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10/11/2012 – Ephemeris – North American Nebula
Ephemeris for Thursday, October 11th. The sun will rise at 7:53. It’ll be up for 11 hours and 10 minutes, setting at 7:04. The moon, 3 days past last quarter, will rise at 4:30 tomorrow morning.
Most of what we see in the Milky Way are just masses of stars, but there are bright clouds of gas , or to name them properly: emission nebulae. These bright clouds are areas of star formation. It is the ultraviolet light from young massive stars that light up the clouds they were formed from. A bright one, easily visible in binoculars is just about overhead at 9 p.m. Called the North American Nebula, a glow shaped much like our continent just east of the star Deneb, the northernmost star of the Summer Triangle, and brightest star in Cygnus the swan or Northern Cross. There are many other nebulae in the Milky Way, visible in binoculars and small telescopes. Many enjoyable hours can be spent sweeping the Milky Way for nebulae and star clusters.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
North American Nebula in Red. My old image.
The red object is the North American Nebula. Our eyes cannot perceive the color, due to hydrogen. This was a time exposure on film without telephoto. The bright star to the upper right is Deneb. The orientation is approximately correct if facing south. The photo also shows the stars that make up the glow of the Milky Way to the unaided eye.
Deneb Overhead at 9 p.m. on October 11. Created using Stellarium.
The North American Nebula is about the size and position of the C in Cygnus.
Better view of the North American Nebula taken by Scott Anttila.
This nebula is cataloged as NGC 7000.
09/29/11 – Ephemeris – Deneb at the zenith
Thursday, September 29th. The sun will rise at 7:37. It’ll be up for 11 hours and 49 minutes, setting at 7:27. The moon, 2 days past new, will set at 8:28 this evening.
At 10 p.m. tonight the first magnitude star Deneb will be overhead, that is very near the zenith. Deneb is the northern most and dimmest of the three stars of the Summer Triangle. It is at the head of the Northern Cross, which extends to the south. This is an asterism, which is what astronomers call a informal constellation. The Big and Little Dippers are also examples of asterisms. You won’t find them in the list of the 88 official constellations. The actual constellation that Deneb belongs to is Cygnus the swan. In the swan Deneb is the tail. That’s actually what Deneb means. The swan is flying southwestward along the Milky Way with its wings outstretched. Stars can be followed around the wings to make out a very realistic flying swan.
* Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Deneb at the Zenith. Looking overhead while facing south. Created using Stellarium.
The Summer Triangle of bright stars Deneb, Vega and Altair are in this view.
Bob Moler's Ephemeris Blog 