Karen Meech 20 minutes
"The Challenge of Finding the Comet for the Deep Impact Extended Mission"

The spectacular success of the Deep Impact mission coupled with adequate fuel reserves led to the authorization for the Deep Impact project to perform a maneuver on 2005 July 24 that would bring the flyby spacecraft back to the Earth's neighborhood in late 2007 for an extended mission to another comet. The goal of the extended mission will be to explore the diversity of comets, exploring the range of cometary topography, activity, thermal properties and chemistry. There were two possible comets accessible to the spacecraft: 103P/Hartley and 85P/Boethin. Of the two, 85P/Boethin is a much more desirable target. In order to re-direct the spacecraft to the comet, preparations for the December Earth-flyby maneuver are to begin with deep space maneuvers in early November 2007. On January 4, 1975, one day prior to its perihelion passage, short period comet 85P/Boethin was discovered by Reverend Leo Boethin in the Philippines. The comet was followed until early June. With an orbital period of 11.23 years, the comet was expected at its next perihelion passage in January 1986. It was recovered by Alan Gilmore and Pam Kilmartin in New Zealand on October 11, 1985 and followed just beyond its perihelion passage (Jan 16) until March 1986. Due to very poor observing conditions when the comet reached perihelion near superior conjunction, the comet was not observed during its most recent return to perihelion in April 1997. This comet gets bright enough for small telescope observations right near perihelion and the dust and gas coma and tail becomes visible approximately 3 months before perihelion. In order to fully map the orbit, observations are needed at 3 apparitions. This paper will discuss the role that small telescopes can play and will report on our attempts to recover this comet for a 3rd apparition, in what is turning out to be the most challenging comet recovery ever done, using most of the world's largest telescopes. We will know by Oct 19 if we have a mission target!

George H. Keel, Keith A. Graham, and Donald F. Collins 15 minutes
"Time series observations of IP Pegasi using an inexpensive ambient temperature CCD camera*"

IP Pegasi is an eclipsing cataclysmic variable star. The system occasionally goes into outburst due to accretion disk instabilities. Observations at quiescence were collected with a 20 cm aperture Schmidt Cassegrain Telescope. The images were recorded with a Meade DSI-Pro CCD camera. Co-adding was required to eliminate noise due to the ambient temperature CCD detector. The observations were unfiltered. AAVSO V-filtered and unfiltered observations were obtained during outburst. One objective of this study was to obtain time series photometric data from the low cost camera. This camera successfully provided unfiltered light curves of cataclysmic variable stars. A second objective was to analyze light curves of IP Pegasi and determine a probable structure of the system. The light curve during outburst displays a high luminosity midway between narrow eclipses. During quiescence, the peak intensity occurs just before the eclipse begins, and the eclipse is not symmetrical. The light curves support the belief that during outburst the brightest region lies in the vicinity of the white dwarf. During the quiescent state, the brightest regions of the system appear to be distributed among the red dwarf, the white dwarf, and the hot spot on the perimeter of the accretion disk.

* Funded by the American Astronomical Society: Small Projects Grant. Also funded by the North Carolina Academy of Sciences: Yarbrough Grant.

David Sliski 15 minutes
"On the Classification of V3798 Sgr"

In 1972 D. Hoffleit classified V3798 Sgr as an RV Tau variable star. However Springob et al. (1998) suggested that it could be an UXOR - a star with sporadic drops of brightness. A retrospective study of the variability of the star was conducted using the Harvard Plate Collection. More than 250 plates were looked at with more than 120 measurements made. The plates were exposed as early as 1895 and as late as 1949. In addition the star was monitored in BVRI with a CCD camera on the MMO's 24" telescope in 2007. In our study of V3798 Sgr, in both our CCD photometry and the plate study, sporadic drops of brightness were confirmed, measuring up to 1.3 magnitudes, within a broad range of time scales - from a year to an hour. No periodicity was detected. Spectra of the star showed typical early A absorption line spectrum with variable narrow emission in the cores of H-alpha and other absorption lines. A dramatic emission line flare was observed on September 19, 2007, with an increase of H-alpha equivalent width by a factor of 4 relative to the previous observation, five nights before. No continuum photometry is available for September 19 but the brightness in R two days before and one day after that date differs by only 0.07 magnitudes. A closer synchronism of spectroscopy and photometry is needed to verify the lack of correlation between the variations of the emission lines and continuum. So far, the lack of periodicity and an early spectral type seem to disprove the classification of V3798 Sgr as an RV Tau star and support the hypothesis that it is an UXOR. We thank A. Doane for help with measuring the plates and P. Berlind, M. Calkins and O. Shemmer for taking the spectra. This project was supported by the NSF/REU grant AST-0354056 and the Nantucket Maria Mitchell Association.

Kate Hutton, Arne Henden, and Michael Koppelman 15 minutes
"BVRI Photometry of CX Cephei (WR 151)"

The CX Cephei system is a double-line spectroscopic, eclipsing binary, consisting of an O5V and a WN5 (Woft-Rayet star) component. It has the second shortest known period (2.12691d) among O + WR binaries. The primary eclipse is shallow (approx. 0.1 magnitude) and the secondary eclipse even shallower. There is other variability also, accounting for a total range of approx. 12.0 to 12.2 in V. Lipunova & Cherepashchuk 1982 (Sov. Astron. 26:45-53) published photometry data from the 1980's. Lewis et al. 1996 (ApJ 405:312-326) published radial velocity data, showing that the WR star is in front at primary minimum. To this we add 340+ BVRI points over two years from the Sonoita Research Observatory (SRO), plus assorted time series from Sonoita (by HQA) and from Starhouse Observatory (by KMP). From our observations, we were able to 1) refine the period given by Lipunova & Cherepashchuk, and show that 2) there is intrinsic variability in addition to the eclipsing binary light curve, 3) that, unlike the 1980's, the secondary eclipse is now barely detectable, 4) there may or may not be additional "structure" in the eclipsing light curve, 5) and that the light curve varies with color. We see that the minima are pointed (eclipse not total), that the minima have a distinct beginning and end, although there are "shoulders" (ellipticity is important, but sky is seen between the stars at quadrature), that the eclipses are very shallow (low i, barely eclipsing). There is a dimward slope between phase 0.2 and 0.8, ranging from 2.5% in flux in B and V, to less than 1% in I. It seems unlikely that the WR core is substantially cooler than even an O5, so the primary minimum is expected to be at least partly an "atmospheric" eclipse caused by the WR wind (as Lipunova and Cherepashchuk modeled it), rather than the star itself. However, the primary minimum is one of the most stable features with time, so the wind opacity and configuration must not be responsible for observed changes. Changes in the secondary minima must be due to changes in what the O5 is eclipsing. We have not yet modeled all this!

Matthew Beaky 20 minutes
"Variable Star Spectroscopy: Tools, Techniques, and Recent Results"

For well over a century, variable star observers have catalogued changes in the brightness of thousands of variable stars. In contrast, there have been very few efforts to monitor changes in variable star spectra over time. This is unfortunate, because spectroscopic observations of variable stars can provide important additional information about the complex physical processes occurring within and around the star itself. For example, the presence of hydrogen emission lines in the spectra of Mira variables indicates the presence of shock waves in the upper atmospheres of these stars.

In this presentation, I will describe some of the resources available for making spectroscopic observations of variable stars with small telescopes, including spectrographs for data acquisition and software for data reduction and analysis. The process of observing a stellar spectrum will also be described, from image acquisition, through wavelength and flux calibration, to the extraction of stellar parameters such as spectral class and atmospheric composition. Finally, I will present results from ongoing research at the Truman State University Observatory to monitor spectral changes in Mira and semi-regular variable stars.

Edward J. Los 2 minute poster paper introduction
"The New DASCH Web Page"

DASCH is "Digital Access to a Sky Century at Harvard", the effort to digitize approximately 500,000 astronomical plates in the Harvard College Observatory collection. The project to date has generated 700 GB of images with 41 MB of supporting data. This paper describes a prototype web site designed to give researchers easy access to this information.

John R. Percy, Elena Favaro, Jou Glasheen, Bernadette Ho, and David G. Turner 20 minutes
"Period Changes in Pulsating Red Supergiants: A Science and Education Project"

Red supergiants are massive young stars, nearing the ends of their lives. They pulsate with amplitudes up to several magnitudes, with complex light curves whose basic time scale is consistent with radial pulsation. One of us (JRP), inspired by studies of red supergiant variability using AAVSO visual data by Kiss et al. (2006 MNRAS 372, 1721) and of BC Cyg using AAVSO visual data and HCO photographic data by Turner et al. (2006 PASP, 118, 1533), assigned the present project to co-authors EF, JG, and BH. They were participants in the University of Toronto Mentorship Program, which enables outstanding senior high school students to work on research projects at the university. The students began with extensive background reading on variable stars, and became familiar with various forms of time-series analysis. In the course of doing this, they prepared a useful manual for our publicly-available self-correlation analysis software (see below). They undertook an intensive analysis of the period changes in BC Cyg, using the (O-C) method, in the hope that evolutionary period changes could be observed. The (O-C) diagram, however, is dominated by the effects of random cycle-to-cycle period fluctuations. We will report on the results for this star, and a few others (T Cet, RW Cyg, S Per, W Per, XX Per, VX Sgr, CE Tau). We will also describe the Mentorship Program, and its elements, and reflect on the students' experience.

Acknowledgement: this project would not have been possible without the contributions of AAVSO visual observers over many decades.

Self-correlation software: http://www.astro.utoronto.ca/~percy/web/scs.zip
Manual: http://www.astro.utoronto.ca/~percy/manual

Mary Ann Kadooka 20 minutes
"Light and Optics Demonstrations for Astronomy"

How can you excite your audience about astronomy and telescopes when you have your star parties? What happens to the light coming from distant nebula or planet as it goes through the telescope to your eye? A basic physics review with demonstrations using mirrors and lenses will be used to answer this question. You will experience a discrepant phenomenon with an unexpected outcome. This creates a sense of wonder and the need for an explanation, motivating the person to learn more science. This is the goal of educational outreach, sharing a passion and wanting others to feel that same passion for astronomy.

Donna L Young 20 minutes
"Hands-On Astrophysics and Science Olympiad"

The Hands-On Astrophysics curriculum package is being converted to a web-based product in PDF format. Most of the student chapters have now been converted, with images substitutions and minor text revisions. It is anticipated that the entire student and teacher pages will be converted by spring. The pages will soon be placed on the AAVSO website so that AAVSO staff can enhance the materials with internal links and other materials. The membership is invited to view the status of the chapters and give input as to what should be done to improve Hands-On Astrophysics for amateur astronomers. Also, these materials as well as the AAVSO website are major resources for the National Science Olympiad high school astronomy event. There are other sites with Science Olympiad resources as well, and these will be shown to the membership so that if they are invited to assist Science Olympiad coaches with variable star astronomy, they will know where the resources are and how they can best meet the needs of the coaches.

Catherine Garland, Mary Ann Kadooka, Donn Starkey, and Michael Nassir 15 minutes
"HI STAR: Building Bridges Between AAVSO Observers and High School Students"

How did a Hawaiian high school student get to use a telescope in Indiana, via the internet, to observe celestial objects of her choosing? It was thanks to an AAVSO member who generously shared his telescope time. Donn Starkey not only shared his telescope and expertise with this student, but with 17 others this past summer at HI STAR, the Hawai`i Student Teacher Astronomy Research program hosted at the University of Hawai`i. This week-long "astronomy camp" for middle and high school students included lectures, activities, and--the highlight--observing. After just one week, all students, who had little to no background in astronomy, were able to begin astronomy research projects which they can continue at their schools. The content areas ranged from tracking asteroids, to doing photometry of variable stars, and calculating the rotational velocities of galaxies. We'll discuss highlights of the program, including how astronomers of all types can become involved with such promising students.