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42 ASTRO PUBLISHING The image was taken with one of the highest-performance wide-field imaging instruments in the world, the Dark Energy Camera (DECam). This instrument is perched atop the Víctor M. Blanco 4-meter Telescope and its vantage point allows it to collect starlight reflected by the telescope’s 4-meter-wide (13-foot- wide) mirror, a massive, aluminum- coated and precisely shaped piece of glass roughly the weight of a semi truck. After passing through the optical innards of DECam — including a corrective lens nearly a meter (3.3 feet) across — starlight is captured by a grid of 62 charge-coupled de- vices (CCDs). These CCDs are similar to the sensors found in ordinary digital cameras but are far more sensitive, and allow the instrument to create detailed images of faint astronomical objects such as NGC 1512 and NGC 1510. Large astronomical instruments such as DECam are custom-built masterpieces of optical engineer- ing, requiring enormous effort from astronomers, engineers, and technicians before the first images can be captured. Funded by the US Department of Energy (DOE) with contributions from international partners, DECam was built and tested at DOE’s Fermilab, where sci- T he barred spiral galaxy NGC 1512 (left) and its diminutive neighbor NGC 1510 were cap- tured in this observation from the Víctor M. Blanco 4-meter Telescope. As well as revealing the intricate in- ternal structure of NGC 1512, this image shows the wispy outer ten- drils of the galaxy stretching out and appearing to envelop its tiny companion. The starry stream of light that connects the two galaxies is evidence of the gravitational in- teraction between them — a stately and graceful liaison that has been going on for 400 million years. NGC 1512 and NGC 1510’s gravitational interaction has affected the rate of star formation in both galaxies as well as distorting their shapes. Eventually, NGC 1512 and NGC 1510 will merge into one larger galaxy — a drawn-out example of galactic evolution. These interacting galax- ies lie in the direction of the con- stellation of Horologium in the southern celestial hemisphere and are around 60 million light-years from Earth. The wide field of view of this observation shows not only the intertwined galaxies, but also their star-studded surroundings. The frame is populated with bright foreground stars within the Milky Way and is set against a backdrop of even more distant galaxies. Galactic ballet captured by DECam by NOIRLab Amanda Kocz