No Arabic abstract
In an age of media saturation, how can astronomers succeed in grabbing the publics attention to increase awareness and understanding of astronomy? Here I discuss some creative alternatives to press releases, public lectures, television programs, books, magazine articles, and other traditional ways of bringing astronomy to a wide audience. By thinking outside the box and employing novel tools - from truly terrible sci-fi movies, to modern Stonehenges, to music from the stars - astronomers are finding effective new ways of communicating the wonders of the universe to people of all ages.
In this work we address the problem of estimating the probabilities of causal contacts between civilisations in the Galaxy. We make no assumptions regarding the origin and evolution of intelligent life. We simply assume a network of causally connected nodes. These nodes refer somehow to intelligent agents with the capacity of receiving and emitting electromagnetic signals. Here we present a three-parametric statistical Monte Carlo model of the network in a simplified sketch of the Galaxy. Our goal, using Monte Carlo simulations, is to explore the parameter space and analyse the probabilities of causal contacts. We find that the odds to make a contact over decades of monitoring are low for most models, except for those of a galaxy densely populated with long-standing civilisations. We also find that the probability of causal contacts increases with the lifetime of civilisations more significantly than with the number of active civilisations. We show that the maximum probability of making a contact occurs when a civilisation discovers the required communication technology.
Some 400 years after Galileo, modern telescopes have enabled humanity to see what the natural eye cannot. Astronomical images today contain information about incredibly large objects located across vast distances and reveal information found in invisible radiation ranging from radio waves to X-rays. The current generation of telescopes has created an explosion of images available for the public to explore. This has, importantly, coincided with the maturation of the Internet. Every major telescope has a web site, often with an extensive gallery of images. New and free downloadable tools exist for members of the public to explore astronomical data and even create their own images. In short, a new era of an accessible universe has been entered, in which the public can participate and explore like never before. But there is a severe lack of scholarly and robust studies to probe how people - especially non-experts - perceive these images and the information they attempt to convey. Most astronomical images for the public have been processed (e.g., color choices, artifact removal, smoothing, cropping/field-of-view shown) to strike a balance between the science being highlighted and the aesthetics designed to engage the public. However, the extent to which these choices affect perception and comprehension is, at best, poorly understood. The goal of the studies presented here was to begin a program of research to better understand how people perceive astronomical images, and how such images, and the explanatory material that accompanies them, can best be presented to the public in terms of understanding, appreciation, and enjoyment of the images and the science that underlies them.
This article was written at the invitation of Current Science to explain the history and Science behind this years Nobel prize in Physics. The article is aimed at a general audience and provides a popular account and perspective on the subject of black holes.
The nascent field of gravitational-wave astronomy offers many opportunities for effective and inspirational astronomy outreach. Gravitational waves, the ripples in space-time predicted by Einsteins theory of General Relativity, are produced by some of the most energetic and dramatic phenomena in the cosmos, including black holes, neutron stars and supernovae. The detection of gravitational waves will help to address a number of fundamental questions in physics, from the evolution of stars and galaxies to the origin of dark energy and the nature of space-time itself. Moreover, the cutting-edge technology developed to search for gravitational waves is pushing back the frontiers of many fields, from lasers and materials science to high performance computing, and thus provides a powerful showcase for the attractions and challenges of a career in science and engineering. For several years a worldwide network of ground-based laser interferometric gravitational-wave detectors has been fully operational, including the two LIGO detectors in the United States. These detectors are already among the most sensitive scientific instruments on the planet and in the next few years their sensitivity will achieve further significant improvement. Those developments promise to open an exciting new window on the Universe, heralding the arrival of gravitational-wave astronomy as a revolutionary, new observational field. In this paper we describe the extensive program of public outreach activities already undertaken by the LIGO Scientific Collaboration, and a number of special events which we are planning for IYA2009.
In the pattern formation problem, robots in a system must self-coordinate to form a given pattern, regardless of translation, rotation, uniform-scaling, and/or reflection. In other words, a valid final configuration of the system is a formation that is textit{similar} to the desired pattern. While there has been no shortage of research in the pattern formation problem under a variety of assumptions, models, and contexts, we consider the additional constraint that the maximum distance traveled among all robots in the system is minimum. Existing work in pattern formation and closely related problems are typically application-specific or not concerned with optimality (but rather feasibility). We show the necessary conditions any optimal solution must satisfy and present a solution for systems of three robots. Our work also led to an interesting result that has applications beyond pattern formation. Namely, a metric for comparing two triangles where a distance of $0$ indicates the triangles are similar, and $1$ indicates they are emph{fully dissimilar}.