Right through the dipper!

Photo: Arc of the International Space Station passing through the Big Dipper. Credit: Chris Christie.
The ISS passed through the “Big Dipper” August 23, 2012. Photo by Chris Christie.

There was a bright, beautiful pass by the International Space Station the night of August 23, 2012. Alerted by CAA member Jay Reynolds, fellow member Chris Christie set up his camera and got an excellent shot of the station’s arc. That night’s pass was of the “fading” type; the space station rises above the horizon reflecting sunlight and, due to the Sun’s angle and the projection of Earth’s shadow into space, crosses into that shadow while still very high in the sky. The path of the ISS, as viewed from Northeastern Ohio, took it right through the Big Dipper asterism. Light pollution provides color above the horizon. Christie’s photo data: Canon EOS Rebel T3: ISO 800, f/3.5, 18mm, 55-second exposure started at 9:39 PM.

Splendid photo of the space station

Photo: Starry background with streaking space station trail 8-6-2012. Credit: Dave Nuti.
The ISS crosses the sky in brilliant fashion in this image by Dave Nuti.

CAA member Dave Nuti was all set to photograph a brilliant pass of the International Space Station visible from Northeastern Ohio the night of August 6, 2012. The pass was to take the ISS across an area near the heart of the Milky Way as seen from here. Nuti’s result was a splendid view of the night sky, galactic star clouds floating, dotted by suns closer in. The image even captured bright patches — star clusters in our galaxy — on that clear night. Constellation fans will notice the “teapot” of Sagittarius just to the left of center, and the stars of Scorpius spanning the left side of Nuti’s picture.

Technical Info — Nikon D70: ISO 1600, f/4.5, ~45 seconds, 20mm, August 6, 2012, from Letha House Park, near Spencer, Ohio. Photo by Dave Nuti.

A summer gem

by Bill Murmann

Image: Star chart showing constellation Cygnus.
Constellation Cygnus with Albireo circled at the Swan's head. Image via Stellarium by James Guilford.

During the summer, one of the best colorful double stars is Albireo, the head of the “Swan” in the constellation Cygnus. “Double Stars” was the topic for the program at our monthly meeting on Monday, September 12, and Albireo is a great example. Albireo is 380 light years away; the pair of stars is designated “Albireo A” and “Albireo B.”

Albireo A is yellow star, slightly cooler than our Sun. It has a surface temperature estimated at 7,000 degrees F., compared to the Sun’s 9,000-degree F. surface temperature.

Its companion, Albireo B, is a hot, blue star with an estimated surface temperature of about 23,000 degrees F. It also rotates very fast — at about 560,000 MPH.

When we are looking at Albireo, we are actually seeing three stars. Albireo A is, itself, a close binary star. Most of us, however, can’t split this pair with our telescopes. It takes a minimum 20-inch telescope under really good sky conditions to split Albireo A. Paul Leopold with his 20-inch scope is probably the only CAA member who has a chance to see all three stars in Albireo.

A summery triangle

Image: Map depicting summer's triangle of stars.
The Summer Triangle - by James Guilford using Stellarium and Adobe Photoshop

by William Murmann

During the summer months, stargazers can see the famous Summer Triangle almost directly overhead. The triangle is a giant asterism created by drawing imaginary lines between three bright stars — Deneb in the constellation Cygnus, Vega in the constellation Lyra, and Altair in the constellation Aquila.

Deneb is a blue-white super-giant that is almost 200 times larger than the Sun and 60,000 times brighter. At 1,500 light years distant, it is one of the most luminous stars known and is the farthest first-magnitude star from Earth. It has a solar wind that is 100,000 times faster than the solar wind from the Sun.

Vega is a blue-tinged white star that is about 25 light years away. It is twice the mass of the Sun and about 37 times brighter. At 16,000-degrees F, its surface temperature is almost twice as hot as the surface of the Sun. With the exception of the Sun, Vega is the first star to have been photographed. In 14,000 years, it will replace Polaris as our north star.

Altair, at a distance of 16.9 light years is about 1.5 times larger than the Sun, and is one of the closest stars visible to the naked eye. Altair spins on its axis at about 640,000 mph and completes a full revolution every 6.5 hours. The Sun in comparison takes about 25 days to complete one revolution, as measured at its equator. Altair is spinning so fast that its north and south poles are pushed in, giving the star an oblate appearance.

The Summer Triangle was first described as a triangle by Austrian astronomer J.J. Littrow in his atlas in 1866. German astronomer Johann Bode connected the stars in a map in 1816, but did not label the asterism.