图片说明: The Summer Triangle Over Catalonia
Explanation: Can you find the Summer Triangle? It's not hard to find this famous triangle of stars this time of year from northern locations. Just look straight up after sunset and find three of the brightest stars in the sky that nearly form a triangle. Then compare these stars to sky images like the one shown above, or hold up a smart phone running a good sky labelling application. The three stars that form the vertexes of the Summer Triangle are Vega, Deneb, and Altair. Pictured above is a 360 degree full sky projection framing not only the Summer Triangle but the great arch of our Milky Way Galaxy. The image was taken last week in front of a small river that encircles the historic town of Sant Llorenç de la Muga in Catalonia, northeastern Spain.