Our tour begins with Altair, which is the brightest star in Aquila. Aquila is the symbol of the ancient god Zeus. Aquila is an eagle which carries Zeus’ thunderbolts across the sky. The kite-shaped constellation is right in the middle of the Milky Way, which means it is teeming with star clusters and nebulae and well worth exploring with binoculars.
As darkness falls, Altair is visible 30 degrees above the northwestern horizon. The star is slightly hotter than the sun, with a surface temperature of roughly 7500°C. It shines white and is, by far, the brightest star in this part of the sky. By celestial standards, Altair is relatively close to us. Astronomers estimate its distance at a tad over 16 light years.
If you can access a telescope, it is worth pointing it towards the star Gamma Delphinus, the orange-gold star marking the dolphin’s mouth. This is one of the finest double stars in the heavens; even small telescopes show a secondary star with a lime green colour. This binary star system is about 125 light years from Earth and takes more than 3000 years to complete one orbit.
Once you have had your fill of celestial dolphins, there’s another small constellation to spot in this part of the sky. I’m talking about Sagitta, whose four brightest stars are directly below Altair. In Greek mythology, Sagitta is the arrow used by Hercules to kill the eagle trying to eat Prometheus.
