SIMBAD references

Recent study of SDSS J1257+3419 has revealed that this stellar system is either a faint and small dwarf galaxy or a faint and widely extended globular cluster. In this short note, the author suggests that this system is one of the smallest dwarf spheroidals (dSphs) in the Milky Way. We re-examine some observational quantities of this object and check whether it can be bound system. As a result, we find the mass of SDSS J1257+3419 is the lowest of dSphs in the Milky Way, and its mass density is typical of dSphs. Important is that the tidal radius of SDSS J1257+3419 is much larger than its half-light radius. That is, this very small dSph can be bound by its own gravity.