205 resultados para Bright, John, 1811-1889.


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Recent searches by unbiased, wide-field surveys have uncovered a group of extremely luminous optical transients. The initial discoveries of SN 2005ap by the Texas Supernova Search and SCP-06F6 in a deep Hubble pencil beam survey were followed by the Palomar Transient Factory confirmation of host redshifts for other similar transients. The transients share the common properties of high optical luminosities (peak magnitudes similar to -21 to -23), blue colors, and a lack of H or He spectral features. The physical mechanism that produces the luminosity is uncertain, with suggestions ranging from jet-driven explosion to pulsational pair instability. Here, we report the most detailed photometric and spectral coverage of an ultra-bright transient (SN 2010gx) detected in the Pan-STARRS 1 sky survey. In common with other transients in this family, early-time spectra show a blue continuum and prominent broad absorption lines of O II. However, about 25 days after discovery, the spectra developed type Ic supernova features, showing the characteristic broad Fe II and Si II absorption lines. Detailed, post-maximum follow-up may show that all SN 2005ap and SCP-06F6 type transients are linked to supernovae Ic. This poses problems in understanding the physics of the explosions: there is no indication from late-time photometry that the luminosity is powered by Ni-56, the broad light curves suggest very large ejected masses, and the slow spectral evolution is quite different from typical Ic timescales. The nature of the progenitor stars and the origin of the luminosity are intriguing and open questions.

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We present photometric and spectroscopic observations of a luminous Type IIP Supernova (SN) 2009kf discovered by the Pan-STARRS 1 (PS1) survey and also detected by the Galaxy Evolution Explorer. The SN shows a plateau in its optical and bolometric light curves, lasting approximately 70 days in the rest frame, with an absolute magnitude of M-V = - 18.4 mag. The P-Cygni profiles of hydrogen indicate expansion velocities of 9000 km s(-1) at 61 days after discovery which is extremely high for a Type IIP SN. SN 2009kf is also remarkably bright in the near-ultraviolet (NUV) and shows a slow evolution 10-20 days after optical discovery. The NUV and optical luminosity at these epochs can be modeled with a blackbody with a hot effective temperature (T similar to 16,000 K) and a large radius (R similar to 1 x 10(15) cm). The bright bolometric and NUV luminosity, the light curve peak and plateau duration, the high velocities, and temperatures suggest that 2009kf is a Type IIP SN powered by a larger than normal explosion energy. Recently discovered high-z SNe (0.7

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This article provides a discussion of the political thinking of John P. Mackintosh (1929–1978) around the debate over Scottish devolution, and the constitutional reform of the UK, during the 1960s and 1970s. The article explores Mackintosh's ‘Union State’ vision of the UK and connects this to his interest in, and study of, the Northern Ireland experience of devolution from 1921 to 1972. It also considers the significance of Mackintosh's confrontations with Scottish nationalism and suggests that his unionism was representative of a more authentic and rooted tradition than is usually acknowledged. The article offers an evaluation of Mackintosh's legacy and considers the extent to which the questions he posed, and the lines of argument he advanced, have retained their relevance and interest in the new context of partial devolution in the UK, and in the current period of renewed constitutional speculation and debate over the future of the Union and the UK.

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This edition of Milton’s Epistolarum Familiarium Liber Unus and of his Uncollected Letters, will appear as 672 pp. of The Complete Works of John Milton Volume XI, eds. Gordon Campbell and Edward Jones (Oxford University Press, forthcoming 2016). A diplomatic Latin text and a new facing English translation are complemented by a detailed Introduction and commentary that situate Milton’s Latin letters in relation to the classical, pedagogical and essentially humanist contexts at the heart of their composition. Now the art of epistolography advocated and exemplified by Cicero and Quintilian and embraced by Renaissance pedagogical manuals is read through a humanist filter whereby, via the precedent (and very title) of Epistolae Familiares, the Miltonic Liber is shown to engage with a neo-Latin re-invention of the classical epistola that had come to birth in quattrocento Italy in the letters of Petrarch and his contemporaries. At the same time the Epistolae are seen as offering fresh insight into Milton’s views on education, philology, his relations with Italian literati, his blindness, the poetic dimension of his Latin prose, and especially his verbal ingenuity as the ‘words’ of Latin ‘Letters’ become a self-conscious showcasing of etymological punning on the ‘letters’ of Latin ‘words’. The edition also announces several new discoveries, most notably its uncovering and collation of a manuscript of Henry Oldenburg’s transcription (in his Liber Epistolaris held in Royal Society, London) of Milton’s Ep. Fam. 25 (to Richard Jones). Oldenburg’s transcription (from the original sent to his pupil Jones) is an important find, given the loss of all but two of the manuscripts of Milton’s original Latin letters included in the 1674 volume. The edition also presents new evidence in regard to Milton’s relationships with the Italian philologist Benedetto Buonmattei, the Greek humanist Leonard Philaras, the radical pastor Jean Labadie (and the French church of London), and the elusive Peter Heimbach.

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We use high spatial resolution observations and numerical simulations to study the velocity distribution of solar photospheric magnetic bright points. The observations were obtained with the Rapid Oscillations in the Solar Atmosphere instrument at the Dunn Solar Telescope, while the numerical simulations were undertaken with the MURaM code for average magnetic fields of 200 G and 400 G. We implemented an automated bright point detection and tracking algorithm on the data set and studied the subsequent velocity characteristics of over 6000 structures, finding an average velocity of approximately 1 km s(-1), with maximum values of 7 km s(-1). Furthermore, merging magnetic bright points were found to have considerably higher velocities, and significantly longer lifetimes, than isolated structures. By implementing a new and novel technique, we were able to estimate the background magnetic flux of our observational data, which is consistent with a field strength of 400 G.