... 2001 April 15 . Diffraction Spikes: When Stars Look Like Crosses . ... Light scatters away from the original destination point ending up elsewhere and appearing as " diffraction spikes ." These annoying spikes steal precious light from the central image and hide light from fainter, more interesting stars. Above , astronomers are more interested in the half-circled point near the image center, than the cool-looking diffraction spikes from the bright star at the bottom. ... About APOD | ...

... WFPC2 , HST , NASA Explanation: Unusual appendages around bright stars are commonplace, but never seem to be mentioned. ... First, a telescope brings starlight falling over a large area to a small area . ... The wave nature of light causes it to deflect when passing near these rods. ... Above , astronomers are more interested in the half-circled point near the image center, than the cool-looking diffraction spikes from the bright star at the bottom. ... Light from the First Stars . ...

You Can Make Stellar Images Brighter . Articles | ... A few months ago I wrote an article titled "You Can’t Make Them Brighter". So why am I now writing that you can make them brighter. ... The image of a focused star is actually a small disk called the Airy disk, named after the 19 th century scientist Sir George Airy. ... For a given aperture, a smaller Airy disk means that the light is focused to a smaller disk and is therefore brighter. ... www.astronomy.net . About Astronomy Net | ...

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... Bringing news from across the Universe to children all around the world . ... Have you ever walked down the street late a night and seen a point of light in the distance? ... This is because things look fainter when they're farther away. ... That s what astronomers did in 1995 when the Hubble Space Telescope was pointed at a region of the night sky about the size a tennis ball would look if it were a 100-metres away. ... One camera, called MUSE, was used to take a fresh look at the patch of sky. ...

One of Planck's first images is shown as a strip superimposed over a two-dimensional projection of the whole sky as seen in visible light. ... The prominent horizontal band is light from our Milky Way galaxy. The Planck image shows how the sky looks at millimeter-long wavelengths. Red areas are brighter, blue areas are darker. The large red strips show the Milky Way. ... Planck is measuring the sky at nine wavelengths of light, one of which is shown here. ...

The HST images of GRB 990510. The images were obtained on 8.1 June 1999 (UT), 17.9 June 1999 and 29 April 2000. ... On this page we present the Hubble Space Telescope images of GRB 990510. ... The field of GRB 990510 was imaged by HST on 8.1 June 1999 (UT) 17.9 June 1999 (UT) and 29 April 2000 with the STIS/CCD camera in Open Filter (50CCD) mode. ... The suggestion of a host in the June 1999 image, led us to re-image the field in April 2000. ... The 29 April 2000 image of the field of GRB 990510. ...

... Armagh Planetarium . ... Universe . ... Posted on January 19, 2012 | ... Continue Reading.. ... 1 Comment A new image of the Omega Nebula reveals amazing detail in a cosmic landscape of gas clouds, dust and newborn stars.€а Captured by the Very Large Telescope (VLT) at the [ ] . ... Welcome to our annual guide to what the Universe has waiting [ ] . ... The furthest you can travel from home across the [ ] . ... This local school has its own observatory and astronomy club for the students [ ] . ...

... More information on books, telescopes, clubs, etc. is available in the Getting Started section. ... For more information call 617-495-7461. Boston University Astronomy Department - Public telescopic observing is held every clear Wednesday night. ... Boston Museum of Science - For more information and admission prices call 617-723-2500. ... For information and admission prices call 508-929-2700. ... Springfield Telescope Makers , VT. ... Copyright (c) Amateur Telescope Makers of Boston, Inc. ...

... The bright supernova (hereafter SN) in the galaxy NGC 4527 was first sighted by S. Knight (USA) on April 13.17UT at magnitude ~14.0v. The report of the sighting was subsequently forwarded by phone to the AAVSO. ... SN 1991T. The galaxy NGC 4527 is an Sb(s)II type galaxy with an apparent Blue magnitude of 11.32 (Shapley-Ames, 1981). ... An analysis of this event utilizing visual observations by amateurs, plus a light curve is presented.. ... THE LIGHT CURVE: . ... ISN SN 1991T web page . ...

... Armagh Observatory, College Hill, Armagh BT61 9DG, +44 (0)28 3752 2928 . ... Aurora . ... Corona . Fireballs . ... Zodiacal Light . ... The first thing to do is get acquainted with what the night sky looks like. ... The National Schools Observatory web site has very good horizon views of the sky for the current night. ... If the object is moving slowly across the sky then it may be one of the larger satellites. ... Cloudbait Observatory - October 2002 . ... October 2003 Aurora at Armagh . ...

... Bad Astronomy . ... Mad Science . ... if hubble was pointed at earth, what could it resolve? is it too bright? ... This type of image is called a ``flat field'', because you want the field of view to look as flat as possible. In space there aren't any flat fields you can use, but we do have one right here: the Earth. ... It takes a lot of sophisticated computer processing to turn this into a real flat field for Hubble to use, but luckily there are a lot of smart people working on the problem. ...

... 2000 April 24 . Reflection Nebula M78 . ... Explanation: An eerie blue glow and ominous columns of dark dust highlight M78, a bright reflection nebula in the constellation of Orion . The dust not only absorbs light, but also reflects the light of several bright blue stars that formed recently in the nebula. ... M78 belongs to the larger Orion Molecular Cloud Complex that contains the Great Nebula in Orion and the Horsehead Nebula . ... About APOD | ...

... SEARCH ASP SITE: Match ALL words Match ANY word . ... ASP Conference Series . ... Accidental Astrophysics: The Devil's In the Magnitudes, Part II . ... The star second to the Sun in brilliance is Sirius. ... Recall the magnitude system, passed down to us through a hundred generations of sky watchers, as a means of quantifying stellar brightness ("Accidental Astrophysics," May/June, p. 9). ... Yes, it is a magnitude difference, but that difference is due to the distance between us and the star. ...

... Posts tagged ?light curves? ... If you find any problems of viewing the slog, please notify me. ... 2007? ... Tags: ARCH , Bayesian Block , challenges , change point problem , GARCH , light curves , summer school , X-ray . ... Algorithms arXiv Astro Bad AstroStat Bayesian CHASC Cross-Cultural Data Processing Fitting Frequentist Galaxies gamma-ray High-Energy Imaging Jargon Job Languages MC MCMC Meta Methods Misc News Nuggets Objects Optical Physics Quotes Spectral Stars Stat Timing Uncertainty X-ray...

In this gallery are many images of Low Surface Brightness Galaxies which have recently been discovered and analyzed. ... The central surface brightness of this galaxy is 24.28 . Malin 2 This galaxy is another huge disk galaxy with a scale length of 15 kpc and a redshift of 15000 km/a. The high surface brightness knot in one of its spiral arms actually has the same color, luminosity and H-alpha equivalent width as the entire Large Magellanic Cloud . ... Truly it is a Low Surface Brightness Galaxy. ...

... About ATNF overview . ... Australia Telescope Steering Committee . ... Australia Telescope User Committee . ... Staff list | ... Australia Telescope Compact Array . ... Australia Telescope Online Archive (ATOA) . ... VLBI . ... Arch | ... Australia Telescope 20GHz Survey . ... From: "Sergei Gulyaev" <sergei.gulyaev_at_aut.<!--nospam-->ac.nz> . ... Lewis Woodburn" <lwoodbur_at_aut.<!--nospam-->ac.nz>, <mahmah98_at_aut.<!--nospam-->ac.nz>, . ... First observations show that in general pointing is not ...

scripts · Made a comparison with SCISIM ray trace that replicates each observation Main Analysis Steps · Select regions for each camera and run esas · Extract spectra and background · Made an . arf that is a guess for typical off axis angle ( fn(E) knowing only a single reflection occurs ) · Assume source spectrum of a LMXRB e.g. const*phabs*(diskbb+comptt) probably the detailed spectrum doesn't matter to 1st order · Also require an ...

... The Pleiades star cluster, also known as the Seven Sisters and Messier 45, is a conspicuous object in the night sky with a prominent place in ancient mythology . ... The stars in the Pleiades are thought to have formed together around 100 million years ago, making them 1/50th the age of our sun, and they lie some 130 parsecs (425 light years ) away. ... Data for these stars are listed in a table below. ... Yes . ... WEBDA Pleiades cluster data . ... M45: The Pleiades Star Cluster (2007 November 18) ...

... A comparison of the computed and experimental relations F max ( H), as well as comparison of drift scans of point sources across different horizontal cross-sections of the BP with the corresponding computed cross-sections were made. ... The drift scans of the point source 3С84 (H=87 o ) at the wavelength 7.6 cm across the horizontal cross-sections of the BP (black lines) and the computed horizontal cross-sections of the BP corresponding to them (red lines). ...