The goal of this study was to develop a self-report inventory that measures individual differences in the perceived value of mathematical literacy for general education students.The Mathematics Value Inventory (MVI) is grounded in the Eccles et al. model of achievement-related choices and surveys students’ beliefs in four areas: interest, general utility, need for high achievement, and personal cost. This study describes the development and initial score validation of the MVI. As hypothesized, it was found that (a) MVI scores for students who were not majoring in math did not differ by gender, (b) students who had higher MVI scores had completed more college course work in math than did students with lower scores, and (c) MVI scores were not related to scores on a measure of social desirability.

We discuss an approximate analytical model for the hydrodynamic evolution of the shock front produced by a spherically symmetric explosion in a homogeneous medium. The model assumes a particular relation between the energy of the explosion, the density of the medium into which the shock wave is expanding, and the particle speed immediately behind the shock front. The assumed relation is exact for shock waves that are strong and self‐similar. Comparison with numerical simulations indicates that the relation is also approximately valid for shock waves that are neither strong nor self‐similar. Using the assumed relation and the Hugoniot of the ambient medium expressed as a relation between the shock speed and the postshock particle speed, one can calculate the radius and other properties of the shock front as a function of time. The model also allows one to investigate how the evolution of the shock wave is influenced by the properties of the ambient medium and how these properties affect the characteristic radius at which the shock wave becomes a low‐pressure plastic wave. The shock front radius versus time curves predicted by the model agree well with numerical simulations of explosions in quartz and wet tuff and with data from four underground nuclear tests conducted in granite, basalt, and wet tuff when the official yields are assumed. When the model is used instead to fit radius versus time data from the hydrodynamic phases of these tests, it gives yields that are within 8% of the official yields when piecewise‐linear approximations to the Hugoniots are used. This accuracy is comparable to the accuracy of other models.

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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−1 across 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.

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