Astrophysics datamining in the classroom: Exploring real data with new software tools and robotic telescopes

Within the efforts to bring frontline interactive astrophysics and astronomy to the classroom, the Hands on Universe (HOU) developed a set of exercises and platform using real data obtained by some of the most advanced ground and space observatories. The backbone of this endeavour is a new free software Web tool - Such a Lovely Software for Astronomy based on Image J (Salsa J). It is student-friendly and developed specifically for the HOU project and targets middle and high schools. It allows students to display, analyze, and explore professionally obtained astronomical images, while learning concepts on gravitational dynamics, kinematics, nuclear fusion, electromagnetism. The continuous evolving set of exercises and tutorials is being completed with real (professionally obtained) data to download and detailed tutorials. The flexibility of the Salsa J platform tool enables students and teachers to extend the exercises with their own observations. The software developed for the HOU program has been designed to be a multi-platform, multi-lingual experience for image manipulation and analysis in the classroom. Its design enables easy implementation of new facilities (extensions and plugins), minimal in-situ maintenance and flexibility for exercise plugin. Here, we describe some of the most advanced exercises about astrophysics in the classroom, addressing particular examples on gravitational dynamics, concepts currently introduced in most sciences curricula in middle and high schools.Comment: 10 pages, 12 images, submitted to the special theme issue Using Astronomy and Space Science Research in Physics Courses of the American Journal of Physic

Photometry of Variable Stars from Dome A, Antarctica

Dome A on the Antarctic plateau is likely one of the best observing sites on Earth thanks to the excellent atmospheric conditions present at the site during the long polar winter night. We present high-cadence time-series aperture photometry of 10,000 stars with i<14.5 mag located in a 23 square-degree region centered on the south celestial pole. The photometry was obtained with one of the CSTAR telescopes during 128 days of the 2008 Antarctic winter. We used this photometric data set to derive site statistics for Dome A and to search for variable stars. Thanks to the nearly-uninterrupted synoptic coverage, we find 6 times as many variables as previous surveys with similar magnitude limits. We detected 157 variable stars, of which 55% are unclassified, 27% are likely binaries and 17% are likely pulsating stars. The latter category includes delta Scuti, gamma Doradus and RR Lyrae variables. One variable may be a transiting exoplanet.Comment: Accepted for publication in the Astronomical Journal. PDF version with high-resolution figures available at http://faculty.physics.tamu.edu/lmacri/papers/wang11.pd

PHOTOMETRY OF VARIABLE STARS FROM DOME A, ANTARCTICA: RESULTS FROM THE 2010 OBSERVING SEASON

We present results from a season of observations with the Chinese Small Telescope ARray (CSTAR), obtained over 183 days of the 2010 Antarctic winter. We carried out high-cadence time-series aperture photometry of 20,000 stars with i<15.3 mag located in a 23 square-degree region centered on the south celestial pole. We identified 188 variable stars, including 67 new objects relative to our 2008 observations, thanks to broader synoptic coverage, a deeper magnitude limit and a larger field of view. We used the photometric data set to derive site statistics from Dome A. Based on two years of observations, we find that extinction due to clouds at this site is less than 0.1 and 0.4 mag during 45% and 75% of the dark time, respectively.Comment: Accepted for publication in the Astronomical Journal. Light curves and finding charts of all variable stars will be made available at http://casdc.china-vo.org/data/csta

STELLAR VARIABILITY AND FLARE RATES FROM DOME A, ANTARCTICA, USING 2009 AND 2010 CSTAR OBSERVATIONS

The Chinese Small Telescope ARray (CSTAR) carried out high-cadence time-series observations of 20.1 square degrees centered on the South Celestial Pole during the 2008, 2009 & 2010 winter seasons from Dome A in Antarctica. The nearly-continuous 6 months of dark conditions during each observing season allowed for >10^6 images to be collected through gri and clear filters, resulting in the detection of >10^4 sources over the course of 3 years of operation. The nearly space-like conditions in the Antarctic plateau are an ideal testbed for the suitability of very small-aperture (<20 cm) telescopes to detect transient events, variable stars and stellar flares. We present the results of a robust search for such objects using difference image analysis of the data obtained during the 2009 & 2010 winter seasons. While no transients were found, we detected 29 flaring events and find a normalized flaring rate of 5+\-4x10^-7 flare/hour for late-K dwarfs, 1+\-1x10^-6 flare/hour for M dwarfs and 7+\-1x10^-7 flare/hour for all other stars in our sample. We suggest future small-aperture telescopes planned for deployment at Dome A would benefit from a tracking mechanism, to help alleviate effects from ghosting, and a finer pixel scale, to increase the telescope's sensitivity to faint objects. We find that the light curves of non-transient sources have excellent photometric qualities once corrected for systematics, and are limited only by photon noise and atmospheric scintillation.Comment: Accepted for Publication in the Astronomical Journal, 14 pages, 12 figures and 2 table