Lambda Scorpii star or as we know it, Shaula is a close double star! 

Last night I accompanied my friend doing an observation at the rooftop of astronomy building. After we assembled the telescope, we did the telescope alignment using several bright stars. Me and my friends sometimes use Shaula for telescope’s star alignment. For a long time, I never really know what kind of star Shaula is. :p

more on: David Darling, Constellations

source: 1, 2