Starship Asterisk*

Ann wrote:

epitalon wrote:
Do we happen see many streams of galaxy that are not aligned with our's ?
To me, the most interresting point is : Is our galaxy the center of the universe ?

We humans are at the center of our own universe. From our own vantage point, everything seems to point in our direction.
Ann

Diocoles wrote:If space is being created constantly, then the space for expansion is expanding equally in all directions.

Chris Peterson wrote:

DavidLeodis wrote:It's a fascinating image, in which there also seems to be a lot of galaxies.

I wonder if there is a theoretical limit on the numbers of galaxies despite there being a lot of space in 'Space'?

Assuming that there isn't an infinite amount of space, we can safely say there are a finite number of galaxies. And in fact, we can reasonably estimate the number of galaxies in the observable universe (or in any particular volume of the entire universe).

DavidLeodis wrote:It's a fascinating image, in which there also seems to be a lot of galaxies.

I wonder if there is a theoretical limit on the numbers of galaxies despite there being a lot of space in 'Space'?

Ann wrote:

epitalon wrote:
I understand that galaxies and clusters are aligned along filaments. If those filaments are pointing toward our galaxy... there is most chance to find a galaxy behind a cluster of galaxies.
But am I right when I write that all filaments point toward our galaxy ?
Do we happen see many streams of galaxy that are not aligned with our's ?

To me, the most interresting point is : Is our galaxy the center of the universe ?

Click to view full size image

A portion of the universe.
Where are we?

We humans are at the center of our own universe. From our own vantage point, everything seems to point in our direction.

If we lived in another galaxy in another part of the universe, we would experience the universe in exactly the same way as we do now. We would still be the center of our own universe. From our own vantage point in that other galaxy in that other part of the universe, everything would still seem to point in our direction.

So is the Milky Way the center of the universe? If we could "step back" and watch the observable universe in its current perhaps 96 billion light-years diameter, the Milky Way would be utterly insignificant and nowhere near a "center of the universe".

Ann

epitalon wrote:To me, the most interresting point is : Is our galaxy the center of the universe ?

Animal of Stone wrote:If the Milky Way is not the centre of the universe, is there a way to determine where in the scheme of matter we are placed ? And further can we pinpoint the direction of the centre of the cosmos ?

epitalon wrote:
I understand that galaxies and clusters are aligned along filaments. If those filaments are pointing toward our galaxy... there is most chance to find a galaxy behind a cluster of galaxies.
But am I right when I write that all filaments point toward our galaxy ?
Do we happen see many streams of galaxy that are not aligned with our's ?

To me, the most interresting point is : Is our galaxy the center of the universe ?

Chris Peterson wrote:

Boomer12k wrote:Thus, while there are lots of images and examples, it takes special circumstances, and those are rather rare.

Of course, it depends on how you choose to define "common" (or "rare"). There are dozens (or even hundreds) of examples of visible lensed structures (but of course, take a narrow field image in any random direction and the odds are you won't have one in the image). But make any image near a galaxy or cluster of galaxies, and there's a good chance that you'll be able to measure lensing instrumentally- a technique that is used to map dark matter distributions. Lensing also shows up in photometric data, where single lensing objects briefly modulate the background light.

Chris Peterson wrote:

Guest wrote:As for the comments about the frequency of gravitational lensing. I think our perception is governed only by our position near the focal point of such a lenses, and it probably happens all over the place but we just can't perceive or appreciate it. I wonder, tho, if we were really near the focal point (as if that could really happen), would the image be really clear or still a bit fuzzy?

There is no focal point as such, because gravitational lenses are optically different than the sort of lenses we are generally familiar with. They work "backwards": they deviate light most at their centers, and less as you move radially outwards. What this means is that the (distorted) object will be seen if the observer is anywhere along a line that passes through both the object and the lens.

APOD Robot wrote:seen through the looking glass

Boomer12k wrote:Thus, while there are lots of images and examples, it takes special circumstances, and those are rather rare.

Guest wrote:As for the comments about the frequency of gravitational lensing. I think our perception is governed only by our position near the focal point of such a lenses, and it probably happens all over the place but we just can't perceive or appreciate it. I wonder, tho, if we were really near the focal point (as if that could really happen), would the image be really clear or still a bit fuzzy?

ta152h0 wrote:How do you find these things ? incredible luck or a series of events ?