The Magellanic Clouds are a local laboratory for understanding the evolution and properties of dwarf irregular galaxies .
To reveal the extended structure and interaction history of the Magellanic Clouds we have undertaken a large-scale photometric and spectroscopic study of their stellar periphery ( the MAgellanic Periphery Survey , MAPS ) .
We present first MAPS results for the Small Magellanic Cloud ( SMC ) : Washington M , T _ { 2 } + DDO51 photometry reveals metal-poor red giant branch stars in the SMC that extend to large radii ( \sim 11 kpc ) , are distributed nearly azimuthally symmetrically ( ellipticity=0.1 ) , and are well-fitted by an exponential profile ( out to R \approx 7.5° ) .
An \sim 6 Gyr old , [ Fe/H ] \approx - 1.3 main-sequence turnoff is also evident to at least R =7.3° , and as far as 8.4 ^ { \circ } ~ { } in some directions .
We find evidence for a “ break ” population beyond \sim 8 radial scalelengths having a very shallow radial density profile that could be either a bound stellar halo or a population of extratidal stars .
The distribution of the intermediate stellar component ( 3 \lesssim R \lesssim 7.5° ) contrasts with that of the inner stellar component ( R \lesssim 3° ) , which is both more elliptical ( \epsilon \approx 0.3 ) and offset from the center of the intermediate component by 0.59° , although both components share a similar radial exponential scale length .
This offset is likely due to a perspective effect because stars on the eastern side of the SMC are closer on average than stars on the western side .
This mapping of its outer stellar structures indicates that the SMC is more complex than previously thought .