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In this study, the first kind Bessel function was used to solve Kepler equation for an elliptical orbiting satellite. It is a classical method that gives a direct solution for calculation of the eccentric anomaly. It was solved for one period from (M=0-360)° with an eccentricity of (e=0-1) and the number of terms from (N=1-10). Also, the error in the representation of the first kind Bessel function was calculated. The results indicated that for eccentricity of (0.1-0.4) and (N = 1-10), the values of eccentric anomaly gave a good result as compared with the exact solution. Besides, the obtained eccentric anomaly values were unaffected by increasing the number of terms (N = 6-10) for eccentricities (0.8 and 0.9). The Bessel function's solution appeared to be close to the exact solution for eccentricity of 1 and more than 10 number of terms. Finally, the representation of the first kind Bessel function J1(x) was closer to the exact representation only for eccentricity 0.5 and (N=1-10).

In this research, the eccentricity will be calculated as well as the best height of satellite orbit that can used to transfer from that orbit around the Earth to construct an interplanetary trajectory, for example Mars, when the transfer can be accomplished by a simple impulse, that means the transfer consists of an elliptical orbit from the inner orbit (at a perigee point) to the outer orbit (at apogee point). We will determine Keplerian equation to find the value of a mean anomaly(M) by Rung-Cutta method.
There are several types of satellites orbits around the Earth, but by this study, we find that the best stable orbit to the satellite that is used to inter its orbit around Mars is the Medium Earth Orbit (MEO) at a height about 3500km above the Earth surface. (MEO) comprises a wide range of orbits anywhere between LEO and GEO, its height above the Earth surface is about 2000-35700 km, and it is very commonly used by navigation satellites.
The values ​​of Euler angles (i=23.45°, Ω=20°, w=60°) were installed and the values ​​of each of the height of the perigee point were changed by controlling the height from the ground surface (hp=500, 3500, 35800) km and the eccentricity of the orbit from e=0.1 to 0.9. We found that the best stable orbit of the satellite around the Earth in preparation for its transition to another orbit around Mars is at an altitude of 3500 km, with eccentricity of approximately 0.6, because this orbit was the most stable according to the program results shown in the graphs (no.10) because at the perigee of the orbit we obtained the highest escape speed was approximately 8 km/sec, which means the possibility of transfer with the lowest possible energy.

The perturbed equation of motion can be solved by using many numerical methods. Most of these solutions were inaccurate; the fourth order Adams-Bashforth method is a good numerical integration method, which was used in this research to study the variation of orbital elements under atmospheric drag influence. A satellite in a Low Earth Orbit (LEO), with altitude form perigee = 200 km, was selected during 1300 revolutions (84.23 days) and ASat / MSat value of 5.1 m2/ 900 kg. The equations of converting state vectors into orbital elements were applied. Also, various orbital elements were evaluated and analyzed. The results showed that, for the semi-major axis, eccentricity and inclination have a secular falling discrepancy, Longitude of Ascending Node is periodic, Argument of Perigee has a secular increasing variation, while true anomaly grows linearly from 0 to 360°. Furthermore, all orbital elements, excluding Longitude of Ascending Node, Argument of Perigee, and true anomaly, were more affected by drag than other orbital elements, through their falling as the time passes. The results illustrate a high correlation as compared with literature reviews in this field.

An evaluation was achieved by designing a matlab program to solve Kepler's equation of an elliptical orbit for methods (Newton-Raphson, Danby, Halley and Mikkola). This involves calculating the Eccentric anomaly (E) from mean anomaly (M=0°-360°) for each step and for different values of eccentricities (e=0.1, 0.3, 0.5, 0.7 and 0.9). The results of E were demonstrated that Newton's- Raphson Danby's, Halley's can be used for e between (0-1). Mikkola's method can be used for e between (0-0.6).The term that added to Danby's method to obtain the solution of Kepler's equation is not influence too much on the value of E. The most appropriate initial Gauss value was also determined to be (En=M), this initial value gave a good result for (E) for these methods regardless the value of e to increasing the accuracy of E. After that the orbital elements converting into state vectors within one orbital period within time 50 second, the results demonstrated that all these four methods can be used in semi-circular orbit, but in case of elliptical orbit Danby's and Halley's method use only for e ≤ 0.7, Mikkola's method for e ≤ 0.01 while Newton-Raphson uses for e < 1, which considers more applicable than others to use in semi-circular and elliptical orbit. The results gave a good agreement as compared with the state vectors of Cartosat-2B satellite that available on Two Line Element (TLE).

Abstract In the field of political behavior, tolerance is a crucial element to keep harmonious relationship. Studies should be able to measure a valid construct of tolerance in an effort to understand it further. Ferrar (1979) conducted a research focusing on the concept of political tolerance and theorized political tolerance to have three dimensions, namely flexible, approval, and allowance. This study aims to construct a political tolerance scale based on Ferrar's concept and dimensions. Confirmatory Factor Analysis (CFA) is employed to test the construct validity and dimensionality of the Political Tolerance Scale. Participants were 300 Indonesian-Muslims. The results support the Political Tolerance Scale as a unidimensional scale consists of flexible, approval, and allowance dimensions. However, the limitation of the samples' characteristic suggests future studies to conduct further researches on samples with different characteristics.AbstractDalam ilmu perilaku politik, toleransi adalah merupakan elemen penting untuk menjaga keharmonisan hubungan. Kajian saintifik harus mampu mengukur konstruk toleransi yang valid dalam upaya memahaminya lebih jauh. Ferrar (1979) melakukan penelitian yang berfokus pada konsep toleransi politik dimana toleransi politik diteorikan memiliki tiga dimensi, yaitu fleksibel, persetujuan, dan pengakomodiran. Penelitian ini bertujuan untuk mengkonstruksi alat ukur toleransi politik. Analisis faktor konfirmatori (CFA) digunakan untuk menguji validitas konstruk dan dimensi Skala Toleransi. Pesertanya adalah 300 orang Muslim Indonesia. Hasil yang didapat mendukung Skala Toleransi Politik sebagai skala unidimensional yang terdiri dari dimensi fleksibel, persetujuan, dan pengakomodiran. Namun, keterbatasan karakteristik sampel mendorong studi selanjutnya untuk melakukan penelitian lebih lanjut pada karakteristik sampel yang berbeda.