Instrumentation Commons^™

Δ−Scuti Star Hr 1170, Salman A. Nejad

Aquila: The Journal of Embry-Riddle Observatory

HR 1170, a variable star in the constellation Perseus, exhibits multi-periodic pulsations consistent with its classification as a δ−Scuti star. Through photometric and spectroscopic observations using the 1-meter ERAU telescope and the SARA-RM telescope, this study investigates its variability and spectral characteristics. Photometry conducted over several nights reveals pulsation periods that closely align with previously reported values. Time-resolved spectroscopy highlights prominent absorption features, including Balmer lines and metallic elements, offering further insights into the star’s atmospheric dynamics.

Improving Photometry And Astrophotography By Eliminating Dark Frames And Flat Fields, Tom C. Ireland

Honors Theses and Capstones

I report on the efforts to improve the dark frames and flat fielding procedure for the charged-coupled device (CCD) camera for the Celestron C14 telescope at the UNH observatory. Dark frames are images taken while the shutter of the camera is closed so that only electronic and dark noise and other internal inconsistencies are recorded. These are important because they allow astronomers to subtract out interference from dark current. Additionally, flat fields are images of the entire field of the telescope so that the brightness in the pixels of the telescope’s field of view is uniform. Flat fields are vital …

Automation And Enhancements To The Erau Oscom System Space Situational Awareness, Sergei Bilardi, Patrick Rupp, Yevgeniy Lischuk, Joseph Stroup

Beyond: Undergraduate Research Journal

OSCOM, Optical tracking and Spectral characterization of CubeSats for Operational Missions, is a system developed at Embry-Riddle Aeronautical University to produce time-resolved photometry of small satellites using commercial-off-the-shelf hardware. OSCOM has been able to observe resident space objects (RSOs) as small as CubeSats using a Celestron 11” RASA and a CMOS machine vision camera from Allied Vision. By obtaining photometric measurements of satellites, a light curve can be constructed and used to help determine satellite characteristics such as spin rate, satellite state, and even satellite attitude. To enhance the OSCOM system’s ability to observe small satellites, there is ongoing development …

The Power Of Principled Bayesian Methods In The Study Of Stellar Evolution, Ted Von Hippel, David Van Dyk, David Stenning, Elliot Robinson, Elizabeth Jeffery, Nathan Stein, William Jefferys, Erin M. O'Malley

Publications

It takes years of effort employing the best telescopes and in- struments to obtain high-quality stellar photometry, astrometry, and spectroscopy. Stellar evolution models contain the experience of life- times of theoretical calculations and testing. Yet most astronomers fit these valuable models to these precious datasets by eye. We show that a principled Bayesian approach to fitting models to stellar data yields substantially more information over a range of stellar astrophysics. We highlight advances in determining the ages of star clusters, mass ratios of binary stars, limitations in the accuracy of stellar models, post-main-sequence mass loss, and the ages of individual …

Bayesian Analysis For Stellar Evolution With Nine Parameters (Base-9): User's Manual, Ted Von Hippel, Elliot Robinson, Elizabeth Jeffery, Rachel Wagner-Kaiser, Steven Degennaro, Nathan Stein, David Stenning, William H. Jefferys, David Van Dyk

Publications

BASE-9 is a Bayesian software suite that recovers star cluster and stellar parameters from photometry. BASE-9 is useful for analyzing single-age, single-metallicity star clusters, binaries, or single stars, and for simulating such systems. BASE-9 uses Markov chain Monte Carlo and brute-force numerical integration techniques to estimate the posterior probability distributions for the age, metallicity, helium abundance, distance modulus, and line-of-sight absorption for a cluster, and the mass, binary mass ratio, and cluster membership probability for every stellar object. BASE-9 is provided as open source code on a version-controlled web server. The executables are also available as Amazon Elastic Compute Cloud …

Maximizing Precision Of Variable Star Photometry With Digital Cameras In Suburban Environments, David Hergesheimer

STAR Program Research Presentations

Photometry is the measure of the brightness of an object. When making such measurements on stars, it is done is units of magnitude, which is on a logarithmic scale with a base of ~2.512. Variable star photometry using a commercially available digital camera is not going to be as accurate and precise as equipment used by astronomers, and because of the logarithmic scale of magnitude used, determining how much of an effect different error reduction strategies have is not straightforward, and is best done experimentally.

My research is conducting photometry on variable stars (changing brightness) with a digital camera, and …

Redshift-Distance Survey Of Early-Type Galaxies: Circular-Aperture Photometry, M. V. Alonso, M. Bernardi, L. N. Da Costa, G. Wegner

Dartmouth Scholarship

We present R -band CCD photometry for 1332 early-type galaxies, observed as part of the ENEAR survey of peculiar motions using early-type galaxies in the nearby universe. Circular apertures are used to trace the surface brightness profiles, which are then fitted by a two-component bulge-disk model. From the fits, we obtain the structural parameters required to estimate galaxy distances using the Dn - and fundamental plane relations. We find that about 12% of the galaxies are well represented by a pure r1/4 law, while 87% are best fitted by a two-component model. There are 356 repeated observations of 257 galaxies …