The smaller of the two irregular galaxies that accompany our Galaxy; also known as the Nubecula Minor. It is about 9000 l.y. across and some 200 000 l.y. away, visible to the naked eye as a misty patch about 3° across in Tucana. Its visible mass is less than 2% of our Galaxy’s, and it contains relatively more gas and less dust than the Large Magellanic Cloud (LMC), but fewer clusters and nebulae. Its structure may be elongated along the line of sight to Earth. Like the LMC, the SMC shows evidence for star formation early in its history, followed by a lull, and then a more recent burst. The stars and interstellar matter have a lower abundance of heavy elements (from one-quarter to one-tenth) than the stars in our local neighbourhood of the Galaxy. See also magellanic clouds.