Hi I am new here and I was doing some research and happened to look at "A briefer history of time" by Stephen Hawking.
There was a chapter on expanding universe , Hubble made a huge contribution to this and so did Hippolyte Fizeau with his Doppler shift.Hubble claimed (when he measured the light from distant galaxies) that most (more than blue) were red shift, indicating that most were moving away from the location of the observer and observations BUT some were blue, also indicating that most were moving towards the location of observation thus more was moving away, and less was coming towards.
Light travels at the speed of light, and is not that much when in comparison to the vast distance of relative objects in space thus, light takes time to get here, by using Snell's law, you can find the distance a star is by knowing its intensity, but even OUR sun who's light takes eight minutes to get here (well, when you look at it, you are looking 8 minutes into the past) and its ONLY 149 million kilometers away, which isn't much in comparison with the HUGE AND VAST distance of space.
If that is so, could that be that most of our calculations (I=1/d^2) of distances of light emitting objects be wrong having known that he also stated that the the more far a light emitting celestial object was the faster it moved away?
causing our calculations to be even MORE wrong?
The way the universe expands is that the distance between galaxies grows, and becomes bigger, they move away from each other, then how is it that the distance between celestial objects inside the galaxies grows(as in stars and planets)?
Which brings us to yet another problem, why is it that Hubble found more redshifts and less blue ones?
more celestial objects are moving away from earth (from a source)?
well, Thank you, kind regards
Sandra Doliak
Mmmgh’ I don’t know how bad the dark matter problem is?
Does this mean that there is a dark matter conspiracy and dark matter is pushing every galaxy away from every other galaxy, at an alarming rate?
Or,. Do the state of things appear this way?
Does this mean that there is a dark matter conspiracy and dark matter is pushing every galaxy away from every other galaxy, at an alarming rate?
Or,. Do the state of things appear this way?
QUOTE (Sandra doliak+Mar 26 2008, 03:18 AM)
If that is so, could that be that most of our calculations (I=1/d^2) of distances of light emitting objects be wrong having known that he also stated that the the more far a light emitting celestial object was the faster it moved away?
causing our calculations to be even MORE wrong?
Are you sure that's what was said? Astronomers use Type 1a supernovae as "standard candles" because they all release roughly the same amount of light. The less light we see, the further away we assume the supernova to be. And usually the dimmer the supernova, the higher the redshift of the host galaxy.
causing our calculations to be even MORE wrong?
Are you sure that's what was said? Astronomers use Type 1a supernovae as "standard candles" because they all release roughly the same amount of light. The less light we see, the further away we assume the supernova to be. And usually the dimmer the supernova, the higher the redshift of the host galaxy.
hello Sandra doliak 
snells law is not a preferred way to measure astronomical distances. the method of determining distance depends on the distance you want to measure and what the object is. parallax is good for relatively close objects, but as the distance becomes literally astronomical parallax is no good as the apparent motion become more and more difficult to detect. you then need to change the method to those that use luminosity relationships like the cepheid method.
snells law is not a preferred way to measure astronomical distances. the method of determining distance depends on the distance you want to measure and what the object is. parallax is good for relatively close objects, but as the distance becomes literally astronomical parallax is no good as the apparent motion become more and more difficult to detect. you then need to change the method to those that use luminosity relationships like the cepheid method.
why is it that Hubble found more redshifts and less blue ones?
because there are more objects further away then close to us.
i can not remember which specific cluster it is to use as an example (but virgo sounds right), but a cluster of galaxies have a average redshift value, even thought a few of the individual galaxies in the cluster have a blue shift. what is happening is the galaxies are orbiting the centre of gravity and some are moving toward us and some away, but the expansion of space component of the total redshift, which moves the entire cluster away from the milky way, overwhelms any blueshift component.
Spin can be one way =red shifting light, while the other way= blue shifting light
Galactic spin alters the frequency of light, and it seems that like matter and anti-matter
galactic spin has a preferred direction ..it is anisotropic
now add
Spin can be one way =red shifting light, while the other way= blue shifting light
Galactic spin alters the frequency of light, and it seems that like matter and anti-matter
galactic spin has a preferred direction ..it is anisotropic
now add
there is an existing "noncosmological redshift"
Just leaving a light source causes a red shift... the bigger the light source the greater the red shift
(experiments have been carried out on Earth... light leaving the ground is red shifted, light falling to the ground is blue shifted)
so it is not hard to understand that the Universe is not expanding at all, and therefore there never was a Big Bang
Oh, and AFAIK, Hubble was not really responsible for all the Big bang nonsense.
QUOTE
Sandra doliak Posted on Today at 1:18 PM by using Snell's law,
snells law is not a preferred way to measure astronomical distances. the method of determining distance depends on the distance you want to measure and what the object is. parallax is good for relatively close objects, but as the distance becomes literally astronomical parallax is no good as the apparent motion become more and more difficult to detect. you then need to change the method to those that use luminosity relationships like the cepheid method.
QUOTE (->
| QUOTE |
| Sandra doliak Posted on Today at 1:18 PM by using Snell's law, |
snells law is not a preferred way to measure astronomical distances. the method of determining distance depends on the distance you want to measure and what the object is. parallax is good for relatively close objects, but as the distance becomes literally astronomical parallax is no good as the apparent motion become more and more difficult to detect. you then need to change the method to those that use luminosity relationships like the cepheid method.
why is it that Hubble found more redshifts and less blue ones?
because there are more objects further away then close to us.
i can not remember which specific cluster it is to use as an example (but virgo sounds right), but a cluster of galaxies have a average redshift value, even thought a few of the individual galaxies in the cluster have a blue shift. what is happening is the galaxies are orbiting the centre of gravity and some are moving toward us and some away, but the expansion of space component of the total redshift, which moves the entire cluster away from the milky way, overwhelms any blueshift component.
Sandra,
You're absolutely right to question the basis for these measurements. As you mention even a slight miscalculation in a term would result in a major discrepancy in the result when we're talking about these sorts of huge distances.
One of the major questioners of this whole Cephied/Standard Candle measurement process is a guy called Geoffrey Burbridge who points out that there is an existing "noncosmological redshift" that isn't taken into account (i.e... they're "redder" to begin with). Additionally, there are probabilities that absorption by the intergalactic medium (whatever it is) could have a major effect.
When the "standard candle" you are using as a basis for your measurement is already in another galaxy it would seem to me that depending on it to (and there are assumptions about their apparent luminosity --- or it wouldn't be called "apparent") measure other more distant bodies then the veracity of your results has got to be questionable.
It's somewhat funny to me (and I've really only discovered all this information in the last six months) that so many many cosmologists have this seeming blind acceptance of a principle that could have some serious flaws.
Hubble's assistant didn't believe that his doppler measurements could/should be used to measure galactic distances.
As a layman I like to think that the measurements are wrong and that the Universe is substantially smaller and ironically VASTLY older than such measurements lead us to believe.
You're absolutely right to question the basis for these measurements. As you mention even a slight miscalculation in a term would result in a major discrepancy in the result when we're talking about these sorts of huge distances.
One of the major questioners of this whole Cephied/Standard Candle measurement process is a guy called Geoffrey Burbridge who points out that there is an existing "noncosmological redshift" that isn't taken into account (i.e... they're "redder" to begin with). Additionally, there are probabilities that absorption by the intergalactic medium (whatever it is) could have a major effect.
When the "standard candle" you are using as a basis for your measurement is already in another galaxy it would seem to me that depending on it to (and there are assumptions about their apparent luminosity --- or it wouldn't be called "apparent") measure other more distant bodies then the veracity of your results has got to be questionable.
It's somewhat funny to me (and I've really only discovered all this information in the last six months) that so many many cosmologists have this seeming blind acceptance of a principle that could have some serious flaws.
Hubble's assistant didn't believe that his doppler measurements could/should be used to measure galactic distances.
As a layman I like to think that the measurements are wrong and that the Universe is substantially smaller and ironically VASTLY older than such measurements lead us to believe.
I have recently seen a great many programs describing a problem we have in explaining the increasing speed of the expansion of our universe . They proposed to explain this phenomena by introducing a new energy or the combination of “Dark Matter” and a proposed “Dark Energy” .
These programs were admittedly simplified for public consumption and may have failed to describe the attributes and function of this dark energy with any accuracy.
Pondering what this could be and how it relates to our knowledge of how nature or reality works.
It occurred to me that we could have examples of this energy in our understanding of interactions of matter and gas within a vacuum.
We have discovered that any gas filled envelope exposed to a vacuum will expand to its maximum contained volume. In addition we know that if the container is punctured the gas will escape and continue to expand till it has equalized the pressure of its molecular structure within the volume of the vacuum it resides in.
I think we have been misinterpreting what we see and attempting to describe something new that attracts matter and gas. This new something surrounds and envelops our universe and imparts this motive force to our galactic expansion.
Could it be we are misidentifying or conjuring monsters where there need be none. Could it simply be a difference in pressure that drives this expansion.
I propose that the pure vacuum volume of our universe is greater than the the gaseous molecular pressure within the visible universe. Thus providing the force for expansion as internal pressure is attempting to expand to fill the available space and will continue till this equilibrium is reached.
If this is the case then we should be able to model this and even calculate the total volume of our universe or at least the volume of pure vacuum remaining to expand within .
These programs were admittedly simplified for public consumption and may have failed to describe the attributes and function of this dark energy with any accuracy.
Pondering what this could be and how it relates to our knowledge of how nature or reality works.
It occurred to me that we could have examples of this energy in our understanding of interactions of matter and gas within a vacuum.
We have discovered that any gas filled envelope exposed to a vacuum will expand to its maximum contained volume. In addition we know that if the container is punctured the gas will escape and continue to expand till it has equalized the pressure of its molecular structure within the volume of the vacuum it resides in.
I think we have been misinterpreting what we see and attempting to describe something new that attracts matter and gas. This new something surrounds and envelops our universe and imparts this motive force to our galactic expansion.
Could it be we are misidentifying or conjuring monsters where there need be none. Could it simply be a difference in pressure that drives this expansion.
I propose that the pure vacuum volume of our universe is greater than the the gaseous molecular pressure within the visible universe. Thus providing the force for expansion as internal pressure is attempting to expand to fill the available space and will continue till this equilibrium is reached.
If this is the case then we should be able to model this and even calculate the total volume of our universe or at least the volume of pure vacuum remaining to expand within .
I have recently seen a great many programs describing a problem we have in explaining the increasing speed of the expansion of our universe . They proposed to explain this phenomena by introducing a new energy or the combination of “Dark Matter” and a proposed “Dark Energy” .
These programs were admittedly simplified for public consumption and may have failed to describe the attributes and function of this dark energy with any accuracy.
Pondering what this could be and how it relates to our knowledge of how nature or reality works.
It occurred to me that we could have examples of this energy in our understanding of interactions of matter and gas within a vacuum.
We have discovered that any gas filled envelope exposed to a vacuum will expand to its maximum contained volume. In addition we know that if the container is punctured the gas will escape and continue to expand till it has equalized the pressure of its molecular structure within the volume of the vacuum it resides in.
I think we have been misinterpreting what we see and attempting to describe something new that attracts matter and gas. This new something surrounds and envelops our universe and imparts this motive force to our galactic expansion.
Could it be we are misidentifying or conjuring monsters where there need be none. Could it simply be a difference in pressure that drives this expansion.
I propose that the pure vacuum volume of our universe is greater than the the gaseous molecular pressure within the visible universe. Thus providing the force for expansion as internal pressure is attempting to expand to fill the available space and will continue till this equilibrium is reached.
If this is the case then we should be able to model this and even calculate the total volume of our universe or at least the volume of pure vacuum remaining to expand within .
These programs were admittedly simplified for public consumption and may have failed to describe the attributes and function of this dark energy with any accuracy.
Pondering what this could be and how it relates to our knowledge of how nature or reality works.
It occurred to me that we could have examples of this energy in our understanding of interactions of matter and gas within a vacuum.
We have discovered that any gas filled envelope exposed to a vacuum will expand to its maximum contained volume. In addition we know that if the container is punctured the gas will escape and continue to expand till it has equalized the pressure of its molecular structure within the volume of the vacuum it resides in.
I think we have been misinterpreting what we see and attempting to describe something new that attracts matter and gas. This new something surrounds and envelops our universe and imparts this motive force to our galactic expansion.
Could it be we are misidentifying or conjuring monsters where there need be none. Could it simply be a difference in pressure that drives this expansion.
I propose that the pure vacuum volume of our universe is greater than the the gaseous molecular pressure within the visible universe. Thus providing the force for expansion as internal pressure is attempting to expand to fill the available space and will continue till this equilibrium is reached.
If this is the case then we should be able to model this and even calculate the total volume of our universe or at least the volume of pure vacuum remaining to expand within .
I think that red and blue shifts, have the same relative pressure behind them.
Light is not mass, however pressure and energy.
The problem with Hubble lengths in very distant galaxies, is what the scope sees, isn’t actually happening.
This is a slant variable in reality, as another process is going on behind what your viewing.
So this brings us back to the question, what value is light, from distant stars, if the utility of that light cannot be valued?
Light is not mass, however pressure and energy.
The problem with Hubble lengths in very distant galaxies, is what the scope sees, isn’t actually happening.
This is a slant variable in reality, as another process is going on behind what your viewing.
So this brings us back to the question, what value is light, from distant stars, if the utility of that light cannot be valued?
QUOTE
why is it that Hubble found more redshifts and less blue ones?
Spin can be one way =red shifting light, while the other way= blue shifting light
Galactic spin alters the frequency of light, and it seems that like matter and anti-matter
galactic spin has a preferred direction ..it is anisotropic
now add
QUOTE (->
| QUOTE |
| why is it that Hubble found more redshifts and less blue ones? |
Spin can be one way =red shifting light, while the other way= blue shifting light
Galactic spin alters the frequency of light, and it seems that like matter and anti-matter
galactic spin has a preferred direction ..it is anisotropic
now add
there is an existing "noncosmological redshift"
Just leaving a light source causes a red shift... the bigger the light source the greater the red shift
(experiments have been carried out on Earth... light leaving the ground is red shifted, light falling to the ground is blue shifted)
so it is not hard to understand that the Universe is not expanding at all, and therefore there never was a Big Bang
Oh, and AFAIK, Hubble was not really responsible for all the Big bang nonsense.
QUOTE (uaafanblog+Mar 27 2008, 10:48 PM)
Sandra,
You're absolutely right to question the basis for these measurements. As you mention even a slight miscalculation in a term would result in a major discrepancy in the result when we're talking about these sorts of huge distances.
One of the major questioners of this whole Cephied/Standard Candle measurement process is a guy called Geoffrey Burbridge who points out that there is an existing "noncosmological redshift" that isn't taken into account (i.e... they're "redder" to begin with). Additionally, there are probabilities that absorption by the intergalactic medium (whatever it is) could have a major effect.
When the "standard candle" you are using as a basis for your measurement is already in another galaxy it would seem to me that depending on it to (and there are assumptions about their apparent luminosity --- or it wouldn't be called "apparent") measure other more distant bodies then the veracity of your results has got to be questionable.
It's somewhat funny to me (and I've really only discovered all this information in the last six months) that so many many cosmologists have this seeming blind acceptance of a principle that could have some serious flaws.
Hubble's assistant didn't believe that his doppler measurements could/should be used to measure galactic distances.
As a layman I like to think that the measurements are wrong and that the Universe is substantially smaller and ironically VASTLY older than such measurements lead us to believe.
Hubble said Red shifted galaxies aren't simply "moving" away from each other, they are actually accelerating away, though the acceleration is very slow.
The relative motion of galaxies clusters that are far enough away as to not be affected significantly by the local group's gravity are moving away from us at velocity found by:
72/km/s/megaparsec.
The distance between celestial objects actually does expand,its just that this expansion is so small you can't observe it because gravity quickly masks it. The expansion between one side of the milkyway and the opposite is almost insignificant. Megaparsec is one million parsecs. Parsec is 3.6 ly. So galaxy "tries" to expand at a rate of 2km/s across its diameter, But the galactic mass is so great that this expansion would be very diffiicult to detect. AT least that would be the interpretation.
So that is hubble's theory.
-----
The big problem I have with using apparant magnitude and luminosities of objects is that its circular reasoning. Identifying a supernova's type from a distant galaxy or from a far edge of our own galaxy is pure guesswork.
I=1/d^2
In any inverse square law, the term "d^2" or "r^2" (for gravity) is measured in meters. this denominator grows ABSURDLY large with astronomical distances.
Here are some examples.
ly = 9.4608*10^15m
Sun
d = 1.5*10^11m
I = 1/ 2.25*10^22
Closest star
d = 3.6 ly
I = 1/1.16*10^33 (100 million times smaller than the sun)
Center of Milkyway
d = ~29,000ly
I = 1/7.5275*10^40 (ten million times less than closest star)
Opposite edge of milky way
d = ~79,000ly
I = 1/ 5.586*10^41
Andromeda Galaxy
d = ~2.1*10^22m
I = 1/4.41*10^44 (ten thousand times less than center of milkyway)
VArious inter- Galactic ranges
d= 10,000,000 ly
I = 1/ 8.9506*10^45 (20 times less than andromeda)
---
d= 100,000,000ly
I = 1/ 8.9506*10^47 (2000 times less than andromeda)
----
d = 1,000,000,000ly (one billion)
I = 1/ 8.9506*10^49 (200,000 times less than andromeda)
---
d = 10,000,000,000ly
I = 1/ 8.9506*10^51 (20 million times less than andromeda)
---
d = ~13,700,000,000ly (farthest observed objects, allegedly)
I = 1/ 1.6799*10^52 (about 100million times less than andromeda)
--------
As stated, given these progressions, identifying the type of object or explosion you are looking at is guesswork. The variables involved are:
relative velocity
relative acceleration
mass of the star
composition of the star
age of the star
distance
space dust
apparant magnitude
Hubble said Red shifted galaxies aren't simply "moving" away from each other, they are actually accelerating away, though the acceleration is very slow.
The relative motion of galaxies clusters that are far enough away as to not be affected significantly by the local group's gravity are moving away from us at velocity found by:
72/km/s/megaparsec.
The distance between celestial objects actually does expand,its just that this expansion is so small you can't observe it because gravity quickly masks it. The expansion between one side of the milkyway and the opposite is almost insignificant. Megaparsec is one million parsecs. Parsec is 3.6 ly. So galaxy "tries" to expand at a rate of 2km/s across its diameter, But the galactic mass is so great that this expansion would be very diffiicult to detect. AT least that would be the interpretation.
So that is hubble's theory.
-----
The big problem I have with using apparant magnitude and luminosities of objects is that its circular reasoning. Identifying a supernova's type from a distant galaxy or from a far edge of our own galaxy is pure guesswork.
I=1/d^2
In any inverse square law, the term "d^2" or "r^2" (for gravity) is measured in meters. this denominator grows ABSURDLY large with astronomical distances.
Here are some examples.
ly = 9.4608*10^15m
Sun
d = 1.5*10^11m
I = 1/ 2.25*10^22
Closest star
d = 3.6 ly
I = 1/1.16*10^33 (100 million times smaller than the sun)
Center of Milkyway
d = ~29,000ly
I = 1/7.5275*10^40 (ten million times less than closest star)
Opposite edge of milky way
d = ~79,000ly
I = 1/ 5.586*10^41
Andromeda Galaxy
d = ~2.1*10^22m
I = 1/4.41*10^44 (ten thousand times less than center of milkyway)
VArious inter- Galactic ranges
d= 10,000,000 ly
I = 1/ 8.9506*10^45 (20 times less than andromeda)
---
d= 100,000,000ly
I = 1/ 8.9506*10^47 (2000 times less than andromeda)
----
d = 1,000,000,000ly (one billion)
I = 1/ 8.9506*10^49 (200,000 times less than andromeda)
---
d = 10,000,000,000ly
I = 1/ 8.9506*10^51 (20 million times less than andromeda)
---
d = ~13,700,000,000ly (farthest observed objects, allegedly)
I = 1/ 1.6799*10^52 (about 100million times less than andromeda)
--------
As stated, given these progressions, identifying the type of object or explosion you are looking at is guesswork. The variables involved are:
relative velocity
relative acceleration
mass of the star
composition of the star
age of the star
distance
space dust
apparant magnitude
It's somewhat funny to me (and I've really only discovered all this information in the last six months) that so many many cosmologists have this seeming blind acceptance of a principle that could have some serious flaws.
I've always said this same thing, but people treat you like a dumbass just for questioning anything that a "scientist" says.
They use an assumption about distance to determine how bright or massive an object is. Then they turn around and use this number to determine how far away another object is. Its circular reasoning based almost entirely on assumptions.
this is nonsense. it is either it expands or it does not expand. if it expands at 2km/s and the milky way is approx 13billion years old, do the math, the milky way would not be its current size.
this is nonsense. it is either it expands or it does not expand. if it expands at 2km/s and the milky way is approx 13billion years old, do the math, the milky way would not be its current size.
They use an assumption about distance to determine how bright or massive an object is
it is not an assumption, it is a simple relation
no. "they" use different methods eg luminosity and parallax, on nearby stars and if these different methods yield comparable results then "they" have more confidence in saying "star A is too distant for parallax to work, but since parallax and luminosity yield same results on nearby stars, luminosity must work by itself for distant objects"
it seems you have assumed you understand this topic.
the SPACE-TIME in the region expands, but GRAVITY is stronger than 2km/s expansion. Do the math.
Space-time expansion and "objects moving apart" are not necesssarily one and the same if those objects are close enough for gravity to overcome the rate of expansion.
the SPACE-TIME in the region expands, but GRAVITY is stronger than 2km/s expansion. Do the math.
Space-time expansion and "objects moving apart" are not necesssarily one and the same if those objects are close enough for gravity to overcome the rate of expansion.
no. "they" use different methods eg luminosity and parallax, on nearby stars and if these different methods yield comparable results then "they" have more confidence in saying "star A is too distant for parallax to work, but
it seems you have assumed you understand this topic.
I think we know what parallax is in principle.
its comparing apparant angles to a star at different times of the year and then using geometry to try to calculate the distance.
But the angles are so small that this is just laughable.
closest star
4.04*10^16m
Earth orbital diameter
3*10^11m
But no, it is not proper to make the same assumption about distant objects.
"Nearby stars" aren't really nearby at all.
Do you even know how small the change in angle of an object would really be at 4.04*10^16m distance across a 6 month period?
The change in angle is so small, even for the absolute closest stars in the sky, that the margine of any number of human errors or instrumentation errors completely renders the measurement useless. And this is for the CLOSEST stars.
Its
7.426*10^-6 degrees
You can't even make that measurement because the earth is spinning fast enough that you can't even focus a telescope to within that degree of accuracy fast enough to make a measurement.
I have an auto aligning telescope that cost a couple hundred dollars, and I know that's nothing compared to professional observatories, but the point is, anyone who has actually tried to look at the stars with a telescope knows what I'm talking about. They actually are not easy to keep in the crosshairs even with a computer autocalculating and moving the telescope for you, much less make parallax measurements where the first significant digit is the 6th decimal place.
Compared to the numbers astronomers throw around, 4-5 ly is absolutely nothing.
You're absolutely right to question the basis for these measurements. As you mention even a slight miscalculation in a term would result in a major discrepancy in the result when we're talking about these sorts of huge distances.
One of the major questioners of this whole Cephied/Standard Candle measurement process is a guy called Geoffrey Burbridge who points out that there is an existing "noncosmological redshift" that isn't taken into account (i.e... they're "redder" to begin with). Additionally, there are probabilities that absorption by the intergalactic medium (whatever it is) could have a major effect.
When the "standard candle" you are using as a basis for your measurement is already in another galaxy it would seem to me that depending on it to (and there are assumptions about their apparent luminosity --- or it wouldn't be called "apparent") measure other more distant bodies then the veracity of your results has got to be questionable.
It's somewhat funny to me (and I've really only discovered all this information in the last six months) that so many many cosmologists have this seeming blind acceptance of a principle that could have some serious flaws.
Hubble's assistant didn't believe that his doppler measurements could/should be used to measure galactic distances.
As a layman I like to think that the measurements are wrong and that the Universe is substantially smaller and ironically VASTLY older than such measurements lead us to believe.
QUOTE
If that is so, could that be that most of our calculations (I=1/d^2) of distances of light emitting objects be wrong having known that he also stated that the the more far a light emitting celestial object was the faster it moved away?
causing our calculations to be even MORE wrong?
The way the universe expands is that the distance between galaxies grows, and becomes bigger, they move away from each other, then how is it that the distance between celestial objects inside the galaxies grows(as in stars and planets)?
causing our calculations to be even MORE wrong?
The way the universe expands is that the distance between galaxies grows, and becomes bigger, they move away from each other, then how is it that the distance between celestial objects inside the galaxies grows(as in stars and planets)?
Hubble said Red shifted galaxies aren't simply "moving" away from each other, they are actually accelerating away, though the acceleration is very slow.
The relative motion of galaxies clusters that are far enough away as to not be affected significantly by the local group's gravity are moving away from us at velocity found by:
72/km/s/megaparsec.
The distance between celestial objects actually does expand,its just that this expansion is so small you can't observe it because gravity quickly masks it. The expansion between one side of the milkyway and the opposite is almost insignificant. Megaparsec is one million parsecs. Parsec is 3.6 ly. So galaxy "tries" to expand at a rate of 2km/s across its diameter, But the galactic mass is so great that this expansion would be very diffiicult to detect. AT least that would be the interpretation.
So that is hubble's theory.
-----
The big problem I have with using apparant magnitude and luminosities of objects is that its circular reasoning. Identifying a supernova's type from a distant galaxy or from a far edge of our own galaxy is pure guesswork.
I=1/d^2
In any inverse square law, the term "d^2" or "r^2" (for gravity) is measured in meters. this denominator grows ABSURDLY large with astronomical distances.
Here are some examples.
ly = 9.4608*10^15m
Sun
d = 1.5*10^11m
I = 1/ 2.25*10^22
Closest star
d = 3.6 ly
I = 1/1.16*10^33 (100 million times smaller than the sun)
Center of Milkyway
d = ~29,000ly
I = 1/7.5275*10^40 (ten million times less than closest star)
Opposite edge of milky way
d = ~79,000ly
I = 1/ 5.586*10^41
Andromeda Galaxy
d = ~2.1*10^22m
I = 1/4.41*10^44 (ten thousand times less than center of milkyway)
VArious inter- Galactic ranges
d= 10,000,000 ly
I = 1/ 8.9506*10^45 (20 times less than andromeda)
---
d= 100,000,000ly
I = 1/ 8.9506*10^47 (2000 times less than andromeda)
----
d = 1,000,000,000ly (one billion)
I = 1/ 8.9506*10^49 (200,000 times less than andromeda)
---
d = 10,000,000,000ly
I = 1/ 8.9506*10^51 (20 million times less than andromeda)
---
d = ~13,700,000,000ly (farthest observed objects, allegedly)
I = 1/ 1.6799*10^52 (about 100million times less than andromeda)
--------
As stated, given these progressions, identifying the type of object or explosion you are looking at is guesswork. The variables involved are:
relative velocity
relative acceleration
mass of the star
composition of the star
age of the star
distance
space dust
apparant magnitude
QUOTE (->
| QUOTE |
| If that is so, could that be that most of our calculations (I=1/d^2) of distances of light emitting objects be wrong having known that he also stated that the the more far a light emitting celestial object was the faster it moved away? causing our calculations to be even MORE wrong? The way the universe expands is that the distance between galaxies grows, and becomes bigger, they move away from each other, then how is it that the distance between celestial objects inside the galaxies grows(as in stars and planets)? |
Hubble said Red shifted galaxies aren't simply "moving" away from each other, they are actually accelerating away, though the acceleration is very slow.
The relative motion of galaxies clusters that are far enough away as to not be affected significantly by the local group's gravity are moving away from us at velocity found by:
72/km/s/megaparsec.
The distance between celestial objects actually does expand,its just that this expansion is so small you can't observe it because gravity quickly masks it. The expansion between one side of the milkyway and the opposite is almost insignificant. Megaparsec is one million parsecs. Parsec is 3.6 ly. So galaxy "tries" to expand at a rate of 2km/s across its diameter, But the galactic mass is so great that this expansion would be very diffiicult to detect. AT least that would be the interpretation.
So that is hubble's theory.
-----
The big problem I have with using apparant magnitude and luminosities of objects is that its circular reasoning. Identifying a supernova's type from a distant galaxy or from a far edge of our own galaxy is pure guesswork.
I=1/d^2
In any inverse square law, the term "d^2" or "r^2" (for gravity) is measured in meters. this denominator grows ABSURDLY large with astronomical distances.
Here are some examples.
ly = 9.4608*10^15m
Sun
d = 1.5*10^11m
I = 1/ 2.25*10^22
Closest star
d = 3.6 ly
I = 1/1.16*10^33 (100 million times smaller than the sun)
Center of Milkyway
d = ~29,000ly
I = 1/7.5275*10^40 (ten million times less than closest star)
Opposite edge of milky way
d = ~79,000ly
I = 1/ 5.586*10^41
Andromeda Galaxy
d = ~2.1*10^22m
I = 1/4.41*10^44 (ten thousand times less than center of milkyway)
VArious inter- Galactic ranges
d= 10,000,000 ly
I = 1/ 8.9506*10^45 (20 times less than andromeda)
---
d= 100,000,000ly
I = 1/ 8.9506*10^47 (2000 times less than andromeda)
----
d = 1,000,000,000ly (one billion)
I = 1/ 8.9506*10^49 (200,000 times less than andromeda)
---
d = 10,000,000,000ly
I = 1/ 8.9506*10^51 (20 million times less than andromeda)
---
d = ~13,700,000,000ly (farthest observed objects, allegedly)
I = 1/ 1.6799*10^52 (about 100million times less than andromeda)
--------
As stated, given these progressions, identifying the type of object or explosion you are looking at is guesswork. The variables involved are:
relative velocity
relative acceleration
mass of the star
composition of the star
age of the star
distance
space dust
apparant magnitude
It's somewhat funny to me (and I've really only discovered all this information in the last six months) that so many many cosmologists have this seeming blind acceptance of a principle that could have some serious flaws.
I've always said this same thing, but people treat you like a dumbass just for questioning anything that a "scientist" says.
They use an assumption about distance to determine how bright or massive an object is. Then they turn around and use this number to determine how far away another object is. Its circular reasoning based almost entirely on assumptions.
QUOTE
Quantum_Conundrum Posted: Today at 1:19 AM So galaxy "tries" to expand at a rate of 2km/s across its diameter, But the galactic mass is so great that this expansion would be very difficult to detect. AT least that would be the interpretation.
this is nonsense. it is either it expands or it does not expand. if it expands at 2km/s and the milky way is approx 13billion years old, do the math, the milky way would not be its current size.
QUOTE (->
| QUOTE |
| Quantum_Conundrum Posted: Today at 1:19 AM So galaxy "tries" to expand at a rate of 2km/s across its diameter, But the galactic mass is so great that this expansion would be very difficult to detect. AT least that would be the interpretation. |
this is nonsense. it is either it expands or it does not expand. if it expands at 2km/s and the milky way is approx 13billion years old, do the math, the milky way would not be its current size.
They use an assumption about distance to determine how bright or massive an object is
it is not an assumption, it is a simple relation
QUOTE
Then they turn around and use this number to determine how far away another object is. Its circular reasoning based almost entirely on assumptions
no. "they" use different methods eg luminosity and parallax, on nearby stars and if these different methods yield comparable results then "they" have more confidence in saying "star A is too distant for parallax to work, but since parallax and luminosity yield same results on nearby stars, luminosity must work by itself for distant objects"
it seems you have assumed you understand this topic.
QUOTE (kjw+May 31 2008, 04:57 PM)
QUOTE
this is nonsense. it is either it expands or it does not expand. if it expands at 2km/s and the milky way is approx 13billion years old, do the math, the milky way would not be its current size.
the SPACE-TIME in the region expands, but GRAVITY is stronger than 2km/s expansion. Do the math.
Space-time expansion and "objects moving apart" are not necesssarily one and the same if those objects are close enough for gravity to overcome the rate of expansion.
QUOTE (->
| QUOTE |
| this is nonsense. it is either it expands or it does not expand. if it expands at 2km/s and the milky way is approx 13billion years old, do the math, the milky way would not be its current size. |
the SPACE-TIME in the region expands, but GRAVITY is stronger than 2km/s expansion. Do the math.
Space-time expansion and "objects moving apart" are not necesssarily one and the same if those objects are close enough for gravity to overcome the rate of expansion.
no. "they" use different methods eg luminosity and parallax, on nearby stars and if these different methods yield comparable results then "they" have more confidence in saying "star A is too distant for parallax to work, but
it seems you have assumed you understand this topic.
I think we know what parallax is in principle.
its comparing apparant angles to a star at different times of the year and then using geometry to try to calculate the distance.
But the angles are so small that this is just laughable.
closest star
4.04*10^16m
Earth orbital diameter
3*10^11m
QUOTE
since parallax and luminosity yield same results on nearby stars, luminosity must work by itself for distant objects"
But no, it is not proper to make the same assumption about distant objects.
"Nearby stars" aren't really nearby at all.
Do you even know how small the change in angle of an object would really be at 4.04*10^16m distance across a 6 month period?
The change in angle is so small, even for the absolute closest stars in the sky, that the margine of any number of human errors or instrumentation errors completely renders the measurement useless. And this is for the CLOSEST stars.
Its
7.426*10^-6 degrees
You can't even make that measurement because the earth is spinning fast enough that you can't even focus a telescope to within that degree of accuracy fast enough to make a measurement.
I have an auto aligning telescope that cost a couple hundred dollars, and I know that's nothing compared to professional observatories, but the point is, anyone who has actually tried to look at the stars with a telescope knows what I'm talking about. They actually are not easy to keep in the crosshairs even with a computer autocalculating and moving the telescope for you, much less make parallax measurements where the first significant digit is the 6th decimal place.
Compared to the numbers astronomers throw around, 4-5 ly is absolutely nothing.
QUOTE
Quantum_Conundrum Posted on Today at 10:11 AM the SPACE-TIME in the region expands, but GRAVITY is stronger than 2km/s expansion. Do the math. Space-time expansion and "objects moving apart" are not necesssarily one and the same if those objects are close enough for gravity to overcome the rate of expansion.
so what ? you said QUOTE (->
| QUOTE |
| Quantum_Conundrum Posted on Today at 10:11 AM the SPACE-TIME in the region expands, but GRAVITY is stronger than 2km/s expansion. Do the math. Space-time expansion and "objects moving apart" are not necesssarily one and the same if those objects are close enough for gravity to overcome the rate of expansion. |
so what ? you said Quantum_Conundrum Posted on Today at 1:19 AM So galaxy "tries" to expand at a rate of 2km/s across its diameter, But the galactic mass is so great that this expansion would be very diffiicult to detect. AT least that would be the interpretation.
which means the distance (not spacetime) is expanding.
The very best Earth-bound (single) telescopes, working patiently over decades, are able to measure accurately shifts of about 0.003 arcseconds.
http://spiff.rit.edu/classes/phys240/lectu...x/parallax.html
7.426*10^-6 degrees = approx 0.027arcseconds, well within earth bound limitations
that is plenty big enough
The very best Earth-bound (single) telescopes, working patiently over decades, are able to measure accurately shifts of about 0.003 arcseconds.
http://spiff.rit.edu/classes/phys240/lectu...x/parallax.html
7.426*10^-6 degrees = approx 0.027arcseconds, well within earth bound limitations
yes you can see above
measuring hundredths or thousands of an arcsecond is impossible, regardless of what your reference says.
Anything as simple as the vibrations of someone walking or a piece of dust in the telescope's gears, or even humidity or air temperature, would throw these measurements off.
This is why I am so skeptical of these sorts of claims, because the accuracy and precision they are claiming to have simply does not exist.
that all depends on how you measure it. astronomers make use platescale in parallax determinations. the camera, NSFCAM2, used in at the NASA Infrared Telescope Facility in hawaii has a platescale of 0.039706arcsec/pixel
that all depends on how you measure it. astronomers make use platescale in parallax determinations. the camera, NSFCAM2, used in at the NASA Infrared Telescope Facility in hawaii has a platescale of 0.039706arcsec/pixel
Anything as simple as the vibrations of someone walking or a piece of dust in the telescope's gears, or even humidity or air temperature, would throw these measurements off.
yes. that is why you have calibrations, operating procedures, operating specifications etc.
not used a scientific instrument befor eh?
well there you have it, no need to be skeptical anymore. the accuracy and precision to 0.039706arcsec exists.
The measurements in our own galaxy are highly questionable. 0.02673... arc seconds +/- 0.003 arc seconds is a very, very big degree of error when you are talking about "light years", and I still don't believe those numbers anyway.
0.02373 - 0.02973 arc seconds. Lets see, what is the range of error for the calculation for nearest star?
4.551*10^16 - 3.633*10^16
Basicly that's a margin of error in the distance calculation of +/- 10% for the closest possible inter-stellar distance measurement, and that's given the absurd degree of accuracy that the astronomers claim to have.
So how can you take these numbers seriously?
I do not believe the claims that an astronomer could use a telescope to measure angles to within +/-0.003 arc seconds, because that level of accuracy would require the telescope to be constructed and aligned to within one millionth of a micron of specifications.
That doesn't even consider the other variables: geologic change of the earth, errors in our calendar, and as stated temperature, dust, humidity, rust, etc.
The measurements in our own galaxy are highly questionable. 0.02673... arc seconds +/- 0.003 arc seconds is a very, very big degree of error when you are talking about "light years", and I still don't believe those numbers anyway.
0.02373 - 0.02973 arc seconds. Lets see, what is the range of error for the calculation for nearest star?
4.551*10^16 - 3.633*10^16
Basicly that's a margin of error in the distance calculation of +/- 10% for the closest possible inter-stellar distance measurement, and that's given the absurd degree of accuracy that the astronomers claim to have.
So how can you take these numbers seriously?
I do not believe the claims that an astronomer could use a telescope to measure angles to within +/-0.003 arc seconds, because that level of accuracy would require the telescope to be constructed and aligned to within one millionth of a micron of specifications.
That doesn't even consider the other variables: geologic change of the earth, errors in our calendar, and as stated temperature, dust, humidity, rust, etc.
I'm going to assuem that you're not lying, and simply ignorant of this article, released in Feb 2008 (and featured on Physorg) http://www.aanda.org/index.php?option=arti...4-6361:20078961 where Astronomers at la silla in Peru measured the distance to RS Pup, a cepheid variable in our own galaxy, to an accuracy of 1% (here http://www.eso.org/public/outreach/press-r...8/pr-05-08.html is the ESO news release).
Or of this 2000 paper where the distance to Cepheid variables in a cluster in the LMC was measured to an accuracy of 4%.
The la silla observatory itself is built on a 2,400m high mountain in the Atacama Desert in Peru.
The average humidity at the la silla observatory is 5-10%, and it receives <1cm of rain/year (<0.5 inch).
So your objections of dust and humidity are bunk.
The telescope itself has a 3.6m (141 inch) primary mirror that uses active optics in a real time setup to maintain optimal shape.
I'm not sure what the optical resolution of the NTT is, beyond that it has a plate scale of 5.35 arc seconds per mm (no idea how many pixels per mm).
So again, your objections are bunk, and appear to be based in ignorance more then anything else.
The plate scale was measured to be 0.039706 ± 0.000017
PS i was going to use the HIPPARCOS for the benefit of Quantum_Conundrum, but soon realized that this would be too much to comprehend...
QUOTE
Quantum_Conundrum Posted on Today at 10:11 AM Its 7.426*10^-6 degrees
that is plenty big enoughThe very best Earth-bound (single) telescopes, working patiently over decades, are able to measure accurately shifts of about 0.003 arcseconds.
http://spiff.rit.edu/classes/phys240/lectu...x/parallax.html
7.426*10^-6 degrees = approx 0.027arcseconds, well within earth bound limitations
QUOTE (->
| QUOTE |
| Quantum_Conundrum Posted on Today at 10:11 AM Its 7.426*10^-6 degrees |
that is plenty big enough
The very best Earth-bound (single) telescopes, working patiently over decades, are able to measure accurately shifts of about 0.003 arcseconds.
http://spiff.rit.edu/classes/phys240/lectu...x/parallax.html
7.426*10^-6 degrees = approx 0.027arcseconds, well within earth bound limitations
You can't even make that measurement
The very best Earth-bound (single) telescopes, working patiently over decades, are able to measure accurately shifts of about 0.003 arcseconds.
http://spiff.rit.edu/classes/phys240/lectu...x/parallax.html
7.426*10^-6 degrees = approx 0.027arcseconds, well within earth bound limitations
You can't even make that measurement
yes you can see above
QUOTE
because the earth is spinning fast enough that you can't even focus a telescope to within that degree of accuracy fast enough to make a measurement.
QUOTE (kjw+May 31 2008, 08:16 PM)
that is plenty big enough
The very best Earth-bound (single) telescopes, working patiently over decades, are able to measure accurately shifts of about 0.003 arcseconds.
http://spiff.rit.edu/classes/phys240/lectu...x/parallax.html
7.426*10^-6 degrees = approx 0.027arcseconds, well within earth bound limitations
yes you can see above
measuring hundredths or thousands of an arcsecond is impossible, regardless of what your reference says.
Anything as simple as the vibrations of someone walking or a piece of dust in the telescope's gears, or even humidity or air temperature, would throw these measurements off.
This is why I am so skeptical of these sorts of claims, because the accuracy and precision they are claiming to have simply does not exist.
QUOTE
Quantum_Conundrum Posted: Today at 11:49 AM measuring hundredths or thousands of an arcsecond is impossible, regardless of what your reference says.
that all depends on how you measure it. astronomers make use platescale in parallax determinations. the camera, NSFCAM2, used in at the NASA Infrared Telescope Facility in hawaii has a platescale of 0.039706arcsec/pixel
QUOTE (->
| QUOTE |
| Quantum_Conundrum Posted: Today at 11:49 AM measuring hundredths or thousands of an arcsecond is impossible, regardless of what your reference says. |
that all depends on how you measure it. astronomers make use platescale in parallax determinations. the camera, NSFCAM2, used in at the NASA Infrared Telescope Facility in hawaii has a platescale of 0.039706arcsec/pixel
Anything as simple as the vibrations of someone walking or a piece of dust in the telescope's gears, or even humidity or air temperature, would throw these measurements off.
yes. that is why you have calibrations, operating procedures, operating specifications etc.
not used a scientific instrument befor eh?
QUOTE
This is why I am so skeptical of these sorts of claims, because the accuracy and precision they are claiming to have simply does not exist.
well there you have it, no need to be skeptical anymore. the accuracy and precision to 0.039706arcsec exists.
QUOTE (uaafanblog+Mar 28 2008, 03:48 PM)
One of the major questioners of this whole Cephied/Standard Candle measurement process is a guy called Geoffrey Burbridge who points out that there is an existing "noncosmological redshift" that isn't taken into account (i.e... they're "redder" to begin with). Additionally, there are probabilities that absorption by the intergalactic medium (whatever it is) could have a major effect.
Irrelevant.
Reddening by the insterstellar medium (in this case, I refer to the background of Hydrogen, Helium, dust, etc - the standard definition of the ISM) does not affect the redshift observed in interstellar spectra.
More to the point, the Cephied variable standard candle is not reliant on redshift, it uses the correlation between the brightness of the star, and the period of the oscillations.
A correlation that has been verified to a very high degree of accuracy by experimental observations made of Cephied variables in our own galaxy.
Irrelevant.
Reddening by the insterstellar medium (in this case, I refer to the background of Hydrogen, Helium, dust, etc - the standard definition of the ISM) does not affect the redshift observed in interstellar spectra.
More to the point, the Cephied variable standard candle is not reliant on redshift, it uses the correlation between the brightness of the star, and the period of the oscillations.
A correlation that has been verified to a very high degree of accuracy by experimental observations made of Cephied variables in our own galaxy.
QUOTE
A correlation that has been verified to a very high degree of accuracy by experimental observations made of Cephied variables in our own galaxy.
The measurements in our own galaxy are highly questionable. 0.02673... arc seconds +/- 0.003 arc seconds is a very, very big degree of error when you are talking about "light years", and I still don't believe those numbers anyway.
0.02373 - 0.02973 arc seconds. Lets see, what is the range of error for the calculation for nearest star?
4.551*10^16 - 3.633*10^16
Basicly that's a margin of error in the distance calculation of +/- 10% for the closest possible inter-stellar distance measurement, and that's given the absurd degree of accuracy that the astronomers claim to have.
So how can you take these numbers seriously?
I do not believe the claims that an astronomer could use a telescope to measure angles to within +/-0.003 arc seconds, because that level of accuracy would require the telescope to be constructed and aligned to within one millionth of a micron of specifications.
That doesn't even consider the other variables: geologic change of the earth, errors in our calendar, and as stated temperature, dust, humidity, rust, etc.
QUOTE (Quantum_Conundrum+Jun 2 2008, 05:31 AM)
The measurements in our own galaxy are highly questionable. 0.02673... arc seconds +/- 0.003 arc seconds is a very, very big degree of error when you are talking about "light years", and I still don't believe those numbers anyway.
0.02373 - 0.02973 arc seconds. Lets see, what is the range of error for the calculation for nearest star?
4.551*10^16 - 3.633*10^16
Basicly that's a margin of error in the distance calculation of +/- 10% for the closest possible inter-stellar distance measurement, and that's given the absurd degree of accuracy that the astronomers claim to have.
So how can you take these numbers seriously?
I do not believe the claims that an astronomer could use a telescope to measure angles to within +/-0.003 arc seconds, because that level of accuracy would require the telescope to be constructed and aligned to within one millionth of a micron of specifications.
That doesn't even consider the other variables: geologic change of the earth, errors in our calendar, and as stated temperature, dust, humidity, rust, etc.
I'm going to assuem that you're not lying, and simply ignorant of this article, released in Feb 2008 (and featured on Physorg) http://www.aanda.org/index.php?option=arti...4-6361:20078961 where Astronomers at la silla in Peru measured the distance to RS Pup, a cepheid variable in our own galaxy, to an accuracy of 1% (here http://www.eso.org/public/outreach/press-r...8/pr-05-08.html is the ESO news release).
Or of this 2000 paper where the distance to Cepheid variables in a cluster in the LMC was measured to an accuracy of 4%.
The la silla observatory itself is built on a 2,400m high mountain in the Atacama Desert in Peru.
The average humidity at the la silla observatory is 5-10%, and it receives <1cm of rain/year (<0.5 inch).
So your objections of dust and humidity are bunk.
The telescope itself has a 3.6m (141 inch) primary mirror that uses active optics in a real time setup to maintain optimal shape.
I'm not sure what the optical resolution of the NTT is, beyond that it has a plate scale of 5.35 arc seconds per mm (no idea how many pixels per mm).
So again, your objections are bunk, and appear to be based in ignorance more then anything else.
QUOTE
Quantum_Conundrum Posted on Today at 3:31 AM I do not believe the claims that an astronomer could use a telescope to measure angles to within +/-0.003 arc seconds, because that level of accuracy would require the telescope to be constructed and aligned to within one millionth of a micron of specifications.
you dont even want to be educated. i gave you a link to a working telescope that does measure these values. if you read the link you would of seenThe plate scale was measured to be 0.039706 ± 0.000017
QUOTE (kjw+Jun 2 2008, 09:37 AM)
you dont even want to be educated. i gave you a link to a working telescope that does measure these values. if you read the link you would of seen
The plate scale was measured to be 0.039706 ± 0.000017
I think the VLT gets something like 0.0005, or something equally ridiculous.
HIPPARCOS catalogued 120,000 stars to miliarcsecond accuracy.
The plate scale was measured to be 0.039706 ± 0.000017
I think the VLT gets something like 0.0005, or something equally ridiculous.
HIPPARCOS catalogued 120,000 stars to miliarcsecond accuracy.
QUOTE
Trippy Posted on Today at 7:49 AM I think the VLT gets something like 0.0005, or something equally ridiculous.
HIPPARCOS catalogued 120,000 stars to miliarcsecond accuracy.
i literally get goosebumps just thinking about those instrumentsHIPPARCOS catalogued 120,000 stars to miliarcsecond accuracy.
PS i was going to use the HIPPARCOS for the benefit of Quantum_Conundrum, but soon realized that this would be too much to comprehend...
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