«What would it be like to fly through the universe? Possibly the best simulated video of this yet has been composed from recently-released galaxy data from the Sloan Digital Sky Survey. Every spot in the above video is a galaxy containing billions of stars. Many galaxies are part of huge clusters, long filaments, or small groups, while expansive voids nearly absent of galaxies also exist. The movie starts by flying right through a large nearby cluster of galaxies and later circles the SDSS-captured universe at about 2 billion light years (a redshift of about 0.15) from Earth. Analyses of galaxy positions and movements continues to bolster the case that our universe contains not only the bright matter seen, like galaxies, but also a significant amount of unseen dark matter and dark energy

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This image is a slice from a large simulation called ‘GiggleZ’ which complements the WiggleZ survey. It shows a snapshot of the large-scale matter distribution as studied in Morag Scrimgeour’s research. Image Credit: Greg Poole, Centre for Astrophysics and Supercomputing, Swinburne University (Phys.org) — We know that stars group together to form galaxies, galaxies clump to make clusters and clusters gather to create structures known as superclusters. At what scale though, if at all, does this Russian doll-like structure stop? Scientists have been debating this very question for decades because clustering on large scales would be in conflict with our ‘standard model‘ of cosmology. The current model is based on Einstein’s equations assuming everything is smooth on the largest scales. If matter were instead clumpy on very large scales, then the entire model would need to be rethought.