Maybe you noticed it on fireworks night. High overhead after dusk, a bit toward the southwest, shines a bright star tinted like a drop of ginger ale. That’s Arcturus, the nearest orange giant. Don’t confuse it with Vega, very high toward the east, equally bright but icy blue-white. The colors are subtle but there if you look.
Very far below Arcturus, two more bright points await your view: the planet Saturn and, to its lower right, pale blue-white Spica. They form a long, very tall triangle. To astronomers, this bright summer threesome symbolizes three cutting-edge trends on the forefront of astronomy. Full story for BostonGlobe.com subscribers.