Graduate Student Savanah Turner Publishes Study of over 300 L and T dwarfs

BYU Astronomy Research Group Joins the Astrophysical Research Consortium (ARC)

As of January 2021 BYU will be a member of the ARC Consortium (Link to Consortium) with access to the ARC 3.5-m telescope and the 0.5-m ARCSAT telescope.  The primary use of the ARC 3.5-m telescope time is for graduate student projects.  This provides a wide array of instrumentation that is currently being used to study objects in the solar system all the way to studies of the large scale structure of the Universe.

Other BYU Astronomy Facilities

In addition to our telescope time from the ARC consortium, we operate a number of our own astronomical facilities

West Mountain Observatory (West Mountain)

This is our mountain observatory at about 6600 ft above sea level.  This consists of three telescopes: 0.9-m, 0.5-m, and a 0.32-m. It is a 40 minute drive that ends in a 5 miles drive up a dirt road. The mountain itself can be seen from campus. We don't provide any tours of this facility.

Orson Pratt Observatory

The Orson Pratt Observatory is named for an early apostle of the Church of Jesus Christ of Latter-Day Saints.  It is our campus telescope facility and contains a wide variety of telescopes for student research and public outreach. We operate a 24" PlaneWave telescope in the main campus dome, plus a 16", two 12", one 8", and a 6" telescope on our observation deck.  The telescopes are all fully robotic. Beyond this we have a large sections of telescopes used on public nights.

Royden G. Derrick Planetarium (Planetarium)

This is a 119 seat, 39" dome planetarium with acoustically treated walls to allow it's use as a lecture room. Recently we upgraded to an E&S Digistar7 operating system with 4K projectors.  The planetarium is used for teaching classes, public outreach, and astronomy education research projects.





Selected Publications

Photometric Abundance Calibration of δ Scuti Stars Using hk Photometry
The hk index has been used as a metallicity indicator for RR Lyrae variable stars. It is now being applied to the shorter period δ Scuti variables. Employing spectroscopic abundances of stars with published hk values and photometric indices calculated from stellar atmosphere models, a three-dimensional interpolation is used to determine [Fe/H] from intrinsic b-y, c1, and hk values. The resulting [Fe/H], log g, and Teff values for 10 δ Scuti stars are presented.
Interactive online archive for short-period variable stars
We report initial results from a project to design an interactive on-line data archive for short-period variable stars. Our goal is to provide an easily accessible set of web pages for use by a researcher at the telescope. The first step is to provide the researcher with convenient access to data archives for a variety of short-period variable stars. In addition to the basic data archive, there is a page for each star that contains positional information, the most recent epoch and period data, basic physical parameters, and a set of helpful journal references. We also include a page for each of the program variables with a finder chart and a selection of comparison stars for use in differential photometry. Additionally, one entry point in the system is a phase calculator that will sort through the data and return a list of stars that are observable from various user input locations during a variety of time periods. The current system has a partial data set in place for over one hundred short-period variable stars. We intend to continue to expand this set to include a large number of complete data files. We are also considering a similar archive of galaxy images for comparison use in student conducted supernova searches. We find this system improves the scientific return form our two small telescopes at the West Mountain Observatory. We believe this model can also be employed to optimize data management and scientific return for a wide variety of projects from the new generation of large ground-based telescopes.
Photometric studies of delta Scuti stars. II. V1162 Orionis
New photometric (uvby beta) observations of V1162 Orionis are reported. We derive a reddening value of E(b - y) = 0.021 mag and a metallicity of [Fe/H] = +0.1. Intrinsic (b - y) and c(1) values indicate a mean effective temperature, [T-eff] = 7540 K, and a mean surface gravity, [log g] = 3.96. Theoretical evolutionary tracks, along with pulsation models, indicate the mass of V1162 Ori is 1.8 M. and the age is 0.60 Gyr. New V magnitude CCD observations are also reported. A time of maximum light analysis shows that V1162 Ori has experienced a period break. In addition, the amplitude has dropped from Delta V = 0.2 before the period break to Delta V = 0.1 after the break.
Photometric studies of delta Scuti stars. I. IP Virginis
Michael D. Joner, Eric G. Hintz, and Matthew W. Collier
We report 15 new times of maximum light for the delta Scuti star IP Virginis (formerly known as SA 106-1024). An analysis of all times of maximum light indicates that IP Vir has been decreasing in period at a constant rate of -7.4 x 10(-9) days day(-1). Evidence is also presented that IP Vir is a double-mode variable with a period ratio of pi(1)/pi(0), = 0.774. This period ratio predicts a [Fe/H] value of -0.3. From photometric (uvby beta) observations, we find a foreground reddening of E(b - y) = 0.008 mag and a metallicity of [Fe/H] = +0.05. It is shown that [Fe/H] = -0.3 is most likely the correct value. Intrinsic (b - y)- and c(1)-values, plotted in a model atmosphere grid, indicate a mean effective temperature, [T-eff] = 7400 K, and a mean surface gravity, [log g] = 3.89. All of these physical parameters support Landolt's initial conclusion that IP Vir is an ordinary delta Sct star.
Multicolor, two-dimensional photometric study of galaxies in rich Abell clusters .1. Observations and reductions
We have embarked on a long term project to obtain high precision photometry on individual galaxies in 45 rich clusters of galaxies. Data from the first set of six clusters have yielded BVRI photometric information on 961 galaxies and 384 stars. These objects come from the central one Mpc of Abell 576, 957, 1185, 1377, 2063, and 2657, each of which is of richness class R greater than or equal to 1. Each object was examined with two radial surface brightness fitting functions, and an asymptotic magnitude was determined. One fitting function produced a shape parameter beta which, when taken in. combination with the color index (B-I), shows a breakdown of the three basic morphological types (E, S0, and S) into four beta types and a set of peculiar galaxies. Our results match previous studies well, and also provide some new insights into the clusters. In addition, we have examined the effects of plate scale on the determination of these photometric parameters. All parameters were found to repeat across plate scale differences. We also examined the effects of co-adding frames in an attempt to understand the degradation or improvement of the photometric parameters with increasing signal-to-noise. (C) 1997 American Astronomical Society.
Time-series ensemble photometry of SX Phoenicis stars .2. AE Ursae Majoris

We have examined the short-period, double-mode variable star AE Ursae Majoris. Using time-series ensemble photometry we have determined six new times of maximum light. We also applied a Fourier decomposition to the data to determine the component frequencies of the light curve. Using our data, along with archival data, we find that the period of AE UMa is continually decreasing at a rate of -1.14x10(-10) d d(-1). However, from the Fourier decomposition we find that the period ratio P-1/P-0 has remained constant at 0.773. We also find that AE UMa is incorrectly classified as a SX Phoenicis star.