Before sunup on March mornings, look for the Summer Triangle. Although it’s not summer at our northern latitudes, the Summer Triangle’s three bright stars – Vega, Deneb and Altair – are visible now in the east before sunrise. They’re all 1st-magnitude stars and the brightest stars in their constellations: Vega in Lyra the Harp, Deneb in Cygnus the Swan and Altair in Aquila the Eagle.
The Summer Triangle isn’t one of the officially recognized 88 constellations. Like the Big Dipper, it’s what’s called an asterism, a pattern of stars that’s easy to pick out.
For much of the Northern Hemisphere, the Summer Triangle stars are up for at least part of the night every night of the year. Are you in the Southern Hemisphere? You probably won’t see the entire Summer Triangle yet before sunup from your part of the world. The star Deneb will probably be lost in the glare of sunrise at southern temperate latitudes.