12 research outputs found
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Reflective Journaling: A Theoretical Model and Digital Prototype for Developing Resilience and Creativity
Reflection is commonly discussed as a tool for personal and professional development that is becoming increasingly important in today’s global and digital world. In this paper, we propose a model that suggests ways in which reflection, in the form of Reflective Journaling, can support the development of creativity and resilience, which are needed to enable individuals to function effectively in a fast-changing environment. In addition, the model proposes ways in which external support and progress monitoring can be used in conjunction with skills in adaptive resilience and structured creativity, to support the maintenance of reflective journaling as a habit, in the longer term, thus creating virtuous cycles of skills and behaviours that can reinforce each other. Based on our model, and additional user research, we describe the design of a first digital prototype that aims to support the use of Reflective Journaling and to develop creativity and resilience through suggested mechanisms. Initial evaluations of our prototype are positive. It has been well-received by early test users, and has the potential to address all the connections defined. We therefore suggest that the theoretical model can be used to develop digital tools, such as the one included, to help those who wish to develop the habit of reflective journaling, and through that a range of other skills associated with resilience and creative thinking. We see this as a starting point for investigating this potential in more depth
Star Clusters
This review concentrates almost entirely on globular star clusters. It
emphasises the increasing realisation that few of the traditional problems of
star cluster astronomy can be studied in isolation: the influence of the Galaxy
affects dynamical evolution deep in the core, and the spectrum of stellar
masses; in turn the evolution of the core determines the highest stellar
densities, and the rate of encounters. In this way external tidal effects
indirectly influence the formation and evolution of blue stragglers, binary
pulsars, X-ray sources, etc. More controversially, the stellar density appears
to influence the relative distribution of normal stars. In the opposite sense,
the evolution of individual stars governs much of the early dynamics of a
globular cluster, and the existence of large numbers of primordial binary stars
has changed important details of our picture of the dynamical evolution. New
computational tools which will become available in the next few years will help
dynamical theorists to address these questions.Comment: 10 pages, 3 figures, Te
Intrinsic Shapes of Elliptical Galaxies
Tests for the intrinsic shape of the luminosity distribution in elliptical
galaxies are discussed, with an emphasis on the uncertainties. Recent
determinations of the ellipticity frequency function imply a paucity of nearly
spherical galaxies, and may be inconsistent with the oblate hypothesis.
Statistical tests based on the correlation of surface brightness, isophotal
twisting, and minor axis rotation with ellipticity have so far not provided
strong evidence in favor of the nearly oblate or nearly prolate hypothesis, but
are at least qualitatively consistent with triaxiality. The possibility that
the observed deviations of elliptical galaxy isophotes form ellipses are due to
projection effects is evaluated. Dynamical instabilities may explain the
absence of elliptical galaxies flatter than about E6, and my also play a role
in the lack of nearly-spherical galaxies
Momentum transfer from the DART mission kinetic impact on asteroid dimorphos
The NASA Double Asteroid Redirection Test (DART) mission performed a kinetic impact on asteroid Dimorphos, the satellite of the binary asteroid (65803) Didymos, at 23:14 UTC on September 26, 2022 as a planetary defense test1. DART was the first hypervelocity impact experiment on an asteroid at size and velocity scales relevant to planetary defense, intended to validate kinetic impact as a means of asteroid deflection. Here we report the first determination of the momentum transferred to an asteroid by kinetic impact. Based on the change in the binary orbit period2, we find an instantaneous reduction in Dimorphos's along-track orbital velocity component of 2.70 ± 0.10 mm s-1, indicating enhanced momentum transfer due to recoil from ejecta streams produced by the impact3,4. For a Dimorphos bulk density range of 1,500 to 3,300 kg m-3, we find that the expected value of the momentum enhancement factor, [Formula: see text], ranges between 2.2 and 4.9, depending on the mass of Dimorphos. If Dimorphos and Didymos are assumed to have equal densities of 2,400 kg m-3, [Formula: see text]. These [Formula: see text] values indicate that significantly more momentum was transferred to Dimorphos from the escaping impact ejecta than was incident with DART. Therefore, the DART kinetic impact was highly effective in deflecting the asteroid Dimorphos