individual stars can be gravitational lenses (micro lenses)

Originally posted by theDarthvader
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.

yes you are correct, if we were at the centre of an gravity/optically lensing galaxy,
and that galaxy was expanding, in theory it would give "apparent motion" to objects out side galaxy, from the perspective of an observer inside,

the exact same thing would be true for a galaxy that was contracting
except the "apparent motion" would be in the other direction

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

there is no evidence of this yet, so dont rewrite physics just yet
but if we could measure these distortions, we could "account" for them and adjust our distance calculations to our Stella neighbours,

that is why we keep referencing
"objects in the mirror are closer than they appair"

i think our distance perspective is "false" but unless a measurement of the distortion and its optical implications can be made it would be very difficult to proove,

i like the idea of attempting to measure it as suggested above
observations over maths

xploder

reply to post by XPLodER

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?

I would consider it more limitations than oddities from stellar parallax. Stellar parallax does define the relationships of closeness with our nearby stars, but still leaves the door open on the actual distance as further accounting maybe required, with heliosphere distortions as one example with the lights long journey.

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?

Picking on stars on the suns axis will provide the most circular in shape as there is less curvature or refraction through our solar system medium. Picking on stars that are closer will reduce the possibility of other deep space distortions to enter the calculations. Picking on stars that are brighter will provide better resolution and clarity for identifying any small distortions.

Just to clarify the part on the solar axis. The biggest distortions will be found along the plane where the Earth moves the most over the year, the more you move inside the glass sphere the more distortions you see. So at the North and South poles of the Sun it will be harder to detect any distortions over the year. Basically we need to look along the the sky line that the sun and planets travel to have the best chance.

YES.
Awesome stuff. I wont nitpick all the details of your science, cause most of it is some of the coolest stuff in astrophysics today!

While an undergrad this paper came out.
arxiv.org...
It crushed my dreams because I had heard about using the Suns ability to magnify the hydrogen line at 1420 MHz the coined term "waterhole" frequency* for interstellar communications, as well as as a "super magnifier".

And, then I hadn't given it much thought. But I did some googleing just now and I found this...
www.snolab.ca...
OMG OMG OMG OMG OMG lol

*seti coined term I believe.

Thinking about these distortions a bit more, while there will not be as much distortion over the year at the north and south poles (Northern Star and Southern Cross regions), what distortion effect is applied will rotate throughout the year. So the stars along the suns equator will change from circular to oval shape, while the stars at the suns poles will have their oval shape rotate.

Another way to help get things adding up is to calculate the variations in the refractive index on either side of the heliosphere. Density is one factor in refraction and Voyager has proven there is a difference in density as we pass the heliosphere. While the variation in refraction will be very small, considering how many million of miles is involved it will make some difference.

Originally posted by kwakakev
Thinking about these distortions a bit more, while there will not be as much distortion over the year at the north and south poles (Northern Star and Southern Cross regions), what distortion effect is applied will rotate throughout the year. So the stars along the suns equator will change from circular to oval shape, while the stars at the suns poles will have their oval shape rotate.

Another way to help get things adding up is to calculate the variations in the refractive index on either side of the heliosphere. Density is one factor in refraction and Voyager has proven there is a difference in density as we pass the heliosphere. While the variation in refraction will be very small, considering how many million of miles is involved it will make some difference.

i have been trying to think through weather or not a longer base line would provide more change in shape,
or if multiple observation angles could be used, and the difference between the total amount of deflection could be used to calculate a refractive value,

?????

i also agree on your point with the location and angle of candidates,
the voyager "density difference" could be an indicator of refractive index changes,

the more i consider this the more i think you have a possable way to measure the deflection

xploder

Originally posted by ubeenhad
YES.
Awesome stuff. I wont nitpick all the details of your science, cause most of it is some of the coolest stuff in astrophysics today!

While an undergrad this paper came out.
arxiv.org...
It crushed my dreams because I had heard about using the Suns ability to magnify the hydrogen line at 1420 MHz the coined term "waterhole" frequency* for interstellar communications, as well as as a "super magnifier".

And, then I hadn't given it much thought. But I did some googleing just now and I found this...
www.snolab.ca...
OMG OMG OMG OMG OMG lol

*seti coined term I believe.

edit on 2-11-2012 by ubeenhad because: (no reason given)

it is an interesting idea, but would use the lensing potential of our own sun could be enhanced by the "smaller" deflection available from using planets as a secondary "lensing element"
this may even reduce the total distance required to provide the effect,

thanks for linking

xploder

reply to post by XPLodER

i have been trying to think through weather or not a longer base line would provide more change in shape,

A longer base line will provide more change in shape if there is a deflection taking place. So if we are looking straight through the exact center of the sphere there is no deflection so the baseline does not matter, if we are off center then deflection is taking place and the baseline will factor into it.

if multiple observation angles could be used, and the difference between the total amount of deflection could be used to calculate a refractive value,

Yes, multiple observations must be used to find any distortions over the annual cycle. Considering how telescopes are sensitive enough to detect the wobble in nearby stars to search for planets, there is going to be a bit of work involved in trying to isolate any other distortions, but looking for a change from circular to oval shape is where I would start. If our heliosphere causes light to bend, then so would the stars own heliosphere as well. There may also be other galactic forces at play with black holes a common one, the center of the galaxy may also contribute some bending of the light with its galactic gravitational influence and it does appear that the interstellar medium is more dense than the intergalactic medium which will introduce other distortions for further away object.

If a refractive measurement of a stars distortion can be matched with a calculation of the refractive index of the heliosphere then it is strong, quantifiable evidence of the effect the heliosphere has on light. At the moment I would expect to see a close match, but there will still be some minor disparity as the lights full journey needs accounting.

Originally posted by theDarthvader
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?

here is what we are looking at, when looking at galaxy scale "halos" and "lenses"

The left image, taken by the Hubble Space Telescope, shows a ring of light from a distant galaxy surrounding a closer or foreground galaxy (galaxy SDSS J1631 + 1854), which is at the center of the left image. The closer galaxy is called a “gravitational lens” because its gravity bends light from the more distant galaxy to form the ring of light, named an Einstein ring, as seen from the telescope. The image on the right has been adjusted to remove the lens galaxy and show the ring more clearly. In a new study, University of Utah astronomer Adam Bolton and colleagues measured these Einstein rings to determine the mass of 79 lens galaxies that are massive elliptical galaxies, the largest kind of galaxy with 100 billion stars. The study found the centers of these big galaxies are getting denser over time, evidence of repeated collisions between massive galaxies. Credit: Joel Brownstein, University of Utah, for NASA/ESA and the Sloan Digital Sky Survey

Read more at: phys.org...

phys.org...

there is a difference in apparent motion depending on a few factors,
1/ the galactic "halo" around the galaxy
2/ the "lensing galaxy" at its centre
3/ the surrounding density and refractivity
4/ the angle we encounter the lens at "incidence angle"

so from the example if we were "inside" the galaxy portion of the diagram (coloured centre region)
and the lens portion inflated in area, while the "halo" portion stayed the same overall volume,
there would be some interesting "optical effects" (optical illusions)
including apparent velocity,

in this context we are looking at star sized lenses and trying to explain a method to quantify what the distortions are from within a "heliosphere" (sun bubble)


when measuring distance (or perceived distance)
from the changing shape (apparent) depending on our position relative to centre of the bubble.

xploder