Hot air balloons inflate during the blue hour ... below the horizon but still provides enough light to make the sky appear ...

The pale sky was clear ... receding into a sea of blue, but it soon reached an altitude beyond the team’s ability to track with the naked eye. The High Altitude Balloon Experiments in Technology ...

He explains that outside the Earth’s atmosphere space looks black, but from the Earth’s surface the sky looks blue. He investigates this effect by launching a weather balloon. The helium ...