Rotation of our solar system and....

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worthj1970

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Relative to the rotation of the galaxy, do we rotate in the same plane?
 
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newtonian

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I second that question - in fact, I just asked it in other words on the north up thread!<br /><br />I doubt it is exact, btw. but earth's equator varies about a mean (average) that is close to the plane of the solar system eccliptic- albeit the axis of rotation is tilted (which is why we have seasons).<br /><br />I know we periodically pass throught the galactic arm which is on the galactic eccliptic. <br /><br />And I might add to your question:<br /><br />Does the Milky Way also rotate (compare revolve) counterclockwise when looking from North down?
 
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newtonian

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worthj1970 - by 'we' do you mean earth or the solar system?<br /><br />I assume you are not personally rotating! <br /><br />[Edit - I removed my inaccurate description of earth's equanoxes - see Calli's accurate description]<br /><br />The other planet's rotational axis are angled slighly compared with the solar system eccliptic. [Mercury is zero?]
 
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Saiph

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No, we don't. We're pretty cockeyed compared to it. Not only are we tipped (like something spinning with a tilt on table) but we're also off in the other 2 rotational dimensions.<br /><br />I.e. we're all wonky. I might dig up some details later. <div class="Discussion_UserSignature"> <p align="center"><font color="#c0c0c0"><br /></font></p><p align="center"><font color="#999999"><em><font size="1">--------</font></em></font><font color="#999999"><em><font size="1">--------</font></em></font><font color="#999999"><em><font size="1">----</font></em></font><font color="#666699">SaiphMOD@gmail.com </font><font color="#999999"><em><font size="1">-------------------</font></em></font></p><p><font color="#999999"><em><font size="1">"This is my Timey Wimey Detector.  Goes "bing" when there's stuff.  It also fries eggs at 30 paces, wether you want it to or not actually.  I've learned to stay away from hens: It's not pretty when they blow" -- </font></em></font><font size="1" color="#999999">The Tenth Doctor, "Blink"</font></p> </div>
 
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CalliArcale

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<blockquote><font class="small">In reply to:</font><hr /><p>BTW - earth's equator exactly lines up with the plane of the solar system eccliptic twice a year, at the equanoxes- which are when spring and fall begin, about March 21 and September 21.<br /><br />Then again, that is by definition - the other planet's revolution are angled slighly compared with the solar system eccliptic.<p><hr /></p></p></blockquote><br /><br />Actually, the Earth equator always bisects the ecliptic. This is because the ecliptic is defined by the plane of the Earth's orbit, which means the Earth has an orbital inclination of exactly 0 degrees. Other planets are inclined (slightly or severely; Mars is 1.85 degrees but Pluto is a whopping 17.15), so they cross the ecliptic twice each year. These events are <i>not</i> equinoxes (though pure coincidence could leave a planet with an equinox at this time), but are called plane crossings. It's the time when they pass through the imaginary plane described by the ecliptic.<br /><br />An equinox is something different. It is when the northern and southern hemispheres of a planet receive identical amounts of sunlight. If a planet's rotational axis is inclined relative to the plane of its orbit (not the plane of the ecliptic), each pole will see sunlight for only part of the year, experiencing midnight sun in the middle of summer and sunless "days" in the middle of the winter. Earth's arctic and antarctic circles are defined by the lowest latitude which experiences midnight sun.<br /><br />So, if you were the Sun looking at the Earth, the time of the equinox would occur when the plane of the Earth's equator passes through you. (That plane is not aligned with the ecliptic, however. It is always inclined relative to the orbital plane, because the axis is inclined, and the equator's plane is perpendicular to that -- so the equator is inclined by the axial inclination plus ninety degrees.) If you're standing on the Earth, the equinox occurs when the Sun rises due <div class="Discussion_UserSignature"> <p> </p><p><font color="#666699"><em>"People assume that time is a strict progression of cause to effect, but actually from a non-linear, non-subjective viewpoint it's more like a big ball of wibbly wobbly . . . timey wimey . . . stuff."</em>  -- The Tenth Doctor, "Blink"</font></p> </div>
 
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pizzaguy

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You know, this is the 'umpteenth' one of these kinds of threads. You guys are making my head hurt.<br />.<br />.<br />.<br />.<br />.<br />.<br />... Oh, wait. I have an axe planted in my head - THAT'S why it hurts.<br /><br />But, anyway, life was SO much easier before the renaissance, when we were at the center of creation and the 'heavens' were 'painted' on crystal spheres.<br /><br />But, it all doesn't matter, I belive in the flat earth .<br /><br /> <div class="Discussion_UserSignature"> <font size="1"><em>Note to Dr. Henry:  The testosterone shots are working!</em></font> </div>
 
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mooware

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It's hard to believe people still think the Earth is flat. Are these people for real, or is it some kind of parody?<br /><br />
 
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pizzaguy

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Hard to tell - there was a guy who died in CA in 2001 that SEEMED serious. He had a monthly newletter with circulation in the thousands, but that doesn't mean he BELIEVED it. <br /><br />I dont think there are any of them left - but that link was funny, and I wasn't sure about them until I read this:<br /><font color="yellow"><br /><b><br />20. Does Idaho exist<br /> No. The existence of Idaho is a lie, fabricated by a conspiracy of cartographers, as is England (see question 10).<br /><br />21. What about North Dakota?<br /> That doesn't exist either.<br /><br />22. Any other places which are believed to exist but really don't?<br /> Yes, Australia. And then there are the cryptogeographica, places such as Kadath, Carcosa, Hobbiton, Narnia, Hy-Brasil, Hell and such whose existence has not been satisfactorily proven.</b> <br /></font><br />But, even THEY got THAT wrong. I'v been to Hell, it's just north of Ann Arbor <div class="Discussion_UserSignature"> <font size="1"><em>Note to Dr. Henry:  The testosterone shots are working!</em></font> </div>
 
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mooware

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Well, undoubtedly some fool will believe it. Folks can be quite stupid.<br /><br />As far as the Flat Earth link goes, it must be a satire. Kind of like the site that wants to shutdown Landover baptist church. That one has an "onion" type feel to it.<br /><br /> I drove through Michigan last year. I should have stopped by hell and said hell-o<br />
 
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igorsboss

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Pizzaguy, what about the Flat Earth's crust?<br /><br />Deep dish or hand-tossed?
 
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Saiph

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actually, the flat earth society is a mix of both. The # of people legitimately members is probably the minority.<br /><br />There <i>are</i> people out there who think it's flat though. I've met two. and another who argued it just to be difficult (unfortunately for him, I know what I'm talking about...:) ) <div class="Discussion_UserSignature"> <p align="center"><font color="#c0c0c0"><br /></font></p><p align="center"><font color="#999999"><em><font size="1">--------</font></em></font><font color="#999999"><em><font size="1">--------</font></em></font><font color="#999999"><em><font size="1">----</font></em></font><font color="#666699">SaiphMOD@gmail.com </font><font color="#999999"><em><font size="1">-------------------</font></em></font></p><p><font color="#999999"><em><font size="1">"This is my Timey Wimey Detector.  Goes "bing" when there's stuff.  It also fries eggs at 30 paces, wether you want it to or not actually.  I've learned to stay away from hens: It's not pretty when they blow" -- </font></em></font><font size="1" color="#999999">The Tenth Doctor, "Blink"</font></p> </div>
 
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tom_hobbes

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The site FAQ is compiled by 'Lee Harvey Oswald Smith'. <img src="/images/icons/smile.gif" /><br /><br />Entertaining stuff.<br /><br />I like some of the minor details in the site. Like the green skinned women. Reminds me of an old legend, 'The Green Children Of Woolpit'. I've been to Woolpit a number of times for my work, but never seen any. <img src="/images/icons/smile.gif" /><br /><br />http://www.llewellyn.com/archive/fate/175/<br /><br />http://www.feralchildren.com/en/pager.php?df=carey <div class="Discussion_UserSignature"> <p><font size="2" color="#339966"> I wish I could remember<br /> But my selective memory<br /> Won't let me</font><font size="2" color="#99cc00"> </font><font size="3" color="#339966"><font size="2">- </font></font><font size="1" color="#339966">Mark Oliver Everett</font></p><p> </p> </div>
 
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mooware

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<font color="yellow">"Pizzaguy, what about the Flat Earth's crust? <br /><br />Deep dish or hand-tossed?"</font><br /><br />How about stuffed crust?<br /><br />
 
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newtonian

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Calli - Thank you for correcting me. I was repeating what I read without checking with a mental picture of what is actually happening at the equanox.<br /><br />I will edit my wrong above post accordingly.<br /><br />Sorry about that.<br /><br />So that means north on earth is always at the same angle compared with north in the solar system eccliptic?
 
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Saiph

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yep <div class="Discussion_UserSignature"> <p align="center"><font color="#c0c0c0"><br /></font></p><p align="center"><font color="#999999"><em><font size="1">--------</font></em></font><font color="#999999"><em><font size="1">--------</font></em></font><font color="#999999"><em><font size="1">----</font></em></font><font color="#666699">SaiphMOD@gmail.com </font><font color="#999999"><em><font size="1">-------------------</font></em></font></p><p><font color="#999999"><em><font size="1">"This is my Timey Wimey Detector.  Goes "bing" when there's stuff.  It also fries eggs at 30 paces, wether you want it to or not actually.  I've learned to stay away from hens: It's not pretty when they blow" -- </font></em></font><font size="1" color="#999999">The Tenth Doctor, "Blink"</font></p> </div>
 
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newtonian

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Saiph - Wow! That is a revelation to me! Yet, I guess I already knew that from past study - but it didn't register, if you know what I mean.<br /><br />So that brings us full circle (pun) back to the original posted question.<br /><br />And, by extension, does this mean that the north rotational pole of earth always points to the same place in space [for example, a candidate for a Hubble deep field]?<br /><br />Or does the revolution in the Milky Way eccliptic make this variable?<br /><br />Does this mean that the north rotati
 
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Saiph

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The earth, via gyroscopic stabilization (read conservation of angular momentum, or "like a top") maintains a 23.5 degree axial tilt compared to the plane of the solar system (i.e. suns equatorial plane).<br /><br />We don't deviate from that for the same reason a top doesn't tip over.<br /><br />You'll also notice on tops, is that the angle you set them spinning at, they tend to stay at. This is demonstrated most dramatically when you spin up a bike wheel vertically, and hang it from an axel. The bike wheel won't fall down (so that the wheel now spins horizontally).<br /><br />Now, as the earth goes about the sun, it will point in the same direction. If it was pointed "left" that tilt will always be to the "left" as it orbits the sun.<br /><br />Back to the wheel. You will notice that does does rotate about the pivot point (even though it doesn't fall horizontal). The wheel goes around in a circle, about the verticle string. That's called precession. This, makes my last statement a small lie.<br /><br />The earth precesses, because the forces acting upon it (most notably the moon and sun) aren't balanced.<br /><br />So while the earth always remains tilted 23.5 degrees (i.e. points the same way relative to the solar system plane) where it points isn't always the same spot. Slowly but surely the earth shifts from pointing left, to "right" and back again. This, however, takes 26,000 years. So it's not a biggie (though it has ofset the original alignment of egyptian pryamids and causes astronomers to update the starmaps every 50 years or so).<br /><br />As far as the stars we're pointed at moving due to our motion through the galaxy, or thier own proper motion...that takes a lot longer (with only a few exceptions 2 maybe?) <div class="Discussion_UserSignature"> <p align="center"><font color="#c0c0c0"><br /></font></p><p align="center"><font color="#999999"><em><font size="1">--------</font></em></font><font color="#999999"><em><font size="1">--------</font></em></font><font color="#999999"><em><font size="1">----</font></em></font><font color="#666699">SaiphMOD@gmail.com </font><font color="#999999"><em><font size="1">-------------------</font></em></font></p><p><font color="#999999"><em><font size="1">"This is my Timey Wimey Detector.  Goes "bing" when there's stuff.  It also fries eggs at 30 paces, wether you want it to or not actually.  I've learned to stay away from hens: It's not pretty when they blow" -- </font></em></font><font size="1" color="#999999">The Tenth Doctor, "Blink"</font></p> </div>
 
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newtonian

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Saiph - OK, so - taking precession into account, how would the angle differ from 1500 BCE to the present?<br /><br />Also, what is the limit of angle change during the wobble of precession?
 
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Saiph

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1500 years? It's still tilted 23.5 degrees. However it's been rotated about it's circle by 3500/26000 * 360 degrees: Or 48.5 degrees around the circle. (~15 %) <div class="Discussion_UserSignature"> <p align="center"><font color="#c0c0c0"><br /></font></p><p align="center"><font color="#999999"><em><font size="1">--------</font></em></font><font color="#999999"><em><font size="1">--------</font></em></font><font color="#999999"><em><font size="1">----</font></em></font><font color="#666699">SaiphMOD@gmail.com </font><font color="#999999"><em><font size="1">-------------------</font></em></font></p><p><font color="#999999"><em><font size="1">"This is my Timey Wimey Detector.  Goes "bing" when there's stuff.  It also fries eggs at 30 paces, wether you want it to or not actually.  I've learned to stay away from hens: It's not pretty when they blow" -- </font></em></font><font size="1" color="#999999">The Tenth Doctor, "Blink"</font></p> </div>
 
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newtonian

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Saiph - Thank you. <br /><br />The circle would be the wobble of precession?<br /><br />What is this circle exactly-i.e. what are the limits?<br /><br />I.e., not the portion of the circle (48.5 degrees of 360 degrees) of wobble, but rather the angle from present north that this would translate as?<br />
 
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newtonian

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You all - Concerning precession, a slight tangent is that this falsifies a basis for astrology. In reading the following, you will note that the articles stress the westward motion of precession, not north or south - is there a logical reason for this?<br /><br />Because of "precession of the equinoxes," which is caused by a slight "wobble" of the earth as it rotates on its axis, the sun now crosses the equator each spring in the constellation called Pisces instead of Aries. This puts traditional astrology charts that give dates for the sun to pass through the twelve constellations of the zodiac a full section out of alignment.<br /><br />"The inference from this is clear," remarks Christopher McIntosh in The Astrologers and Their Creed. "Either the astrological tradition became obsolete as soon as the precession began to affect the alignment of signs and constellations, or else the qualities attributed to the signs are not connected with the stars at all."- "Awake!," 8/8/75, p. 4.<br /><br />The World Book Encyclopedia explains why:<br />"Each year, the sun crosses the equator about 50 seconds of arc west of the points where it crossed the year before. This westward movement of the equinoctial points is called the precession of the equinoxes. . . .<br /><br />"Because of precession, the signs of the zodiac no longer correspond to the constellations for which they were named. Over 2,000 years ago the sun was in the part of the sky called Aries at the spring equinox, and it is still called the first of Aries. It is now in the constellation Pisces, and is moving on toward the constellation which is called Aquarius in the zodiac." - quoted in "Awake!," 11/22/73 p. 5.
 
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Saiph

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The earth will always be tilted 23.5 degrees from the ecliptic pole (i.e. it's tilted compared to the sun's pole). This link has a couple of useful illustrations.<br /><br />http://astro.wsu.edu/worthey/astro/html/lec-precession.html<br /><br /><br />The reason the precession is westward, not northward, is simple: THe pole never points further "north" (compared to sun), it instead stays just as tilte, but rotates about the axis.<br /><br />Hopefully the diagrams help cement things together. <div class="Discussion_UserSignature"> <p align="center"><font color="#c0c0c0"><br /></font></p><p align="center"><font color="#999999"><em><font size="1">--------</font></em></font><font color="#999999"><em><font size="1">--------</font></em></font><font color="#999999"><em><font size="1">----</font></em></font><font color="#666699">SaiphMOD@gmail.com </font><font color="#999999"><em><font size="1">-------------------</font></em></font></p><p><font color="#999999"><em><font size="1">"This is my Timey Wimey Detector.  Goes "bing" when there's stuff.  It also fries eggs at 30 paces, wether you want it to or not actually.  I've learned to stay away from hens: It's not pretty when they blow" -- </font></em></font><font size="1" color="#999999">The Tenth Doctor, "Blink"</font></p> </div>
 
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newtonian

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crazyeddie- Yes, it is a tangent- but a relevant one.<br /><br />Saiph -the link states Vega will be the North star in the distant future.<br /><br />Where is Vega compared with Polaris and the Big Dipper?<br /><br />The link also states that earth's rotational axis tilt varies<br />"about plus or minus 1.3 degrees from its average value of 23.3 degrees."<br />Is Vega within 2.6 degrees of Polaris in the celestial hemisphere?<br /><br />
 
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Saiph

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it passes directly overhead at sunset right about now (the bright guy straight up).<br /><br /><br />Vega is quite a way's away from polaris, but it lies on the large circle the pole scribes in the sky. The width of that circle, is 2.6 degrees (this minor variation is called nutation). <div class="Discussion_UserSignature"> <p align="center"><font color="#c0c0c0"><br /></font></p><p align="center"><font color="#999999"><em><font size="1">--------</font></em></font><font color="#999999"><em><font size="1">--------</font></em></font><font color="#999999"><em><font size="1">----</font></em></font><font color="#666699">SaiphMOD@gmail.com </font><font color="#999999"><em><font size="1">-------------------</font></em></font></p><p><font color="#999999"><em><font size="1">"This is my Timey Wimey Detector.  Goes "bing" when there's stuff.  It also fries eggs at 30 paces, wether you want it to or not actually.  I've learned to stay away from hens: It's not pretty when they blow" -- </font></em></font><font size="1" color="#999999">The Tenth Doctor, "Blink"</font></p> </div>
 
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nexium

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Likely most of yor posts are correct, however, I think the 23 degrees tilt of Earth is with respect to the plane of the ecliptic which is the path of Earth's orbit around the Sun. The pole of the sun is also tilted about 20 degrees with respect to the plane of Earth's orbit around the Sun The Sun's path around the galaxy is tilted about 33? degrees with respect to the plane of Ecliptic. Please correct, refute, embellish or comment. Neil
 
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