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Will Earth pass through the galactic plane in 2012?
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There's been much hoopla about the winter solstice sun aligning with the galactic plane on December 21, 2012.
11-20-2009 - space
According to the computational wizard Jean Meeus (page 301-303 of Mathematical Astronomy Morsels), the solstice points were in alignment with the galactic equator as recently as the year 1998.
In other words, the 2012 alignment isn’t unique. Consider the view from our local star, the sun. As seen from the sun, Earth crosses the Milky Way’s galactic plane (also called the galactic equator) twice a year, every year.
Or consider the view from Earth. As seen from Earth, the sun crosses the galactic plane – also called the galactic equator on our sky – twice a year, every year. All of this is just part of Earth’s normal motion, as projected on our sky’s dome, as we travel around the sun. Quite by coincidence, the ecliptic – the projection of the Earth’s orbital plane onto the stellar sphere – intersects the galactic plane near the solstice points. That’s why these points are so near each other on our sky’s dome.
However, it’s true that the sun on the December solstice doesn’t return to the same exact spot in front of the backdrop stars every year. The solstice point slowly but surely moves westward through the stars at about one degree per every 72 years. (For reference, the sun’s diameter equals about 1/2 degree.)
Therefore, the solstice point moves about 30 degrees westward every 2,160 years. By the year 2269, the December solstice point will cross into the constellation Ophiuchus. Then the solstices won’t happen so near the location of the galactic plane in our sky.
Take a look at our sky chart. If you could see the stars during the daytime, you’d see the sun in front of the constellation Sagittarius on each December 21 solstice. We show Sagittarius as a Teapot on this sky chart, because many people are able to see that pattern. On or near each December solstice, the sun crosses the plane of the Milky Way galaxy above the spout of the Teapot, a bit north of the galactic center. Can you see that intersection? Also look for the various M-objects along the galactic equator, as shown on our chart. Those are star clusters in the star-crowded plane of the galaxy.
Related:
Where is the ecliptic in relation to the Milky Way?
Written by Bruce McClure
Comments (22)
at 8.17 pm on 10-03-2009 Derek
I think this "2012" hypothesis is another example of the human brain trying to make order out of chaos- we can't help but look for some kind of pattern in all the "noise" of the cosmos-
I think either we will end our existence by our own stupidity/ignorance, or an outside force will decide our fate for us. If it happens to be on Dec. 21, 2012, it would be the ultimate coincidence, or "art" imitating life....
Replyat 10.43 am on 10-05-2009 Steve Jones
This article talks about the apparent view of the solstice points from the earth or from the sun etc. This is not relevant to what is being said about the 2012 period. What i have been told is that the cycle being described by the Mayan long-count relates to the Solar system as an object relative to the disk of the galaxy. The idea is that our solar system is moving in orbit around the galactic center in such a way that it wobbles up and down through the plane of the galactic disk every (whatever) number of years.
The apparent view from this or that location is not a relevent aspect of the discussion.
Replyat 06.46 am on 10-06-2009 Bruce McClure
Hi Steve.
Yes, I concur with you. As the sun orbits the galactic center in an estimated 230 million years, the sun (and solar sytem) bob up then down through the galactic plane in periods of roughly 35 million years. From the accounts that I have read, the solar system now lies several dozen light-years north of the galactic plane. (To see scientific abstracts that give various estimates for the sun's distance from the galactic plane, do a Google search, typing in: sun, distance from galactic plane.) It's my understanding that the sun is moving away from the galactic plane at some 7 kilometers per second, and won't start its descent toward the plane of our Milky Way galaxy for millions of years to come.
Bruce
at 4.27 pm on 10-09-2009 NOYB
Stupid. there will be no end you crazy fools it is just a end to a calender LOL
Replyat 4.29 pm on 10-09-2009 NOYB
oh, and we MIGHT go extinct in 50 billion years. 2012 is not 50billion years from now.
at 06.34 am on 10-12-2009 Bruce McClure
NOYB,
Yes, it seems that some people think the end of the Mayan Baktun cycle on the winter solstice, 2012, spells out doomsday for our planet. I'm not so sure this is what the Mayan had in mind. The end point of the Baktun cycle is akin to the odometer of a car turning over and displaying a line of zeros. However, the sun is expected to swell into a red giant in about 5 billion years, and that will probably mean real doomsday for the planet.
As a reminder, EarthSky encourages civil dialogue, and does not tolerate name-calling. We all have something to gain from respectful conversation.
Bruce
at 08.00 am on 11-01-2009 bostondude82
I don't know about you, but I was told that when my car's odometer flips over and reaches zero, it'll explode.
at 11.14 pm on 11-19-2009 Bibelson Biliveskok
what happened to the Neanderthals to the dinosaur and the deserts once where green belts.... what happens up in the sky.........where it ends........how many stars........what is a cell man made of .....how the cell grow ......what is energy.....No answer...... believe in our ignorance....before we claim our credibilities.......!!!!
at 12.22 pm on 10-11-2009 Bruce Marchand
Are their gravitational forces responsible for our solar system bobbing 'up then down through the galactic plane in periods of roughly 35 million years' ? Can dark matter encourage or reduce this bobbing effect?
Replyat 04.46 am on 10-12-2009 Bruce McClure
Bruce,
I don't really know what forces are at work to make our solar system pass through the galactic plane every 35 or so million years. Try submitting your question to an astronomer at Cornell University at http://curious.astro.cornell.edu/.
Goood luck!
Bruce
at 10.15 pm on 10-14-2009 Silverthaw
I am looking for an interactive model of our solar and galactic system in 3D. One that can be looked at from all angles with time shifts and movement that correlates to times and dates. I want to see not just the distances and positions of planets in regards to the sun and each other on a flat plane but all the planes and intersections. I need something with depth. I hope I explained this right. Can't seem to find one online on my own.
Replyat 06.52 am on 10-15-2009 Bruce McClure
Silverthaw,
For starters, try your luck with the 'Where is M13' software at http://www.thinkastronomy.com/M13/index.html. For some perspective on the size of our Milky Way galaxy, consider this: if we shrunk the solar system out to the orbit of Pluto to the size of a quarter, the Milky Way would be the size of North America.
Bruce
at 1.09 pm on 11-21-2009 Jennifer Wood
Some one in the bog said that (according to some astronomers) the solar system and sun is now several dozen light years away from the galactic plane and still moving away from it. Others have claimed some astronomers have said that the sun and solar system began passing thru the galactic plane in 1998, peaked in about 2007 and will be done passing thru it by 2016. Can you comment on this? Do you know where this second account may be coming from and what it might be referring to?
Replyat 08.12 am on 11-23-2009 Bruce McClure
Jennifer,
All scientific abstracts with which I am familiar claim the solar system is north of the galactic plane. Furthermore, the solar system will continue to travel north of the galactic plane for millions of years to come.
According to the computational wizard, Jean Meeus, the solstice points were in alignment with the galactic equator (plane) in 1998. However, since the sun is a disk and not a point, I suppose you could say that a portion of the December solstice sun will align with the galactic equator (plane) for a period of about 36 years, centered on 1998. That represents the period from about 1980-2016.
When speaking of the December solstice sun aligning with the galactic equator (plane), we're talking about the position of the sun relative to the background stars, as seen from Earth. That does not mean that we physically pass through the galactic plane each year on the December solstice.
The plane of Earth's orbit around the sun is inclined by about 60 degrees to the plane of the galactic equator. Go outside sometime with a Hula-Hoop. Stick your head through the middle of this Hula-Hoop and tilt it about 60 degrees to your horizon. Your head represents the sun and the Hula-Hoop represents the Earth's orbit. The landscape you are standing on all the way to the horizon depicts the galactic plane. Note that the Hula-Hoop appears to cross the horizon at two points. These two points are analogous to the solstice points aligning with the galactic equator (plane). Of course, the Hula-Hoop isn't physically passing through the horizon at these two points of alignment. Similarly, the Earth isn't physically passing through the galactic plane on the solstices.
Bruce
at 1.22 pm on 11-21-2009 Jennifer Wood
I meant to say "blog" but perhaps "bog" can be the new name for all the confusion bogging down the facts surrounding the 2012 "event." (Astronomers, Mayan calendars, ancient oracles, and prophetic hacks the world over have got the cataclysmic date all wrong: it is 2010, the year Oprah Winfrey is ending her show.) For those of you with SGDS [sarcastic gene deficiency syndrome]: JUST KIDDING!
Replyat 1.28 pm on 11-21-2009 Jennifer Wood
I meant 2011. (If only others were as good as me at constantly reporting their own inaccuracies what a world it would be.)
SGDS people: just ignore the comment.
Replyat 04.17 am on 12-10-2009 Mr. Middle
I'm a skeptical mystic, here are few important points:
The moment of sunrise was very important to 'the ancients' very real mystical reasons.
On 12/21/2012 @ 11:11AM GMT the Sun will cross the winter solstice point precisely *at sunrise* as viewed from Mesoamerica.
Astronomers say the Winter Solstice point crossed the galactic equator in 1998 but they admit that there is a slight margin of error on the galactic scale. It is possible that the Mayans knew the rising Sun will align with Winter Solstice *and* the Galactic Equator on 12/21/2012.
There is indeed *one* ancient specific reference to the date 12.21.2012, it is on a stone in Mesoamerica, Tortuguero Monument 6.
The Mayan Tzolk'in calendar does not end in 2012, it is only the beginning of the next cycle but one stone does in fact say 'something' will happen.
Unfortunately, the word on the monument that describes exactly what will happen is effaced.
From David Stuart's recent decipherment of Tortuguero Monument 6 for the UT Mesoamerican Google group:
As promised here's a quick translation of the final passage* of
Tortuguero Monument 6, recording the 2012 Bak'tun ending:
Tzuhtz-(a)j-oom u(y)-uxlajuun pik
(ta) Chan Ajaw ux(-te') Uniiw.
Uht-oom ?
Y-em(al)?? Bolon Yookte' K'uh ta ?.
"The Thirteenth 'Bak'tun" will be finished
(on) Four Ajaw, the Third of Uniiw (K'ank'in). (12.21.2012)
? will occur. (indecipherable)
(It will be) the descent(??) of the Nine Support? God(s) to the ?."
All new-age woo-woo aside there is an authentic, albeit vague, prophecy.
Replyat 09.09 am on 12-10-2009 Bruce McClure
Hi Mr. Middle,
The Mayan prophecy - if, indeed, there is one - might be vague. But there's nothing vague about the statement that "On 12/21/2012 @ 11:11AM GMT the Sun will cross the winter solstice point precisely at sunrise as viewed from Mesoamerica." Are you suggesting that the Mayans predicted the time of the northern hemisphere's 2012 winter solstice to the minute? Looking up "Mesoamerica" in the Random House Websters's Unabridged Dictionary (second edition), I find this as the first definition: the area extending approximately from central Mexico to Honduras and Nicaragua in which diverse pre-Columbian civilizations flourished. As far as I can tell, the sun will still be below the horizon in Mesoamerica at precisely 11:11AM Universal Time on 12/21/2012.
Bruce
at 7.32 pm on 01-03-2010 Bob
The Maya never came up with a wheel, but we think they can predict the end of the world.......
Replyat 1.12 pm on 01-22-2010 BassHero
So if theres all this evidence that the world will not end in 2012, which upon i believe in, why do people put videos on Youtube.com saying we will die with catastrophic events e.g. Weather, Planet-X, Oracles and etc.. Where they getting there evidence from? and is it true? because i'm on the border line sort of about this whole hypothesis.
James
Replyat 09.52 am on 01-25-2010 Bruce McClure
BassHero,
Although I take it for granted that 1+1=2, the mathematicians Alfred North Whitehead and Bertrand Russell came up with an elaborate proof of the fact in their book Principia Mathematica. In like vein, I'm taking it for granted that our planet Earth will be around not only tomorrow, but on and after December 21, 2012, because I haven't yet seen what I consider to be any credible evidence to the contrary.
Bruce
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at 8.17 pm on 10-03-2009 Derek
I think this "2012" hypothesis is another example of the human brain trying to make order out of chaos- we can't help but look for some kind of pattern in all the "noise" of the cosmos-
I think either we will end our existence by our own stupidity/ignorance, or an outside force will decide our fate for us. If it happens to be on Dec. 21, 2012, it would be the ultimate coincidence, or "art" imitating life....
at 10.43 am on 10-05-2009 Steve Jones
This article talks about the apparent view of the solstice points from the earth or from the sun etc. This is not relevant to what is being said about the 2012 period. What i have been told is that the cycle being described by the Mayan long-count relates to the Solar system as an object relative to the disk of the galaxy. The idea is that our solar system is moving in orbit around the galactic center in such a way that it wobbles up and down through the plane of the galactic disk every (whatever) number of years.
The apparent view from this or that location is not a relevent aspect of the discussion.
at 06.46 am on 10-06-2009 Bruce McClure
Hi Steve.
Yes, I concur with you. As the sun orbits the galactic center in an estimated 230 million years, the sun (and solar sytem) bob up then down through the galactic plane in periods of roughly 35 million years. From the accounts that I have read, the solar system now lies several dozen light-years north of the galactic plane. (To see scientific abstracts that give various estimates for the sun's distance from the galactic plane, do a Google search, typing in: sun, distance from galactic plane.) It's my understanding that the sun is moving away from the galactic plane at some 7 kilometers per second, and won't start its descent toward the plane of our Milky Way galaxy for millions of years to come.
Bruce
at 4.27 pm on 10-09-2009 NOYB
Stupid. there will be no end you crazy fools it is just a end to a calender LOL
at 4.29 pm on 10-09-2009 NOYB
oh, and we MIGHT go extinct in 50 billion years. 2012 is not 50billion years from now.
at 06.34 am on 10-12-2009 Bruce McClure
NOYB,
Yes, it seems that some people think the end of the Mayan Baktun cycle on the winter solstice, 2012, spells out doomsday for our planet. I'm not so sure this is what the Mayan had in mind. The end point of the Baktun cycle is akin to the odometer of a car turning over and displaying a line of zeros. However, the sun is expected to swell into a red giant in about 5 billion years, and that will probably mean real doomsday for the planet.
As a reminder, EarthSky encourages civil dialogue, and does not tolerate name-calling. We all have something to gain from respectful conversation.
Bruce
at 08.00 am on 11-01-2009 bostondude82
I don't know about you, but I was told that when my car's odometer flips over and reaches zero, it'll explode.
at 11.14 pm on 11-19-2009 Bibelson Biliveskok
what happened to the Neanderthals to the dinosaur and the deserts once where green belts.... what happens up in the sky.........where it ends........how many stars........what is a cell man made of .....how the cell grow ......what is energy.....No answer...... believe in our ignorance....before we claim our credibilities.......!!!!
at 12.22 pm on 10-11-2009 Bruce Marchand
Are their gravitational forces responsible for our solar system bobbing 'up then down through the galactic plane in periods of roughly 35 million years' ? Can dark matter encourage or reduce this bobbing effect?
Replyat 04.46 am on 10-12-2009 Bruce McClure
Bruce,
I don't really know what forces are at work to make our solar system pass through the galactic plane every 35 or so million years. Try submitting your question to an astronomer at Cornell University at http://curious.astro.cornell.edu/.
Goood luck!
Bruce
at 10.15 pm on 10-14-2009 Silverthaw
I am looking for an interactive model of our solar and galactic system in 3D. One that can be looked at from all angles with time shifts and movement that correlates to times and dates. I want to see not just the distances and positions of planets in regards to the sun and each other on a flat plane but all the planes and intersections. I need something with depth. I hope I explained this right. Can't seem to find one online on my own.
Replyat 06.52 am on 10-15-2009 Bruce McClure
Silverthaw,
For starters, try your luck with the 'Where is M13' software at http://www.thinkastronomy.com/M13/index.html. For some perspective on the size of our Milky Way galaxy, consider this: if we shrunk the solar system out to the orbit of Pluto to the size of a quarter, the Milky Way would be the size of North America.
Bruce
at 1.09 pm on 11-21-2009 Jennifer Wood
Some one in the bog said that (according to some astronomers) the solar system and sun is now several dozen light years away from the galactic plane and still moving away from it. Others have claimed some astronomers have said that the sun and solar system began passing thru the galactic plane in 1998, peaked in about 2007 and will be done passing thru it by 2016. Can you comment on this? Do you know where this second account may be coming from and what it might be referring to?
Replyat 08.12 am on 11-23-2009 Bruce McClure
Jennifer,
All scientific abstracts with which I am familiar claim the solar system is north of the galactic plane. Furthermore, the solar system will continue to travel north of the galactic plane for millions of years to come.
According to the computational wizard, Jean Meeus, the solstice points were in alignment with the galactic equator (plane) in 1998. However, since the sun is a disk and not a point, I suppose you could say that a portion of the December solstice sun will align with the galactic equator (plane) for a period of about 36 years, centered on 1998. That represents the period from about 1980-2016.
When speaking of the December solstice sun aligning with the galactic equator (plane), we're talking about the position of the sun relative to the background stars, as seen from Earth. That does not mean that we physically pass through the galactic plane each year on the December solstice.
The plane of Earth's orbit around the sun is inclined by about 60 degrees to the plane of the galactic equator. Go outside sometime with a Hula-Hoop. Stick your head through the middle of this Hula-Hoop and tilt it about 60 degrees to your horizon. Your head represents the sun and the Hula-Hoop represents the Earth's orbit. The landscape you are standing on all the way to the horizon depicts the galactic plane. Note that the Hula-Hoop appears to cross the horizon at two points. These two points are analogous to the solstice points aligning with the galactic equator (plane). Of course, the Hula-Hoop isn't physically passing through the horizon at these two points of alignment. Similarly, the Earth isn't physically passing through the galactic plane on the solstices.
Bruce
at 1.22 pm on 11-21-2009 Jennifer Wood
I meant to say "blog" but perhaps "bog" can be the new name for all the confusion bogging down the facts surrounding the 2012 "event." (Astronomers, Mayan calendars, ancient oracles, and prophetic hacks the world over have got the cataclysmic date all wrong: it is 2010, the year Oprah Winfrey is ending her show.) For those of you with SGDS [sarcastic gene deficiency syndrome]: JUST KIDDING!
Replyat 1.28 pm on 11-21-2009 Jennifer Wood
I meant 2011. (If only others were as good as me at constantly reporting their own inaccuracies what a world it would be.)
SGDS people: just ignore the comment.
at 04.17 am on 12-10-2009 Mr. Middle
I'm a skeptical mystic, here are few important points:
The moment of sunrise was very important to 'the ancients' very real mystical reasons.
On 12/21/2012 @ 11:11AM GMT the Sun will cross the winter solstice point precisely *at sunrise* as viewed from Mesoamerica.
Astronomers say the Winter Solstice point crossed the galactic equator in 1998 but they admit that there is a slight margin of error on the galactic scale. It is possible that the Mayans knew the rising Sun will align with Winter Solstice *and* the Galactic Equator on 12/21/2012.
There is indeed *one* ancient specific reference to the date 12.21.2012, it is on a stone in Mesoamerica, Tortuguero Monument 6.
The Mayan Tzolk'in calendar does not end in 2012, it is only the beginning of the next cycle but one stone does in fact say 'something' will happen.
Unfortunately, the word on the monument that describes exactly what will happen is effaced.
From David Stuart's recent decipherment of Tortuguero Monument 6 for the UT Mesoamerican Google group:
As promised here's a quick translation of the final passage* of
Tortuguero Monument 6, recording the 2012 Bak'tun ending:
Tzuhtz-(a)j-oom u(y)-uxlajuun pik
(ta) Chan Ajaw ux(-te') Uniiw.
Uht-oom ?
Y-em(al)?? Bolon Yookte' K'uh ta ?.
"The Thirteenth 'Bak'tun" will be finished
(on) Four Ajaw, the Third of Uniiw (K'ank'in). (12.21.2012)
? will occur. (indecipherable)
(It will be) the descent(??) of the Nine Support? God(s) to the ?."
All new-age woo-woo aside there is an authentic, albeit vague, prophecy.
at 09.09 am on 12-10-2009 Bruce McClure
Hi Mr. Middle,
The Mayan prophecy - if, indeed, there is one - might be vague. But there's nothing vague about the statement that "On 12/21/2012 @ 11:11AM GMT the Sun will cross the winter solstice point precisely at sunrise as viewed from Mesoamerica." Are you suggesting that the Mayans predicted the time of the northern hemisphere's 2012 winter solstice to the minute? Looking up "Mesoamerica" in the Random House Websters's Unabridged Dictionary (second edition), I find this as the first definition: the area extending approximately from central Mexico to Honduras and Nicaragua in which diverse pre-Columbian civilizations flourished. As far as I can tell, the sun will still be below the horizon in Mesoamerica at precisely 11:11AM Universal Time on 12/21/2012.
Bruce
at 7.32 pm on 01-03-2010 Bob
The Maya never came up with a wheel, but we think they can predict the end of the world.......
Replyat 1.12 pm on 01-22-2010 BassHero
So if theres all this evidence that the world will not end in 2012, which upon i believe in, why do people put videos on Youtube.com saying we will die with catastrophic events e.g. Weather, Planet-X, Oracles and etc.. Where they getting there evidence from? and is it true? because i'm on the border line sort of about this whole hypothesis.
James
at 09.52 am on 01-25-2010 Bruce McClure
BassHero,
Although I take it for granted that 1+1=2, the mathematicians Alfred North Whitehead and Bertrand Russell came up with an elaborate proof of the fact in their book Principia Mathematica. In like vein, I'm taking it for granted that our planet Earth will be around not only tomorrow, but on and after December 21, 2012, because I haven't yet seen what I consider to be any credible evidence to the contrary.
Bruce