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Many of us find women's football more exciting to watch than the men's game. But why? A statistical analysis by Matthew J. Penn and Joanna Marks provides some answers [ABSTRACT FROM AUTHOR]

The Advanced Technology Solar Telescope (ATST) will be a 4 m aperture off-axis telescope with advanced high-resolution and low scattered light capabilities for the observation of the solar photosphere and corona. The site characteristics that are critical to the success of the ATST coronal observations are the sky brightness, the precipitable water vapor content, and the number and size distributions of the dust particles. Therefore, part of the ATST site survey effort is to obtain measurements of these atmospheric properties at all the potential ATST sites. The ATST site survey Sky Brightness Monitor (SBM) is a new instrument specifically developed for this task. The SBM is a modified externally occulted coronagraph capable of imaging the solar disk and sky simultaneously. The ability to image the Sun and the sky simultaneously greatly simplifies the calibration of the sky-brightness measurements. The SBM has a very simple optical configuration that makes it a compact and low-maintenance instrument. The SBM is sensitive to sky brightness below 1 × 10-6disk center intensity, with a field of view extending from 4 to 8 R?. It measures the solar disk and sky brightness at three continuum bandpasses located at 450, 530, and 890 nm. A fourth bandpass is centered at the 940 nm water vapor absorption band. With measurements of disk and sky brightness at these four wavelengths, site characteristics such as extinctions, aerosol content, and precipitable water vapor content can be derived. This paper documents the design, specifications, calibration procedures, and performance of the SBM.

The Mees CCD (MCCD) instrument is an imaging spectroscopy device which uses the 25 cm coronagraph telescope and the 3.0 m Coudé spectrograph at Mees Solar Observatory (MSO) on Haleakala, Maui. The instrument works with resolving power up to R ˜ 200 000 with significant throughput from ?3934 Å (Caii K) to ? ˜ 10 000 Å. A fast guiding active mirror stabilizes the image during observations. A rapidly writing magnetic tape storage system allows observations to be recorded at 256 kbytes s-1. Currently, the MCCD is used for imaging spectroscopy of solar flares at ?6563 Å (Ha), and velocity measurements of umbral oscillations; future plans include emission line studies of active region coronae, and photospheric studies of solar oscillations.

The citizen Continental-America Telescopic Eclipse (CATE) Experiment was a new type of citizen science experiment designed to capture a time sequence of white-light coronal observations during totality from 17:16 to 18:48 UT on 2017 August 21. Using identical instruments the CATE group imaged the inner corona from 1 to 2.1 RSun with 1.?43 pixels at a cadence of 2.1 s. A slow coronal mass ejection (CME) started on the SW limb of the Sun before the total eclipse began. An analysis of CATE data from 17:22 to 17:39 UT maps the spatial distribution of coronal flow velocities from about 1.2 to 2.1 RSun, and shows the CME material accelerates from about 0 to 200 km s?1across this part of the corona. This CME is observed by LASCO C2 at 3.1-13 RSun with a constant speed of 254 km s?1. The CATE and LASCO observations are not fit by either constant acceleration nor spatially uniform velocity change, and so the CME acceleration mechanism must produce variable acceleration in this region of the corona.

The infrared solar spectrum contains a wealth of physical data about our Sun, and is explored using modern detectors and technology with new ground-based solar telescopes. The scientific motivation behind exploring these wavelengths is presented, along with a brief look at the rich history of observations here. Several avenues of solar physics research exploiting and benefiting from observations at infrared wavelengths from roughly 1000 nm to 12 400 nm are discussed, and the instrument and detector technology driving this research is briefly summarized. Finally, goals for future work at infrared wavelengths are presented in conjunction with ground and space-based observations.

Many types of velocity oscillations are observed in the umbrae and penumbrae of sunspots. We describe a project aimed at determining the source of one type of oscillation, the five-minute period photospheric umbra oscillations. The project uses imaging spectroscopy of spot umbrae, measuring the Doppler shift of pure umbral absorption lines to study the temporal and spatial properties of these oscillations. The Mees CCD (MCCD) instrument is an imaging spectroscopy device which uses the 25-cm coronagraph telescope and the 3.0-m coude spectrograph at Mees Solar Observatory (MSO) on Haleakala, Maui. The instrument works with resolving power up to R ~ 200,000 with significant throughput from lambda-3934 A (Ca II K) to lambda ~ 10,000 A. A fast guiding active mirror stabilizes the image during observations. A rapidly writing magnetic tape storage system allows observations to be recorded at 256 kbytes s-1. We observed the oscillations in the umbrae of two sunspots using the MCCD imaging spectrograph. We observed the Doppler shifts of 18 molecular lines in the umbrae for roughly 50 hours in each spot during the interval of 11 to 16 May 1991. We find no simple correlation between the velocity measured with molecular lines and the velocity measured using two iron lines. We remove solar rotation, image drift, and interpolate all the data onto an even time grid. We perform four spatial analyses of the umbral velocity and find (1) there is more power traveling toward the center of the umbrae than leaving the center of the umbrae (this provides a direct measure of the absorption of p-modes by the sunspot umbrae) (2) the umbral oscillations have spatial and temporal characteristics indistinguishable from the quiet-sun oscillations, (3) a Fourier-Bessel analysis shows no obvious resonant frequencies which might represent natural oscillation modes of the sunspot umbrae, and (4) the centers of the umbrae have less RMS velocity than the edge of the umbrae. >From these analyses we conclude that the photospheric umbral oscillations are driven by an external source and that source is the global p-mode oscillations.