Spitzer’s Last Look at the Small Magellanic Cloud

The Spitzer Space Telescope surveyed the Small Magellanic Cloud (SMC) and its surroundings in Cycle 13 in two epochs from 2017 to 2018 at 3.6 and 4.5 um. The SMC, with a metallicity between 0.1 and 0.2 Solar, is the nearest metal-poor galaxy we can observe with an unobscured view. The new survey data cover about 30 square degrees and include the Bar and Wing of the SMC and the Bridge toward the LMC. The combined Spitzer surveys of the SMC now span a temporal baseline of nearly 13 years in the core of the SMC and nearly 10 years across the entire galaxy. These datasets open up a range of topics for investigation, including transient phenomena in young stellar objects in the SMC and in background galaxies, the detection of foreground brown dwarfs from their proper motion, and the study of deeply embedded evolved stars that cannot be observed with current optical and near-infrared temporal surveys. Combined with the shallower survey data from the Wide-field Infrared Survey Experiment (WISE), we now have 23 epochs in two infrared filters from 2005 through 2019. This work is supported by NASA Award 80NSSC19K0585.