The Summer Triangle — a shape made up of bright stars Vega, Deneb and Altair — is easily found in Bend’s night sky. Tonight, it is in the east about 40 degrees from the horizon. As the summer progresses, it will climb higher and higher, maintaining its position within the surrounding field of stars, and by late September the Triangle will appear in the west. Draw an imaginary line from Vega to Deneb to Altair and back to Vega and you have created the Triangle.

Apparent brightness is the luminance of objects as seen from Earth. The smaller the number, the brighter the object. Deneb produces 70,000 times the luminosity of our star, the sun. Still, Deneb does not appear spectacularly bright because Deneb is more than 3,000 light years away, much farther than either Vega or Altair. Each light year is an astounding distance of 5.9 trillion miles.

In astronomical parlance, an asterism is a grouping of stars that form a recognizable pattern in the night sky. Stars in constellations and asterisms are most often not related to each other physically, there being vast distances between them. They are simply visible in roughly the same direction. Asterisms may be composed of just part of a constellation. The Big Dipper, for example, is part of Ursa Major, the Great Bear. Alternatively, an asterism can be made up of portions of two or more constellations, as is the Summer Triangle (Altair, Deneb and Vega are the brightest stars in the constellations Aquila, Cygnus and Lyra).

Traveling a short distance from Bend to less light-polluted venues, Pine Mountain Observatory for instance, an observer will be treated to the Triangle’s magnificent surroundings. Moving forward from star Deneb, discover the Northern Cross, another asterism. Looking a bit farther out you will behold the entire constellation of Cygnus, the Swan, with outstretched wings beyond both sides of the cross. It is said that Cygnus flies amid the beautiful Milky Way, an ethereal band of pale light splashed across the entire sky. A truly inspiring sight, you are now looking through the disk of our own home galaxy.

— Kent Fairfield is a volunteer with Pine Mountain Observatory and a lifelong amateur astronomer. He can be reached at kent.fairfield@gmail.com. Other PMO volunteers also contributed to this article.