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| | It's painful to have hemorrhoids. This can be a big hindrance for a daily routine. You cannot do all the things that we employ to do due to the pain that you are going from.<br><br>Aloe Vera Gel is excellent for relieving a symptoms while you're waiting for a more permanent solution to commence functioning, like the Herbal [http://hemorrhoidtreatmentfix.com/thrombosed-hemorrhoid thrombosed hemorrhoids] for illustration.<br><br>And then there was the casual bleeding. Once whenever I removed my light colored trousers at the end of the day, I noticed a small blood stain spot showing on the outside. How embarrassing! I wonder how several persons saw that plus were too polite to mention anything!<br><br>Venapro is really wonderful considering there is no need for awkward moments in the toilet wherein we have to place cream on your anus. Just spritz it plus you're done. In as short as 3 days, positive effects are felt.<br><br>This 1 is anything I recommend you commence doing right away, if you're not already. It's the easiest all-natural hemorrhoids remedy to begin utilizing, plus it undoubtedly will create a difference. Among its several other health advantages, a diet excellent in fiber and with a lot of water consumption makes a stool much easier to pass. By being more gentle on a behind, you'll enable your hemorrhoids to heal plus avoid future developments. Plus, it's basically free. So if you choose 1 natural cure, choose this one.<br><br>Well, because it turns out there are a lot of choices. I can't remember all fancy names, nevertheless I remember rubber bands, lasers, and surgery with REAL scalpels being reported. Yes, the entire range from medieval torture instruments to Star Wars weapons. And they sought to use THOSE details - in THAT area!<br><br>So what are these treatments? These are typically the secure, natural, plus fast acting remedies that you need to begin using right away. They go after the causes of the hemorrhoids instead of just covering up a symptoms for a brief period. Unless you've gotten attached to the continual pain and itching, and the blood coming from your butt, do oneself a favor and receive started on one of these remedies now. |
| A '''geosynchronous transfer orbit''' or '''geostationary transfer orbit''' ('''GTO''') is a [[Hohmann transfer orbit]] used to reach [[geosynchronous orbit|geosynchronous]] or [[geostationary orbit]].<ref name=smad2ed>
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| Larson, Wiley J. and James R. Wertz, eds. Space Mission Design and Analysis, 2nd Edition. Published jointly by Microcosm, Inc. (Torrance, CA) and Kluwer Academic Publishers (Dordrecht/Boston/London). 1991.</ref>
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| It is a highly [[ellipse|elliptical]] Earth [[orbit]] with an [[apogee]] of {{convert|42164|km|mi|-3|abbr=on}},<ref>
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| {{cite book |title=Fundamentals of Astrodynamics and Applications |last=Vallado |first=David A. |year=2007 |publisher=Microcosm Press |location=Hawthorne, CA |pages=31 }}
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| </ref> or {{convert|35786|km|mi|-3|abbr=on}} above sea level, which corresponds to the geostationary (GEO) altitude. The [[argument of perigee]] is such that apogee occurs on or near the equator. Perigee can be anywhere above the atmosphere, but is usually restricted to a few hundred kilometers above the Earth's surface to [[Oberth_effect|reduce launcher delta-V (<math>\Delta</math>V)]] requirements and to [[Orbital_decay|limit the orbital lifetime of the spent booster]].
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| The [[inclination]] of a GTO is the angle between the orbit plane and the Earth's [[equator|equatorial plane]]. It is determined by the [[latitude]] of the launch site and the launch [[azimuth]] (direction). The inclination and eccentricity must both be reduced to zero to obtain a geostationary orbit. If only the [[Orbital eccentricity|eccentricity]] of the orbit is reduced to zero, the result is a geosynchronous orbit. Because the <math>\Delta</math>V required for a plane change is proportional to the instantaneous velocity, the inclination and eccentricity are usually changed together in a single manoeuvre at apogee where velocity is lowest.
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| ==Technical description==
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| The required <math>\Delta</math>V for an inclination change at either the ascending or descending [[orbital node|node]] of the orbit is calculated as follows:<ref>Curtis, H.D. (2010) Orbital Mechanics for Engineering Students, 2nd Ed. Elsevier, Burlington, MA, pp. 356-357.</ref>
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| :<math>\Delta V = 2 V \sin \frac{\Delta i}{2}</math>
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| For a typical GTO with a [[semimajor axis]] of 24,582 km, [[perigee]] velocity is 9.88 km/s and [[apogee]] velocity is 1.64 km/s, clearly making the inclination change far less costly at apogee. In practice, the inclination change is combined with the orbital circularization (or "[[apogee kick]]") burn to reduce the total <math>\Delta</math>V for the two maneuvers. The combined <math>\Delta</math>V is the vector sum of the inclination change <math>\Delta</math>V and the circularization <math>\Delta</math>V, and as the sum of the lengths two sides of a triangle will always exceed the remaining side's length, total <math>\Delta</math>V in a combined maneuver will always be less than in two maneuvers. The combined <math>\Delta</math>V can be calculated as follows:<ref>Curtis, H.D. (2010) Orbital Mechanics for Engineering Students, 2nd Ed. Elsevier, Burlington, MA, pp. 356-357.</ref>
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| :<math>\Delta V = \sqrt{ V_{t,a}^{2} + V_{GEO}^{2} - 2 V_{t,a} V_{GEO} \cos \Delta i}</math>
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| where <math>V_{t,a}</math> is the velocity magnitude at the apogee of the transfer orbit and <math>V_{GEO}</math> is the velocity in GEO.
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| ==Other considerations==
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| Even at apogee, the fuel needed to reduce inclination to zero can be significant, giving equatorial launch sites a substantial advantage over those at higher latitudes. [[Baikonur Cosmodrome]] in [[Kazakhstan]] is at 46 degrees north latitude. [[Kennedy Space Center]] is at 28.5 degrees north. [[Guiana Space Centre]], the [[Ariane (rocket family)|Ariane]] launch facility, is at [[5th parallel north|5 degrees north]]. [[Sea Launch]] launches from a floating platform directly on the equator in the [[Pacific Ocean]].
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| [[Expendable launch system|Expendable]] launchers generally reach GTO directly, but a spacecraft already in a low Earth orbit ([[Low Earth orbit|LEO]]) can enter GTO by firing a [[rocket]] along its orbital direction to increase its velocity. This was done when geostationary spacecraft were launched from the [[space shuttle]]; a "perigee kick motor" attached to the spacecraft ignited after the shuttle had released it and withdrawn to a safe distance.
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| Although some launchers can take their payloads all the way to geostationary orbit, most end their missions by releasing their payloads into GTO. The spacecraft and its operator are then responsible for the manoeuvre into the final geostationary orbit. The five-hour coast to first apogee can be longer than the battery lifetime of the launcher or spacecraft, and the manoeuvre is sometimes performed at a later apogee or split among multiple apogees. The solar power available on the spacecraft supports the mission after launcher separation. Also, many launchers now carry several satellites in each launch to reduce overall costs, and this practice simplifies the mission when the payloads may be destined for different orbital positions.
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| Because of this practice, launcher capacity is usually quoted as spacecraft mass to GTO, and this number will be higher than the payload that could be delivered directly into GEO.
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| For example, the capacity (adapter and spacecraft mass) of the [[Delta IV rocket|Delta IV]] Heavy is:<ref>United Launch Alliance, ''Delta IV Launch Services User's Guide'' June 2013, pp. 2-10, Figure 2-9; http://www.ulalaunch.com/site/docs/product_cards/guides/Delta%20IV%20Users%20Guide%20June%202013.pdf accessed 2013 July 27</ref>
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| *GTO 14,220 kg (185 km x 35,786 km at 27.0 deg inclination), theoretically more than any other currently available launch vehicle (it is not known to have flown with such a payload yet)
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| *GEO 6,750 kg
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| If the manoeuvre from GTO to GEO is to be performed with a single impulse, as with a single solid rocket motor, apogee must occur at an equatorial crossing and at synchronous orbit altitude. This implies an argument of perigee of either 0 or 180 degrees. Because the argument of perigee is slowly perturbed by the oblateness of the Earth, it is usually biased at launch so that it reaches the desired value at the appropriate time (for example, this is usually the sixth apogee on [[Ariane 5]] launches<ref>ArianeSpace, ''Ariane 5 User's Manual'' Issue 5 Revision 1, 2011 July, pp. 2-13, http://www.arianespace.com/launch-services-ariane5/Ariane-5-User%27s-Manual.asp accessed 2013 July 27</ref>). If the GTO inclination is zero, as with Sea Launch, then this does not apply. (It also would not apply to an impractical GTO inclined at 63.4 degrees; see [[Molniya Orbit]].)
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| The preceding discussion has primarily focused on the case where the transfer between LEO and GEO is done with a single intermediate transfer orbit. More complicated trajectories are sometimes used. For example, the [[Proton_(rocket)#Proton_M|Proton M]] uses a set of three intermediate orbits, requiring five upper stage rocket firings, to place a satellite into GEO from the high-inclination site of [[Baikonur Cosmodrome]], in [[Kazakhstan]].<ref>International Launch Services, ''Proton Mission Planner's Guide'' Rev. 7 2009 November, pp. 2-13, Figure 2.3.2-1, http://www.ilslaunch.com/sites/default/files/pdf/Proton%20Mission%20Planner%27s%20Guide%20Revision%207%20%28LKEB-9812-1990%29.pdf accessed 2013 July 27</ref> Because of Baikonur's high latitude and range safety considerations that block launches directly east, it requires less delta-v to transfer satellites to GEO by using a [[Supersynchronous orbit|supersynchronous transfer orbit]] where the apogee (and the maneuver to reduce the transfer orbit inclination) are at a higher altitude than 35,786km, the geosynchronous altitude. Proton even offers to perform a supersynchronous apogee maneuver up to fifteen hours after launch. <ref>ibid. Appendix F.4.2, page F-8</ref>
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| ==See also==
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| {{Portal|Spaceflight}}
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| * [[Astrodynamics]]
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| * [[Low Earth orbit]]
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| * [[List of orbits]]
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| == References ==
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| {{reflist}}
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| {{orbits}}
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| [[Category:Astrodynamics]]
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| [[Category:Earth orbits]]
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It's painful to have hemorrhoids. This can be a big hindrance for a daily routine. You cannot do all the things that we employ to do due to the pain that you are going from.
Aloe Vera Gel is excellent for relieving a symptoms while you're waiting for a more permanent solution to commence functioning, like the Herbal thrombosed hemorrhoids for illustration.
And then there was the casual bleeding. Once whenever I removed my light colored trousers at the end of the day, I noticed a small blood stain spot showing on the outside. How embarrassing! I wonder how several persons saw that plus were too polite to mention anything!
Venapro is really wonderful considering there is no need for awkward moments in the toilet wherein we have to place cream on your anus. Just spritz it plus you're done. In as short as 3 days, positive effects are felt.
This 1 is anything I recommend you commence doing right away, if you're not already. It's the easiest all-natural hemorrhoids remedy to begin utilizing, plus it undoubtedly will create a difference. Among its several other health advantages, a diet excellent in fiber and with a lot of water consumption makes a stool much easier to pass. By being more gentle on a behind, you'll enable your hemorrhoids to heal plus avoid future developments. Plus, it's basically free. So if you choose 1 natural cure, choose this one.
Well, because it turns out there are a lot of choices. I can't remember all fancy names, nevertheless I remember rubber bands, lasers, and surgery with REAL scalpels being reported. Yes, the entire range from medieval torture instruments to Star Wars weapons. And they sought to use THOSE details - in THAT area!
So what are these treatments? These are typically the secure, natural, plus fast acting remedies that you need to begin using right away. They go after the causes of the hemorrhoids instead of just covering up a symptoms for a brief period. Unless you've gotten attached to the continual pain and itching, and the blood coming from your butt, do oneself a favor and receive started on one of these remedies now.