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Star of the National Park Service

Consider the star Ruchbah to be the "Centennial Star" of the National Park Service (NPS), which celebrates its 100th birthday in 2016. Ruchbah, in the constellation of Cassiopeia, is a variable star approximately 100 light years away. When the park system began on August 25, 1916, starlight left Ruchbah traveling at 186,000 miles per second, and that starlight is just now reaching our eyes.

The National Parks are supportive of the night sky, for the grandeur of a starry night is an integral part of the visitor experience. The Indiana Dunes National Lakeshore invites the public to join members of the Chicago Astronomical Society with their telescopes on Saturday, November 7, 2015, at the Kemil Beach access area at 5:00 p.m. Julie Larsen writes,

In celebration of the National Park Service centennial birthday and the semi centennial birthday of the Indiana Dunes National Lakeshore, every first Saturday of the month through November of 2016, telescopes of epic proportions will be on hand to view our night skies. At this time, the Milky Way galaxy crosses the night sky overhead from east to west. Skies providing, expect to see the Pleiades star cluster, the Double Cluster in Perseus, and the Andromeda Galaxy. Planets Uranus and Neptune are also visible in the southern sky.

The Kemil Beach access area is located one mile north and three miles east of the Indiana Dunes visitor center. The visitor center is located at the intersection of US Hwy 20 and US Hwy. 49 north of Chesterton, Indiana. For more information on this or other programs at Indiana Dunes National Lakeshore, call 219-395-1882 or check the park’s website at

The Indiana Dunes National Lakeshore is one of 408 units of the National Park System ranging from Yellowstone to the Statue of Liberty. Indiana Dunes National Lakeshore includes 15 miles of the southern shoreline of Lake Michigan and 15,000 acres of beach, woods, marshes, and prairie in the northwest corner of Indiana. More than 2 million visitors come to this national park each year.

Per Larry Silvestri, the address to plug into GPS is "Kemil Beach, Beverly Shores, IN 46304," or GPS Coordinates - 041.40.39N 087.00.35W. The map below showing Indiana Dunes National Lakeshore adjacent to Indiana Dunes State Park is at

Astronomer Dr. James Kaler describes the star Ruchbah (used with permission):

RUCHBAH (Delta Cassiopeiae). Among the most loved, most charming, and most visible of constellations is Cassiopeia, the celestial Queen. The five stars that make her familiar "W" (add one more to make her Chair) are circumpolar, always visible, from latitudes above 35 degrees north. Three of the W's stars carry classical proper names, Shedar (Alpha), Caph (Beta), and Ruchbah, the Delta star. (Gamma has no classical proper name, though "Navi" has been used in modern times.) And just over the line into third magnitude (2.68), Ruchbah is appropriately the fourth brightest star in the constellation, following right behind Gamma. The old Arabian astronomers commonly applied proper names to the stars according their positions within the classical figures, and "Ruchbah" is a fine example, the name a reduction of a longer phrase that refers to Cassiopeia's Knee. Just shy of Ruchbah, Delta Cas, lies both at the center of the picture and in the heart of Cassiopeia's delightful Milky Way. One hundred light years away, its light takes a century to come to Earth. A star with a temperature of 8400 Kelvin, a fair bit warmer than the Sun, it falls into mid-class A (A5). Stars produce radiation whose quality depends on temperature. Relative to what we see with our eyes, cool stars radiate vast amounts of invisible infrared, very hot stars a great deal of invisible ultraviolet, both of which must be factored in to estimate the star's true luminosity. White Ruchbah falls into a narrow temperature range where we simply do not have to worry much about either the ultraviolet or infrared, and little or no correction is needed, Ruchbah's luminosity 63 times solar. Marginally detected as a disk, the star is not quite four times the radius of the Sun and just barely classed as a giant, which means it has begun its death process, core hydrogen fusion shutting down. With a mass 2.5 times solar, this 600 million-year-old star will become a much larger orange giant in a mere 10 million years. Careful observations show that Ruchbah is slightly variable. Every 1.26 years it undergoes a partial eclipse when a small orbiting companion star, about which nothing is known, passes in front of it. Otherwise the star is quite normal, which makes it a good one against which to measure the properties of others. Ruchbah's greatest significance is that it provides a good background against which to study the local complex system of interstellar gas through which the Sun is now passing.

For other anniversary stars, see First Midnight, which recognizes the star Eltanin in Draco as South Bend's sesquicentennial star, and see Bicentennial Star, which recognizes the star Scheat in Pegasus as Indiana's bicentennial star.

[Added Nov.11, 2015]

Activity: Star Finder With Ruchbah

For a fun family activity, make a simple planisphere of three north circumpolar constellations to find the star Ruchbah. Print out both pieces of paper, and cut out the star circle with months around the perimeter. Fasten the star circle over the whole piece of paper with the horizon and hours labeled.

Notice how Cassiopeia with its Centennial Star Ruchbah can be used to find Polaris when the Big Dipper is low near the horizon. Cassiopeia is like a mirror image of the Big Dipper that serves a comparable north-finding function.

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