freeztar Posted September 18, 2008 Report Posted September 18, 2008 Astronomy and Cosmology 2001 Research ProjectThe Dancing Queen and The Mayan Calendar Venus Now Venus Observed Venus is interesting to me because it is so bright and noticeable, yet always fleeting. The sight of Venus must have been spectacular to ancient cultures because of its intensity and notoriety for heralding the day and night. I had intended to watch Venus for the change of phases and to use my data in relating phase changes with the synodic period of Venus. My problem was that I began with the bias that because Venus is an inner planet it should orbit pretty fast and go through phase changes quickly, yet slightly slower than our moon. I began my observations of Venus, naturally, with my naked eye. It is very bright, "as it is the third brightest object (after the Sun and Moon) and has a magnitude of -4" (Audubon 646). I was astonished to notice that I could still see Venus well after the Sun had risen above the horizon. I went to Starry Night to see how long Venus should be visible in the day. Remarkably, I found that during the day I had been observing Venus, it rose at approximately 4:00 A.M. and set, into horizon light, at 3:30 P.M., if one knows where to look. I was able to see Venus well after sunrise because I saw it rise and kept watch, hence I knew where it would be in relation to the sun. Photo taken by freeztar using an Aiptek Pencam through 10x50 binoculars The binoculars I used to view Venus (10x50) were insufficient to see Venus in a phase. I could barely make out the crescent in binoculars. I am convinced I can see the crescent with my naked eye, as seems possible to Anthony Aveni, who notes that, "the sheer size and brightness of this thin disk raise the possibility that Venus could have been viewed as a crescent without the aid of a telescope" (Aveni 32). According to math, however, it seems impossible. The only reasoning I can find is that I wanted to see it and knew what the phase should look like at the time I saw it. Click here to see my math on the angular size of VenusBy extending my observations using the Orion 8- inch Newtonian reflector, I was able to see Venus as a crescent on first observation. It was impossible for me to get a still image due to the sun heating the atmosphere over the horizon and creating a "dancing" image of Venus. I had hoped to see more detail, such as dark areas. Moore and Hunt point out that, " more often than not, some vague elusive features will be glimpsed- provided that conditions are good, and that the telescope is of sufficient aperture" (Moore & Hunt 57). Through the Orion, I was unable to notice any change in the crescent's appearance during my observing, let alone elusive features, despite great conditions. With the help of Starry Night again, I was able to see phase changes of Venus for this year. Interestingly enough, the phases of Venus are easily seen changing on Starry Night with a field of view of 11 arc minutes. Yet, it is still hard to discern phase boundaries in the shading, which makes any chances of predicting period from phases a moot point. It is interesting to note that the phase changes are different each cycle because of the relative positions of the Sun, Venus, and Earth. Click here to see a sketch of Venus displaying phases - looking east Click here to see a sketch of Venus displaying phases - looking west I did a study on starry night to find out what a Venus cycle would look like in 1000 A.D. on the Yucatan Peninsula. I drew some sketches and made a movie showing phase change.Venus has different movement patterns in the Eastern sky than in the Western sky. The thing that is similiar about the loops on either side of the sky are the solstices. As the Sun makes its way North and South of the equator, Venus follows suit because it is bound to the sun. The loop that is seen in the Eastern sky is due to the fact that Venus has just left inferior conjunction and is making its way to superior conjunction. This causes Venus to look like it makes a hesitative loop in the sky for several days because Venus is making its turn around the sun relative to Earth. In the Western sky, when Venus is an evening star, it is heading around the sun towards us. This make the large loop pattern because Venus is now moving towards us and because the turn around the Sun towards inferior conjuction, relative to Earth. The small loop in the Southwestern sky is due to the fact that the sun is around winter solstice while Venus is heading for superior conjunction. Check out the drawing and movie below. Click here to see some sketches of Venus' Eastern and Western sky patterns Click here for a movie in Quicktime of Venus going through phases(Find attachment below) By using Starry Night, I found that Venus follows no regular consistency in the amount of time it remains visible in the Eastern or Western sky, as well as the time it is invisible. If you look at the sketches I made, you will see that Venus spent 208 days in the Eastern sky and 273 days in the Western sky. The period between the Eastern disappearance and Western appearance, 12-30-1000 to 4-4-1001, is around 95 days. These numbers vary year to year. The cycle is not regular. It would take at least eight years of studying the skies, like the ancient Maya did, to compute the synodic period of Venus. Maor points out that the synodic period of Venus is "the time between two consecutive inferior conjunctions" and that "the Maya calendar may have been based on it" (Maor 55). The Maya, through years of patient observation and mysterious intent, were able to find a connection between Earth and Venus such that "the Venus year (~584 days) meshes perfectly with the length of the year of our seasons, 365 days, in the ratio of 5 to 8" (Aveni 30). I have found no evidence that the Maya calculated Venus' sidereal period. How could they unless they had an understanding of the solar system? It seems to me that Venus' sidereal period was a discovery beyond the scope and practicality of Maya astronomers. Why would they need to know the sidereal period of Venus? It is what they saw that was important. It seems as if I should take a step back, and not worry about phases as much as movements, and connections. In other words, perhaps the Goddess of Love is best viewed with a naked eye, free of obscurities. Click here to see a picture of Venus rising over highway 101 Click here to see a picture of Venus rising over highway 101 Cyclic Nature - Use of Venus by the Maya How did the ancient Maya use their observations of Venus? To answer this I strive to eliminate my modern preconceptions because, "unlike her ancient counterpart, the modern Venus is no lady; instead she moves about a vaster sky, an inanimate object to be entered, and dissected with Venera and Magellan spacecraft" (Aveni 17). I strive to envision this "ancient counterpart"; to envision myself as part of an ancient, highly ordered society, which is intricately connected to the movement of the lights in the Sky. "For the classical Maya, the continuity of the power of rulership was directly expressed from the sky-creator in the form of discernable subtleties in observable planetary cycles-Venus most prominent among them" (Aveni 16). Since Venus is the brightest planet and has an unusual cycle, it seems a likely candidate for predictive power. The position of a ruler atop a pyramid, with Venus setting or rising over the ruler's head, would definitely have a powerful effect on a society that deified stars and planets. "By taking his place at the apex of the symbolic program, the king declared himself to be the causal force that perpetuated this order" (Schele & Miller 106). Venus myth also plays an important part in the divine right to rule. For example, a Maya creation story portrays Venus as a "twin who goes into the underworld with his brother the sun to battle these lords of pestilence" and ends up tricking the fiends, making the world what would otherwise be "far worse off with disease than it is today" (Aveni 50). By relating this myth to the quote at the beginning, we can begin to see how the Maya king held great authority through the cosmos. It also seems appropriate that Venus is the sun's twin in this mythology, seeing how Venus is always close to the sun and shines brightly. Mythologies seem to have been of great importance to the Maya, because there are several depictions of superhuman characters on all the Maya temples. I use great skepticism in making any claims that the drawings on Maya temples are myth or deity related, though it seems likely. I find a lot of what I've read to be indigestible. How can we really be sure what we are seeing is what the Maya saw? It is ridiculous to think we can. In none of the books I researched, do they describe how they interpreted the Mayan glyphs. How are they sure that the Venus symbol is not the moon, or a bird in the area? I didn't find good proof for these uncertainties, which disappointed me greatly and leaves me very skeptic. Perhaps the kings were not being worshipped and deified by the sight of Venus, but rather the kings were the leaders in the worship of Venus, their deity. I found that it is also possible that Venus was used for agricultural purposes, in order to know when to plant and harvest. The sun is generally assumed to represent seasonal changes among ancient cultures, so it is a surprise to find that the disappearance time of Venus "is a good index of when the wet and dry periods happen in the seasonal cycle" (Aveni 5). The "good index" might be the average time of disappearance of Venus instead of an actual date to expect the rain. For example, the rainy season, or dry season, may be nine months long, the average disappearance time of Venus in Central Mexico. Imagine being an ancient sky watcher and seeing a correlation of rainy season and Venus appearances. This might be a good crop planting predictor. While waiting for the sun to rise one spring morning, an ancient Maya might have noticed Venus appearing from a long absence and begun the crop planting on that sighting of Venus, knowing the rain was coming. It is not surprising then to find that the Venus symbol is commonly portrayed with Tlaloc, the "god of the storm, rain, and lightning…his meteorological power controlled agricultural fortunes" (Krupp 257). This does not make sense if we look at the irregularity of Venus appearances in different months. This does make sense if we give the 260 day average disappearance of Venus a loose relationship to the rainy season. Interesting enough, I found the climate for Belize to match this fact. I chose Belize because it is in the middle of the Maya civilization. Click here to see the average rainfall in Belize (This site is now defunct. Upon researching this currently, I can find no support for a ~260 day rainy season in Belize. Nonetheless, I think that growing season does not have to match rainy season. Also, we have climate change to throw a wrench in the gears. A reanalysis would be refreshing) It is further suggested by Krupp that Venus was tied to ritual warfare and that by "combining the agricultural abundance implicit in the rains with the status and wealth that accompany tribute won through war, the imagery of Tlaloc-Venus aggression operated as propaganda" (Krupp 257). It seems to me that the Mayans must have needed a good form of advertisement in order to reach all the people under Mayan rule. This makes the deity/planet association even more convincing, but it may be more complex. Perhaps the planets and stars operated on many levels of deities. Or maybe it was simply the Mayan calendar, in which Venus is contained, that was the prognosticator of war and harvest. It is unknown either way, but we can speculate. An interesting coincidence occurs on August 2, 792. On that day Venus was in inferior conjunction and the sun passed through the zenith (Krupp 259). A mural found at Bonampak, interpreted by Floyd Lounsbury to depict events from this date, is supposedly "illustrating battle, sacrifice, and the subjugation of prisoners taken in war" (Krupp 259). Whether we can believe Floyd's interpretation or whether the Maya planned their attacks for this celestial combo is up in the air. We will probably never know. Furthermore, there are fascinating links between the Mayan calendar and Venus that I cannot ignore. The Mayans had a Venus count of 584 days, representing Venus' synodic period (Aveni 7). As I mentioned before, this cycle is matched with the 365-day solar year by a 5/8 ratio. There was also a sacred calendar derived by the Mayans. The Mayan Tzolkin calendar, or Sacred Round of 260 days, may be related to the fact that Venus (as seen from southern Mexico) "lingers and rises in the east as many days as in the west…period of 260 days" (Aveni 78). Is it possible that the Mayans related Venus cycles to the moon cycles as well? To find the relationships of these calendars mathematically, I tried to plug in some numbers and see what I came up with myself. I used a synodic moon period average of 29.5 days and a solar year average of 365.0 days (Audubon 635). Here are my calculations: [math]\frac{365}{29.5}=12.4[/math] synodic moons in one Gregorian year [math]\frac{260}{29.5}=8.8[/math] synodic moons in one Sacred Round [math]\frac{584}{29.5}=19.8[/math] synodic moons in one Venus synodic period [math]584*5=365*8=2920[/math] days in eight solar years and five synodic Venus periods [math]\frac{2920}{29.5}=98.9[/math] synodic moons in one meshing of Venus and Sun synodic periods Both the Venus cycle recorded by the Mayans and the Tzolkin calendar are more evenly divisible by the moon's synodic period than the modern Gregorian calendar we use. It was interesting to see that the closest whole number match, indicating preciseness, is eight solar years and five Venus cycles, divided by the moon's synodic period. This is important to pay attention to because it could let us see into the minds of the ancient Maya calendar makers. The Maya probably created such an elaborate calendar to try to find order in the cosmos. In mathematical terms, this would mean finding the correlation between cycles of multiple heavenly bodies (i.e. 5 Venus years = 8 solar years = 99 moon cycles). For all practical purposes, 98.9 would be close enough to 99 for the Maya. Is this evidence of an intricate association between observed cycles of the three brightest heavenly bodies? It could just be math games. Although, if one believes the myth of the Mayan kings' divine rights through the heavens, the Venus/Moon connection becomes interesting. A Mayan astronomer might have recognized that the moon is in just about the same phase at each Venus cycle renewal. This predicted knowledge could have made the king look bound to the sky in the eyes of observing commoners. Or perhaps it was a need to find a pattern in nature, a way to find order. For after all, order is the base goal of any calendar. Works Cited:Aveni, Anthony. Archaeoastronomy in the New World. Great Britain: Cambridge University Press, 1982 Aveni, Anthony. Conversing with the Planets. New York: Times Books, 1992. Freedman, Roger and William Kaufmann. Universe Fifth Edition. New York: W.H. Freeman, 2000. Hunt, Gary E. and Patrick Moore. The Planet Venus. Boston: Faber and Faber, 1982. Krupp, Edwin C. Skywatchers, Shamans, and Kings. Canada: John Wiley & Son, 1997 Maor, Eli. June 8, 2004: Venus in Transit. New Jersey: Princeton University Press, 2000. Miller, Mary Ellen and Linda Schele. The Blood of Kings. New York: George Braziller, 1986 National Audubon Society. Field Guide to the Night Sky. New York: Knopf 1991. Jay-qu and Boerseun 2 Quote
Tormod Posted September 18, 2008 Report Posted September 18, 2008 VERY nice article. But I can't see your pics - they have disallowed pictures from outside domains. Quote
freeztar Posted September 18, 2008 Author Report Posted September 18, 2008 VERY nice article. But I can't see your pics - they have disallowed pictures from outside domains. Thanks! ;) The pictures show up fine for me, both at home and at work. :D Quote
Tormod Posted September 18, 2008 Report Posted September 18, 2008 Yes, because they are yours? Edit: Click all your links - some go to removed pages etc. :D Quote
Moontanman Posted September 20, 2008 Report Posted September 20, 2008 Really great article Freeztar, I have always found it interesting that celestial objects actually had such a tremendous influence on Early civilizations. "Dancing Queen, Young and Free only Seventeen!":phones: Quote
modest Posted September 24, 2009 Report Posted September 24, 2009 Belated praise on the article and its very attractive investigatory style :thumbs_up With the help of Starry Night again, I was able to see phase changes of Venus for this year... ...I did a study on starry night to find out what a Venus cycle would look like in 1000 A.D. on the Yucatan Peninsula. With Starry Night, can you put in any date and it will show the planets accurately with a sky view? ~modest Quote
freeztar Posted September 24, 2009 Author Report Posted September 24, 2009 Belated praise on the article and its very attractive investigatory style :phones: Thanks. :)With Starry Night, can you put in any date and it will show the planets accurately with a sky view?Yes. You can also zoom out to solar system level and look at where all the planets are, toggle orbital paths, etc. It's a great tool for astronomers. Unfortunately it is a bit pricey, but I think there is a trial version. Hmmm...scratch that, I didn't see one on their site. Looks like they are going for about $30 on ebay. EDIT: There's also some "generic" versions on ebay for $9 including shipping. It seems to be a knockoff of starry night and might be just as good. It does have an impressive list of features like telescope control, dome projection, etc. Quote
modest Posted September 24, 2009 Report Posted September 24, 2009 Fantastic. I'll have to see if I can find a torrent. This had reminded me of Celestia, which Jay pointed out. I forgot how awesome a program it was and I've been playing with it.... While tracking Venus I saw it transit the sun and wondered how often that happens from Earth. The answer has me giving the Mayans some astronomical respect. The dates of Venus transit are: 1631, 1639... 1761, 1769... 1874, 1882... 2004, 2012NASA - 2004 and 2012 Transits of Venus About every 100 years there are two transits separated by eight earth years. It makes sense that eight years separate each set because: When a transit of Venus occurs, a second one often follows eight years later. This is because the orbital periods of Venus (224.701 days) and Earth (365.256 days) are in an 8 year (2922 days) resonance with each other. In other words, in the time it takes Earth to orbit the Sun eight times, Venus completes almost exactly thirteen revolutions about the Sun. As a result, Venus and Earth line up in the same positions with respect to the Sun. Actually, the two orbital periods are not quite commensurate with each other since Venus arrives at the eight year rendezvous about 22 hours earlier that Earth. By the third eight-year cycle, Venus arrives too early for a transit to occur.Catalog of Transits of Venus The Mayan calendar, then, is not far off from this (2922 days vs. 2920): [math]584*5=365*8=2920[/math] days in eight solar years and five synodic Venus periods And... I really thought I was on to something noticing that about 100 years separates the longer period between Venus transit sets. All three calendars (Venus 584 days, Haab 365 days, and tzolkin 260 days) sync up every 104 years: The ancient Maya tracked the morningstar risings of Venus, which occur every 584 days. Venus was the centerpiece of Mayan cosmology and mythology. They created a framework of cycles for predicting the future morningstar risings of Venus - for centuries to come. With this system, they could also predict solstice and eclipse dates. The two cycles involved in this "calendar" system were the vague year of 365 days (the haab) and the sacred cycle of 260 days (the tzolkin). These two cycles synchronize with each other every 52 years, and this period of time was known as the Calendar Round. The Venus cycle fits in nicely with multiples of the Calendar Round, such that all three cycles synchronize once every 104 years (2 Calendar Rounds). This was the Venus Round, and the sacred day which began the Venus Round was known as the Sacred Day of Venus.The Mayan Venus Calendar and the Golden Proportion But, the actual time between transet sets is 105.5 years or 121.5 years: The next transit season occurs either 105.5 years or 121.5 years later at the opposite node of Venus' orbit. Once again, a pair of transits will often occur separated by eight years. This recurrence pattern of 8 + 105.5 + 8 + 121.5 years can be seen repeating itself in the catalog of Venus transits.Catalog of Transits of Venus And, that is in addition to the 8 years, so that's not very close. That would have been really cool though if it ended up the Mayans were celebrating "the Sacred Day of Venus" every time Venus came back to a transect from a long absence. ~modest Quote
freeztar Posted September 24, 2009 Author Report Posted September 24, 2009 This had reminded me of Celestia, which Jay pointed out. I forgot how awesome a program it was and I've been playing with it.... While tracking Venus I saw it transit the sun and wondered how often that happens from Earth. The answer has me giving the Mayans some astronomical respect. They were indeed incredible astronomers. About every 100 years there are two transits separated by eight earth years. It makes sense that eight years separate each set because: Catalog of Transits of Venus Yep. It's pretty amazing they came up with a 365 day calendar. With a bit more time they may have figured out the extra 0.256 days a year, though I'm not sure if their mathematics even had fractions. :phones: The Mayan calendar, then, is not far off from this (2922 days vs. 2920):Indeed. And... I really thought I was on to something noticing that about 100 years separates the longer period between Venus transit sets. All three calendars (Venus 584 days, Haab 365 days, and tzolkin 260 days) sync up every 104 years: The Mayan Venus Calendar and the Golden Proportion But, the actual time between transet sets is 105.5 years or 121.5 years: Catalog of Transits of Venus And, that is in addition to the 8 years, so that's not very close. That would have been really cool though if it ended up the Mayans were celebrating "the Sacred Day of Venus" every time Venus came back to a transect from a long absence. ~modest Yeah, it would. I'm not aware that the Maya had any knowledge of Venus transits, or if they did the transits carried no significance for them. I'd have to play with the numbers, but maybe it's a consequence of not using fractions and sidereal vs. synodic measurements? :ideamaybenot? Quote
modest Posted September 24, 2009 Report Posted September 24, 2009 They were indeed incredible astronomers. Yeah. I know quite little about how ancient calendars work and even less about Mayan civilization, but I'm quickly coming to respect both and it's really interesting. Yep. It's pretty amazing they came up with a 365 day calendar. With a bit more time they may have figured out the extra 0.256 days a year, though I'm not sure if their mathematics even had fractions. ;) If they created the 365 day Haab around 550 BC and the Venus and Long Count not long after then I think they might have had plenty of time to figure out pretty accurately what kind of corrections they would need to make to calendar predictions in order to keep them in sync with astronomical observations. While the calendar itself gives no indication of that ability (i.e. they clearly didn't change the calendar), there is apparently evidence in the Dresden Codex that they could make the corrections, especially as it concerns Venus: Star gods of the Maya: astronomy in ... - Google Books Unless I'm misunderstanding the link :) Yeah, it would. I'm not aware that the Maya had any knowledge of Venus transits, or if they did the transits carried no significance for them. I'd have to play with the numbers, but maybe it's a consequence of not using fractions and sidereal vs. synodic measurements? :ideamaybenot? Yeah, I agree—they wouldn't have any way of observing or understanding a Venus transit. I'm sure it's an artifact of the transit being the least common multiple of an earth year and venus' synodic period just like their calendar. It would be pretty easy, I think, for an ancient culture to notice that Venus rises or sets on just about the same day of the year every 8 years. With about 1500 years for them to test the accuracy of the 584 and 365 day cycles compared to the position of Venus every 2920 days, I wouldn't be surprised if they knew with very good accuracy how much the calendar needed shifting over long periods of time to coincide with a Venus observation. I know a lot of ancient cultures were able to do the same with the moon and sun to predict lunar / solar transits: NASA - Eclipse 99 - Eclipses Through Traditions and Cultures But, this is all just so much speculation with the Mayans. ~modest Quote
freeztar Posted September 25, 2009 Author Report Posted September 25, 2009 I just typed a *huge* reply to this and it was lost when my connection was dropped and I reset my browser. ARGGHHH!!! I'll keep this one short as I don't have the patience right now to retype all of it (let alone remember everything I typed). Yeah. I know quite little about how ancient calendars work and even less about Mayan civilization, but I'm quickly coming to respect both and it's really interesting. (two long paragraphs compressed into...) Indeed. If they created the 365 day Haab around 550 BC and the Venus and Long Count not long after then I think they might have had plenty of time to figure out pretty accurately what kind of corrections they would need to make to calendar predictions in order to keep them in sync with astronomical observations. While the calendar itself gives no indication of that ability (i.e. they clearly didn't change the calendar), there is apparently evidence in the Dresden Codex that they could make the corrections, especially as it concerns Venus: Star gods of the Maya: astronomy in ... - Google Books Unless I'm misunderstanding the link :) Yeah, I agree—they wouldn't have any way of observing or understanding a Venus transit. I'm sure it's an artifact of the transit being the least common multiple of an earth year and venus' synodic period just like their calendar. It would be pretty easy, I think, for an ancient culture to notice that Venus rises or sets on just about the same day of the year every 8 years. With about 1500 years for them to test the accuracy of the 584 and 365 day cycles compared to the position of Venus every 2920 days, I wouldn't be surprised if they knew with very good accuracy how much the calendar needed shifting over long periods of time to coincide with a Venus observation. I know a lot of ancient cultures were able to do the same with the moon and sun to predict lunar / solar transits: NASA - Eclipse 99 - Eclipses Through Traditions and Cultures But, this is all just so much speculation with the Mayans. ~modest They fascinate me for their prowess with basic implements. Calculating the transits of lunar/solar is a lot easier than transits of Venus.Speculation is what makes the Maya so interesting. Damn, I can't believe I lost all that last post. It was huge and substantial. Oh well, I'll try to elaborate further when I'm not so p-ed off. ;) (Ctrl-A Ctrl-C and *then* submit)(Ctrl-A Ctrl-C and *then* submit)(Ctrl-A Ctrl-C and *then* submit)(Ctrl-A Ctrl-C and *then* submit)(Ctrl-A Ctrl-C and *then* submit)(Ctrl-A Ctrl-C and *then* submit)(Ctrl-A Ctrl-C and *then* submit)(Ctrl-A Ctrl-C and *then* submit) <sigh> Quote
hummingbird Posted August 31, 2010 Report Posted August 31, 2010 I must of gotten lost, the news side tracked me about two planets being found????? It reminds me of how we still use the groundhog :unsure: Your links just take me to the members list. Quote
Jay-qu Posted September 15, 2010 Report Posted September 15, 2010 Modest try stellarium for a free planetarium program - its my go to for all these sorts of questions. Another awesome astro program I use is google sky on Andriod or the iphone, you can hold it up to the sky and it will show you what is there with labels :) Thanks for the article Freezy :) and I feel your pain on loosing large replies.. I know type important posts into notepad first ;) Quote
Moontanman Posted September 16, 2010 Report Posted September 16, 2010 Freezy, have you ever seen Venus dance? First time I ever saw it dance around in the sky i was fascinated. I knew it had to be Venus, Venus was in that part of the sky but it danced around the sky across and area at least twice the size of the full moon, almost llike a light blinking in and out. it was of course due to the atmosphere distorting the image but it was an impressive sight. i wonder if ithe ancients ever recorded this observation of Venus and a distorted atmosphere? Quote
modest Posted September 17, 2010 Report Posted September 17, 2010 Modest try stellarium for a free planetarium program - its my go to for all these sorts of questions. Another awesome astro program I use is google sky on Andriod or the iphone, you can hold it up to the sky and it will show you what is there with labels :) Good info—thank you, Jay. I recently tried 'pocket universe' on iphone which was really sweet. I haven't seen google sky map on a mobal, but I'd bet it's about the same in setup and functionality. There really is a app for everything :) ~modest Quote
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