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Semi-major and semi-minor axes

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It is often said that the semi-major axis is the "average" distance between the primary focus of the ellipse and the orbiting body. This is not quite accurate, because it depends on what the average is taken over. The time- and angle-averaged distance of the orbiting body can vary by 50-100% from the
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lunar orbit, on the other hand, has a semi-major axis of 379,730 km, the Earth's counter-orbit taking up the difference, 4,670 km. The Moon's average barycentric orbital speed is 1.010 km/s, whilst the Earth's is 0.012 km/s. The total of these speeds gives a geocentric lunar
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Note that for a given amount of total mass, the specific energy and the semi-major axis are always the same, regardless of eccentricity or the ratio of the masses. Conversely, for a given total mass and semi-major axis, the total
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and its path relative to its primary are both ellipses. The semi-major axis is sometimes used in astronomy as the primary-to-secondary distance when the mass ratio of the primary to the secondary is significantly large
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The reason for the assumption of prominent elliptical orbits lies probably in the much larger difference between aphelion and perihelion. That difference (or ratio) is also based on the eccentricity and is computed as
988: 3523: 1350: 3396:). However, the minimal difference between the semi-major and semi-minor axes shows that they are virtually circular in appearance. That difference (or ratio) is based on the eccentricity and is computed as 2239: 1127: 3449: 1651:) to the edge of the ellipse. The semi-minor axis is half of the minor axis. The minor axis is the longest line segment perpendicular to the major axis that connects two points on the ellipse's edge. 1192: 2734: 2415: 1260: 3011: 1699: 690: 3138: 3184: 1895: 2522: 1636: 685: 1437: 2088: 2299: 2950: 3337:
with respect to which the elements of the orbit are to be calculated (e.g. geocentric equatorial for an orbit around Earth, or heliocentric ecliptic for an orbit around the Sun),
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can be obtained as the limit of a sequence of ellipses where one focus is kept fixed as the other is allowed to move arbitrarily far away in one direction, keeping
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can be obtained as the limit of a sequence of ellipses where one focus is kept fixed as the other is allowed to move arbitrarily far away in one direction, keeping
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of the minor axis lie at the height of the asymptotes over/under the hyperbola's vertices. Either half of the minor axis is called the semi-minor axis, of length
1694: 2247:, this is important in physics and astronomy, and measure the distance a particle will miss the focus by if its journey is unperturbed by the body at the focus. 2116: 3197: 821:
is, depending on the convention, plus or minus one half of the distance between the two branches. Thus it is the distance from the center to either
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for the curve: in an ellipse, the minor axis is the shorter one; in a hyperbola, it is the one that does not intersect the hyperbola.
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average orbital speed of 1.022 km/s; the same value may be obtained by considering just the geocentric semi-major axis value.
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The semi-minor axis of an ellipse runs from the center of the ellipse (a point halfway between and on the line running between the
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Note that for all ellipses with a given semi-major axis, the orbital period is the same, disregarding their eccentricity.
2165:, the semi-minor and semi-major axes' lengths appear in the equation of the hyperbola relative to these axes as follows: 399: 2762:
may be ignored. Making that assumption and using typical astronomy units results in the simpler form Kepler discovered.
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is the mass of the orbiting body. Typically, the central body's mass is so much greater than the orbiting body's, that
2458: 3102: 3854: 3151: 2959:(the fraction of the orbital period that has elapsed since pericentre, expressed as an angle) gives the time-average 2877: 119: 2859: 808:{\displaystyle {\begin{aligned}b&=a{\sqrt {1-e^{2}}},\\\ell &=a(1-e^{2}),\\a\ell &=b^{2}.\end{aligned}}} 4746: 4626: 4045: 3304: 2448: 1832: 4711: 4465: 2469: 2336:(average of aphelion and perihelion) of some Solar System orbits (crosses denoting Kepler's values) showing that 1590: 2243:
The semi-minor axis is also the distance from one of focuses of the hyperbola to an asymptote. Often called the
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is, depending on the convention, plus or minus one half of the distance between the two branches; if this is
2811: = 0.0549, its semi-minor axis is 383,800 km. Thus the Moon's orbit is almost circular.) The 93: 4731: 4201: 2255: 2909: 4676: 3979:
Williams, Darren M. (November 2003). "Average distance between a star and planet in an eccentric orbit".
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of the ellipse from a focus — that is, of the distances from a focus to the endpoints of the major axis
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of the distance from the center to either focus and the distance from the center to either directrix.
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is the semi-major axis. This form turns out to be a simplification of the general form for the
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The semi-minor axis and the semi-major axis are related through the eccentricity, as follows:
2028:{\displaystyle {\frac {\left(x-h\right)^{2}}{a^{2}}}-{\frac {\left(y-k\right)^{2}}{b^{2}}}=1.} 4774: 4716: 4686: 4474: 4351: 4319: 4289: 4248: 4233: 4112: 3189: 3094: 452: 287: 195: 3050: 3020: 2773: 1775:{\displaystyle {\begin{aligned}b&=a{\sqrt {1-e^{2}}},\\a\ell &=b^{2}.\end{aligned}}} 4799: 4621: 4405: 4294: 4263: 4191: 4166: 4141: 4102: 4083: 4038: 3988: 3537: 1791: 1672: 835: 663: 325: 282: 272: 200: 2535: 2430: 8: 4661: 4456: 4196: 367: 205: 3992: 2098: 4334: 4223: 4121: 3334: 635:. For the special case of a circle, the lengths of the semi-axes are both equal to the 440: 315: 4701: 4599: 4529: 4284: 4238: 4156: 3850: 3581: 3571: 3558: 3547: 2896: 1667: 658: 355: 292: 171: 132: 4681: 4613: 4377: 4339: 4213: 4183: 4136: 3996: 3592: 3384:
is always the same. This statement will always be true under any given conditions.
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The length of the semi-minor axis could also be found using the following formula:
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of a small body orbiting a central body in a circular or elliptical orbit is:
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of a small body orbiting a central body in a circular or elliptical orbit is
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The semi-major axis is the mean value of the maximum and minimum distances
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or one half of the major axis, and thus runs from the centre, through a
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lunar orbit, is 384,400 km. (Given the lunar orbit's eccentricity
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objects, the semi-major axis is related to the period of the orbit by
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Fundamental Planetary Sciences: physics, chemistry, and habitability
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The transverse axis of a hyperbola coincides with the major axis.
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Term in geometry; longest and shortest semidiameters of an ellipse
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In terms of the semi-latus rectum and the eccentricity, we have
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are the distances from each focus to any point in the ellipse.
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Planet orbits are always cited as prime examples of ellipses (
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with the semi-major axis and has one end at the center of the
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Energy; calculation of semi-major axis from state vectors
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The time-averaged value of the reciprocal of the radius,
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In a hyperbola, a conjugate axis or minor axis of length
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of an ellipse is related to the semi-minor axis's length
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orbital semi-major axis, depending on the eccentricity.
2729:{\displaystyle T^{2}={\frac {4\pi ^{2}}{G(M+m)}}a^{3},} 3461: 3402: 3388:
Semi-major and semi-minor axes of the planets' orbits
3361: 3275: 3200: 3154: 3105: 3053: 3023: 2965: 2912: 2776: 2660: 2597: 2538: 2472: 2433: 2410:{\displaystyle T=2\pi {\sqrt {\frac {a^{3}}{\mu }}},} 2372: 2258: 2173: 2128: 2101: 2045: 1935: 1835: 1794: 1697: 1675: 1593: 1565: 1539: 1493: 1447: 1392: 1364: 1272: 1255:{\displaystyle e={\sqrt {1-{\frac {b^{2}}{a^{2}}}}},} 1208: 1150: 1077: 1048: 1021: 891: 838: 688: 666: 3006:{\displaystyle a\left(1+{\frac {e^{2}}{2}}\right)\,} 1358:, with one focus at the origin and the other on the 2565:, the semi-major axis is one of the most important 60:. Unsourced material may be challenged and removed. 3817:1 AU (astronomical unit) equals 149.6 million km. 3517: 3443: 3367: 3293: 3253: 3178: 3132: 3069: 3039: 3005: 2944: 2788: 2728: 2626: 2544: 2516: 2439: 2409: 2293: 2233: 2149: 2110: 2082: 2027: 1889: 1800: 1774: 1681: 1630: 1577: 1551: 1525: 1479: 1431: 1376: 1344: 1254: 1186: 1121: 1061: 1034: 982: 844: 807: 672: 4830: 3844: 3133:{\displaystyle a=-{\frac {\mu }{2\varepsilon }}} 3179:{\displaystyle a={\frac {\mu }{2\varepsilon }}} 3840: 3838: 3836: 3834: 3832: 3830: 3146:and, depending on the convention, the same or 4039: 2425:is the length of the orbit's semi-major axis, 1890:{\displaystyle 2b={\sqrt {(p+q)^{2}-f^{2}}},} 1131:In astronomy these extreme points are called 552: 4018:Semi-major and semi-minor axes of an ellipse 3375:is the specific energy of the orbiting body. 3827: 2858:. Unsourced material may be challenged and 2517:{\displaystyle h={\sqrt {a\mu (1-e^{2})}},} 1631:{\displaystyle a={\frac {\ell }{1-e^{2}}}.} 1004:, in which an arbitrary point is given by ( 4813: 4046: 4032: 3845:Lissauer, Jack J.; de Pater, Imke (2019). 3333:of an orbiting object in coordinates of a 1640:In an ellipse, the semi-major axis is the 559: 545: 3002: 2878:Learn how and when to remove this message 1432:{\displaystyle r(1+e\cos \theta )=\ell .} 1138:The semi-minor axis of an ellipse is the 120:Learn how and when to remove this message 4053: 3978: 3353:is the mass of the gravitating body, and 2323: 2083:{\displaystyle a={\ell \over e^{2}-1}.} 131: 14: 4831: 4692:Transposition, docking, and extraction 2899:indeed results in the semi-major axis. 591:that runs through the center and both 4027: 3881: 2294:{\displaystyle b=a{\sqrt {e^{2}-1}}.} 2945:{\displaystyle b=a{\sqrt {1-e^{2}}}} 2856:adding citations to reliable sources 2823: 2765:The orbiting body's path around the 1927:in the x-direction the equation is: 58:adding citations to reliable sources 29: 3872:, Math Open Reference, 12 May 2013. 2819: 2627:{\displaystyle T^{2}\propto a^{3},} 24: 3955:"7.1 Alternative Characterization" 3908:"7.1 Alternative Characterization" 3870:"Major / Minor axis of an ellipse" 1903:is the distance between the foci, 1658:is related to the semi-major axis 1000:) is the center of the ellipse in 642:The length of the semi-major axis 25: 4855: 4752:Kepler's laws of planetary motion 4011: 2558:is the eccentricity of the orbit. 2319: 871:The major and minor axes are the 331:Kepler's laws of planetary motion 4812: 4747:Interplanetary Transport Network 4627:Collision avoidance (spacecraft) 3305:standard gravitational parameter 3239: 2895:averaging the distance over the 2828: 2449:standard gravitational parameter 161: 69:"Semi-major and semi-minor axes" 34: 4712:Astronomical coordinate systems 4466:Longitude of the ascending node 1307: 45:needs additional citations for 4785:Retrograde and prograde motion 3972: 3947: 3929: 3900: 3875: 3863: 3244: 3234: 2707: 2695: 2506: 2487: 2144: 2129: 1860: 1847: 1520: 1508: 1474: 1462: 1417: 1396: 1336: 1324: 1301: 1289: 1062:{\displaystyle r_{\text{min}}} 1035:{\displaystyle r_{\text{max}}} 949: 936: 908: 895: 883:The equation of an ellipse is 765: 746: 13: 1: 3820: 1526:{\displaystyle r=\ell /(1+e)} 1480:{\displaystyle r=\ell /(1-e)} 1354:Now consider the equation in 627:is a line segment that is at 4732:Equatorial coordinate system 3368:{\displaystyle \varepsilon } 2314: 1914: 1552:{\displaystyle \theta =\pi } 1377:{\displaystyle \theta =\pi } 1200:of an ellipse is defined as 615:, and to the perimeter. The 7: 3981:American Journal of Physics 485:Tsiolkovsky rocket equation 10: 4860: 4484:Longitude of the periapsis 4020:With interactive animation 878: 454:Engineering and efficiency 273:Bi-elliptic transfer orbit 4808: 4795:Specific angular momentum 4700: 4612: 4556: 4492: 4445: 4385: 4376: 4272: 4182: 4071: 4062: 3314:is orbital velocity from 2754:of the central body, and 2459:specific angular momentum 2303:Note that in a hyperbola 2150:{\displaystyle (0,\pm b)} 1919:The semi-major axis of a 1662:through the eccentricity 1578:{\displaystyle \theta =0} 817:The semi-major axis of a 3294:{\displaystyle \mu =GM,} 2349:is constant (green line) 480:Propellant mass fraction 379:Gravitational influences 4790:Specific orbital energy 3529:is easily visualized. 3382:specific orbital energy 3265:specific orbital energy 3093:can be calculated from 2328:Log-log plot of period 351:Specific orbital energy 140:) and semi-minor axis ( 4202:Geostationary transfer 3519: 3445: 3369: 3345:gravitational constant 3318:of an orbiting object, 3295: 3255: 3180: 3134: 3089:, the semi-major axis 3071: 3070:{\displaystyle a^{-1}} 3041: 3040:{\displaystyle r^{-1}} 3007: 2946: 2790: 2789:{\displaystyle M\gg m} 2744:gravitational constant 2730: 2628: 2546: 2518: 2441: 2411: 2350: 2295: 2235: 2151: 2112: 2084: 2029: 1891: 1802: 1776: 1683: 1632: 1579: 1553: 1527: 1481: 1433: 1378: 1346: 1256: 1188: 1123: 1063: 1036: 984: 846: 809: 674: 268:Hohmann transfer orbit 145: 4775:Orbital state vectors 4717:Characteristic energy 4687:Trans-lunar injection 4475:Argument of periapsis 4152:Prograde / Retrograde 4113:Hyperbolic trajectory 3888:mathworld.wolfram.com 3520: 3446: 3370: 3296: 3256: 3190:hyperbolic trajectory 3181: 3135: 3095:orbital state vectors 3072: 3042: 3008: 2947: 2791: 2731: 2629: 2552:are as defined above, 2547: 2519: 2442: 2412: 2327: 2296: 2236: 2152: 2113: 2085: 2030: 1892: 1803: 1801:{\displaystyle \ell } 1777: 1684: 1682:{\displaystyle \ell } 1633: 1580: 1554: 1528: 1482: 1434: 1379: 1347: 1257: 1189: 1124: 1064: 1037: 1002:Cartesian coordinates 985: 847: 845:{\displaystyle \ell } 810: 675: 673:{\displaystyle \ell } 464:Preflight engineering 196:Argument of periapsis 135: 4622:Bi-elliptic transfer 4142:Parabolic trajectory 3459: 3400: 3359: 3273: 3198: 3152: 3103: 3051: 3021: 2963: 2910: 2852:improve this section 2774: 2658: 2595: 2545:{\displaystyle \mu } 2536: 2470: 2451:of the central body. 2440:{\displaystyle \mu } 2431: 2370: 2256: 2171: 2126: 2099: 2043: 1933: 1833: 1792: 1695: 1673: 1654:The semi-minor axis 1591: 1563: 1537: 1491: 1445: 1390: 1362: 1270: 1206: 1148: 1142:of these distances: 1075: 1046: 1019: 889: 836: 686: 664: 520:Propulsive maneuvers 54:improve this article 4662:Low-energy transfer 3993:2003AmJPh..71.1198W 3882:Weisstein, Eric W. 3527:Kepler's second law 2955:averaging over the 2902:averaging over the 2648:, as determined by 2640:is the period, and 2332:vs semi-major axis 2307:can be larger than 623:) of an ellipse or 497:Efficiency measures 400:Sphere of influence 369:Celestial mechanics 151:Part of a series on 4657:Inclination change 4305:Distant retrograde 3515: 3441: 3394:Kepler's first law 3365: 3291: 3251: 3176: 3130: 3067: 3037: 3003: 2942: 2786: 2726: 2624: 2583:Kepler's third law 2542: 2514: 2437: 2407: 2351: 2291: 2231: 2147: 2111:{\displaystyle 2b} 2108: 2080: 2025: 1887: 1816:tend to infinity, 1798: 1772: 1770: 1679: 1628: 1575: 1549: 1523: 1477: 1441:The mean value of 1429: 1374: 1342: 1252: 1184: 1119: 1059: 1032: 980: 860:tend to infinity, 842: 825:of the hyperbola. 805: 803: 670: 316:Dynamical friction 146: 4826: 4825: 4800:Two-line elements 4608: 4607: 4530:Eccentric anomaly 4372: 4371: 4239:Orbit of the Moon 4098:Highly elliptical 4001:10.1119/1.1578073 3987:(11): 1198–1200. 3912:www.geom.uiuc.edu 3815: 3814: 3513: 3484: 3481: 3471: 3439: 3438: 3411: 3249: 3222: 3174: 3128: 2995: 2940: 2897:eccentric anomaly 2888: 2887: 2880: 2711: 2573:, along with its 2509: 2402: 2401: 2286: 2223: 2196: 2075: 2017: 1974: 1882: 1733: 1668:semi-latus rectum 1623: 1356:polar coordinates 1315: 1280: 1247: 1245: 1179: 1176: 1166: 1114: 1107: 1094: 1056: 1029: 969: 928: 724: 659:semi-latus rectum 607:) is the longest 569: 568: 419:Lagrangian points 356:Vis-viva equation 326:Kepler's equation 173:Orbital mechanics 130: 129: 122: 104: 16:(Redirected from 4851: 4816: 4815: 4757:Lagrangian point 4652:Hohmann transfer 4597: 4583: 4574: 4565: 4545: 4536: 4527: 4518: 4514: 4510: 4501: 4481: 4472: 4463: 4454: 4434: 4430: 4421: 4412: 4403: 4383: 4382: 4352:Heliosynchronous 4301:Lagrange points 4254:Transatmospheric 4069: 4068: 4048: 4041: 4034: 4025: 4024: 4005: 4004: 3976: 3970: 3969: 3967: 3966: 3957:. Archived from 3951: 3945: 3944: 3933: 3927: 3926: 3924: 3923: 3914:. Archived from 3904: 3898: 3897: 3895: 3894: 3879: 3873: 3867: 3861: 3860: 3842: 3553:Semi-minor axis 3542:Semi-major axis 3532: 3531: 3524: 3522: 3521: 3516: 3514: 3512: 3501: 3490: 3485: 3483: 3482: 3479: 3473: 3472: 3469: 3463: 3450: 3448: 3447: 3442: 3440: 3437: 3436: 3421: 3417: 3412: 3404: 3374: 3372: 3371: 3366: 3352: 3342: 3325: 3313: 3300: 3298: 3297: 3292: 3260: 3258: 3257: 3252: 3250: 3248: 3247: 3242: 3237: 3228: 3223: 3218: 3217: 3208: 3185: 3183: 3182: 3177: 3175: 3173: 3162: 3144:elliptical orbit 3139: 3137: 3136: 3131: 3129: 3127: 3116: 3092: 3076: 3074: 3073: 3068: 3066: 3065: 3046: 3044: 3043: 3038: 3036: 3035: 3012: 3010: 3009: 3004: 3001: 2997: 2996: 2991: 2990: 2981: 2951: 2949: 2948: 2943: 2941: 2939: 2938: 2923: 2883: 2876: 2872: 2869: 2863: 2832: 2824: 2820:Average distance 2802: 2801: 2795: 2793: 2792: 2787: 2761: 2757: 2749: 2741: 2735: 2733: 2732: 2727: 2722: 2721: 2712: 2710: 2690: 2689: 2688: 2675: 2670: 2669: 2646:two-body problem 2643: 2639: 2633: 2631: 2630: 2625: 2620: 2619: 2607: 2606: 2567:orbital elements 2557: 2551: 2549: 2548: 2543: 2531: 2523: 2521: 2520: 2515: 2510: 2505: 2504: 2480: 2463: 2446: 2444: 2443: 2438: 2424: 2416: 2414: 2413: 2408: 2403: 2397: 2396: 2387: 2386: 2363: 2348: 2347: 2335: 2331: 2310: 2306: 2300: 2298: 2297: 2292: 2287: 2279: 2278: 2269: 2245:impact parameter 2240: 2238: 2237: 2232: 2224: 2222: 2221: 2212: 2211: 2202: 2197: 2195: 2194: 2185: 2184: 2175: 2164: 2160: 2156: 2154: 2153: 2148: 2117: 2115: 2114: 2109: 2089: 2087: 2086: 2081: 2076: 2074: 2067: 2066: 2053: 2034: 2032: 2031: 2026: 2018: 2016: 2015: 2006: 2005: 2000: 1996: 1980: 1975: 1973: 1972: 1963: 1962: 1957: 1953: 1937: 1926: 1910: 1906: 1902: 1896: 1894: 1893: 1888: 1883: 1881: 1880: 1868: 1867: 1846: 1823: 1819: 1815: 1811: 1807: 1805: 1804: 1799: 1781: 1779: 1778: 1773: 1771: 1764: 1763: 1734: 1732: 1731: 1716: 1688: 1686: 1685: 1680: 1665: 1661: 1657: 1637: 1635: 1634: 1629: 1624: 1622: 1621: 1620: 1601: 1584: 1582: 1581: 1576: 1558: 1556: 1555: 1550: 1532: 1530: 1529: 1524: 1507: 1486: 1484: 1483: 1478: 1461: 1438: 1436: 1435: 1430: 1383: 1381: 1380: 1375: 1351: 1349: 1348: 1343: 1317: 1316: 1313: 1282: 1281: 1278: 1261: 1259: 1258: 1253: 1248: 1246: 1244: 1243: 1234: 1233: 1224: 1216: 1193: 1191: 1190: 1185: 1180: 1178: 1177: 1174: 1168: 1167: 1164: 1158: 1128: 1126: 1125: 1120: 1115: 1110: 1109: 1108: 1105: 1096: 1095: 1092: 1085: 1068: 1066: 1065: 1060: 1058: 1057: 1054: 1041: 1039: 1038: 1033: 1031: 1030: 1027: 989: 987: 986: 981: 970: 968: 967: 958: 957: 956: 934: 929: 927: 926: 917: 916: 915: 893: 873:axes of symmetry 867: 863: 859: 855: 851: 849: 848: 843: 814: 812: 811: 806: 804: 797: 796: 764: 763: 725: 723: 722: 707: 679: 677: 676: 671: 656: 649: 645: 561: 554: 547: 526:Orbital maneuver 475:Payload fraction 455: 436:Lissajous orbits 370: 341:Orbital velocity 288:Hyperbolic orbit 184:Orbital elements 174: 165: 148: 147: 136:The semi-major ( 125: 118: 114: 111: 105: 103: 62: 38: 30: 21: 4859: 4858: 4854: 4853: 4852: 4850: 4849: 4848: 4829: 4828: 4827: 4822: 4804: 4722:Escape velocity 4703: 4696: 4677:Rocket equation 4604: 4596: 4590: 4581: 4572: 4563: 4552: 4543: 4534: 4525: 4516: 4512: 4508: 4499: 4488: 4479: 4470: 4461: 4452: 4441: 4432: 4428: 4424:Semi-minor axis 4419: 4415:Semi-major axis 4410: 4401: 4395: 4368: 4290:Areosynchronous 4274: 4268: 4249:Sun-synchronous 4234:Near-equatorial 4178: 4058: 4052: 4014: 4009: 4008: 3977: 3973: 3964: 3962: 3953: 3952: 3948: 3935: 3934: 3930: 3921: 3919: 3906: 3905: 3901: 3892: 3890: 3880: 3876: 3868: 3864: 3857: 3843: 3828: 3823: 3587:Difference (%) 3564:Difference (%) 3502: 3491: 3489: 3478: 3474: 3468: 3464: 3462: 3460: 3457: 3456: 3432: 3428: 3416: 3403: 3401: 3398: 3397: 3390: 3360: 3357: 3356: 3350: 3340: 3335:reference frame 3331:position vector 3321: 3316:velocity vector 3311: 3301: 3274: 3271: 3270: 3261: 3243: 3238: 3233: 3232: 3227: 3213: 3209: 3207: 3199: 3196: 3195: 3186: 3166: 3161: 3153: 3150: 3149: 3140: 3120: 3115: 3104: 3101: 3100: 3090: 3083: 3058: 3054: 3052: 3049: 3048: 3028: 3024: 3022: 3019: 3018: 2986: 2982: 2980: 2973: 2969: 2964: 2961: 2960: 2934: 2930: 2922: 2911: 2908: 2907: 2884: 2873: 2867: 2864: 2849: 2833: 2822: 2799: 2797: 2775: 2772: 2771: 2759: 2755: 2747: 2739: 2736: 2717: 2713: 2691: 2684: 2680: 2676: 2674: 2665: 2661: 2659: 2656: 2655: 2641: 2637: 2634: 2615: 2611: 2602: 2598: 2596: 2593: 2592: 2559: 2555: 2553: 2537: 2534: 2533: 2529: 2524: 2500: 2496: 2479: 2471: 2468: 2467: 2461: 2452: 2432: 2429: 2428: 2426: 2422: 2417: 2392: 2388: 2385: 2371: 2368: 2367: 2361: 2345: 2341: /  2337: 2333: 2329: 2322: 2317: 2308: 2304: 2301: 2274: 2270: 2268: 2257: 2254: 2253: 2241: 2217: 2213: 2207: 2203: 2201: 2190: 2186: 2180: 2176: 2174: 2172: 2169: 2168: 2162: 2158: 2127: 2124: 2123: 2100: 2097: 2096: 2090: 2062: 2058: 2057: 2052: 2044: 2041: 2040: 2035: 2011: 2007: 2001: 1986: 1982: 1981: 1979: 1968: 1964: 1958: 1943: 1939: 1938: 1936: 1934: 1931: 1930: 1924: 1917: 1908: 1904: 1900: 1897: 1876: 1872: 1863: 1859: 1845: 1834: 1831: 1830: 1821: 1817: 1813: 1809: 1793: 1790: 1789: 1782: 1769: 1768: 1759: 1755: 1748: 1739: 1738: 1727: 1723: 1715: 1705: 1698: 1696: 1693: 1692: 1674: 1671: 1670: 1663: 1659: 1655: 1638: 1616: 1612: 1605: 1600: 1592: 1589: 1588: 1564: 1561: 1560: 1538: 1535: 1534: 1503: 1492: 1489: 1488: 1457: 1446: 1443: 1442: 1439: 1391: 1388: 1387: 1363: 1360: 1359: 1352: 1312: 1308: 1277: 1273: 1271: 1268: 1267: 1262: 1239: 1235: 1229: 1225: 1223: 1215: 1207: 1204: 1203: 1194: 1173: 1169: 1163: 1159: 1157: 1149: 1146: 1145: 1129: 1104: 1100: 1091: 1087: 1086: 1084: 1076: 1073: 1072: 1053: 1049: 1047: 1044: 1043: 1026: 1022: 1020: 1017: 1016: 990: 963: 959: 952: 948: 935: 933: 922: 918: 911: 907: 894: 892: 890: 887: 886: 881: 865: 861: 857: 853: 837: 834: 833: 815: 802: 801: 792: 788: 781: 772: 771: 759: 755: 736: 730: 729: 718: 714: 706: 696: 689: 687: 684: 683: 665: 662: 661: 654: 647: 643: 639:of the circle. 617:semi-minor axis 601:semi-major axis 583:is its longest 565: 536: 535: 531:Orbit insertion 521: 513: 512: 498: 490: 489: 465: 457: 453: 446: 445: 441:Lyapunov orbits 432: 431: 415: 405: 404: 380: 372: 368: 361: 360: 346:Surface gravity 321:Escape velocity 311: 303: 302: 283:Parabolic orbit 279: 278: 245: 243: 240:two-body orbits 231: 230: 221:Semi-major axis 186: 176: 172: 144:) of an ellipse 126: 115: 109: 106: 63: 61: 51: 39: 28: 23: 22: 15: 12: 11: 5: 4857: 4847: 4846: 4841: 4839:Conic sections 4824: 4823: 4821: 4820: 4818:List of orbits 4809: 4806: 4805: 4803: 4802: 4797: 4792: 4787: 4782: 4777: 4772: 4770:Orbit equation 4767: 4759: 4754: 4749: 4744: 4739: 4734: 4729: 4724: 4719: 4714: 4708: 4706: 4698: 4697: 4695: 4694: 4689: 4684: 4679: 4674: 4669: 4664: 4659: 4654: 4649: 4644: 4642:Gravity assist 4639: 4637:Delta-v budget 4634: 4629: 4624: 4618: 4616: 4610: 4609: 4606: 4605: 4603: 4602: 4594: 4588: 4579: 4570: 4568:Orbital period 4560: 4558: 4554: 4553: 4551: 4550: 4548:True longitude 4541: 4539:Mean longitude 4532: 4523: 4506: 4496: 4494: 4490: 4489: 4487: 4486: 4477: 4468: 4459: 4449: 4447: 4443: 4442: 4440: 4439: 4426: 4417: 4408: 4398: 4396: 4394: 4393: 4390: 4386: 4380: 4374: 4373: 4370: 4369: 4367: 4366: 4365: 4364: 4356: 4355: 4354: 4349: 4344: 4343: 4342: 4329: 4324: 4323: 4322: 4317: 4312: 4307: 4299: 4298: 4297: 4295:Areostationary 4292: 4287: 4278: 4276: 4270: 4269: 4267: 4266: 4264:Very low Earth 4261: 4256: 4251: 4246: 4241: 4236: 4231: 4226: 4221: 4216: 4211: 4206: 4205: 4204: 4199: 4192:Geosynchronous 4188: 4186: 4180: 4179: 4177: 4176: 4174:Transfer orbit 4171: 4170: 4169: 4164: 4154: 4149: 4144: 4139: 4134: 4132:Lagrange point 4129: 4124: 4115: 4110: 4105: 4100: 4091: 4086: 4081: 4075: 4073: 4066: 4060: 4059: 4054:Gravitational 4051: 4050: 4043: 4036: 4028: 4022: 4021: 4013: 4012:External links 4010: 4007: 4006: 3971: 3946: 3928: 3899: 3874: 3862: 3855: 3825: 3824: 3822: 3819: 3813: 3812: 3809: 3806: 3803: 3800: 3797: 3794: 3791: 3785: 3784: 3781: 3778: 3775: 3772: 3769: 3766: 3763: 3757: 3756: 3753: 3750: 3747: 3744: 3741: 3738: 3735: 3729: 3728: 3725: 3722: 3719: 3716: 3713: 3710: 3707: 3701: 3700: 3697: 3694: 3691: 3688: 3685: 3682: 3679: 3673: 3672: 3669: 3666: 3663: 3660: 3657: 3654: 3651: 3645: 3644: 3641: 3638: 3635: 3632: 3629: 3626: 3623: 3617: 3616: 3613: 3610: 3607: 3604: 3601: 3598: 3595: 3589: 3588: 3585: 3575: 3565: 3562: 3551: 3540: 3535: 3511: 3508: 3505: 3500: 3497: 3494: 3488: 3477: 3467: 3435: 3431: 3427: 3424: 3420: 3415: 3410: 3407: 3389: 3386: 3377: 3376: 3364: 3354: 3348: 3338: 3319: 3290: 3287: 3284: 3281: 3278: 3269: 3246: 3241: 3236: 3231: 3226: 3221: 3216: 3212: 3206: 3203: 3194: 3172: 3169: 3165: 3160: 3157: 3148: 3126: 3123: 3119: 3114: 3111: 3108: 3099: 3082: 3079: 3064: 3061: 3057: 3034: 3031: 3027: 3015: 3014: 3000: 2994: 2989: 2985: 2979: 2976: 2972: 2968: 2953: 2937: 2933: 2929: 2926: 2921: 2918: 2915: 2900: 2886: 2885: 2836: 2834: 2827: 2821: 2818: 2785: 2782: 2779: 2725: 2720: 2716: 2709: 2706: 2703: 2700: 2697: 2694: 2687: 2683: 2679: 2673: 2668: 2664: 2654: 2623: 2618: 2614: 2610: 2605: 2601: 2591: 2575:orbital period 2554: 2541: 2528: 2513: 2508: 2503: 2499: 2495: 2492: 2489: 2486: 2483: 2478: 2475: 2466: 2436: 2427: 2421: 2406: 2400: 2395: 2391: 2384: 2381: 2378: 2375: 2366: 2359:orbital period 2321: 2320:Orbital period 2318: 2316: 2313: 2290: 2285: 2282: 2277: 2273: 2267: 2264: 2261: 2252: 2230: 2227: 2220: 2216: 2210: 2206: 2200: 2193: 2189: 2183: 2179: 2167: 2146: 2143: 2140: 2137: 2134: 2131: 2107: 2104: 2079: 2073: 2070: 2065: 2061: 2056: 2051: 2048: 2039: 2024: 2021: 2014: 2010: 2004: 1999: 1995: 1992: 1989: 1985: 1978: 1971: 1967: 1961: 1956: 1952: 1949: 1946: 1942: 1929: 1916: 1913: 1886: 1879: 1875: 1871: 1866: 1862: 1858: 1855: 1852: 1849: 1844: 1841: 1838: 1829: 1797: 1767: 1762: 1758: 1754: 1751: 1749: 1747: 1744: 1741: 1740: 1737: 1730: 1726: 1722: 1719: 1714: 1711: 1708: 1706: 1704: 1701: 1700: 1691: 1689:, as follows: 1678: 1642:geometric mean 1627: 1619: 1615: 1611: 1608: 1604: 1599: 1596: 1587: 1574: 1571: 1568: 1548: 1545: 1542: 1522: 1519: 1516: 1513: 1510: 1506: 1502: 1499: 1496: 1476: 1473: 1470: 1467: 1464: 1460: 1456: 1453: 1450: 1428: 1425: 1422: 1419: 1416: 1413: 1410: 1407: 1404: 1401: 1398: 1395: 1386: 1373: 1370: 1367: 1341: 1338: 1335: 1332: 1329: 1326: 1323: 1320: 1311: 1306: 1303: 1300: 1297: 1294: 1291: 1288: 1285: 1276: 1266: 1251: 1242: 1238: 1232: 1228: 1222: 1219: 1214: 1211: 1202: 1183: 1172: 1162: 1156: 1153: 1144: 1140:geometric mean 1118: 1113: 1103: 1099: 1090: 1083: 1080: 1071: 1052: 1025: 979: 976: 973: 966: 962: 955: 951: 947: 944: 941: 938: 932: 925: 921: 914: 910: 906: 903: 900: 897: 885: 880: 877: 841: 800: 795: 791: 787: 784: 782: 780: 777: 774: 773: 770: 767: 762: 758: 754: 751: 748: 745: 742: 739: 737: 735: 732: 731: 728: 721: 717: 713: 710: 705: 702: 699: 697: 695: 692: 691: 682: 680:, as follows: 669: 621:minor semiaxis 605:major semiaxis 567: 566: 564: 563: 556: 549: 541: 538: 537: 534: 533: 528: 522: 519: 518: 515: 514: 511: 510: 505: 503:Gravity assist 499: 496: 495: 492: 491: 488: 487: 482: 477: 472: 466: 463: 462: 459: 458: 451: 448: 447: 444: 443: 438: 430: 429: 421: 417: 416: 411: 410: 407: 406: 403: 402: 397: 392: 387: 381: 378: 377: 374: 373: 366: 363: 362: 359: 358: 353: 348: 343: 338: 336:Orbital period 333: 328: 323: 318: 312: 309: 308: 305: 304: 301: 300: 298:Decaying orbit 295: 290: 285: 277: 276: 270: 263: 261:Transfer orbit 259: 258: 257: 255:Elliptic orbit 252: 250:Circular orbit 246: 237: 236: 233: 232: 229: 228: 223: 218: 213: 208: 203: 198: 193: 187: 182: 181: 178: 177: 170: 167: 166: 158: 157: 153: 152: 128: 127: 42: 40: 33: 26: 9: 6: 4: 3: 2: 4856: 4845: 4842: 4840: 4837: 4836: 4834: 4819: 4811: 4810: 4807: 4801: 4798: 4796: 4793: 4791: 4788: 4786: 4783: 4781: 4778: 4776: 4773: 4771: 4768: 4766: 4765:-body problem 4764: 4760: 4758: 4755: 4753: 4750: 4748: 4745: 4743: 4740: 4738: 4735: 4733: 4730: 4728: 4725: 4723: 4720: 4718: 4715: 4713: 4710: 4709: 4707: 4705: 4699: 4693: 4690: 4688: 4685: 4683: 4680: 4678: 4675: 4673: 4670: 4668: 4667:Oberth effect 4665: 4663: 4660: 4658: 4655: 4653: 4650: 4648: 4645: 4643: 4640: 4638: 4635: 4633: 4630: 4628: 4625: 4623: 4620: 4619: 4617: 4615: 4611: 4601: 4593: 4589: 4587: 4586:Orbital speed 4580: 4578: 4571: 4569: 4562: 4561: 4559: 4555: 4549: 4542: 4540: 4533: 4531: 4524: 4522: 4507: 4505: 4498: 4497: 4495: 4491: 4485: 4478: 4476: 4469: 4467: 4460: 4458: 4451: 4450: 4448: 4444: 4438: 4427: 4425: 4418: 4416: 4409: 4407: 4400: 4399: 4397: 4391: 4388: 4387: 4384: 4381: 4379: 4375: 4363: 4360: 4359: 4357: 4353: 4350: 4348: 4345: 4341: 4340:Earth's orbit 4338: 4337: 4336: 4333: 4332: 4330: 4328: 4325: 4321: 4318: 4316: 4313: 4311: 4308: 4306: 4303: 4302: 4300: 4296: 4293: 4291: 4288: 4286: 4283: 4282: 4280: 4279: 4277: 4271: 4265: 4262: 4260: 4257: 4255: 4252: 4250: 4247: 4245: 4242: 4240: 4237: 4235: 4232: 4230: 4227: 4225: 4222: 4220: 4217: 4215: 4212: 4210: 4207: 4203: 4200: 4198: 4197:Geostationary 4195: 4194: 4193: 4190: 4189: 4187: 4185: 4181: 4175: 4172: 4168: 4165: 4163: 4160: 4159: 4158: 4155: 4153: 4150: 4148: 4145: 4143: 4140: 4138: 4135: 4133: 4130: 4128: 4125: 4123: 4119: 4116: 4114: 4111: 4109: 4106: 4104: 4101: 4099: 4095: 4092: 4090: 4087: 4085: 4082: 4080: 4077: 4076: 4074: 4070: 4067: 4065: 4061: 4057: 4049: 4044: 4042: 4037: 4035: 4030: 4029: 4026: 4019: 4016: 4015: 4002: 3998: 3994: 3990: 3986: 3982: 3975: 3961:on 2018-10-24 3960: 3956: 3950: 3942: 3938: 3932: 3918:on 2018-10-24 3917: 3913: 3909: 3903: 3889: 3885: 3878: 3871: 3866: 3858: 3856:9781108411981 3852: 3848: 3841: 3839: 3837: 3835: 3833: 3831: 3826: 3818: 3810: 3807: 3804: 3801: 3798: 3795: 3792: 3790: 3787: 3786: 3782: 3779: 3776: 3773: 3770: 3767: 3764: 3762: 3759: 3758: 3754: 3751: 3748: 3745: 3742: 3739: 3736: 3734: 3731: 3730: 3726: 3723: 3720: 3717: 3714: 3711: 3708: 3706: 3703: 3702: 3698: 3695: 3692: 3689: 3686: 3683: 3680: 3678: 3675: 3674: 3670: 3667: 3664: 3661: 3658: 3655: 3652: 3650: 3647: 3646: 3642: 3639: 3636: 3633: 3630: 3627: 3624: 3622: 3619: 3618: 3614: 3611: 3608: 3605: 3602: 3599: 3596: 3594: 3591: 3590: 3586: 3583: 3579: 3576: 3573: 3569: 3566: 3563: 3560: 3556: 3552: 3549: 3545: 3541: 3539: 3536: 3534: 3533: 3530: 3528: 3509: 3506: 3503: 3498: 3495: 3492: 3486: 3475: 3465: 3452: 3433: 3429: 3425: 3422: 3418: 3413: 3408: 3405: 3395: 3385: 3383: 3362: 3355: 3349: 3346: 3339: 3336: 3332: 3329: 3324: 3320: 3317: 3310: 3309: 3308: 3306: 3288: 3285: 3282: 3279: 3276: 3268: 3266: 3229: 3224: 3219: 3214: 3210: 3204: 3201: 3193: 3191: 3170: 3167: 3163: 3158: 3155: 3147: 3145: 3124: 3121: 3117: 3112: 3109: 3106: 3098: 3096: 3088: 3087:astrodynamics 3078: 3062: 3059: 3055: 3032: 3029: 3025: 2998: 2992: 2987: 2983: 2977: 2974: 2970: 2966: 2958: 2954: 2935: 2931: 2927: 2924: 2919: 2916: 2913: 2905: 2901: 2898: 2894: 2893: 2892: 2882: 2879: 2871: 2861: 2857: 2853: 2847: 2846: 2842: 2837:This section 2835: 2831: 2826: 2825: 2817: 2814: 2810: 2806: 2783: 2780: 2777: 2768: 2763: 2753: 2745: 2723: 2718: 2714: 2704: 2701: 2698: 2692: 2685: 2681: 2677: 2671: 2666: 2662: 2653: 2651: 2647: 2621: 2616: 2612: 2608: 2603: 2599: 2590: 2588: 2584: 2580: 2576: 2572: 2568: 2564: 2539: 2527: 2511: 2501: 2497: 2493: 2490: 2484: 2481: 2476: 2473: 2465: 2460: 2455: 2450: 2434: 2420: 2404: 2398: 2393: 2389: 2382: 2379: 2376: 2373: 2365: 2360: 2356: 2355:astrodynamics 2344: 2340: 2326: 2312: 2288: 2283: 2280: 2275: 2271: 2265: 2262: 2259: 2251: 2248: 2246: 2228: 2225: 2218: 2214: 2208: 2204: 2198: 2191: 2187: 2181: 2177: 2166: 2141: 2138: 2135: 2132: 2121: 2105: 2102: 2093: 2077: 2071: 2068: 2063: 2059: 2054: 2049: 2046: 2038: 2022: 2019: 2012: 2008: 2002: 1997: 1993: 1990: 1987: 1983: 1976: 1969: 1965: 1959: 1954: 1950: 1947: 1944: 1940: 1928: 1922: 1912: 1884: 1877: 1873: 1869: 1864: 1856: 1853: 1850: 1842: 1839: 1836: 1828: 1825: 1795: 1787: 1765: 1760: 1756: 1752: 1750: 1745: 1742: 1735: 1728: 1724: 1720: 1717: 1712: 1709: 1707: 1702: 1690: 1676: 1669: 1652: 1650: 1645: 1643: 1625: 1617: 1613: 1609: 1606: 1602: 1597: 1594: 1586: 1572: 1569: 1566: 1546: 1543: 1540: 1517: 1514: 1511: 1504: 1500: 1497: 1494: 1471: 1468: 1465: 1458: 1454: 1451: 1448: 1426: 1423: 1420: 1414: 1411: 1408: 1405: 1402: 1399: 1393: 1385: 1371: 1368: 1365: 1357: 1339: 1333: 1330: 1327: 1321: 1318: 1309: 1304: 1298: 1295: 1292: 1286: 1283: 1274: 1265: 1249: 1240: 1236: 1230: 1226: 1220: 1217: 1212: 1209: 1201: 1199: 1181: 1170: 1160: 1154: 1151: 1143: 1141: 1136: 1134: 1116: 1111: 1101: 1097: 1088: 1081: 1078: 1070: 1050: 1023: 1013: 1011: 1007: 1003: 999: 995: 977: 974: 971: 964: 960: 953: 945: 942: 939: 930: 923: 919: 912: 904: 901: 898: 884: 876: 874: 869: 839: 831: 826: 824: 820: 798: 793: 789: 785: 783: 778: 775: 768: 760: 756: 752: 749: 743: 740: 738: 733: 726: 719: 715: 711: 708: 703: 700: 698: 693: 681: 667: 660: 653: 640: 638: 634: 633:conic section 630: 626: 622: 618: 614: 610: 606: 602: 598: 594: 590: 586: 582: 578: 574: 562: 557: 555: 550: 548: 543: 542: 540: 539: 532: 529: 527: 524: 523: 517: 516: 509: 508:Oberth effect 506: 504: 501: 500: 494: 493: 486: 483: 481: 478: 476: 473: 471: 468: 467: 461: 460: 456: 450: 449: 442: 439: 437: 434: 433: 427: 423: 422: 420: 414: 413:N-body orbits 409: 408: 401: 398: 396: 395:Perturbations 393: 391: 388: 386: 383: 382: 376: 375: 371: 365: 364: 357: 354: 352: 349: 347: 344: 342: 339: 337: 334: 332: 329: 327: 324: 322: 319: 317: 314: 313: 307: 306: 299: 296: 294: 291: 289: 286: 284: 281: 280: 274: 271: 269: 265: 264: 262: 256: 253: 251: 248: 247: 241: 235: 234: 227: 224: 222: 219: 217: 216:Orbital nodes 214: 212: 209: 207: 204: 202: 199: 197: 194: 192: 189: 188: 185: 180: 179: 175: 169: 168: 164: 160: 159: 156:Astrodynamics 155: 154: 150: 149: 143: 139: 134: 124: 121: 113: 102: 99: 95: 92: 88: 85: 81: 78: 74: 71: –  70: 66: 65:Find sources: 59: 55: 49: 48: 43:This article 41: 37: 32: 31: 19: 4780:Perturbation 4762: 4737:Ground track 4647:Gravity turn 4598:   4591: 4584:   4575:   4566:   4546:   4537:   4528:   4521:True anomaly 4519:   4504:Mean anomaly 4502:   4482:   4473:   4464:   4455:   4435:   4423: 4422:   4414: 4413:   4406:Eccentricity 4404:   4362:Lunar cycler 4335:Heliocentric 4275:other points 4224:Medium Earth 4122:Non-inclined 3984: 3980: 3974: 3963:. Retrieved 3959:the original 3949: 3941:www.bogan.ca 3940: 3931: 3920:. Retrieved 3916:the original 3911: 3902: 3891:. Retrieved 3887: 3877: 3865: 3846: 3816: 3554: 3543: 3538:Eccentricity 3453: 3391: 3378: 3322: 3302: 3262: 3187: 3141: 3084: 3016: 2957:mean anomaly 2904:true anomaly 2889: 2874: 2868:October 2023 2865: 2850:Please help 2838: 2812: 2808: 2804: 2764: 2737: 2635: 2585:(originally 2579:Solar System 2560: 2525: 2456: 2453: 2418: 2352: 2342: 2338: 2302: 2249: 2242: 2094: 2091: 2036: 1918: 1898: 1826: 1820:faster than 1808:fixed. Thus 1783: 1653: 1646: 1639: 1440: 1353: 1263: 1198:eccentricity 1195: 1137: 1130: 1014: 1009: 1005: 997: 993: 991: 882: 870: 864:faster than 852:fixed. Thus 827: 816: 652:eccentricity 650:through the 641: 629:right angles 620: 616: 609:semidiameter 604: 600: 589:line segment 576: 570: 293:Radial orbit 244:eccentricity 226:True anomaly 220: 211:Mean anomaly 201:Eccentricity 141: 137: 116: 107: 97: 90: 83: 76: 64: 52:Please help 47:verification 44: 4742:Hill sphere 4577:Mean motion 4457:Inclination 4446:Orientation 4347:Mars cycler 4285:Areocentric 4157:Synchronous 2813:barycentric 2587:empirically 1384:direction: 426:Halo orbits 390:Hill sphere 206:Inclination 4833:Categories 4682:Rendezvous 4378:Parameters 4214:High Earth 4184:Geocentric 4137:Osculating 4094:Elliptical 3965:2007-09-06 3922:2007-09-06 3893:2024-08-20 3821:References 3568:Perihelion 3307:), where: 2805:geocentric 2767:barycenter 2589:derived): 577:major axis 470:Mass ratio 385:Barycenter 110:March 2017 80:newspapers 18:Minor axis 4727:Ephemeris 4704:mechanics 4614:Maneuvers 4557:Variation 4320:Libration 4315:Lissajous 4219:Low Earth 4209:Graveyard 4108:Horseshoe 3884:"Ellipse" 3799:30.10870 3796:30.11000 3771:19.19770 3768:19.21840 3507:− 3426:− 3363:ε 3328:cartesian 3277:μ 3230:μ 3225:− 3202:ε 3171:ε 3164:μ 3125:ε 3118:μ 3113:− 3060:− 3030:− 2928:− 2839:does not 2781:≫ 2682:π 2609:∝ 2563:astronomy 2540:μ 2494:− 2485:μ 2435:μ 2399:μ 2383:π 2315:Astronomy 2281:− 2199:− 2139:± 2069:− 2055:ℓ 1991:− 1977:− 1948:− 1921:hyperbola 1915:Hyperbola 1870:− 1796:ℓ 1746:ℓ 1721:− 1677:ℓ 1610:− 1603:ℓ 1567:θ 1547:π 1541:θ 1501:ℓ 1469:− 1455:ℓ 1424:ℓ 1415:θ 1412:⁡ 1372:π 1366:θ 1296:− 1221:− 943:− 902:− 840:ℓ 819:hyperbola 779:ℓ 753:− 734:ℓ 712:− 668:ℓ 625:hyperbola 597:perimeter 310:Equations 238:Types of 4493:Position 4118:Inclined 4089:Circular 3743:9.56730 3740:9.58260 3715:5.19820 3712:5.20440 3687:1.51740 3684:1.52400 3659:0.99986 3656:1.00000 3631:0.72298 3628:0.72300 3603:0.37870 3600:0.38700 3578:Aphelion 2120:vertices 1786:parabola 1666:and the 830:parabola 657:and the 585:diameter 573:geometry 4702:Orbital 4672:Phasing 4632:Delta-v 4437:Apsides 4431:,  4229:Molniya 4147:Parking 4084:Capture 4072:General 3989:Bibcode 3808:30.400 3805:29.820 3789:Neptune 3780:20.110 3777:18.330 3752:10.124 3705:Jupiter 3593:Mercury 3343:is the 3142:for an 2860:removed 2845:sources 2750:is the 2742:is the 2526:where: 2447:is the 2419:where: 2346:‍ 1133:apsides 1008:,  996:,  992:where ( 879:Ellipse 581:ellipse 94:scholar 4844:Orbits 4358:Other 4259:Tundra 4127:Kepler 4103:Escape 4056:orbits 3853:  3802:0.004 3793:0.010 3765:0.046 3761:Uranus 3749:9.041 3737:0.057 3733:Saturn 3724:5.459 3721:4.950 3709:0.049 3696:1.666 3693:1.382 3681:0.093 3668:1.017 3665:0.983 3662:0.014 3653:0.017 3640:0.728 3637:0.718 3634:0.002 3625:0.007 3612:0.467 3609:0.307 3597:0.206 3267:) and 3192:, and 3188:for a 2798:81.300 2738:where 2650:Newton 2636:where 2577:. For 2569:of an 1899:where 1533:, for 823:vertex 637:radius 599:. The 579:of an 575:, the 96:  89:  82:  75:  67:  4600:Epoch 4389:Shape 4327:Lunar 4281:Mars 4273:About 4244:Polar 4064:Types 3774:0.11 3746:0.16 3718:0.12 3690:0.44 3649:Earth 3621:Venus 3326:is a 3047:, is 2571:orbit 613:focus 191:Apsis 101:JSTOR 87:books 4392:Size 4331:Sun 4310:Halo 4162:semi 3851:ISBN 3811:1.9 3783:9.7 3677:Mars 3671:3.5 3643:1.4 3606:2.2 2843:any 2841:cite 2752:mass 2532:and 2457:The 2357:the 1907:and 1812:and 1649:foci 1559:and 1487:and 1196:The 1042:and 856:and 593:foci 587:: a 73:news 4167:sub 4079:Box 3997:doi 3755:12 3727:10 3699:21 3615:52 3085:In 2854:by 2561:In 2353:In 1585:is 1409:cos 1314:max 1279:min 1264:so 1175:min 1165:max 1106:min 1093:max 1055:min 1028:max 1012:). 571:In 242:by 56:by 4835:: 4515:, 4511:, 4120:/ 4096:/ 3995:. 3985:71 3983:. 3939:. 3910:. 3886:. 3829:^ 3584:) 3582:AU 3574:) 3572:AU 3561:) 3559:AU 3550:) 3548:AU 3097:: 3077:. 2800:59 2746:, 2652:: 2311:. 2229:1. 2023:1. 1824:. 1784:A 1135:. 868:. 828:A 4763:n 4595:0 4592:t 4582:v 4573:n 4564:T 4544:l 4535:L 4526:E 4517:f 4513:θ 4509:ν 4500:M 4480:ϖ 4471:ω 4462:Ω 4453:i 4433:q 4429:Q 4420:b 4411:a 4402:e 4047:e 4040:t 4033:v 4003:. 3999:: 3991:: 3968:. 3943:. 3925:. 3896:. 3859:. 3580:( 3570:( 3557:( 3555:b 3546:( 3544:a 3510:e 3504:1 3499:e 3496:+ 3493:1 3487:= 3480:p 3476:r 3470:a 3466:r 3434:2 3430:e 3423:1 3419:1 3414:= 3409:b 3406:a 3351:M 3347:, 3341:G 3323:r 3312:v 3303:( 3289:, 3286:M 3283:G 3280:= 3263:( 3245:| 3240:r 3235:| 3220:2 3215:2 3211:v 3205:= 3168:2 3159:= 3156:a 3122:2 3110:= 3107:a 3091:a 3063:1 3056:a 3033:1 3026:r 3013:. 2999:) 2993:2 2988:2 2984:e 2978:+ 2975:1 2971:( 2967:a 2952:. 2936:2 2932:e 2925:1 2920:a 2917:= 2914:b 2881:) 2875:( 2870:) 2866:( 2862:. 2848:. 2809:e 2784:m 2778:M 2770:( 2760:m 2756:m 2748:M 2740:G 2724:, 2719:3 2715:a 2708:) 2705:m 2702:+ 2699:M 2696:( 2693:G 2686:2 2678:4 2672:= 2667:2 2663:T 2642:a 2638:T 2622:, 2617:3 2613:a 2604:2 2600:T 2556:e 2530:a 2512:, 2507:) 2502:2 2498:e 2491:1 2488:( 2482:a 2477:= 2474:h 2462:h 2423:a 2405:, 2394:3 2390:a 2380:2 2377:= 2374:T 2362:T 2343:T 2339:a 2334:a 2330:T 2309:a 2305:b 2289:. 2284:1 2276:2 2272:e 2266:a 2263:= 2260:b 2226:= 2219:2 2215:b 2209:2 2205:y 2192:2 2188:a 2182:2 2178:x 2163:a 2159:b 2145:) 2142:b 2136:, 2133:0 2130:( 2106:b 2103:2 2078:. 2072:1 2064:2 2060:e 2050:= 2047:a 2020:= 2013:2 2009:b 2003:2 1998:) 1994:k 1988:y 1984:( 1970:2 1966:a 1960:2 1955:) 1951:h 1945:x 1941:( 1925:a 1909:q 1905:p 1901:f 1885:, 1878:2 1874:f 1865:2 1861:) 1857:q 1854:+ 1851:p 1848:( 1843:= 1840:b 1837:2 1822:b 1818:a 1814:b 1810:a 1766:. 1761:2 1757:b 1753:= 1743:a 1736:, 1729:2 1725:e 1718:1 1713:a 1710:= 1703:b 1664:e 1660:a 1656:b 1626:. 1618:2 1614:e 1607:1 1598:= 1595:a 1573:0 1570:= 1544:= 1521:) 1518:e 1515:+ 1512:1 1509:( 1505:/ 1498:= 1495:r 1475:) 1472:e 1466:1 1463:( 1459:/ 1452:= 1449:r 1427:. 1421:= 1418:) 1406:e 1403:+ 1400:1 1397:( 1394:r 1369:= 1340:. 1337:) 1334:e 1331:+ 1328:1 1325:( 1322:a 1319:= 1310:r 1305:, 1302:) 1299:e 1293:1 1290:( 1287:a 1284:= 1275:r 1250:, 1241:2 1237:a 1231:2 1227:b 1218:1 1213:= 1210:e 1182:. 1171:r 1161:r 1155:= 1152:b 1117:. 1112:2 1102:r 1098:+ 1089:r 1082:= 1079:a 1051:r 1024:r 1010:y 1006:x 998:k 994:h 978:, 975:1 972:= 965:2 961:b 954:2 950:) 946:k 940:y 937:( 931:+ 924:2 920:a 913:2 909:) 905:h 899:x 896:( 866:b 862:a 858:b 854:a 799:. 794:2 790:b 786:= 776:a 769:, 766:) 761:2 757:e 750:1 747:( 744:a 741:= 727:, 720:2 716:e 709:1 704:a 701:= 694:b 655:e 648:b 644:a 619:( 603:( 560:e 553:t 546:v 428:) 424:( 275:) 266:( 142:b 138:a 123:) 117:( 112:) 108:( 98:· 91:· 84:· 77:· 50:. 20:)

Index

Minor axis

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Orbital mechanics
Orbital elements
Apsis
Argument of periapsis
Eccentricity
Inclination
Mean anomaly
Orbital nodes
Semi-major axis
True anomaly
two-body orbits
Circular orbit
Elliptic orbit
Transfer orbit
Hohmann transfer orbit
Bi-elliptic transfer orbit

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