CCD UBVRi photometry of the final helium flash object V4334 Sgr (Sakurai's Object), carried out during 1997 -1999, is presented, and the light curve from its pre-discovery rise to the dust obscuration phase is constructed. The optical light curve can be divided into four sections, the rise to maximum, the maximum, the dust onset, and the massive dust shell phase. The color indices show a general increase with time, first because of the photospheric expansion and cooling, and later because of the dust forming events. The energy distributions for the years 1996 -1999 show that an increasing part of the energy is radiated at infrared wavelengths. In 1996, the infrared excess is likely caused by free-free radiation in the stellar wind. Starting from 1997 or 1998 at the latest, carbon dust grains are responsible for the more and more dramatic decrease of optical radiation and the growing infrared excess. Its photometric behavior in 1998 -1999 mimics the "red declines" of R CrB variables, the amplitude, however, is more extreme than any fading ever observed in an R CrB star. Evidence is given that a complete dust shell has formed around V4334 Sgr. It therefore shows similarities with dust-forming classical novae, although evolving ∼ 20 times more slowly. Its luminosity increased by a factor 4 between 1996 and 1998. A comparison of time scales of the final helium flash objects FG Sge, V605 Aql and V4334 Sgr shows that the observed photometric and spectroscopic features are similar, while V4334 Sgr is the most rapidly evolving object to date. ObservationsUBVRi observations of V4334 Sgr were carried out with the 0.91 m Dutch light collector at ESO La Silla, until its shutdown on April 1, 1999. Filters and comparison stars were the same as those used in D97 (the filters R and i refer to Cousins R C and Gunn i G , respectively). The object was also observed until 1998 October with the 0.2 m f /1.5 Schmidt telescope of W. Liller in Reñaca, Viña del Mar, Chile. Additional observations were obtained with the 3.5 m Telescopio Nazionale Galileo (TNG) 6 in July, 1999.The early observations with the Dutch telescope were analyzed using ROMAFOT aperture photometry. The continuing decline in brightness, especially at short wavelengths, made it necessary to carry out DAOPHOT profile fitting photometry of V4334 Sgr from 1997 September 15 onward. Because of the increase of exposure times, comparison star (1) of D97 became too bright to be used as a local standard, and the average magnitude of stars (2) − (6) (taken from D97) was used as the reference magnitude in all filters. The Reñaca observations are based on CCD aperture photometry. Since they were always taken relative to star (1) through a non-standard V filter which extends towards the red, a transformation was established from simultaneous Dutch (V, i) and Reñaca (∆V ⋆ ) observations, which permits to convert the Reñaca observations into the standard V system:where ∆V ⋆ is the magnitude difference relative to the bright comparison star; the color V − i is taken from the "Dutch" ...

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Seventy undergraduate class sections were examined from the database of Astronomy Diagnostic Test (ADT) results of Deming and Hufnagel to determine if course format correlated with ADT normalized gain scores. Normalized gains were calculated for four different classroom scenarios: lecture, lecture with discussion, lecture with lab, and lecture with both lab and discussion. Statistical analysis shows that there are no significant differences in normalized gain among the self-reported classroom formats. Prerequisites related to mathematics courses did show differences in normalized gain. Of all reported course activities, only the lecture and the readings for the course correlate significantly with the normalized gain. This analysis suggests that the ADT may not have enough sensitivity to measure differences in the effectiveness of different course formats because of the wide range of topics that the ADT addresses with few questions. Different measures of gain and their biases are discussed. We argue that the use of the normalized gain is not always warranted because of its strong bias toward high pretest scores.

Field work is an integral component of undergraduate geoscience education. Field areas for these crucial experiences are carefully selected, but how do these places affect our students? This study compares the field experience of students participating in two distinct modules of a study abroad field camp in New Zealand, through sense of place and perceptions of learning. The situated module was geological mapping based in a single site, whereas the roadside module was based on smaller exercises in multiple discrete sites. Survey findings indicate that students became significantly more attached to the situated field area, but had no significant change in their attachment to the roadside field area. Field observations and interview findings suggest that this may be due to student autonomy, the immersive landscape, and strong alignment of student perceptions of learning with instructor intentions on the situated field module. In contrast, the roadside module was more determined by the instructor, and student perceptions of learning did not align well with instructor intent in conveying a sense of the regional geologic history. We assimilate our field observations and student and instructor interview data into a schematic model of the two field trip styles. This model is then used to visualize an improved pedagogy to foster greater engagement with the landscape and geology in the roadside trip. We recommend that roadside field trips have explicit assessments that connect the field sites together. Our interview data suggest that this connection would be further enhanced with greater opportunities for student ownership of in-field decision making through student-centered learning, encouragement of a sense of exploration, and development of a student and instructor field learning community. RESEARCH CONTEXT Field Education: Benefits and StylesField trips are widely used in geoscience education around the globe and in several other disciplines, including geography (e.g., Gold et al

The 'holy grail' in planet hunting is the detection of an Earth-analogue: a planet with similar mass as the Earth and an orbit inside the habitable zone. If we can find such an Earth-analogue around one of the stars in the immediate solar neighbourhood, we could potentially even study it in such great detail to address the question of its potential habitability. Several groups have focused their planet detection efforts on the nearest stars. Our team is currently performing an intensive observing campaign on the α Centauri system using the High Efficiency and Resolution Canterbury University Large Échelle Spectrograph (HERCULES) at the 1 m McLellan telescope at Mt John University Observatory in New Zealand. The goal of our project is to obtain such a large number of radial velocity (RV) measurements with sufficiently high temporal sampling to become sensitive to signals of Earth-mass planets in the habitable zones of the two stars in this binary system. Over the past few years, we have collected more than 45 000 spectra for both stars combined. These data are currently processed by an advanced version of our RV reduction pipeline, which eliminates the effect of spectral cross-contamination. Here we present simulations of the expected detection sensitivity to low-mass planets in the habitable zone by the HERCULES programme for various noise levels. We also discuss our expected sensitivity to the purported Earth-mass planet in a 3.24-day orbit announced by Dumusque et al. (2012).

Abstract.A new method, AMORE -based on a genetic algorithm optimizer, is presented for the automated study of colourmagnitude diagrams. The method combines several stellar population synthesis tools developed in the last decade by or in collaboration with the Padova group. Our method is able to recover, within the uncertainties, the parameters -distance, extinction, age, metallicity, index of a power-law initial mass function and the index of an exponential star formation rate -from a reference synthetic stellar population. No a priori information is inserted to recover the parameters, which is done simultaneously and not one at a time. Examples are given to demonstrate and to better understand biases in the results, if one of the input parameters is deliberately set fixed to a non-optimum value.

We present an interactive, immersive, authentic role-play simulation designed to teach tertiary geoscience students in New Zealand to forecast and mitigate a volcanic crisis. Half of the participating group (i.e., the Geoscience Team) focuses on interpreting real volcano monitoring data (e.g., seismographs, gas output etc.) while the other half of the group (i.e., the Emergency Management Team) forecasts and manages likely impacts, and communicates emergency response decisions and advice to local communities. These authentic learning experiences were aimed at enhancing upper-year undergraduate students' transferable and geologic reasoning skills. An important goal of the simulation was specifically to improve students' science communication through interdisciplinary team discussions, jointly prepared, and delivered media releases, and real-time, high-pressure, press conferences. By playing roles, students experienced the specific responsibilities of a professional within authentic organisational structures. A qualitative, design-based educational research study was carried out to assess the overall student experience and self-reported learning of skills. A pilot and four subsequent iterations were investigated. Results from this study indicate that students found these role-plays to be a highly challenging and engaging learning experience and reported improved skills. Data from classroom observations and interviews indicate that the students valued the authenticity and challenging nature of the role-play although personal experiences and team dynamics (within, and between the teams) varied depending on the students' background, preparedness, and personality. During early iterations, observation and interviews from students and instructors indicate that some of the goals of the simulation were not fully achieved due to: A) lack of preparedness, B) insufficient time to respond appropriately, C) appropriateness of roles and team structure, and D) poor communication skills. Small modifications to the design of Iterations 3 and 4 showed an overall improvement in the students' skills and goals being reached. A communication skills instrument (SPCC) was used to measure self-reported pre-and post-communication competence in the last two iterations. Results showed that this instrument recorded positive shifts in all categories of self-perceived abilities, the largest shifts seen in students who participated in press conferences. Future research will be aimed at adapting this curricula to new volcanic and earthquake scenarios.