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
New photometric (uvby beta) observations of the intrinsic variable star V798 Cyg have been secured and used to derive values of foreground reddening, E(b-y) = 0.117 mag, and metallicity, [Fe/H] = 0.64. Intrinsic (b-y) and c(1) values indicate a mean effective temperature, [T-eff] = 7150 K, and a mean surface gravity, [log g] = 3.39. Pulsation theory and theoretical evolutionary tracks yield a mass of 2.3 M. and an age of 0.63 Gyr. Although V798 Cyg has been described as being multiperiodic, this conclusion is not confirmed by our observations. V798 Cyg in most respects resembles a typical Population I dwarf Cepheid.
The three dwarf Cepheid variable stars CY Aquarii, XX Cygni, and V798 Cygni were examined with CCD time series ensemble photometry. The Fourier decomposition of the light curves showed no evidence that any of the three stars was a double-mode variable. CY Aqr was fit with a nine-term harmonic series with a residual error of 10 mmag. XX Cyg was fit with a ten-term harmonic series with a residual error of 10 mmag. V798 Cyg was fit with a four-term harmonic series with a residual error of 7 mmag. In addition, we examined a set of double-mode dwarf Cepheids with the same Fourier decomposition techniques. We present evidence that these double-mode dwarf Cepheids fill the gap in the amplitude-ratio distribution reported by Antonello et al. (1986, A&A, 169, 122) and Poretti et al. (1990, A&A, 228, 350).
We present an analysis of the multiperiodic SX Phoenicis star BL Camelopardalis (GD 428). Along with 24 times of maximum light from archival data, six previously unpublished times of maximum light from photomultiplier observations and 39 new CCD observations of maximum light are reported. The new CCD observations indicate that BL Cam is a double-mode variable with a primary period of 0.0391 day, a secondary period of 0.0306 day, and a pi(1)/pi(0) ratio of 0.783. The relation between metallicity and period ratio for large-amplitude delta Scuti variables is examined in detail. Finally, evidence is presented that the fundamental period pi(0) has increased by 0.009 s in the last 20 years.
Photometry of CY Aqr in the uvby beta and V(RI)(C) photometric systems has been secured and analyzed. A phase-averaged effective gravity of log g(eff)=4.04 and effective temperature of 7740 K are found from model-atmosphere grids. The star is metal poor with a derived [Fe/H]=-1.5. A mass of 1.06 M(.) is found from the analysis, the radius is 1.59 R(.), and absolute visual magnitude is M(V)=2.5.