21 Comments
Sep 11Liked by Phil Plait

I definitely love a cool galactic cluster :)

One thing I noticed is that there does not seem to be much gravitational lensing visible in the image, even in the much larger one you pointed to. Is this because seeing that effect needs higher resolution imaging or do clusters like this need to be further away for us to see the gravitationally lensed galaxies (in other words, we are well inside the 'focal point' of the cluster)?

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Sep 11Liked by Phil Plait

Whoa -- mind-bending stuff for sure!

One thing I always wonder about when considering these extremely large megastructures: how they're even identified as structures in the first place. The analogy is to something like the kitchen countertop in this house -- it's polished faux granite, and visually just a chaotic mess o' speckles. No matter how far back I stand, or how close, I can't make out anything which looks like, uh, "clusters of speckle clusters." A given speckle might, on closer inspection, be revealed as a grouping of smaller speckles, and so on down (presumably) to the molecular/atomic level. But at really vast scales, like the ones astronomers must deal with... how do they know that Galaxies A, B, and C are roughly in the same neighborhood, and *remain* in the same neighborhood, so they can be considered members of the same cluster and not just apparently so?

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Sep 11Liked by Phil Plait

Amazing

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founding
Sep 11Liked by Phil Plait

Incredible Pic! (and at the "full image" (your link) it is just almost beyond comprehension). Like the Hubble deep field...

IC 4329A is "warped". Because of gravitional interaction its elliptical partner?

It is beyond impressive that we have the technology to "see" this marvel! And there is SO much there to study and learn from. An astronomer's dream, it is.

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Sep 11Liked by Phil Plait

Well, that puts things into perspective. Kinda makes a guy feel small and insignificant, and without much control over the Universe. 😂

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founding
Sep 12Liked by Phil Plait

What I always wonder, if why these clusters' masses are always expressed in solar masses. It always ends up as huge numbers which don't tell me a lot. Granted, nothing else probably would, but wouldn't it be at least more illustrative to use galaxy masses or something else that is in the same ball park?

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Sep 13Liked by Phil Plait

Slightly off-topic: What are those two swirly-looking objects to the upper-left of the elliptical? The upper one looks like a background spiral galaxy, but the lower one looks weird. And they are both similar in (apparent) size and brightness, almost like the lower one is a distorted reflection of the upper. Are these two gravitationally-lensed images of the same galaxy? Two galaxies colliding?

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