Synodic Period to the changes in the solar wind parameters and ground pressure has been found. The values of these changes obtained by superposed epoch technique are ≈ 0,5 cm -3 for the solar wind density, ≈ 8000 K for the solar wind temperature, and 1 mb for the ground pressure.
N G Skryabin - One of the best experts on this subject based on the ideXlab platform.
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399-Day Variations in Solar Wind Parameters
2020Co-Authors: V E Timofeev, L I Miroshnichenko, S N Samsonov, N G Skryabin, Yu . G. Shafer, M. K. Ammosov, N. V. PushkovAbstract:Based on a large series of data (N=14038) of daily solar-wind densities, we obtained the fluctuation power spectrum. The spectrum shows that the 399-day variation (the Synodic Period of Jupiter) has the largest amplitude in the interval of Periods from 20 to 800 days. The amplitudes of the 399-day variations in solar-wind density, temperature, and speed were determined by superposed epoch analysis:~0.5cm -3 ~8000K, and 2.8 km. s-1 , respectively, at a more than 95% confidence level. This leads us to conclude that the Jupiter may affect the solar- wind parameters, since only it has a 399-day Periodicity in our planetary system.
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Manifestation of the Jupiter's Synodic Period in the solar wind, interplanetary magnetic field and geophysical parameters
Proceedings of the International Astronomical Union, 2009Co-Authors: S N Samsonov, N G SkryabinAbstract:AbstractStudying by the authors of paper of solar wind parameters, namely: density, speed and temperature and also a module of interplanetary magnetic field (IMF) intensity has allowed to find out in them fluctuations with the Period of 399 days. From references it is known that this Period coincidence with the Synodic Period of Jupiter. So long as close by the given Period another source of such fluctuations is not known we have assumed that fluctuations with the Period of 399 days are fluctuations with the Synodic Period of Jupiter. The change of the solar wind plasma parameters and IMF intensity can lead to the change of the Earth's magnetic field parameters and, as a consequence, to the change of charged particle fluxes in the Earth's magnetosphere. On this assumption the IMF intensity in the Earth's vicinity, geomagnetic disturbance (Kp-index) and riometer absorption for the years of 1986-1996 have been analyzed. The analysis of the data has shown the presence of certain changes of these physical parameters with the Period of 399 days. When the Earth and Jupiter were found to be on the same magnetic field line, the IMF intensity was decreasing up to 3.0±0.57, the geomagnetic activity and riometer absorption were decreasing up to 5.2±1.46% and 9.4±2.63%, respectively.
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Manifestation of the 399-day variations in solar wind parameters
Astronomy Letters, 2005Co-Authors: N G Skryabin, V E Timofeev, L I Miroshnichenko, S N SamsonovAbstract:Based on a large series ( N = 14 038) of daily solar wind densities, we obtained the fluctuation power spectrum. The spectrum shows that the 399-day variation (the Synodic Period of Jupiter) has the largest amplitude in the interval of Periods from 20 to 800 days. It is second in magnitude only to the secular, 22-, and 11-year variations. The amplitudes of the 399-day variations in solar wind density, temperature, and speed were determined by a superposed-epoch analysis: ≈0.5 cm^−3, ≈8000 K, and 2.8 km s^−1, respectively, at a more than 95% confidence level. This leads us to conclude that Jupiter may affect the solar wind parameters, since only Jupiter has a 399-day Periodicity in our planetary system.
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manifestation of the jupiter s Synodic Period in the solar wind parameters and ground pressure
2005Co-Authors: V E Timofeev, L I Miroshnichenko, S N Samsonov, N G SkryabinAbstract:On the basis of daily data (n = 14038), a relevance of Jupiter's Synodic Period to the changes in the solar wind parameters and ground pressure has been found. The values of these changes obtained by superposed epoch technique are ≈ 0,5 cm -3 for the solar wind density, ≈ 8000 K for the solar wind temperature, and 1 mb for the ground pressure.
V E Timofeev - One of the best experts on this subject based on the ideXlab platform.
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399-Day Variations in Solar Wind Parameters
2020Co-Authors: V E Timofeev, L I Miroshnichenko, S N Samsonov, N G Skryabin, Yu . G. Shafer, M. K. Ammosov, N. V. PushkovAbstract:Based on a large series of data (N=14038) of daily solar-wind densities, we obtained the fluctuation power spectrum. The spectrum shows that the 399-day variation (the Synodic Period of Jupiter) has the largest amplitude in the interval of Periods from 20 to 800 days. The amplitudes of the 399-day variations in solar-wind density, temperature, and speed were determined by superposed epoch analysis:~0.5cm -3 ~8000K, and 2.8 km. s-1 , respectively, at a more than 95% confidence level. This leads us to conclude that the Jupiter may affect the solar- wind parameters, since only it has a 399-day Periodicity in our planetary system.
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Manifestation of the 399-day variations in solar wind parameters
Astronomy Letters, 2005Co-Authors: N G Skryabin, V E Timofeev, L I Miroshnichenko, S N SamsonovAbstract:Based on a large series ( N = 14 038) of daily solar wind densities, we obtained the fluctuation power spectrum. The spectrum shows that the 399-day variation (the Synodic Period of Jupiter) has the largest amplitude in the interval of Periods from 20 to 800 days. It is second in magnitude only to the secular, 22-, and 11-year variations. The amplitudes of the 399-day variations in solar wind density, temperature, and speed were determined by a superposed-epoch analysis: ≈0.5 cm^−3, ≈8000 K, and 2.8 km s^−1, respectively, at a more than 95% confidence level. This leads us to conclude that Jupiter may affect the solar wind parameters, since only Jupiter has a 399-day Periodicity in our planetary system.
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manifestation of the jupiter s Synodic Period in the solar wind parameters and ground pressure
2005Co-Authors: V E Timofeev, L I Miroshnichenko, S N Samsonov, N G SkryabinAbstract:On the basis of daily data (n = 14038), a relevance of Jupiter's Synodic Period to the changes in the solar wind parameters and ground pressure has been found. The values of these changes obtained by superposed epoch technique are ≈ 0,5 cm -3 for the solar wind density, ≈ 8000 K for the solar wind temperature, and 1 mb for the ground pressure.
James M Longuski - One of the best experts on this subject based on the ideXlab platform.
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low thrust roundtrip trajectories to mars with one Synodic Period repeat time
Acta Astronautica, 2015Co-Authors: Masataka Okutsu, Damon F Landau, Blake A Rogers, James M LonguskiAbstract:Abstract Cycler trajectories—both ballistic and powered—are reported in the literature in which there are two-vehicle, three-vehicle, and four-vehicle cases. Such trajectories permit the installation of cycler vehicles which provide safe and comfortable living conditions for human space travel between Earth and Mars during every Synodic opportunity. The question the present paper answers is a logical, obvious one: Does a single-vehicle, one-Synodic-Period cycler exist? The answer is yes: such a trajectory can be flown—but only with a high-power electric propulsion system. In our example, it is found that “stopover” trajectories that spend 30 days in orbit about Earth and 30 days about Mars, and return astronauts to Earth in one Synodic Period require a 90-t power generator with a power level of 11 MWe. Fortuitously, and in lieu of using chemical propulsion, the high power level of the electric propulsion system would also be effective in hauling the cargo payload via a spiral trajectory about the Earth. But because one Synodic Period is not enough for the cycler vehicle to fly both the interplanetary trajectories and the Earth-spiral trajectories, we suggest developing two nuclear power generators, which could alternate flying the interplanetary trajectories and the Earth-spiral trajectories. Once these power generators are launched and begin operating in space, the mass requirement in seven subsequent missions (over a Period of 15 years beginning in 2022) would be modest at 250–300 metric tons to low-Earth orbit per mission. Thus two cargo launches of NASA׳s Space Launch System and one crew launch of the Falcon Heavy, for example, would be adequate to maintain support for each consecutive mission. Although we propose developing two sets of electric propulsion systems to account for the Earth-spiral phases, only one vehicle is flown on a heliocentric trajectory at any given time. Thus, our low-thrust stopover cycler with zero encounter velocities falls into a category of a “one-vehicle cycler,” which completes the gap in the literature, where we have already seen multiple-vehicle cycler concepts.
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Preliminary Analysis of Establishing Cycler Trajectories Between Earth and Mars via V? Leveraging
AIAA AAS Astrodynamics Specialist Conference, 2012Co-Authors: Blake A Rogers, James M Longuski, Kyle M. Hughes, Buzz AldrinAbstract:Many cycler concepts have been proposed to provide safe and comfortable quarters for astronauts traveling between the Earth and Mars. However, no literature has appeared to show how these massive vehicles might be placed into their cycler trajectories. In this paper, we explore the use of V1 leveraging to establish cycler vehicles in their desired orbits. In all cases, V1 leveraging reduces the total V to achieve the cycler orbit. In the case of the classic Aldrin cycler, the propellant savings can be as large as 23 metric tons for a cycler vehicle with a dry mass of 70 metric tons. The two-Synodic Period cyclers enjoy lesser gains from V1 leveraging, but have a smaller total mass due to their low approach velocities at Earth and Mars. These characteristics make the two-Synodic Period cyclers attractive for an Earth-Mars human transportation system. If the one-way concept is selected, in which humans remain permanently on Mars, then the number of required two-Synodic Period cycler vehicles drops from four to two. The cycler concept may provide a crucial enabling technology that is safe, economical, and sustainable for the continuous habitation of Mars.
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Reduced Parameterization for Optimization of Low-Thrust Gravity-Assist Trajectories: Case Studies
AIAA AAS Astrodynamics Specialist Conference and Exhibit, 2006Co-Authors: James M LonguskiAbstract:Low-thrust trajectories can be modeled as a series of impulsive ( ΔV) maneuvers connected by conic arcs. We study new ways of parameterizin g the ΔV vectors with a reduced number of variables and constraints. When optimizing low-thrust gravity-assist trajectories, the ΔV magnitudes can be parameterized with switch on/off times of the engine; the steering angles can be parameterized with coefficients of a Chebyshev series. We present numerical results for several missions, including: Earth-Jupiter rendezvous, Earth-MarsVesta flyby, Earth-Mercury rendezvous and a seven-Synodic- Period Earth-Mars roundtrip mission. In most of these cases, we found significant improvements in convergence speed (with acceptable accuracy) with the new formulations.
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notable two Synodic Period earth mars cycler
Journal of Spacecraft and Rockets, 2006Co-Authors: Troy T Mcconaghy, Damon F Landau, James M LonguskiAbstract:Earth-Mars cycler trajectories (cyclers) could play an important role in a future human transportation system to Mars. A particular cycler that repeats every two Synodic Periods and has one intermediate Earth encounter is very promising. In a circular-coplanar model it requires no propulsive maneuvers, has 153-day transfer times between Earth and Mars, and has arrival V ∞ magnitudes of 4.7 km/s at Earth and 5.0 km/s at Mars. A method to find an analog cycler in a more realistic model (i.e., using an accurate ephemeris for the states of Earth and Mars) is described. Two cost metrics are considered: total cycler AV and total cycler AV plus total taxi ΔV. Numerical solutions are presented for both metrics. The total required AV is very small, though not zero. If the Earth-Mars and Mars-Earth transit times are constrained, then the characteristics of the optimal cycler trajectory change. Tradeoffs between maximum transit time and other mission characteristics are analyzed for all possible launch Periods.
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powered earth mars cycler with three Synodic Period repeat time
Journal of Spacecraft and Rockets, 2005Co-Authors: Joseph K Chen, Troy T Mcconaghy, Damon F Landau, James M Longuski, Buzz AldrinAbstract:We construct a cycler (with acceptable transfer times and moderate encounter velocities) by patching a series of three-Synodic-Period semicycler trajectories together. The cycler employs high-efficiency low-thrust propulsion for trajectory maintenance and correction (thus making it a "powered" cycler). Even though the propellant usage is not insignificant, we believe that this cycler still compares favorably with ballistic cyclers (that is, cyclers that do not require deterministic maneuvers), which require four (or more) vehicles, especially when considering the long-term cost to supply and maintain each vehicle. An attractive feature of this cycler is that both short inbound and outbound legs occur within each semicycler segment, thus reducing the number of required vehicles (which provide transfer opportunities every Synodic Period) to only three.
L I Miroshnichenko - One of the best experts on this subject based on the ideXlab platform.
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399-Day Variations in Solar Wind Parameters
2020Co-Authors: V E Timofeev, L I Miroshnichenko, S N Samsonov, N G Skryabin, Yu . G. Shafer, M. K. Ammosov, N. V. PushkovAbstract:Based on a large series of data (N=14038) of daily solar-wind densities, we obtained the fluctuation power spectrum. The spectrum shows that the 399-day variation (the Synodic Period of Jupiter) has the largest amplitude in the interval of Periods from 20 to 800 days. The amplitudes of the 399-day variations in solar-wind density, temperature, and speed were determined by superposed epoch analysis:~0.5cm -3 ~8000K, and 2.8 km. s-1 , respectively, at a more than 95% confidence level. This leads us to conclude that the Jupiter may affect the solar- wind parameters, since only it has a 399-day Periodicity in our planetary system.
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Manifestation of the 399-day variations in solar wind parameters
Astronomy Letters, 2005Co-Authors: N G Skryabin, V E Timofeev, L I Miroshnichenko, S N SamsonovAbstract:Based on a large series ( N = 14 038) of daily solar wind densities, we obtained the fluctuation power spectrum. The spectrum shows that the 399-day variation (the Synodic Period of Jupiter) has the largest amplitude in the interval of Periods from 20 to 800 days. It is second in magnitude only to the secular, 22-, and 11-year variations. The amplitudes of the 399-day variations in solar wind density, temperature, and speed were determined by a superposed-epoch analysis: ≈0.5 cm^−3, ≈8000 K, and 2.8 km s^−1, respectively, at a more than 95% confidence level. This leads us to conclude that Jupiter may affect the solar wind parameters, since only Jupiter has a 399-day Periodicity in our planetary system.
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manifestation of the jupiter s Synodic Period in the solar wind parameters and ground pressure
2005Co-Authors: V E Timofeev, L I Miroshnichenko, S N Samsonov, N G SkryabinAbstract:On the basis of daily data (n = 14038), a relevance of Jupiter's Synodic Period to the changes in the solar wind parameters and ground pressure has been found. The values of these changes obtained by superposed epoch technique are ≈ 0,5 cm -3 for the solar wind density, ≈ 8000 K for the solar wind temperature, and 1 mb for the ground pressure.
