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We report an imaging capability of the Japan-led X-ray observatory Hitomi, formerly known as ASTRO-H. It carries four scientific instruments of Soft X-ray Imager (SXI: CCD camera), Hard X-ray Imager (HXI), Soft X-ray Spectrometer, and Soft Gamma-ray Detector, allowing us to perform a wide-band high-sensitive imaging spectroscopy. We highlight the specification and the performance we obtained with primarily regard to X-ray and soft gamma-ray imaging. Primary imaging instrument SXI utilizes four large-area X-ray CCDs positioned at the focal plane of Soft X-ray Telescope (SXT-I). Imaging area with a size of 62 mm square makes a largest field of view (FoV) of 38′ square among the focal plane X-ray detectors, which enables us to observe extended objects such as clusters of galaxies and galactic supernova remnants with a single pointing in the soft X-ray band from 0.4 to 12 keV. HXI employs the hybrid sensors consisting of four layers of double-sided silicon strip detectors and a single layer of cadmium telluride double-sided strip detector covering the energy band from 5 to 80 keV. After the successful launch of Hitomi on February 17th, 2016 and the subsequent start up of all the instruments, imaging performance of both imagers are verified as expected from the ground calibration tests. The position of the active galactic nucleus of the central galaxy NGC1275 in the Perseus cluster is precisely seen by SXI, while the positional difference of line-of-sight velocity dispersion of the hot intracluster medium is measured inside by SXS. From the observation of Crab nebula, we obtain the on-pulse hard X-ray image with HXI as well as the time-averaged image in which the torus of the pulsar wind nebula can be seen. [ABSTRACT FROM AUTHOR]

In early 2015 the artist behind the photographic collection Bariónica entered it in video form into the European Space Agency's (ESA) Ode to Hubble competition -- a public video competition organised to celebrate the 25th anniversary of the Hubble Space Telescope1. The photographic collection aims to show the connection between cosmic matter and the matter which constitutes mankind, using images and ideas from astronomy to symbolise the connection between what we are, and where we came from. On 24 April 2015, Hubble's 25th birthday, Bariónica was announced as one of two winning videos of the contest. In this article its creator, Desiré de Palacio, tells us about the fundamental ideas that led her to create her piece, and about the experience of being one of the contest winners. [ABSTRACT FROM AUTHOR]

Thousands of people from all over the world search the internet on a daily basis for the newest discoveries in astronomy: be it in the form of press releases, high resolution images, videos or even planetarium fulldome content. The growing amount of data available, combined with the increasing number of media files and users distributed across the globe, leads to a significant decrease in speed for those users located furthest from the server delivering the content. One solution for bringing astronomical content to users faster is to use a content delivery network. [ABSTRACT FROM AUTHOR]

The possibility of an automatic search for galaxy clusters in WISE infrared images using SDSS optical data is discussed. Preliminary results of applying such a procedure to fields of the 400 square degree (400d) X-ray galaxy cluster survey performed previously based on ROSAT pointing data are presented. We show that rich galaxy clusters can be detected in the WISE infrared survey both at moderate redshifts and up to high redshifts, z ≈ 1-2. These data can be used to identify clusters detected in X-rays or via the Sunyaev-Zeldovich effect. [ABSTRACT FROM AUTHOR]

This paper discusses facets of visual communication by way of images, graphs, diagrams and tabular material. Design types and elements of graphical images are presented, along with advice on how to create graphs, and on how to read graphical illustrations. This is done in astronomical context, using case studies and historical examples of good and bad graphics. Design types of graphs (scatter and vector plots, histograms, pie charts, ternary diagrams and three-dimensional surface graphs) are explicated, as well as the major components of graphical images (axes, legends, textual parts, etc.). The basic features of computer graphics (image resolution, vector images, bitmaps, graphical file formats and file conversions) are explained, as well as concepts of color models and of color spaces (with emphasis on aspects of readability of color graphics by viewers suffering from color-vision deficiencies). Special attention is given to the verity of graphical content, and to misrepresentations and errors in graphics and associated basic statistics. Dangers of dot joining and curve fitting are discussed, with emphasis on the perception of linearity, the issue of nonsense correlations, and the handling of outliers. Finally, the distinction between data, fits and models is illustrated. [ABSTRACT FROM AUTHOR]

We present an original method for reconstructing a 3-D object having two spatial dimensions and one spectral dimension from data provided by the infrared slit spectrograph on board the Spitzer Space Telescope. During acquisition, the light flux is deformed by a complex process comprising four main elements (the telescope aperture, the slit, the diffraction grating, and optical distortion) before it reaches the 2-D sensor. The originality of this work lies in the physical modeling, in integral form, of this process of data formation in continuous variables. The inversion is also approached with continuous variables in a semi-parametric format decomposing the object into a family of Gaussian functions. The estimate is built in a deterministic regularization framework as the minimizer of a quadratic criterion. These specificities give our method the power to over-resolve. Its performance is illustrated using real and simulated data. We also present a study of the resolution showing a 1.5-fold improvement relative to conventional methods. [ABSTRACT FROM PUBLISHER]

Three-dimensional (3-D) maps of the electron density and temperature in the solar atmosphere can be tomographically reconstructed from two-dimensional images that are measured by a variety of ground-based and space-based instruments. The electron density and temperature of the solar corona are fundamental parameters for understanding the physical mechanisms that contribute to space weather, or physical phenomena that can, in extreme cases, have adverse effects on Earth and the near-Earth space environment. New signal processing methods are required to take full advantage of the rich and complex suite of observations that are available from the current generation of Sun-observing spacecraft. In particular, this paper provides signal models and corresponding optimal state estimation methods for reconstructing the dynamic 3-D electron density and temperature structures in the solar corona with focus on the many challenges associated with solar tomography. [ABSTRACT FROM PUBLISHER]

The article discusses the highlights of the 2009 Astronomy Visualisation Workshop at the California Academy of Sciences in San Francisco, California. Particular focus is given to the Academy's motivations for hosting the workshop. Also mentioned are the workshop's planetarium production, a demonstration by Michael Broxton of Ames Research Center on his work on neocartography, and a description by Kimberly Kowal Arcand of her research into the aesthetics of astronomical imagery.

Columnist Charles Day describes how the Internet boosts the beauty and power of astronomical images compared to seeing those same images on paper. [ABSTRACT FROM PUBLISHER]

A cartoon is presented regarding astronomical imaging.