LVAAS - THE LEHIGH VALLEY AMATEUR ASTRONOMICAL SOCIETY: Promoting, Facilitating and Teaching Astronomy Since 1957

Welcome to LVAAS, Anonymous
Tuesday, January 23 2018 @ 10:36 PM EST



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LVAAS General Meeting

Sunday, February 11 at 2:00 p.m. in the Trumbower Science Building, Muhlenburg College, Allentown, PA

"Unfolding Mysterious Evolution of Cepheids"

Krittanon "Pond" Sirorattanakul
President, Lehigh University Astronomy Club


Cepheids are a type of variable stars in which a star's brightness changes through time as a result of a type of pulsations in the star. The period of the brightness variation can be used to determine the star's luminosity, which can inform us about the distance between the Cepheid and the Earth. Because of this Period-Luminosity relationship, Cepheids are used to determine the distance to other galaxies. However, the period of pulsation of many Cepheids is itself changing noticeably, complicating the accuracy of the Period-Luminosity relationship. This talk will examine how we might solve this enigma through understanding the evolution of a Cepheid’s internal structure.



—    LVAAS    —

THE LEHIGH VALLEY AMATEUR ASTRONOMICAL SOCIETY -- 620B East Rock Road -- Allentown, PA 18103 -- 610-797-3476 --


Founded in 1957, the Lehigh Valley Amateur Astronomical Society (LVAAS) is one of the oldest continuously-operating amateur astronomy organizations in the U.S. The mission of LVAAS is to promote the study of Astronomy and to maintain a meeting space, observatories, and a planetarium.

LVAAS operates two astronomy sites: The South Mountain site in Salisbury Township is the headquarters of the Society. It has a planetarium with a Spitz A3P projector, a 21 foot dome, meeting space, the Red Shift store, library, workshop space, and three observatories. The Pulpit Rock site near Hamburg is LVAAS's members-only dark sky site. At 1600 feet above sea level, the site features five observatories and a pad for member's scopes.

Members who receive training on the scopes may obtain keys to the observatories. LVAAS also maintains a rental "fleet" of telescopes that members may rent at low cost. Members also receive access to The Observer, our online newsletter, as well as reduced subscription prices to Sky and Telescope and Astronomy Magazine. If you want to learn more about astronomy and LVAAS, please join us at our next public star party.


South Mountain Clear Sky Chart  image

Pulpit Rock Clear Sky Chart         image

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