... 2007 December 30 . Mammatus Clouds Over Mexico . ... Explanation: Normal cloud bottoms are flat because moist warm air that rises and cools will condense into water droplets at a very specific temperature, which usually corresponds to a very specific height. After water droplets form that air becomes an opaque cloud. Under some conditions, however, cloud pockets can develop that contain large droplets of water or ice that fall into clear air as they evaporate. ... About APOD | ...

Our group includes both theoreticians and observers working on problems related to many different aspects of star formation. You can learn more about us by following the links provided here below. We will try to keep these pages updated as frequently as possible, however do not hesitate to contact us directly if you encounter problems while browsing or do not find the specific information that you are looking for. Click on the following for more information . Our Group . ...

... HST Overview . ... CONTENTS: -Update on STIS Situation -Calibration Close-out Highlights -Doppler Correction Errors -Cross-dispersion Plate Scale Corrections -CALSTIS V2.17 Release Notes -Support for STIS Imaging Data in Multidrizzle -Recently published Instrument Science Reports (ISRs) -Fix for CALHRS flux error +----------------------------------------------------------+ Update on STIS Situation We provide an update on the current status of STIS operations and future plans for the instrument. ...

... Magnetic storms online . ... Geomagnetic activity forecast . ... December : 2015 . ... No magnetic storm is expected . From 2 December 2015 to 28 December 2015 the following magnetic storms and disturbances are expected: . December 06, 2015 geomagnetic disturbances . ... December 08, 2015 geomagnetic storm of level G1 (minor) . ... December 21, 2015 geomagnetic storm of level G2 (moderate) . ... December 16, 2015 geomagnetic storm of level G1 (minor) 2 December 2015 - 28 December 2015 . ...

... In spite of the good potential possibilities, some of the station "Dnepr" design characteristics did not allow us to apply the usual special IS radar measurement methods. ... Thus for IS signal measurements at the "Dnepr" station, we have developed special methods for recording and processing IS signals in order to determine plasma ionospheric parameters. ... Equations (4-5) from the basis for data post processing to obtain ionosphere parameters. ...

Astronomy Picture of the Day . ... 20.01.1999 . ... January 1999 . ... 1999 2000 . ... NASA Web Site Statements, Warnings, and Disclaimers . NASA Official: Jay Norris. ... A service of: LHEA at NASA / GSFC . ... U. Based on Astronomy Picture Of the Day . Publications with keywords: extrasolar planet - dust - infrared - young stars . Publications with words: extrasolar planet - dust - infrared - young stars . ... A Giant Planet for Beta Pic . Young Star Cluster Westerlund 2 . ...

... PmWiki . ... Basic Variables | ... Page variables have the form {$ variable } , and can be used in page markup or in certain formatting strings in PmWiki . ... Note that these variables do not necessarily exist in the PHP code, because they have to be determined for a specific page. ... Prefixing the variable name with an asterisk (*) means the variable's value is related to the target page or main (body) page. ... Title} - page title (may differ from Name), as in "Page specific variables" . ...

August 26, 2006, . ... The 2 nd Asian-Pacific Astronomy Olympiad to be held in Vladivostok and Ussurijsk (Far East of Russian Federation). Preliminary dates for the 2 nd Asian-Pacific Astronomy Olympiad are December 4-11 (a couple weeks later than the 11 th IAO in Bombay ). ... For the teams which ask for Russian visa - together with the personal data for visas (or before). E-mails for sending the applications . ... The Asian-Pacific Astronomy Olympiad 2006 - last information . ...

Current scientific project and their status . General description of our projects. The scientific problematics. The goals of the projects. Galaxy formation and evolution in cosmic voids . RFBR project 14-02-00520) . 19 December 2014 . Study of galaxies in nearby voids: cosmological perspective . RFBR project 11-02-00261) . ... RFBR project 06-02-16617) . 15 January 2008 . One of the important Laboratory directions is creation new BCG samples. ...

Astronomy Discussion Forums . ... A Number Is A Very Specific Thing . ... Post Message | ... Posted by Harvey on October 9, 2002 16:41:15 UTC . ... When you use the word 'number', you are introducing a specific kind of symbol that is known within the context of mathematics. ... You know what - harvey1 - October 9, 2002 - 20:53 UTC . ... www.astronomy.net . ... Forum posts are Copyright their authors as specified in the heading above the post. "dbHTML," "AstroGuide," "ASTRONOMY.NET" & "VA.NET" . ...

... The IB_TAIL magnetic conjugations with the others Spacecraft . ... ASCII file description | Plot description | ... ASCII file | real time plot . ... The IB_TAIL magnetic conjugations with the groundbased magnetic observatories . ... The IB_TAIL magnetic mapping polar diagram, and ASCII files for each decade of month: . ... ASCII files description | DEC 1 (ASCII file, size more then 350Kb!) ... Back to the IB_TAIL Home page. Updated 24 November, 1999 . ... INTERBALL mission  ...

... S.P. KOROLEV ROCKET AND SPACE CORPORATION ENERGIA . ... OAO RSC "Energia" . ... Company's History . ... History . Brief History of Rocket and Space Technology . ... ISS Russian Segment . ... Experiments and Researches from 2013 . ... Support of the Station functionality; . ... Onboard photographic and video recording of the ISS RS flight history and implementation of symbolic activities program. ... Support of the Space Station functionality; . ... 2015 JSC "S.P. Korolev RSC "Energia" . ...

... The Arecibo Galaxy Environment Survey . ... Gas Content of Galaxies with Extremely High Specific Star-formation Rates . ... SIGGMA: Survey of Ionized Gas in the Galaxy, Made with Arecibo . ... A Continuing Drift-Scan Pulsar Search at 327 MHz (AO327) . ... Followup Timing of 3 Pulsars Discovered in a 327 MHz Drift Survey . ... Arecibo Radar Orbit Refinement of Near-Earth Asteroid 99942 Apophis in June of 2013 . ... Arecibo Radar Observations of 18 Near-Earth Asteroids During July-December 2013 . ...

Russian . ... text in Russian) . ... The Behaviour of the Bz Component of the Magnetic Field in Coronal Mass Ejections . ... Cooperation of IZMIRAN and Sternberg Astronomical Institute in the Study of the Sublimational Component of the Solar Coronal Radiation . ... Solar Wind and Magnetic Storms in the 24th Solar Activity Cycle . ... text in English) . ... The Solar Corona in the Light of TRACE Observations . ... Expeditions of Irkutsk Astronomers to Total Solar Eclipses in 1981--2012 . ...

... galaxies: bulges galaxies: clusters: general galaxies: clusters: individual: . ... star formation statistics stellar content structure Cosmology ( cosmology :) cosmic background radiation ( cosmology :) cosmological parameters cosmology : miscellaneous cosmology : observations cosmology : theory ( cosmology :) dark ages, reionization, first stars ( cosmology :) dark energy ( cosmology :) dark matter ( cosmology :) diffuse radiation ( cosmology :) distance scale ( cosmology :) early Universe (...

... The active time at each angular bin is the sum over frames of the active time contributions from all CCD pixels, within the node-specific telemetry window, which overlap the surface of the bin. ... The active time, per frame, of a normal pixel is the full frame integration time multiplied by the node-specific fractional exposure; bad pixels contribute no active time. ... If an event is rejected for this reason only, then its pixels remain normal in the exposure map. ...

OptInt PmWiki : Pm Wiki / Page specific variables . ... Page variables have the form {$ variable } , and can be used in page markup or in certain formatting strings in PmWiki. ... Prefixing the variable name with an asterisk (*) means the variable reflects the value related to the target page or main page. ... Namespaced} - spaced page name, as in "Page Variables" . ... Defines new Page Variable of name $CurrentSkin, which can be used in the page with {$CurrentSkin} (also for Conditional markup ). ...

... The best annual meteor shower is the Geminids, which are expected to peak this year on December 13th at 18h. Some activity will persist until about Dec 15/16. Unfortunately this year's display will be spoiled by a Full Moon at maximum, but you should still see some of the brighter meteors. ... This is a live count of meteor showers based on visual data entered through the IMO electronic report form. ... Saturday, 13 December 2008 19:03 . International Year of Astronomy, Ireland National Node . ...

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... Aurora from Space . ... Magnetic Storms . ... The "ring of fire" seen by satellite cameras around the polar caps (picture below) is probably created by electrons leaking from the tail's plasma sheet, whose magnetic field lines form a somewhat imperfect trap. ... One possible explanation involves the close association between auroral arcs and electric currents which flow along field lines between the ionosphere and distant space ( Birkeland currents ). ... Why no aurora at the magnetic poles? ...