R Coronae Borealis
It is one of the three brightest R Coronae Borealis stars visible to Earth observers, along with R Coronae Borealis and V854 Centauri, and the brightest in the southern hemisphere. It is also a pulsating variable, with a semiregular period of 38 days. Its light curve has been studied for over a hundred years and is typical for the class, characterised by a sudden drop in brightness of several magnitudes over a few weeks before gradually brightening over the following several months. The timing between these dimmings is irregular. The cause of the drop in magnitude is the presence of dust clouds of carbon obscuring (and most likely ejected from) the star, though the mechanism how this might occur is not known. Extensive clouds have been detected with ESO's Very Large Telescope Interferometer.