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In 2004 the AAVSO conducted two intensive observing campaigns of peculiar Cataclysmic variables. BZ UMa was observed for four nights in outburst in February and again for two nights in quiescence in April. Results do not support its official classification as a UGSU star. Var Her 04 was discovered in late June and observed for about a month. Originally suggested as a rare UGWZ type star, its classification is also in doubt. We present early results from and lessons learned during these two campaigns.

2:00-2:30 Dale E. Mais
"Mira Variable Stars: Spectroscopic and Photometric Monitoring of this Broad Class of Long Term Variable and Highly Evolved Stars"

Mira variable stars are a broad class of stars, which encompass spectroscopic classes of type M, S and C. These stars are closely related in terms of their long term variability, position on the Hertzsprung-Russell diagram their intermediate mass (from -0.8 to -8 solar mass) and the fact that class M evolves into the S and C type stars as certain stages of shell burning around the core proceeds. These shell burning episodes produce heavy elements beyond iron and also carbon which can appear at the surface of these stars during periods of convective instability resulting in greatly enhanced abundances of elements beyond the iron group and an increase in the carbon/oxygen ratio. In addition, it is known that these type stars, in particular, the M type Mira's can flare up over periods of hours to days by several tenths of a magnitude all the way up to 1 magnitude. The spectroscopic changes, which occur during these flare episodes, no doubt related to their core burning evolution, remain relatively unexplored but are possibly coupled to changes in the molecular opacities of molecules such as TiO and possibly ZrO in the case of S and C type stars. This project was initiated in order to monitor a group of program stars of these classes in the V and R photometric bands in the hopes of "catching" some of these stars during one of these flare ups and thus to be able to conduct spectral analysis of the flare-ups in real time and compare these spectra to the non-flare spectra.

This talk will describe the background of these type stars, in particular, their evolutionary history, their spectroscopic differences. In addition, the strategies and initiation of this project will be described.

2:30-2:50 Poster Paper Introductions:
"The Rice University CCD Imager for the AEOS Telescope" R.I. Dufour
"Deep Impact Mission" Mary Ann Kadooka
"Gamma-ray burst optical afterglow observations of Nyrola Observatory" Arto Oksanen
"Analyzing Online Data on Variable Stars: An Authentic Research Experience for Teachers" Pebble Richwine

3:20-3:40 Elizabeth Waagen
“The AAVSO Data Validation Project: Opening the Treasure Chest”

The AAVSO International Database contains over 11 million mostly visual observations of over 5,000 known and suspected variable stars contributed by over 6,000 observers worldwide since 1911 (the data for some stars go back earlier, even to the late 1800's).

Late AAVSO Director Janet Mattei liked to describe the AAVSO International Database as a treasure chest just waiting to be opened and explored. Not having the data validated (checked for transcription and digitization errors and quality- control checked) made accessing the "treasure" slow and sometimes very slow for researchers, despite our best efforts to provide the data quickly.

Of the 11+ million observations, 9.5 million are being validated by AAVSO Headquarters technical staff and released for downloading from the AAVSO website, thanks to Janet's planning and a 2-year grant from NASA. When the project (presently over 81% completed) is finished in the fall of 2004, the data will be placed on Caltech's NASA/IPAC-IRSA site and in other NASA databases so that the data are publicly available and may be used for astronomical research, education, and public outreach.

This paper addresses the questions: what is validation? why is it necessary? how is it done? and shows several examples of the "treasure" becoming available to everyone.

3:40-4:00 Matthew Templeton
"Secular Evolution in Mira Variables"

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Stellar evolution theory predicts that stars on the asymptotic giant branch (AGB) undergo a series of short thermal pulses that significantly change the luminosity and mass of the star on timescales of a few thousand years. These changes may be observable as changes in period in pulsating AGB stars such as the Mira and semiregular variables. It is know that a small fraction of these stars exhibit secular period change. In our project, we examined the light curves of 547 Mira variables from the AAVSO International Database to search for and quantify these secular changes. Approximately 10 percent of stars showed evidence of secular period change at the two sigma level, and eight stars showed large period changes at the six sigma level or greater. The largest measured values of dlnP/dt are consistent with those predicted to occur during thermal pulses on the AGB. A number of other stars exhibit non-monotonic period change on long timescales, the cause of which is not yet understood. In the overwhelming majority of cases, the period variations appear to be small and essentially random.

4:00-4:30 Tim Castellano
"Transitsearch: A Collaboration with AmateurAstronomers to Discover Transiting Extrasolar Planets"

The discovery of more than 100 planets around nearby solar-like stars that surpass Jupiter in size yet orbit their stars more quickly than Mercury has heralded a new era in astronomy. These enigmatic "Hot-Jupiters" are large enough and close enough to their parent stars that their "transits" can be captured by astronomers equipped with a small computer controlled telescope and a quality electronic CCD camera. The first known transiting extrasolar planet HD 209458b, in the constellation Pegasus, has been the subject of hundreds of scientific papers since its discovery in 1999. The transit of 8th magnitude HD 209458 has been observed by at least a dozen non-professional astronomers using telescopes as small as 4 inches in aperture. Using equipment already in hand, and armed with target lists, transit time predictions, observing techniques and software procedures developed by the transitsearch, collaboration non- professional astronomers can contribute significantly to the study of extrasolar planets by carefully measuring the brightness of stars with known Hot-Jupiters. In this way, amateur astronomers may resume, after a two century interruption, the tradition of planetary discoveries begun with William Herschel's 1787 discovery of the "solar" planet Uranus.

To date, transitsearch has amassed more than 50 interested observers in 10 states and 12 countries and provided research experience for undergraduate and graduate students from California, Washington, Michigan and North Carolina. A status report on the successes and challenges of a highly collaborative yet widely distributed project with participants of varying background and equipment levels will be discussed.

Exciting upcoming opportunities for transitsearch observers to compete for time on NASA's SOFIA aircraft as outreach partners will be discussed and plans for this summer's observing campaign to expand our network of qualified observers through additional measurements of HD 209458b and hands-on workshops will be outlined.

4:30-5:00 Donna Young
"Double Vision: Chandra and AAVSO"

The Chandra X-Ray Observatory is the most sophisticated X-ray observatory launched by NASA. Chandra is designed to observe X-rays from high-energy regions of the universe, such as the remnants of supernovae explosions, colliding galaxies, black holes, pulsars, neutron stars, quasars, and X-ray binary stars. The spectacular results from the first five years of Chandra observations are changing and redefining theories with each observation. Every exciting new image shows glimpses of such exotic phenomena as super-massive black holes, surprising black hole activity in old galaxies, rivers of gravity that define the cosmic landscape, unexpected x-ray activity in proto-stars and failed stars, puzzling distributions of elements in supernovae remnants, the sound waves from a super-massive black hole, and the even the tantalizing possibility of an entirely new form of matter - the strange quark star. On September 14, 2000, triggered by alerts from amateur astronomers worldwide, Chandra observed the outburst of the brightest northern dwarf nova SS Cygni. The cooperation of hundreds of amateur variable star astronomers and the Chandra X-Ray scientists and spacecraft specialists provided proof that the collaboration of amateur and professional astronomers is a powerful tool to study cosmic phenomena. .