Photometric Surveys

In contrast to spectroscopic surveys, which provide exquisite data on relatively small numbers (millions) of stars, photometric surveys provide rough information on much larger samples of stars, numbering into the billions (a few percent of the total stellar population of the Galaxy). MPIA is an international partner in the upcoming LSST survey (2023-), which will image the entire observable Southern sky every few nights, using a new 8-metre telescope on Cerro Pachon, in Chile. LSST will provide deep, multi-band, multi-epoch photometry across more than half of the Milky Way disc, allowing study of Galactic structure, as well as transients and variable stars in the Galaxy. The MPIA is also involved in a number of smaller photometric surveys, including GALACTICNUCLEUS, focused on the Milky Way bulge, and the Dark Energy Camera Plane Survey (DECaPS), which has gathered deep optical and near-infrared photometry of over 2 billion stars in the Southern Galactic plane.