NGC 4414: A Telling Spiral . ... the Hubble Heritage Team ( AURA / STScI / NASA ) Explanation: How far away is this galaxy? ... Spiral galaxy NGC 4414 contains many Cepheid variable stars that oscillate in a way that allows astronomers to estimate their distance. From analyzing distances to galaxies like this, some astronomers have recently announced that they have again refined their estimate of the expansion rate of the universe . ... NASA Web Site Statements, Warnings, and Disclaimers . ...

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... June 9, 1999 . NGC 4414: A Telling Spiral . ... the Hubble Heritage Team ( AURA / STScI / NASA ) . Explanation: How far away is this galaxy? ... Spiral galaxy NGC 4414 contains many Cepheid variable stars that oscillate in a way that allows astronomers to estimate their distance. ... NGC 4414 shows many classic spiral galaxy features, including thick dust lanes , a central region rich in old red stars, and winding spiral arms glowing with young blue stars. ... About APOD > . ...

... Posts tagged ?variable selection? ... arXiv:stat.ME:0910.2585] . Variable Selection and Updating In Model-Based Discriminant Analysis for High Dimensional Data with Food Authenticity Applications . ... Entries RSS . ... 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 . ...

GCVS Research Group: . Recent publications . Kazarovets E.V., Samus N.N., Durlevich O.V., Kireeva N.N., Pastukhova E.N., The 81st Name-List of Variable Stars. ... Kazarovets E.V., Samus N.N., Durlevich O.V., Kireeva N.N., Pastukhova E.N., The 80th Name-List of Variable Stars. ... Samus N.N., Kazarovets E.V., Kireeva N.N., Pastukhova E.N., Durlevich O.V. General Catalogue of Variable Stars: Current status and new Name-lists Odessa Astronomical Publications, 2010, V. 23, p. 102-105. ...

Dr John Butler fine tuning the recently restored Calver telescope at Armagh Observatory. Image courtesy Miruna Popescu) Dr John Butler, recently retired research astronomer at the Armagh Observatory, has been awarded the MBE in the Queen's Birthday Honours, for services to science. ... John worked for a number of years at Dunsink Observatory, Dublin before joining the staff of the Armagh Observatory in 1973. ... A Short History of Armagh Observatory by C.J. Butler . ...

... CEPHEID VARIABLE STARS: A Cepheid variable or Cepheid is a member of a particular class of very luminous, massive variable stars with pulsation periods of 1-70 days. ... The relationship is calibrated using data collected from Cepheids whose distances are determined by other means. ... Browse through the 68 CCD fits images he sent you, using ds9 and locate the Cepheid variable. ... Image credits: ESA - "http://sci.esa.int/science-e-media/img/20/cepheid-variables.jpg" . ...

... Stars . ... Cepheid variable stars have been known since the 18th century. ... Regularly brightening to a peak over days, weeks or months before fading these variable stars were remarkable curiosities to astronomers in past centuries.€а The term Cepheid is taken from the star Delta Cephei in the constellation of Cepheus, which was identified as variable€а in 1784 by the teenaged prodigy John Goodricke (1764-96). ... Tweets that mention Cepheids: Inconstant Stars which break the rules | ...

... 2002 October 3 . V838 Mon: Mystery Star . ... Explanation: A leading candidate for the most mysterious star found in recent times is variable star V838 Monocerotis . At a distance of about 8,000 light-years, V838 Mon was discovered to be in outburst in January of this year. Initially thought to be a familiar type of classical nova , astronomers quickly realized that instead, V838 Mon may be a totally new addition to the astronomical zoo. ... About APOD | ...