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individual stars can be gravitational lenses (micro lenses)

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posted on Oct, 30 2012 @ 02:48 PM
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there has been a debate raging on these boards between me and some members,

my stance has always been that individual stars can be considered as "gravitational lenses" and some high profile members have accused me of "you believe that everything is a gravity lens" (no names)

well it looks like stars CAN be lenses, micro lenses have been studied in and around our galaxy and have been found to be "micro lenses" that "distort" the images of stars behind them or "in their vicinity"


Astronomers' model sheds light on microlensing event



In order for MACHOs to make up dark matter, they must be so faint that they can't be directly detected. Instead, astronomers looked for a phenomenon known as microlensing. During a microlensing event, a nearby object passes in front of a more distant star. The gravity of the closer object bends light from the star like a lens, magnifying it and causing it to brighten.

Read more at: phys.org...


phys.org...

this "star scale lensing" is added to the individual "galaxy optical gravitational lensing"
and "galaxy cluster lensing" and "filament gravitational lensing"

it would seem that the lists of objects that can be considered "gravitational lenses" has expanded from,

super massive clusters of galaxies with "combined masses" great enough to warp space time into a lens,
then individual galaxies with "a much smaller combined mass" great enough to lense objects in the back round,
to individual stars "with a very small fraction of the mass of individual galaxies" (micro lense)

so the evidence is starting to add up that alot of what we observe in the universe has the ability to distort or "collect and magnify" light of objects in the immediate background.

recent observations of "filamentary material acting as gravitational lenses"


when Einstein first theorized "gravitational lensing" it was considered that only large "clusters" of galaxies would be large enough to warp space time into a lense to collect and amplify light,



an example of an Einstein ring,


then in 2010 a discovery of "a signature of lensing" was theorized and discovered to be sub mm and Infra Red light,



when these objects were viewed in "optical" wavelengths" it was realised that these objects were "gravitational lenses" but they were "individual galaxies" which was quite stunning.



so the new theory was that these individual galaxy lenses were part gravitational lenses augmented by simple optical lensing to provide "lensing potential"



how the backround is distorted by individual galaxies


a little science,


now we have some evidence that individual "stars" can be used as "micro lenses" and in fact distort the background objects.




By studying the LMC, astronomers hoped to see MACHOs within the Milky Way lensing distant LMC stars. The number of microlensing events observed by various teams was smaller than needed to account for dark matter, but much higher than expected from the known population of stars in the Milky Way. This left the origin of the observed events a puzzle and the existence of MACHOs as exotic objects a possibility. "We originally set out to understand the evolution of the interacting LMC and SMC galaxies," explains lead author Gurtina Besla of Columbia University. "We were surprised that, in addition, we could rule out the idea that dark matter is contained in MACHOs." "Instead of MACHOs, a trail of stars removed from the SMC is responsible for the microlensing events," says co-author Avi Loeb of the Harvard-Smithsonian Center for Astrophysics.

Read more at: phys.org...


www.abovetopsecret.com...

if we add all of these different mechanisms together,
we find that individual galaxies, can be macro lenses, and the stars "within the host" can be micro lenses,
which gives us a "compound" lens of extra ordinary strength.

this causes a very complicated "light signature" that can "signal" the combination of macro and micro lensing of stars "within" an individual galaxy



so what about the "cosmic microwave backround" is it to an artifact of all the lensing going on?

from a NASA release from 2010


it is looking more and more like nearly every thing can be considered a lens,
and now that includes stars.



after all even the shape of these objects are conducive to lensing

the inner portion of an eliptical galaxy "side on" even looks like a magnifying glass,


and the outter "dark matter halo" would act like another lens,


which creates a whole "mess" of lenses "compounding" their effects on each other



the universe just keeps getting more interesting



xploder
edit on 30-10-2012 by XPLodER because: add cluster lensing pic




posted on Oct, 30 2012 @ 03:22 PM
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reply to post by XPLodER
 


L
L
seems obvious to me
focal length would be proportional to gravity and size of gravitational source.



posted on Oct, 30 2012 @ 03:26 PM
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reply to post by XPLodER
 


I thought stars being used as gravitational lenses was well documented?

Maybe I'm missing something but I try and keep up on the science headlines. When I saw your title I went, "Well, duh of course they are!"

What are these other members claiming?
edit on 30-10-2012 by MystikMushroom because: (no reason given)



posted on Oct, 30 2012 @ 04:53 PM
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Originally posted by MystikMushroom
reply to post by XPLodER
 


I thought stars being used as gravitational lenses was well documented?

Maybe I'm missing something but I try and keep up on the science headlines. When I saw your title I went, "Well, duh of course they are!"

What are these other members claiming?
edit on 30-10-2012 by MystikMushroom because: (no reason given)


i was accused of believing that everything we can see outside of our galaxy,
was a gravitational lens,

and that i was grav lens "happy"

so i decided to document the different types of lenses to show that i was not alone in my conclusions.

this physorg article shows that MACHOs are unlikly to be the cause of the micro lensing we can see from the LMC (Large Magellanic Cloud) distorting the SMC (small Magellanic Cloud) light,

and that individual stars as "micro lenses" are a better fit.

this conclusively adds stars to the growing list of objects capable of "lensing light from exterior origins"

i thought if i put it as simply as possible other members would be able to join in and enjoy



xploder



posted on Oct, 30 2012 @ 05:01 PM
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Originally posted by DerepentLEstranger
reply to post by XPLodER
 


L
L
seems obvious to me
focal length would be proportional to gravity and size of gravitational source.


its starting to look like there is an optical component to conciser in these equations as well,

take a look at individual galaxy lensing for example

xploder



posted on Oct, 30 2012 @ 05:05 PM
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reply to post by XPLodER
 


i was accused of believing that everything we can see outside of our galaxy,
was a gravitational lens,


I think the criticism had more to do with your ideas about the heliosphere having a lensing effect and how that effect makes the whole universe appear smaller than it really is. Sort of like "objects in the lens are farther than they appear".

Gravitational lensing isn't quite that.



posted on Oct, 30 2012 @ 05:40 PM
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Originally posted by Phage
reply to post by XPLodER
 


i was accused of believing that everything we can see outside of our galaxy,
was a gravitational lens,


I think the criticism had more to do with your ideas about the heliosphere having a lensing effect and how that effect makes the whole universe appear smaller than it really is. Sort of like "objects in the lens are farther than they appear".

Gravitational lensing isn't quite that.


hello phage


thank you for the clarification,

it is commonly accepted that without gravitational lensing very distant objects would not be "visible' to us and our telescopes, this is predicated on the ability of large masses to collect and focus light from distant sources and "increase" our ability to "see further" and detect them.

on the other hand we know that lenses (differing refractive densities) can act to collect and focus light as well,
"telescopes" are an optical example of this,

so if the same shapes and refractive density changes can used as a telescope,
why could we discount the ability of "optical" lenses to act in a similar manner?

an example would be binoculars, using known optical physics we can use the shape and refractive index difference in air and lensing materials to make objects appair "closer" to the observer,

using the same rules, what would stop these same factors from amking this look further away

example,
look backwards through the same pair of binoculars and object "appair" more distant?

add to that the gravitational potential of a single sun and its abiltiy to "bend light" on its path and you have a situation not unlike looking through binoculars "backwards"

what do you think?

xploder



posted on Oct, 30 2012 @ 05:56 PM
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reply to post by XPLodER
 


it is commonly accepted that without gravitational lensing very distant objects would not be "visible' to us and our telescopes, this is predicated on the ability of large masses to collect and focus light from distant sources and "increase" our ability to "see further" and detect them.
Yes, gravitational lensing collects light. This does not make distant objects appear closer, that is not what the distance calculations are based upon.


an example would be binoculars, using known optical physics we can use the shape and refractive index difference in air and lensing materials to make objects appair "closer" to the observer,
Binoculars use very precise alignment and spacing of prisms and lenses to enlarge distant objects. When I use binoculars I do not normally use the view to determine the distance of the objects I am looking at, I use it to make to objects more readily visible. However, knowing the characteristics of the optical system and the actual size of an object I could do so.


add to that the gravitational potential of a single sun and its abiltiy to "bend light" on its path and you have a situation not unlike looking through binoculars "backwards"

what do you think?
I think you are oversimplifying. The distance of very distant objects is not determined simply by how they appear as a result of gravitational lensing.
edit on 10/30/2012 by Phage because: (no reason given)



posted on Oct, 30 2012 @ 06:57 PM
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reply to post by XPLodER
 


well wasn't one of the proofs of relativity the deflection of starlight by the sun?
in addition to proportionality i also meant it would be a function of

perhaps instead of saying individual stars can be gravitational lenses (micro lenses)
it would be more correct/specific to say that it's gravity wells that act as lenses?



posted on Oct, 30 2012 @ 07:23 PM
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Originally posted by DerepentLEstranger
reply to post by XPLodER
 


well wasn't one of the proofs of relativity the deflection of starlight by the sun?
in addition to proportionality i also meant it would be a function of


well i have read that observations after Einstein have shown a different story,


while the solar plasma does look to have an effect, the squared distance law does not seem to correlate with actual observations


perhaps instead of saying individual stars can be gravitational lenses (micro lenses)
it would be more correct/specific to say that it's gravity wells that act as lenses?




while i agree about the terminology you use, IMHO it is the shape and reflective properties of the helo sphere that produces "lensing" and is "mainly" an artifact of the outter circumference of the "bubble" of the helio sphere,

not withstanding the "small" amount of plasma "lensing" from the suns corona

when the "outter" edge of the bubble moves to obscure a back ground source,
THAT is when the highest deflections are recorded in micro lensing,

this leads me to conclude, that it is optical in nature

xploder



posted on Oct, 30 2012 @ 07:46 PM
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Originally posted by Phage
reply to post by XPLodER
 


it is commonly accepted that without gravitational lensing very distant objects would not be "visible' to us and our telescopes, this is predicated on the ability of large masses to collect and focus light from distant sources and "increase" our ability to "see further" and detect them.
Yes, gravitational lensing collects light. This does not make distant objects appear closer, that is not what the distance calculations are based upon.


an example would be binoculars, using known optical physics we can use the shape and refractive index difference in air and lensing materials to make objects appair "closer" to the observer,
Binoculars use very precise alignment and spacing of prisms and lenses to enlarge distant objects. When I use binoculars I do not normally use the view to determine the distance of the objects I am looking at, I use it to make to objects more readily visible. However, knowing the characteristics of the optical system and the actual size of an object I could do so.


add to that the gravitational potential of a single sun and its abiltiy to "bend light" on its path and you have a situation not unlike looking through binoculars "backwards"

what do you think?
I think you are oversimplifying. The distance of very distant objects is not determined simply by how they appear as a result of gravitational lensing.
edit on 10/30/2012 by Phage because: (no reason given)


well.....

if on a small scale a nano sized spherical lens can increase magnification,

picture of a nano scale "spherical glass bead" on top of a substence being magnified by a microscope


and this is simply due to the size, shape, and refractive index of the nano scale glass bead,
why couldn't a larger scale spherical object (heliosphere) with a difference in surrounding refractive material,
also have an "effect" on perceived size?

IMHO
if we were "inside the nano scale glass bead" under a micro scope (as in pic)
we would have a distorted "perceived" view of objects outside of the glass bead (heliosphere)

they would "appair" to our observation to be smaller and further away.
"objects in the mirror are CLOSER than they appair

what do you think?

xploder



posted on Oct, 30 2012 @ 07:50 PM
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reply to post by XPLodER
 


they would "appair" to our observation to be smaller and further away.
"objects in the mirror are CLOSER than they appair

what do you think?

The apparent size of astronomical objects is not used to determine their distance.



posted on Oct, 30 2012 @ 07:57 PM
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Originally posted by Phage
reply to post by XPLodER
 


they would "appair" to our observation to be smaller and further away.
"objects in the mirror are CLOSER than they appair

what do you think?

The apparent size of astronomical objects is not used to determine their distance.


i realise the standard candle argument,
type 1A super nova are "expected" to be effected in a similar "manner" as the matter is transformed into light,



but in an alternate explanation of the dynamics involved, the magnitude is expected to be effected by the fact that mass is "moving outward" from a central point (point source) to a distributed mass situation.



the energy released is expected to behave in an manner that follows the curve as above.

point being,
how can we use type 1A as a reliable source of distance when the dynamics of gravity and mass distribution is variable "as the system changes from mass centered to mass distrabution?

xploder



posted on Oct, 30 2012 @ 08:03 PM
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reply to post by XPLodER
 

Brightness is not used to calculate the distance of very distant objects.

Correction. Not the only method.
edit on 10/30/2012 by Phage because: (no reason given)



posted on Oct, 30 2012 @ 08:29 PM
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Originally posted by Phage
reply to post by XPLodER
 

Brightness is not used to calculate the distance of very distant objects.


err opps


Thus, we can observe a Cepheid, note how long it takes for its brightness to vary and plot that information on an already established graph to find out its intrinsic luminosity. Comparing this true brightness (its 'absolute magnitude') with its apparent brightness as seen in the sky (its 'apparent magnitude') allows us to calculate how far away it is, using the inverse-square law of brightness. "Fortunately, Cepheids are luminous enough that they can be observed in other galaxies, not just in our own. In the 1920s Edwin Hubble used the period-luminosity relation for variable stars to establish the distances to various galaxies and proved that they lie far outside our Milky Way.


www.scientificamerican.com...

my bad, i thought we used type 1A as a distance indicator lol

ok so the crux of where we differ in opinion,

i believe that optical and gravitational considerations would "affect" the apparent magnitude and absolute magnitude results,

and in that case how could you plot the HR diagram?

just questions
dont get mad at me


xploder



posted on Oct, 30 2012 @ 08:31 PM
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reply to post by XPLodER
 


i believe that optical and gravitational considerations would "affect" the apparent magnitude and absolute magnitude results
What makes you thing that would not be considered in the calculations?

And are you ignoring redshift?



posted on Oct, 30 2012 @ 08:56 PM
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Originally posted by Phage
reply to post by XPLodER
 


i believe that optical and gravitational considerations would "affect" the apparent magnitude and absolute magnitude results
What makes you thing that would not be considered in the calculations?

And are you ignoring redshift?


not successfully, so far, lol
but i am interested in using AGN as standard candles,


A NEW COSMOLOGICAL DISTANCE MEASURE USING AGN



One of the simplest and, perversely, most intractable problems in astronomy has been to discover how far away something is. New distance measures have led to fundamental
changes in our understanding of the Universe; for example
Tycho Brahe’s supernova and Edwin Hubble’s Cepheids radically reshaped our understanding of the cosmos. It is almost
two decades since type Ia supernovae (SNe) were shown to
be accurate standard candles (Phillips 1993). That distance
measure led directly to the discovery of the acceleration of
the Universe and dark energy


link to PDF

i dont discount the "standard candle argument" (lack of evidence to say other wise)
or
the red shift = distance (again i have no evidence to say otherwise)

but both of these observations rely on light, optics and distance,
which are the basic elements of telescopes, and leads me to explore "alternative explanations"
mainly optics



xploder






edit on 30-10-2012 by XPLodER because: (no reason given)



posted on Oct, 31 2012 @ 12:25 AM
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It does sound like an interesting project trying to quantify the lensing effect of the heliosphere. Considering how much trouble man had in first hitting the moon, trying to hit a star is in a new order of complexity. If we had a decent telescope on voyager it would give a good frame of reference conclusively to prove how much effect there is, without it we need other methods.

All of the night sky passes through this heliosphere filter, so it is all subject to the same distortions, be that 0 effect, very minor or quite considerable. So trying to define this effect through referencing star relationships has its problems as it is all subject to the same unknown error.

So if we just focus on just one star and go back to your glass sphere analogy, as we move around in side the glass sphere, the distortions to our perception of the outside will change. I am not sure if our telescopes are sensitive enough to measure any such distortions, but when we are closest to the star in our annual orbit any distortions will be at their minimum and more circular in shape. At the points of 3 months before and 3 months after, any distortions will be at our practically measurable maximum with a slight oval shape. Depending how much change there is between these circular and oval shapes over the year will help define how much influence the heliosphere has in our perception of the universe.



posted on Oct, 31 2012 @ 11:50 AM
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Xploder, if these lenses are causing a distortion, then presumably the 'lens' of our own solar system, or at least our own galaxy, is impacting every other galaxy we look at. Theoretically if this lens was expanding outwards, which is reasonably likely, then do you think this would cause everything outside our galaxy to appear to be moving away? Or do you think this is not possible.

If that was happening, that would change physics in a big way! Am I getting the wrong idea here?



posted on Oct, 31 2012 @ 03:34 PM
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hi



Originally posted by kwakakev
It does sound like an interesting project trying to quantify the lensing effect of the heliosphere. Considering how much trouble man had in first hitting the moon, trying to hit a star is in a new order of complexity. If we had a decent telescope on voyager it would give a good frame of reference conclusively to prove how much effect there is, without it we need other methods.


i agree, a decent telescope on voyager would very quickly resolve this question of optical distortion in the helio sphere.


All of the night sky passes through this heliosphere filter, so it is all subject to the same distortions, be that 0 effect, very minor or quite considerable. So trying to define this effect through referencing star relationships has its problems as it is all subject to the same unknown error.


and the problem of unknown distance between reference stars, i guess parallax to stars would have to be considered "affected" by the distortion, are there any "oddities" you know of due to stellar parallax?


So if we just focus on just one star and go back to your glass sphere analogy, as we move around in side the glass sphere, the distortions to our perception of the outside will change. I am not sure if our telescopes are sensitive enough to measure any such distortions, but when we are closest to the star in our annual orbit any distortions will be at their minimum and more circular in shape. At the points of 3 months before and 3 months after, any distortions will be at our practically measurable maximum with a slight oval shape. Depending how much change there is between these circular and oval shapes over the year will help define how much influence the heliosphere has in our perception of the universe.


i like it,
your right, as the angle of incidence to the curvature changes, so to would the shape, question is do we pick a star on the earth axis or the sun axis? or would it be better to pick one we "think" is close?

xploder






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