More than 12 billion years of cosmic history are shown in this panoramic, full-color view of thousands of galaxies in various stages of assembly.
This image was taken by NASA’s Hubble Space Telescope.
The image reveals galaxy shapes that appear increasingly chaotic at each earlier epoch, as galaxies grew through accretion, collisions, and mergers. The galaxies range from the mature spirals and ellipticals in the foreground, to smaller, fainter, irregularly shaped galaxies, most of which are farther away, and therefore existed farther back in time. These smaller galaxies are considered the building blocks of the larger galaxies we see today.
The image shows a rich tapestry of 7,500 galaxies stretching back through most of the universe’s history. The closest galaxies seen in the foreground emitted their observed light about 1 billion years ago. The farthest galaxies, a few of the very faint red specks, are seen as they appeared more than 13 billion years ago, or roughly 650 million years after the Big Bang. This mosaic spans a slice of space that is equal to about a third of the diameter of the full Moon (10 arc minutes).
The new Hubble view highlights a wide variety of stages in the galaxy assembly process. Ultraviolet light taken by WFC3 shows the blue glow of hot, young stars in galaxies teeming with star birth. The orange light reveals the final buildup of massive galaxies about 8 to 10 billion years ago. The near-infrared light displays the red glow of very distant galaxies — in a few cases as far as 12 billion to 13 billion light-years away-whose light has been stretched, like a toy Slinky, from ultraviolet light to longer — wavelength infrared light due to the expansion of the universe.
In this ambitious use of Hubble’s observing time, astronomers used 100 Hubble orbits to make the ACS optical observations of this slice of the GOODS field and 104 orbits to make the WFC3 ultraviolet and near-infrared exposures. This set of unique new Hubble observations reveals galaxies to about 27th magnitude in brightness.
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