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The primary goal of this study is to observe how complex the behaviors ofCepheids can be, and to show how the continued monitoring of Cepheids atmultiple wavelengths can begin to reveal their "secret lives."  We aim to achieve this through optical photometry, UV spectroscopy and X-rayimaging. Through Villanova's guaranteed access to ground-based telescopes, wehave secured well-covered light curves as regularly as possible. Amplitudes andtimes of max brightness were obtained and compared to previous literatureresults. At UV wavelengths, we have secured hi-res spectra of 2 nearby Cepheids- delta Cep and beta Dor - with HST-COS. Also, we have obtained X-ray images of5 Cepheids with XMM-Newton and the Chandra X-ray Observatory, and furtherobservations with both satellites have been proposed for (XMM) and approved(Chandra).  Optical photometry has shown that 8 of the 10 observed Cepheids haveamplitude variability, or hints thereof, and all 10 show period variability(recent, long-term or possibly periodic). The UV spectra reveal emission linesfrom heated atmospheric plasmas of 10^4 - 10^5 K that vary in phase with theCepheid pulsations. The X-ray images have detected the three nearest Cepheidsobserved (Polaris, delta Cep and beta Dor), while the distances of the othertwo place their fluxes likely at or below detector background levels. The X-rayfluxes for delta Cep show possible phased variability, but anti-correlated withthe UV emission lines (i.e. high X-ray flux during low UV flux, and viceversa).  Further data are required to ultimately confirm Blazhko-like cycles inCepheids, X-ray variability with phase and the particulars of the high-energyvariability such as phase-lags between atmospheric plasma emissions ofdifferent temperature and the exact contributions of the possible heatingmechanism.

The Secret Lives of Cepheids: A Multi-Wavelength Study of the Atmospheres and Real-Time Evolution of Classical Cepheids