NASA's SPHEREx observatory will map the entire sky to help scientists answer big-picture questions about the origins of our universe, galaxies, and key ingredients for life in our galaxy, such as water. Operating from low Earth orbit, the telescope will sweep across the sky, taking about 600 exposures each day. Using a technique called spectroscopy, the observatory will image every section of the sky 102 times, each time using a different color filter that blocks all wavelengths except one. By combining those images, the mission will produce a map containing information about the composition of and distance to millions of stars and other objects in our galaxy and hundreds of millions of galaxies beyond. (See an animation of this process, depicted in a still artist's concept above, at spherex.caltech.edu/video/all-sky-survey.) Short for Spectro-Photometer for the History of the Universe, Epoch of Reionization and Ices Explorer, SPHEREx will help scientists study what happened in the first fraction of a second after the big bang, how galaxies formed and evolved, and the origins of water in planetary systems in our galaxy. https://photojournal.jpl.nasa.gov/catalog/PIA26533