Tucana is a Southern Hemisphere constellation with several objects of interest. The constellation is southwest of Achernar, alpha Eridani.
Alpha Tucanae is the brightest star at a magnitude of 2.9. All other stars here are fourth and fifth magnitude or fainter. Alpha is found two binocular fields (about twelve degrees) due south of Alnair, alpha Gruis.
Beta Tucanae is a fine binocular double of two blue-white stars (b1 and b2): 4.4, 4.5; PA 170º and a separation of 27". The stars are east of alpha Tucanae a little over half way to Achernar and a bit to the south. While some observers have concluded that the third star here, b3, is not part of the binary system, others believe it in fact to be gravitationally bound to the other two. And in fact the most recent measurements show that it too is moving in the same direction, so we probably do have a triple system here.
47 Tucanae is such a large globular cluster it's gained the label of ‘47 Tuc’. Its official designation is NGC 104. The cluster is visible to the naked eye (and was therefore given the designation of a star in early star charts) and is considered one of the finest in the heavens, second only to the omega Centauri cluster. Although thousands of stars make up the cluster, the brightest are only 11th-magnitude. Thus it takes a medium to large sized telescope to begin to resolve its individual members. 47 Tucanae is found in the same region as the Small Magellanic Cloud (NGC 292), a vast nebulous oddly-shaped region to the south of the constellation.
