After observing 1405 nights for 6 years, astronomers at three observatories made an image of the sky containing 10 billion pixels of data and depicting more than a billion galaxies. The bad astronomer Phil Plait contains the details.
This is the result of the DESI Legacy Imagining Surveys, maps of the sky made by the three observatories (the Dark Energy Camera Legacy Survey, the Beijing-Arizona Sky Survey, and the Mayall z-band Legacy Survey, in combination with the orbiting WISE infrared. observatory). They mapped the northern sky in seven colors and covered a third of the entire sky – 14,000 square degrees, or the equivalent area of 70,000 full moons in the sky.
The ultimate goal is to better understand dark energy, the mysterious substance that accelerates the expansion of the universe by looking at the distribution of galaxies throughout the universe. They will do this by selecting tens of millions of the billion galaxies in the data and obtaining follow-up observations using the Dark Energy Spectroscopic Instrument (DESI), which will take the galaxies into spectra and find their distances.
Since we will know their positions in the sky and their distances, it will make a 3D map of the universe bigger than ever before.
The photo at the top of the post is just a tiny bit of the complete picture – you can slide the whole thing into this viewer and zoom in. Make sure you zoom out in increments from the standard view to fully realize how absurdly large this image (and the universe) is.
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