... These ice-crystals act together like millions of miniature ice mirrors, with external and internal reflections from different faces creating arcs and halos of different radii. An amazing display of pyramid ice crystal halos was captured on June 5 above Tampere , Finland . ... In contrast, thin and flat falling ice crystals will produce a halo of 22 degrees only. ... Publications with keywords: halo - ice crystals . Publications with words: halo - ice crystals . ... A Sun Halo Over Tennessee . ...

... 2006 April 11 . A Sun Halo over Utah . ... This fairly common sight occurs when high thin clouds containing millions of tiny ice crystals cover much of the sky. ... Because most of the crystals have a similar elongated hexagonal shape, light entering one crystal face and exiting through the opposing face refracts 22 degrees , which corresponds to the radius of the Sun Halo . ... Lecture: APOD editor to give public talk in Princeton tonight (April 11) . ... About APOD | ...

... Главная . ... Новости . ... Проекты . Любителям астрономии . Проект ISON . ... Подробнее . ... Категория: Новости проекта ISON . ... Метки: Космический мусор ,љ Астероиды ,љ Гамма-всплески ,љ Любителям астрономии ,љ Кометы љ . ... Метки: Космический мусор ,љ Астероиды ,љ Любителям астрономии љ . ... Новости обсерваторий проекта] - Обсерватория Кубанского государственного университета от Иванов А - 09.04.2016 11:08:49 . ... 1999-2013 Copyright "Астрономия и Телескопостроение" . ...

This is the homepage of Andrew Fruchter, an astronomer on the staff of the Space Telescope Science Institute . ... Here you can look at an HST images of the optical counterparts of gamma-ray bursts and their host galaxies. ... Therefore, substantial information on the fine scale structure of objects can be obtained by offsetting the pointing of the telescope between exposures and then combining these "dithered" exposures into a single image. ...

... 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 > . ...

... Bad Astronomy . ... Mad Science . ... Site Info . ... Public Talks . ... Keep Bad Astronomy close to your heart, and help make me filthy rich. ... Who is this guy who calls himself "The Bad Astronomer?" ... First, yes, I am a real live astronomer (when people ask me what astronomers do, I tell them "They astronom !" ... These are emitted by powerful objects like black holes, exploding stars, and super-dense neutrons stars. ... Finally, am I really a bad astronomer? ... 2008 Phil Plait. ...

Over the coming weeks an international team, including Simon Jeffery , Vincent Woolf and Amir Ahmad of the Armagh Observatory, will use over fifteen different telescopes to make over one hundred nights of observations of just one star to learn about its internal structure. ... Although the approach has been used before, this may be the first time that a global asteroseismology project has tried to measure both light and spectrum variations at the same time for any star apart from the Sun. ...

... Under certain conditions, like those in the nucleus of a QSO, all atoms can be made to emit light at particular wavelengths. ... If that source is approaching the observer, the wave is squashed up onto itself making the wavelength shorter. ... This is redshift. ... You can see how the section of the QSO spectrum which we observe changes with redshift. ... We then see how far we had to slide the observed spectrum along the scale to make it match and that is the objects redshift. ... The 2QZ team . ...

... ADS doc The Westerbork Northern Sky Survey (WENSS) is a radio survey made with the WSRT at wavelengths 92 and 49 cm. At 92 cm the entire sky above declination 30 degrees is covered. ... To move grating rings of the map 6 different baseline settings are used, so 1 mosaic data block involves 72 hours of observational data. ... As a result the final catalogue will consist of 300,000 sources at 92 cm and 60,000 at 49 cm. ... With the WSRT high quality wide field polarization maps can be made. ...

The database contains references to the papers, data files and links to the Internet resources related to measurements and calculations of the optical constants in the wavelength interval from X-rays to radio domain. ... References to some useful books and reviews on the subject (e.g. the classical handbooks edited by E.D.Palik) and links to Internet collections of optical constants and personal WWW pages with related software were also placed in the database. You have arrived at our welcome page. ...

Gain curves for various receivers and freq (ps) ( .pdf ) are plotted versus zenith angle. (last updated 22nov05) . ... The colors are for different receivers. For the same receiver, different frequency measurements use different plotting symbols. ... The solid line has averaged over azimuth, the dashed line has taken the maximum azimuth value for each measurement (all at a za of 10 degrees). ... For more info on the gain curve fits and their location see gain curves fits at ao . ...

... Observing . ... Solar Observing . ... April 3 (SUN) - Solar Observing, Central Park , Manhattan . ... APRIL'S SKY . ... Lecture Series at the American Museum of Natural History The Amateur Astronomers Association is proud to present an astronomy lecture series from October through May each year for our members and the .. ... The€аAmateur Astronomers Association of New York€аwas organized in 1927 to promote the study of Astronomy, emphasizing its cultural and inspirational value. ...

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The Sun is our nearest star and the source of energy for life on Earth. ... For centuries astronomers wondered whether they were clouds floating in the Sun's atmosphere, but we now know that they really are huge regions of magnetic field, about as intense as the field at the poles of an iron magnet. ... Such abrupt events were named solar flares , and what made them especially interesting was that occasionally, after a prominent flare, a magnetic storm would erupt on Earth. ...

... CCD array Lens delays some rays more than others So that rays from different directions end up in step at different places Electric field Distribution FOURIER TRANSFORM Image The Fourier Transform Comte Jean Baptiste Joseph Fourier 1768-1830 All waveform are formed from a sum of sine waves In general, any function can be composed "synthesised" - from a number of sines and cosines of different periods and amplitudes. ...

... Planets . ... Stars . Exoplanets . ... Most exoplanets so far discovered fall into the category of тАШhot JupitersтАЩ, these are giant planets orbiting very close to their parent star. ... Note that we have discovered so many hot Jupiters because they are the easiest type of planet to find, they are not necessarily particularly common in the galaxy. ... Subsequently several similar hot and€а fuzzy worlds have been discovered the same way, proving this that this planet is not a one-off oddball. ...

... Astrophysics Group . ... Surveys and Catalogues . 10C . ... AMI-Planck . ... FIRST . ... The 15.7-GHz, 10C Survey was carried out using the Arcminute Microkelvin Imager (AMI) Large Array (LA), which is operated by the Cavendish Astrophysics Group at Lord?s Bridge, Cambridgeshire. ... The first 10C Survey results from an area of тЙИ 27 sq. degrees complete to 1 mJy and тЙИ 12 sq. degrees complete to 0.5 mJy have now been released. ... The 10C catalogue is available in ASCII and PDF formats. ...

home publications > mercury . SEARCH ASP SITE: Match ALL words Match ANY word . ... ASP Conference Series . ... Steering by Different Stars? Astronomers and the Dark-Sky Movement . ... Photo courtesy of the International Dark-Sky Association. by Susan McGowan . ... According to Arthur Upgren, senior research scientist at Yale University and emeritus professor of astronomy at Wesleyan University, only 17% of ASP members were also members of the International Dark-Sky Association in 2001. ...

... Archives . ... To complicate matters, we have also started to use another term called ?data model? ... Comment ( RSS ) | ... The challenges lie in developing computer scientific theories, most of which can be associated with already existing theories from mathematical statistics. ... I recommend a book by Thomas and Cover, Elements of Information Theory (Wiley Series in Telecommunications and Signal Processing) and a paper by Shannon, A mathematical theory of communication. ... Chandra Blog . ...

... Meta Index / Home Page / Errors . ... warning . ... For instance, if the PROPOSAL information record is missing the user can add a fake one to the SOSF without this having any effect on the data reduction. corrective action: Continue. ... For a certain exposure in the ODF one of the parameters was not found in the housekeeping data. ... RGS, EPN, OM : the current exposure is found to contain more than one distinct calibration mode. corrective action: In the summary file: MODE = UNDEFINED . ... error...