Difference between revisions of "Talk:KEO"
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:::The concept of "stationary" requires that a spacecraft have both a tiny inclination and a tiny eccentricity. "Synchronous equatorial" acknowledges that the period and the inclination are more important than the eccentricity. You can relax on eccentricity somewhat, as the spacecraft is more likely to stay in the receiving antenna's view area than if your inclination isn't spot-on. If your period isn't matched to Kerbin's rotation, the satellite will drift in longitude and that's the worst. I knew this already, but I do remember Scott Manley (illectro in the forums) explaining this in one of his videos. [[User:Featherwinglove|Featherwinglove]] ([[User talk:Featherwinglove|talk]]) 15:13, 27 July 2013 (CDT) | :::The concept of "stationary" requires that a spacecraft have both a tiny inclination and a tiny eccentricity. "Synchronous equatorial" acknowledges that the period and the inclination are more important than the eccentricity. You can relax on eccentricity somewhat, as the spacecraft is more likely to stay in the receiving antenna's view area than if your inclination isn't spot-on. If your period isn't matched to Kerbin's rotation, the satellite will drift in longitude and that's the worst. I knew this already, but I do remember Scott Manley (illectro in the forums) explaining this in one of his videos. [[User:Featherwinglove|Featherwinglove]] ([[User talk:Featherwinglove|talk]]) 15:13, 27 July 2013 (CDT) | ||
:One thing that's pretty clear to me is that Squad wants derpy (they've responded with everything from flat refusals to outright hostility to suggestions of implementing n-body physics even before the silly-sounding resource flow chart came out.) That's the reason for the in-character stuff (it's also fairly faithful to the situation in real-life, a concept teased by the movie Independence Day where Jeff Goldblum's character "spent eight years at MIT to become a cable repairman" when he's clearly a satellite radio engineer much more educated than a typical DTH installer.) I can understand the confusion regarding "Kerbisynchronous Equatorial Orbit" as KEO, because GEO appears to stand more for "Geosynchronous ''Earth'' Orbit" more than "Geosynchronous ''Equatorial'' Orbit". To be consistent with that concept, GKO for "Geosynchronous Kerbin Orbit" would make more sense (but Mommy, doesn't "geo" mean "Earth"?) As for Clarke Orbit, mother Wiki redirects [https://en.wikipedia.org/wiki/Clarke_orbit Clarke Orbit] to Geostationary Orbit, but [https://en.wikipedia.org/wiki/Geosynchronous_orbit Geosynchronous Orbit] has Clarke's picture (and also acknowledges that Herman Potočnik beat him to it.) Finally, regarding the "citation needed" on the inclination changes, it's simply a matter of doing the trigonometry I mention immediately afterwards. I've actually done two- and three-maneuver optimizations for GEO ascents from Earth by graphing delta-v sums. I learned that supersynchronous transfer orbits suddenly become useful for reducing delta-v if the launch site latitude exceeds 42.1deg (no doubt this value could be different for Kerbin, and might not be sudden either.) This was a surprise because I was expecting either the lowest or highest supersynchronous transfer orbits to become useful first as latitude increased (the highest ones actually do, but it is in less than a tenth of a degree before all supersynchronous orbits were saving delta-v vs. a two maneuver mission.) Of course, this analysis revealed the ideal breakdown for how to change the inclination from the launch site latitude among each of the three maneuvers, and it was always the second maneuver that took up over 90% of the inclination change in the ideal case. In the two maneuver case, this is the apoapsis maneuver, while in the three maneuver case, it is the maneuver that raises the periapsis of the supersynchronous transfer orbit from low altitude to synchronous altitude. In both cases, it is the point at which the spacecraft is traveling slowest in the orbital frame. As for making a KEO page and not synchronous orbit pages for other bodies... well, Earth has hundreds of GEO spacecraft. What about other bodies in the solar system? There isn't a single one! Mariner 9 and the Viking Orbiters got closest, but what they actually did was synchronize their orbits around Mars to ''Earth's'' rotation so that they were consistently downlinking their tapes at the apoapses of their orbits to the Goldstone DSS when observing Mars wasn't as interesting and less likely to be in the way. This was because the first big 64m DSN antenna was at the Goldstone DSS; Canberra and Madrid didn't get theirs until later. Once we have enough (i.e. rovers, landers, people) on the surface of Mars, areosynchronous spacecraft become interesting, but not until then. Oh, yeah, there is one known synchronous satellite in the solar system... but Charon wasn't launched by mankind. [[User:Featherwinglove|Featherwinglove]] ([[User talk:Featherwinglove|talk]]) 15:05, 27 July 2013 (CDT) | :One thing that's pretty clear to me is that Squad wants derpy (they've responded with everything from flat refusals to outright hostility to suggestions of implementing n-body physics even before the silly-sounding resource flow chart came out.) That's the reason for the in-character stuff (it's also fairly faithful to the situation in real-life, a concept teased by the movie Independence Day where Jeff Goldblum's character "spent eight years at MIT to become a cable repairman" when he's clearly a satellite radio engineer much more educated than a typical DTH installer.) I can understand the confusion regarding "Kerbisynchronous Equatorial Orbit" as KEO, because GEO appears to stand more for "Geosynchronous ''Earth'' Orbit" more than "Geosynchronous ''Equatorial'' Orbit". To be consistent with that concept, GKO for "Geosynchronous Kerbin Orbit" would make more sense (but Mommy, doesn't "geo" mean "Earth"?) As for Clarke Orbit, mother Wiki redirects [https://en.wikipedia.org/wiki/Clarke_orbit Clarke Orbit] to Geostationary Orbit, but [https://en.wikipedia.org/wiki/Geosynchronous_orbit Geosynchronous Orbit] has Clarke's picture (and also acknowledges that Herman Potočnik beat him to it.) Finally, regarding the "citation needed" on the inclination changes, it's simply a matter of doing the trigonometry I mention immediately afterwards. I've actually done two- and three-maneuver optimizations for GEO ascents from Earth by graphing delta-v sums. I learned that supersynchronous transfer orbits suddenly become useful for reducing delta-v if the launch site latitude exceeds 42.1deg (no doubt this value could be different for Kerbin, and might not be sudden either.) This was a surprise because I was expecting either the lowest or highest supersynchronous transfer orbits to become useful first as latitude increased (the highest ones actually do, but it is in less than a tenth of a degree before all supersynchronous orbits were saving delta-v vs. a two maneuver mission.) Of course, this analysis revealed the ideal breakdown for how to change the inclination from the launch site latitude among each of the three maneuvers, and it was always the second maneuver that took up over 90% of the inclination change in the ideal case. In the two maneuver case, this is the apoapsis maneuver, while in the three maneuver case, it is the maneuver that raises the periapsis of the supersynchronous transfer orbit from low altitude to synchronous altitude. In both cases, it is the point at which the spacecraft is traveling slowest in the orbital frame. As for making a KEO page and not synchronous orbit pages for other bodies... well, Earth has hundreds of GEO spacecraft. What about other bodies in the solar system? There isn't a single one! Mariner 9 and the Viking Orbiters got closest, but what they actually did was synchronize their orbits around Mars to ''Earth's'' rotation so that they were consistently downlinking their tapes at the apoapses of their orbits to the Goldstone DSS when observing Mars wasn't as interesting and less likely to be in the way. This was because the first big 64m DSN antenna was at the Goldstone DSS; Canberra and Madrid didn't get theirs until later. Once we have enough (i.e. rovers, landers, people) on the surface of Mars, areosynchronous spacecraft become interesting, but not until then. Oh, yeah, there is one known synchronous satellite in the solar system... but Charon wasn't launched by mankind. [[User:Featherwinglove|Featherwinglove]] ([[User talk:Featherwinglove|talk]]) 15:05, 27 July 2013 (CDT) | ||
| + | ::Now that's one wall of text. First of all, regarding in-character. Squad ''is'' being "derpy", both in-game and elsewhere. That doesn't mean that the wiki has to be the same way, we are trying to stay factual here. Also the facts about real-life synchronous orbit craft are not really important in KSP - everyone could go ahead and create network of geosynchronous satellites on other bodies. I also don't see the problem in just making a general article about synchronous orbits and giving it a subsection about stationary and then kerbinstationary orbits. --[[User:Dgelessus|dgelessus]] <sup>([[User talk:Dgelessus|talk]] · [[Special:Contributions/Dgelessus|contribs]])</sup> 16:23, 27 July 2013 (CDT) | ||
Revision as of 21:23, 27 July 2013
Reverting of the introduction
A recent edit reverted the introduction back to its former state, and it was noted in the summary that "more details are on the talk page." Now I don't see anything here... Personally I only partially agree with the revert. The rewrite of the article was not specific to the Kerbinsynchronous Equatorial Orbit (KEO), but was more about synchronous orbits in general. However the old intro was not very good either - it was almost too specific and too in-character ("makes it easier for former cable repairkerbs to install home satellite dishes.") I rewrote it a bit, but I'm still interested in hearing the actual reason for the revert. --dgelessus (talk · contribs) 12:00, 27 July 2013 (CDT)
- About fixing inclination it appears that it is more efficient to do it while at high altitudes and low velocities. And this revert also added this speculation thingy (I don't really know why this is the most popular. It's actually LKO/LEO) and there is a difference between synchronous and stationary. Also I never heard the name “Clark-orbit” before so I edited that. Actually I don't know why there should be only one article about KEO as other celestial bodies also have synchronous orbits. So I'm very interested in the reason for the revert. — xZise [talk] 13:28, 27 July 2013 (CDT)
- Actually I was going to request this being moved to "synchronous orbit", but somehow never got around to it... :/ Also, do I understand this correctly: A synchronous orbit means that an orbiting object takes the same amout of time for a full orbit as the surface of the body it's orbiting, and a stationary orbit is a syonchronous orbit that is equatorial and circular. --dgelessus (talk · contribs) 14:10, 27 July 2013 (CDT)
- Yep. Every stationary orbit is also a synchronous orbit. — xZise [talk] 14:29, 27 July 2013 (CDT)
- The concept of "stationary" requires that a spacecraft have both a tiny inclination and a tiny eccentricity. "Synchronous equatorial" acknowledges that the period and the inclination are more important than the eccentricity. You can relax on eccentricity somewhat, as the spacecraft is more likely to stay in the receiving antenna's view area than if your inclination isn't spot-on. If your period isn't matched to Kerbin's rotation, the satellite will drift in longitude and that's the worst. I knew this already, but I do remember Scott Manley (illectro in the forums) explaining this in one of his videos. Featherwinglove (talk) 15:13, 27 July 2013 (CDT)
- Actually I was going to request this being moved to "synchronous orbit", but somehow never got around to it... :/ Also, do I understand this correctly: A synchronous orbit means that an orbiting object takes the same amout of time for a full orbit as the surface of the body it's orbiting, and a stationary orbit is a syonchronous orbit that is equatorial and circular. --dgelessus (talk · contribs) 14:10, 27 July 2013 (CDT)
- One thing that's pretty clear to me is that Squad wants derpy (they've responded with everything from flat refusals to outright hostility to suggestions of implementing n-body physics even before the silly-sounding resource flow chart came out.) That's the reason for the in-character stuff (it's also fairly faithful to the situation in real-life, a concept teased by the movie Independence Day where Jeff Goldblum's character "spent eight years at MIT to become a cable repairman" when he's clearly a satellite radio engineer much more educated than a typical DTH installer.) I can understand the confusion regarding "Kerbisynchronous Equatorial Orbit" as KEO, because GEO appears to stand more for "Geosynchronous Earth Orbit" more than "Geosynchronous Equatorial Orbit". To be consistent with that concept, GKO for "Geosynchronous Kerbin Orbit" would make more sense (but Mommy, doesn't "geo" mean "Earth"?) As for Clarke Orbit, mother Wiki redirects Clarke Orbit to Geostationary Orbit, but Geosynchronous Orbit has Clarke's picture (and also acknowledges that Herman Potočnik beat him to it.) Finally, regarding the "citation needed" on the inclination changes, it's simply a matter of doing the trigonometry I mention immediately afterwards. I've actually done two- and three-maneuver optimizations for GEO ascents from Earth by graphing delta-v sums. I learned that supersynchronous transfer orbits suddenly become useful for reducing delta-v if the launch site latitude exceeds 42.1deg (no doubt this value could be different for Kerbin, and might not be sudden either.) This was a surprise because I was expecting either the lowest or highest supersynchronous transfer orbits to become useful first as latitude increased (the highest ones actually do, but it is in less than a tenth of a degree before all supersynchronous orbits were saving delta-v vs. a two maneuver mission.) Of course, this analysis revealed the ideal breakdown for how to change the inclination from the launch site latitude among each of the three maneuvers, and it was always the second maneuver that took up over 90% of the inclination change in the ideal case. In the two maneuver case, this is the apoapsis maneuver, while in the three maneuver case, it is the maneuver that raises the periapsis of the supersynchronous transfer orbit from low altitude to synchronous altitude. In both cases, it is the point at which the spacecraft is traveling slowest in the orbital frame. As for making a KEO page and not synchronous orbit pages for other bodies... well, Earth has hundreds of GEO spacecraft. What about other bodies in the solar system? There isn't a single one! Mariner 9 and the Viking Orbiters got closest, but what they actually did was synchronize their orbits around Mars to Earth's rotation so that they were consistently downlinking their tapes at the apoapses of their orbits to the Goldstone DSS when observing Mars wasn't as interesting and less likely to be in the way. This was because the first big 64m DSN antenna was at the Goldstone DSS; Canberra and Madrid didn't get theirs until later. Once we have enough (i.e. rovers, landers, people) on the surface of Mars, areosynchronous spacecraft become interesting, but not until then. Oh, yeah, there is one known synchronous satellite in the solar system... but Charon wasn't launched by mankind. Featherwinglove (talk) 15:05, 27 July 2013 (CDT)
- Now that's one wall of text. First of all, regarding in-character. Squad is being "derpy", both in-game and elsewhere. That doesn't mean that the wiki has to be the same way, we are trying to stay factual here. Also the facts about real-life synchronous orbit craft are not really important in KSP - everyone could go ahead and create network of geosynchronous satellites on other bodies. I also don't see the problem in just making a general article about synchronous orbits and giving it a subsection about stationary and then kerbinstationary orbits. --dgelessus (talk · contribs) 16:23, 27 July 2013 (CDT)
