NASA Earth and Space Science Explorers Poster

This poster features several of the NASA Earth and Space Science Explorers, plus suggestions for using the series in the classroom. The series of online articles features NASA explorers, young and old, with many backgrounds and interests. Most articles are written for three different reading levels: grades K-4, grades 5-8, and grades 9-12 and up. Educational levels: Primary elementary, Middle school, High school

Reactive explorers to unravel network topology

A procedure is developed and tested to recover the distribution of connectivity of an a priori unknown network, by sampling the dynamics of an ensemble made of reactive walkers. The relative weight between reaction and relocation is gauged by a scalar control parameter, which can be adjusted at will. Different equilibria are attained by the system, following the externally imposed modulation, and reflecting the interplay between reaction and diffusion terms. The information gathered on the observation node is used to predict the stationary density as displayed by the system, via a direct implementation of the celebrated Heterogeneous Mean Field (HMF) approximation. This knowledge translates into a linear problem which can be solved to return the entries of the sought distribution. A variant of the model is then considered which consists in assuming a localized source where the reactive constituents are injected, at a rate that can be adjusted as a stepwise function of time. The linear problem obtained when operating in this setting allows one to recover a fair estimate of the underlying system size. Numerical experiments are carried so as to challenge the predictive ability of the theory

Exploring Planets with Directed Aerial Robot Explorers

Global Aerospace Corporation (GAC) is developing a revolutionary system architecture for exploration of planetary atmospheres and surfaces from atmospheric altitudes. The work is supported by the NASA Institute for Advanced Concepts (NIAC). The innovative system architecture relies upon the use of Directed Aerial Robot Explorers (DAREs), which essentially are long-duration-flight autonomous balloons with trajectory control capabilities that can deploy swarms of miniature probes over multiple target areas. Balloon guidance capabilities will offer unprecedented opportunities in high-resolution, targeted observations of both atmospheric and surface phenomena. Multifunctional microprobes will be deployed from the balloons once over the target areas, and perform a multitude of functions, such as atmospheric profiling or surface exploration, relaying data back to the balloons or an orbiter. This architecture will enable low-cost, low-energy, long-term global exploration of planetary atmospheres and surfaces. This paper focuses on a conceptual analysis of the DARE architecture capabilities and science applications for Venus, Titan and Jupiter. Preliminary simulations with simplified atmospheric models show that a relatively small trajectory control wing can enable global coverage of the atmospheres of Venus and Titan by a single balloon over a 100-day mission. This presents unique opportunities for global in situ sampling of the atmospheric composition and dynamics, atmospheric profiling over multiple sites with small dropsondes and targeted deployment of surface microprobes. At Jupiter, path guidance capabilities of the DARE platforms permits targeting localized regions of interest, such as "hot spots" or the Great Red Spot. A single DARE platform at Jupiter can sample major types of the atmospheric flows (zones and belts) over a 100-day mission. Observations by deployable probes would reveal if the differences exist in radiative, dynamic and compositional environments at these sites

'Beautiful beasts' and brave warriors: the longevity of a Maasai stereotype

This chapter (in the fourth edition of a widely respected anthropological textbook) traces the production by imperial explorers and others of a stereotypical image of the Maasai people of Kenya, the continuities to the present day, and the uses to which this stereotype has been put

Putting Antarctica on the Map

This six-day unit has students examine historical maps of Antarctica and research early explorers to gain perspective on how cartography and our understanding of the globe have changed. The curriculum materials contain teacher tools including individually downloadable readings, detailed daily breakdowns of tasks, teacher strategies for using the activities, a portfolio grading sheet, a project rubric sheet, and supplemental readings. In addition, a Web activity in which students examine and compare historical maps and their modern-day equivalents, highlights how map-making techniques have changed. A classroom activity in which students examine the history of Antarctic exploration and conduct research on a topic of interest and several readings that provide a broad perspective, including excerpts from early explorers' journals and an interview with a marine biologist who studies the history of Antarctica, round out the unit. A student handout provides guidance for putting together student portfolios and examples of creative final projects. Educational levels: High school, Middle school

Line-Recovery by Programmable Particles

Shape formation has been recently studied in distributed systems of programmable particles. In this paper we consider the shape recovery problem of restoring the shape when $f$ of the $n$ particles have crashed. We focus on the basic line shape, used as a tool for the construction of more complex configurations. We present a solution to the line recovery problem by the non-faulty anonymous particles; the solution works regardless of the initial distribution and number $f<n-4$ of faults, of the local orientations of the non-faulty entities, and of the number of non-faulty entities activated in each round (i.e., semi-synchronous adversarial scheduler)

CAHRS Partners\u27 Implementation of Artificial Intelligence

[Excerpt] The ideas and uses for Artificial Intelligence (AI) are abundant, and each business is seemingly ripe for disruption, including HR. As the hype surrounding AI continues to be championed by popular press, we began our research in order to determine whether the press’ biased view that AI was here and ready to implement was accurate. We found that in reality, AI programs were far behind the progress discussed, as the software was slower, more expensive, and there was a general lack of amalgamation throughout the industry. From there, we asked CAHRS partners to tell us where AI was used in their company, and how it helped them deliver HR differently. Our research focused on how AI technology will disrupt, change, or bolster the HR function, specifically in Talent Acquisition and Learning and Development (L&D) spaces. We found our CAHRS partners dove into AI, and represented three key points along a spectrum of AI implementation. Of the 59 participants at 32 companies, 26% are Observers, 48% are Explorers, and 26% are Implementers. Observers were companies that did not believe AI fits with their strategy, and therefore do not intend to implement AI right now. Explorers are companies that have begun to actively explore AI through industry research, vendor exploration, and piloting AI and machine learning (ML) technologies. Implementers are companies that have either built in house or worked with an external vendor to implement an AI or machine learning technology. The CAHRS partners represented such a wide range along this spectrum because there are no best practices for AI implementation. However, each of our partners that leveraged AI understood the tool, while also understanding their business needs, people, and technology, which allowed them to utilize AI technology

Sublogarithmic fluctuations for internal DLA

We consider internal diffusion limited aggregation in dimension larger than or equal to two. This is a random cluster growth model, where random walks start at the origin of the d-dimensional lattice, one at a time, and stop moving when reaching a site that is not occupied by previous walks. It is known that the asymptotic shape of the cluster is a sphere. When the dimension is two or more, we have shown in a previous paper that the inner (resp., outer) fluctuations of its radius is at most of order $\log(\mathrm{radius})$ [resp., $\log^2(\mathrm{radius})$]. Using the same approach, we improve the upper bound on the inner fluctuation to $\sqrt{\log(\mathrm{radius})}$ when d is larger than or equal to three. The inner fluctuation is then used to obtain a similar upper bound on the outer fluctuation.Comment: Published in at http://dx.doi.org/10.1214/11-AOP735 the Annals of Probability (http://www.imstat.org/aop/) by the Institute of Mathematical Statistics (http://www.imstat.org

Novelty Induces Behavioural And Glucocorticoid Responses In A Songbird Artificially Selected For Divergent Personalities

Stress physiology is thought to contribute to individual differences in behaviour. In part this reflects the fact that canonical personality measures consist of responses to challenges, including novel objects and environments. Exposure to novelty is typically assumed to induce a moderate increase in glucocorticoids (CORT), although this has rarely been tested. We tested this assumption using great tits, Parus major, selected for divergent personalities (bold-fast and shy-slow explorers), predicting that the shy birds would exhibit higher CORT following exposure to a novel object. We also scored behavioural responses to the novel object, predicting that bold birds would more frequently approach the novel object and exhibit more abnormal repetitive behaviours. We found that the presence of a novel object did induce a moderate CORT response, but selection lines did not differ in the magnitude of this response. Furthermore, although both selection lines showed a robust CORT elevation to a subsequent restraint stressor, the CORT response was stronger in bold birds and this effect was specific to novel object exposure. Shy birds showed a strong positive phenotypic correlation between CORT concentrations following the novel object exposure and the subsequent restraint stress. Behaviourally, the selection lines differed in their response during novel object exposure: as predicted, bold birds more frequently approached the novel object and shy birds more strongly decreased overall locomotion during the novel object trial, but birds from both selection lines showed significant and similar frequencies of abnormal repetitive behaviours during novel object exposure. Our findings support the hypothesis that personality emerges as a result of correlated selection on behaviour and underlying endocrine mechanisms and suggest that the relationship between endocrine stress physiology and personality is context dependent