Emily Stoker and Pamela Lara discovered a close contact eclipsing binary system in observations taken with BYU's West Mountain Observatory. Using phased light curve data in several filters, Emily is using a modeling program called Phoebe to characterize the two stars and determine what fraction of the stars are in physical contact and how that effects the temperature of each object.
This solar eclipse image was secured on October 23, 2014 by Dr. Michael D. Joner. This observation was made at 4:05 PM MDT a couple of miles west of the BYU campus in Provo, Utah. In this near alignment of the Earth, Moon, and Sun only about 50% of the solar photosphere was blocked by the disk of the Moon as viewed from Provo. The result was a partial solar eclipse. The large group of sunspots near the center of the Sun has been cataloged as AR 2192. This is the largest active region seen during the current solar cycle. The dark central spot is significantly larger than the Earth. The entire sunspot complex is more than 100,000 km across.
This is a photo taken through light clouds during the early morning hours of October 8, 2014 showing a total eclipse of the full moon. This is the second of four total lunar eclipses that will be visible during the next two years around the time of the equinox. In a rare alignment, the faint star like object near the upper left edge of the image is actually the planet Uranus that has just reached opposition with the Sun. Photo credit: Dr. Michael D. Joner
The widely accepted intuition that the important properties of solids are determined by a few key variables underpins many methods in physics. Though this reductionist paradigm is applicable in many physical problems, its utility can be limited because the intuition for identifying the key variables often does not exist or is difficult to develop. We have developed a simple, general, and efficient way of finding the key descriptive variables using mathematics that has revolutionized image and signal processing. The key idea is to imagine physics as a "signal" provided by Mother Nature and to use compressive sensing (CS) to recover that signal. Compressive sensing is a powerful paradigm for model building; we find that its models are more physical and predict more accurately than current state-of-the-art approaches and can be constructed at a fraction of the computational cost and user effort.
Experimentally and computationally, the structure of Pt–Cu at 1:3 stoichiometry has a convoluted history. The L1_3 structure has been predicted to occur in binary alloy systems, but has not been linked to experimental observations. Using a combination of electron diffraction, synchrotron X-ray powder diffraction, and Monte Carlo simulations, we found that this phase is present in the Cu–Pt system at 1:3 stoichiometry. We also find that the 4-atom, fcc superstructure L13 is equivalent to the large 32-atom orthorhombic superstructure reported in older literature, resolving much of the confusion surrounding this composition. Monte Carlo simulations confirm the formation of a large cubic superstructure at high temperatures, and its eventual transformation to the L1_3 structure at lower temperature, but also provide evidence of other transitional orderings.
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Grayson Tarbox, Eric Cunningham, Ryan Sandberg, Justin Peatross, and Michael Ware recently published an article titled "Radiation from free electrons in a laser focus at 1018 W/cm2: modeling of photon yields and required focal conditions" in Journal of The Optical Society of America B: Optical Physics. Click on the image above to read it.
Nearby Spiral Galaxy NGC 4945: Large spiral galaxy NGC 4945 is seen edge-on near the center of this cosmic galaxy portrait. In fact, NGC 4945 is almost the size of our own Milky Way Galaxy. Its own dusty disk, young blue star clusters, and pink star forming regions standout in the sharp, colorful telescopic image....
This photograph and Description come from NASA's Astronomy Picture of the Day web site.