North Star Closer to Earth Than Thought

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posted on Dec, 17 2012 @ 02:18 AM
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Scientists Discover Nibiru is Heading This Way



OK, just kidding. Ignore the headline above.

Nibiru may be heading our way but scientists still haven't discovered it. Or should I say they haven't announced it ..... yet.


But they have announced that the North star is actually a lot closer than they used to think. Over 100 light years closer.

Link


The North Star has been a guiding light for countless generations of navigators. But a new study reveals that its distance to Earth may have been grossly overestimated.

In fact, the North Star—also called Polaris—is 30 percent closer to our solar system than previously thought, at about 323 light-years away, according to an international team who studied the star's light output.

Using Russia's 6-Meter Telescope, the researchers were able to calculate the North Star's distance from our solar system by analyzing its spectrum of light and obtaining data on its temperature and changes in intrinsic brightness over time.

That significantly revises the previously accepted value of 434 light-years, which was obtained by the European star-mapping satellite Hipparcos in the 1990s.



I wonder if the North Star is actually an alien space station flying toward us. If they have the technology to travel above the speed of light then they just might make it here by Dec. 21st.

The timing of this discovery is a little odd wouldn't you say?



OK, that was a joke too.


I thought this was worth sharing. Hope this hasn't been posted already. Cheers.
edit on 17-12-2012 by MagicWand67 because: (no reason given)




posted on Dec, 17 2012 @ 02:23 AM
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so Nibiru is closer than we thought, i knew it!!


Originally posted by MagicWand67

Scientists Discover Nibiru is Heading This Way




by almost a third!

so, what is it about the north star that is is so depended on in our sky, physically?

why is it so bright and so relatively fixed in our sky? does it have a constellation, and what else is known about it that is interesing?

and is the only breakthrough about the north star or were they wrong about other north star things in the past, too?



posted on Dec, 17 2012 @ 02:33 AM
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reply to post by minnow
 


All good questions.

I wish I could answer them for you.

Unfortunately this is not my area of expertise.

Maybe another member here can assist us.

Being that it is the closet star to us. I think that accounts for it's brightness.

edit on 17-12-2012 by MagicWand67 because: (no reason given)


en.wikipedia.org...


Polaris is the closest Cepheid variable to Earth so its physical parameters are of critical importance to the whole astronomical distance scale.[3] It is also the only one with a dynamically measured mass.
edit on 17-12-2012 by MagicWand67 because: (no reason given)



posted on Dec, 17 2012 @ 02:38 AM
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Ironic that you posted this.. A few hours ago a buddy and I were standing outside chit-chatting about random stuff.
We managed to turn the conversation to stars and whether or not they're dead and we just don't know yet. Then the north start was pointed out and something to the effect of, "If it has died, it's close enough to have an effect here."
Just speculation of course...

hmmm.. S&F



posted on Dec, 17 2012 @ 02:40 AM
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Originally posted by minnow
so Nibiru is closer than we thought, i knew it!!


Originally posted by MagicWand67

Scientists Discover Nibiru is Heading This Way




by almost a third!

so, what is it about the north star that is is so depended on in our sky, physically?

why is it so bright and so relatively fixed in our sky? does it have a constellation, and what else is known about it that is interesing?

and is the only breakthrough about the north star or were they wrong about other north star things in the past, too?


Great Find S&F to the OP, and here is a good link to answer some of the questions your post raised, for example the North Star is actually ranked #49 in brightness according to space.com



posted on Dec, 17 2012 @ 02:40 AM
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reply to post by MagicWand67
 


So if I was able to extend my life by about 4 times, and had a spaceship capable of light speed, I could reach the North Star if I dedicated my whole life to getting there.

Space is so big



posted on Dec, 17 2012 @ 02:46 AM
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reply to post by MagicWand67
 


It is amazing that we were off that much percentage wise and makes me think about what else we might not know for fact.

The article also states that they found other stars that appeared to be of a now defunct cluster and that there could be something still unseen orbiting around Polaris. Maybe that is Nibiru



posted on Dec, 17 2012 @ 02:53 AM
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Originally posted by MagicWand67

Maybe another member here can assist us.

Being that it is the closet star to us. I think that accounts for it's brightness.


i thought Centauri Proximus was our closest star?

was science mistaken and so now the North Star is our closest sun?



posted on Dec, 17 2012 @ 03:00 AM
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reply to post by minnow
 


Sorry, I told you this is not my area of expertise.

Let me correct that.

" Polaris is the closest Cepheid variable to Earth "

Whatever that means.



posted on Dec, 17 2012 @ 03:05 AM
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well i study this stuff so i can give you my opinion,
the Cepheid variable star is a class of stars that we use to gauge distence from a number of factors,

i wont go into the specifics but this discovery has implications to how we measure distance to other stars and galaxies

it works like this\\

we know how "bright" or luminous this star is and how its "pulse" changes over time, (variable)
by knowing the "type" of star and its expected luminosity we can equate distance.

keeping it simple here.

so this is the closest cephid variable to us and we use its characteristics as a "pattern"

this can be conceptualised as a ladder, and this star is the first rung on that distance ladder, we use it to judge where the second "rung" on the ladder is (cephid variable)

if our calculation of the first step (rung or star) in this ladder or distance calculation is out, then any and all subsequent distance calculations are incorrect and are compounding the error.

example,

if you were to look through binoculars backwards, and try to climb a ladder, the first step would look far away and you would reach out to touch it, but if you looked at the next step, it would look even further away than the first one did,

the further away the step the further away it would look.

if you extrapolate it out when we get to thousands of light years away from us these cephid varables would look to be very far away from us, but this is based on observations like luminosity, and the time it takes to "pulse"

if the first one has an incorrect distence calculation of 1/3,

then every cephid at a distence greater than the closest has an error factor that compounds with distance.

this truly is a great day in astrophysics.

i will read the article and return with a more precise description

xploder



posted on Dec, 17 2012 @ 03:10 AM
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reply to post by XPLodER
 


Thanks for that explanation.




posted on Dec, 17 2012 @ 03:13 AM
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This is insane, if they were wrong about this then what else have they miscalculated?

Its one of the most famous stars out there, used for navigation and such, I find it really weird that they messed it by as much as 33% - 100 light years! what!?! that's an awfully big miscalculation considering they recently photographed the furthest away Galaxy and claim to be able to tell how far away that is...



posted on Dec, 17 2012 @ 03:19 AM
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Originally posted by MagicWand67
reply to post by minnow
 


Sorry, I told you this is not my area of expertise.

Let me correct that.

" Polaris is the closest Cepheid variable to Earth "

Whatever that means.



The North Star's claim to fame is due to its fixed position in the sky for Northern Hemisphere observers—aligned with Earth's northern axis—while other stars appear to wheel around it.

Known to fade and brighten over a four-day period, this celestial beacon of true north is considered the closest and brightest member of a class of stars called Cepheids that change in brightness over time. (See star pictures.)

The star is also a type of cosmological yardstick used by researchers to measure great cosmic distances out to billions of light-years.

For this reason, it's vital for our understanding of the cosmos that scientists get a reliable grip on the North Star's true distance, emphasized Turner, whose study will appear in Astrophysical Journal Letters.

For instance, research on dark energy—the mysterious force thought to be causing the universe to fly apart faster over time—is dependent on stars such as the North Star.


news.nationalgeographic.com... m_content=link_fb20121217news-northstaricymi&utm_campaign=Content

measuring distance is one of the most difficult things to do in astophysics,
and is a science in of itself,

the basic idea here is that our missing mass calculations (dark matter) are based of data we calculate from this type of star.

by using "size" vs "luminosity" vs "colour" we can "plot" the star type on a chart


knowing these factors can help decide how big and bright and far a star is,

cephids are "variable" in there "luminosity" which makes them very valuable to use for distance calculations.

if the "closest" cephid variable was incorrectly measured or measured ion incorrect assumptions,

then so to must all other cephids we use as distance markers, to gauge distence past our galaxy.

"the galaxy may be closer than it appairs in the mirror of our telescopes"

off to do some more reading

THIS COULD BE BIG

xploder



posted on Dec, 17 2012 @ 03:37 AM
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Originally posted by MagicWand67
reply to post by XPLodER
 


Thanks for that explanation.



we need to get phage here,
me and phage have had a long running dispute about distance.

i have been saying since 2010 that our distance calculations are out,
and have authored many threads since 2010 trying to explain how and why our "perceived" view of the universe is incorrect.

the saying used in many of the debates was

object in the mirror may app-air further away than they acually are.

and in this case it proves to be acurite.



i was ....... correct about distance being closer, i wonder if i was correct about the cause of the error/

yay im having a scotch to celebrate.

xploder



posted on Dec, 17 2012 @ 07:52 AM
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There are different methods of measuring the distance to the stars. I'll try to explain a little of each.

1. Annual parallax. With parallax we measure the angle to the star when the earth is one position, and measure it again 6 months later, when the earth is on the opposite side of the sun. By simple trigonometry we can derive the distance to the star. The angles that we are talking about are extremely small and very difficult to measure. For example, the closest star, (and thus the star with the largest parallax), Proxima Centauri, has a parallax of 0.7687 ± 0.0003 arcsec. This angle is approximately equivalent to the parallax that you would get by measuring an object 2 centimeters in diameter located 5.3 kilometers away. Because these measurements are so small, we can only do these measurements for the very closest stars.



In 1989, the satelitte, Hipparcos, was launced that can do these measurements more accurate, and from its measurements the distance to Polaris could be calculated. The distance was calculated to be 434 light years.


This leads us to the question of how do we know the distance to stars that are further away?
By studying the closest stars, we assume that from what we know of stellar physics, that all stars of the same color, will be equally bright, if we view them at the same distance. This comes from stellar physics. We can place them in a graph, combining their luminosity(or absolute magnitude) and color. If we observe a new star, and measure it's color and apparent magnityde accurately, we can calculate how bright that star really is, from the inverse square law, and then we can calculate it's distance. This works, but only for stars that we can measure accurately.

Here is a picture of the graph, it is called the "Hertzsprung Russel Diagram"


If the star is further away, like in another galaxy, we can't do that anymore, so how do we meausure their distance?

By looking for special stars, and that is where Canopus comes in. It is a Cepheid variable, that is, it's brightness changes in a very fixed way. By studying a lot of Cepheid stars, astronomers discovered a strong relationship between their luminosity and the frequency of variability. Now, Cepheid stars are very bright, up to 100 000 times more luminous than our sun, se we can see them standing out from other stars in other galaxies. We can measure their apparent magnitude, and its period. From that we can calculate how bright it really is (absolute magnitude), and then we can calculate its distance.
typical cepheid variable:



Cepheid period vs. luminosity:


There are also different types of Cepheids, so it is not as simple as all that, but it is good enough for this explanation.

With Cepheids we can measure the distance to other galaxies in our local group. By using the Cepheid variables in the local galaxies, and measuring their red shifts, we can derive a value for Hubble's constant, and by using Hubble's constant, combined with the red shift to a distant galaxy, we can derive how far that distant galaxy is.


So, the fact that our distance to Polaris might be off, is of no concern to the average person. The distances to distant stars and galaxies have been redefined many times. Astronomy is a dynamic science. As we learn more, refine instrumentation more, develop more equipment, we learn more. Astronomy is like any other science, dynamic.

This is just a very short introduction on stellar distance measurements, will post more later, with references.

How far is that star?
www.ast.cam.ac.uk...
edit on 17/12/2012 by Hellhound604 because: Added HR, and cepheid graphs.
edit on 17/12/2012 by Hellhound604 because: (no reason given)
edit on 17/12/2012 by Hellhound604 because: (no reason given)
edit on 17/12/2012 by Hellhound604 because: (no reason given)



posted on Dec, 17 2012 @ 12:19 PM
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grrr, sorry, in my previous post I referred to Canopus. Don't know why I typed that, it should have been "Polaris", the pole star. Unfotunately my 4 hour edit period is over, so I cannot correct it there.



posted on Dec, 17 2012 @ 12:55 PM
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The claim of Turner et. al., that Polaris is 30% closer than indicated by the Hipparcos data is based on a different method of determining that distance. The article points out several clues that the Hipparcos calculations should have been suspect all along. It also points out that other, earlier (from the 1950s and 60s) calculations showed the distance to Polaris as being in agreement with theirs. Basically they are saying that the astronomers who determined the distance to Polaris from the Hipparcos data screwed up and probably should have realized it.

I'm sure this article will create a very lively discussion in the world of astrophysics but it doesn't really upset any apple carts concerning the distance other objects. It is about Polaris and Polaris alone and they haven't really figured that star out.
arxiv.org...
edit on 12/17/2012 by Phage because: (no reason given)



posted on Dec, 17 2012 @ 01:28 PM
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Originally posted by Phage
The claim of Turner et. al., that Polaris is 30% closer than indicated by the Hipparcos data is based on a different method of determining that distance. The article points out several clues that the Hipparcos calculations should have been suspect all along. It also points out that other, earlier (from the 1950s and 60s) calculations showed the distance to Polaris as being in agreement with theirs. Basically they are saying that the astronomers who determined the distance to Polaris from the Hipparcos data screwed up and probably should have realized it.

I'm sure this article will create a very lively discussion in the world of astrophysics but it doesn't really upset any apple carts concerning the distance other objects. It is about Polaris and Polaris alone and they haven't really figured that star out.
arxiv.org...
edit on 12/17/2012 by Phage because: (no reason given)


i had the understanding that polarus was used (closest to us) as an indicator of distance,
this info was then used as a "standard candle" of sorts that equated all subsequent cephids to these measurements,

if that IS the case this would cause distance calculations to in error, compounding over distance.
if all cephids are "modelled" of this (the most studied cephid in history) and luminosity/size for this class of star is interpreted or at the very least correlated with other stars of a similar nature,

does this not mean that we have an error compounding with distance?
is the Hubble constant not derived from these distance measurements?

and then the question of dark matter,
if objects are closer than they appair,
does this not effect the "dark matter equations"?

if our error is 1/3 at this distence,
what would the error be over a galactic distence scale?

xploder
if our cosmic ruler is incorrect,
that would effect the H/R diagram?

xploder



edit on 17-12-2012 by XPLodER because: (no reason given)



posted on Dec, 17 2012 @ 01:48 PM
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reply to post by XPLodER
 


i had the understanding that polarus was used (closest to us) as an indicator of distance, this info was then used as a "standard candle" of sorts that equated all subsequent cephids to these measurements,
Your understanding is wrong. Polaris is not used as a measuring stick.

The use of Cephid variables in determining distance is based on the discovery that for a given period of variability the star will have a given luminosity. By knowing the luminosity of the star, its distance can be determined (the farther away it is the less its apparent brightness, a direct calculation).

This article has refined the "typing" of Polaris and used that to determine its luminosity. It is from that luminosity that its distance was calculated.

outreach.atnf.csiro.au...
lcogt.net...
edit on 12/17/2012 by Phage because: (no reason given)



posted on Dec, 17 2012 @ 02:47 PM
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Originally posted by Phage
reply to post by XPLodER
 


i had the understanding that polarus was used (closest to us) as an indicator of distance, this info was then used as a "standard candle" of sorts that equated all subsequent cephids to these measurements,
Your understanding is wrong. Polaris is not used as a measuring stick.

interesting



The use of Cephid variables in determining distance is based on the discovery that for a given period of variability the star will have a given luminosity. By knowing the luminosity of the star, its distance can be determined (the farther away it is the less its apparent brightness, a direct calculation).


squared distence law, but if such a close star is "less" luminous than thought (closer) then that would mean that either it is not as reliable as though to equate "type/size" to luminosity over distance as previously thought.
this would put other stars position into question?

in this case either the star was less luminous, or a different size? and if we cant accurately be sure of either (one has to be in question) then the "expected" luminosity size equation is wrong.

if we can be wrong at these close distance scales "how can we be sure of acuricy at greater distances"?



This article has refined the "typing" of Polaris and used that to determine its luminosity. It is from that luminosity that its distance was calculated.

so its a change in size/luminosity? or star type?

outreach.atnf.csiro.au...
lcogt.net...
edit on 12/17/2012 by Phage because: (no reason given)


ps thanks for the links

xploder





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