... The TRACE images may be used without restrictions in publications of any kind. ... These two images, taken on 18 November 2000 at 15:54UT and 16:11UT, respectively, show such an event: the red circle in the image to the left shows a region where many loops are cooling, with bright loop tops (the intensity scales with the square root of the image to reduce the dynamic range). ... See also a collection of images related to the Sun, other cool stars, and solar-terrestrial effects . ... Images | ...

There is often dust associated with ionized regions. Compact HII regions usually have associated dust from a molecular cloud in which the massive star is being "born". ... For such stars the dust is not produced by the star, and a variety of dust features are observed. The planetary nebulae also usually have associated dust from the previous stage of evolution where they were either carbon stars or M-type giants. ... The feature near 11.5 microns in the IC 418 spectrum may be due to SiC dust. ...

... A typical density of energetic ions is 1 per cubic cm., and the ions are matched by electrons, generally of lower energy. ... This region is almost empty of plasma--typical density 0.01 ion/cubic cm., the "best vacuum" in the Earth's vicinity--but it contains a relatively strong magnetic field which, since it fills a large volume, can store appreciable magnetic energy, Many believe that this is the storehouse from which substorms draw their energy, releasing it quite rapidly. ...

... A typical density of energetic ions is 1 per cubic cm., and the ions are matched by electrons, generally of lower energy. ... This region is almost empty of plasma--typical density 0.01 ion/cubic cm., the "best vacuum" in the Earth's vicinity--but it contains a relatively strong magnetic field which, since it fills a large volume, can store appreciable magnetic energy, Many believe that this is the storehouse from which substorms draw their energy, releasing it quite rapidly. ...

... About ATNF overview . ... Australia Telescope Steering Committee . ... LMC H II Region Luminosities versus . Observed Ionizing Stars . ... These values are compared to the observed H II region luminosities, yielding an estimate for the mean fraction of H-ionizing photons that escape the local nebulae in this sample. We formally estimate that, overall, 0-51% of the ionizing radiation escapes the local H II regions and is available to ionize the warm, ionized medium in the LMC. ...

... High spectral, spatial and temporal resolution UV observations of the quiet Sun transition region show a highly structured and dynamical environment where transient supersonic flows are commonly observed. ... Estimates of the kinetic and enthalpy fluxes associated with these events show that explosive events are not important so far as solar coronal heating is concerned. ... In some cases, non-Gaussian line profiles are associated with supersonic flows in small magnetic loops. ...

... Colorful Star Clouds in Cygnus . ... Featured here is a star forming region rich in glowing gas and dark dust toward the constellation of the Swan (Cygnus), near the bright star Sadr. This region, which spans about 50 light years, is part of the Gamma Cygni nebula which lies about 1,800 light years distant. ... The rim of the blue galaxy pictured on the right is an immense ring-like structure 150,000 light years in diameter composed of newly formed, extremely bright, massive stars. ...

... We report on our ongoing project ``Infrared Study of HII Regions Associated with Small Clouds.' ... These IR data, combined with optical imaging (which will be obtained from the IAC-80 telescope), IRAS survey maps, and existing CO observations of the associated clouds, will allow us to undertake a detailed investigation of the gas-to-dust mass ratio, initial mass function and the star-formation efficiency in these complexes. ... CHECKPSF: check the PSF (Point Spread Function) model, . ...

... This thread contains a step-by-step recipe to extract MOS spectra of a point-like source observed in Imaging mode and to create associated response matrices, starting from a calibrated, concatenated event list (either produced with emproc or available as PPS product; here it has the assumed file name MOS.fits ). ... The users should note that the SAS metatask xmmselect allows them to interactively define source and background regions (via ds9) and to run backscale on the fly. ...

... Height from the galactic plane 65- 75 A11 --- IRAS IRAS name 81 A1 --- l_F12 limit flag on F12 (upper limit ) 83- 90 E8.2 Jy F12 IRAS flux density at 12 micron 92 A1 --- l_F25 limit flag on F25 (upper limit ) 94-101 E8.2 Jy F25 IRAS flux density at 25 micron 103 A1 --- l_F60 limit flag on F60 (upper limit ) 105-112 E8.2 Jy F60 IRAS flux density at 60 micron 114 A1 --- l_F100 limit ...

... Sun images . ... Sun flares . ... Active areas . September : 2009 . ... No sunspots and sunspot groups can be currently observed on the Sun's surface . The following H-alpha plages without spots can be currently observed on the Sun's surface . ... Coordinates . ... Coordinates and other characteristics of active regions are issued for September 09, 2009 00:31 UT . Last updated: September 10, 2009 00:00 UT . ... 7(499)132-65-96, Fax: +7(499)132-65-97 . ...

Polycyclic aromatic hydrocarbons in HII regions: correlation with metallicity . ... We have perfomed the aperture photometry of HII regions using infrared images from telescopes Spitzer and Herschel at passbands 3.6, 4.5, 5.8, 8.0, 24, 70 and 160 m. Emission of PAHs are observed at passbands 3.6 - 8.0 m, 24 m is emission likely of hot small particles and finally large particles are responsible for emission at 70 and 160 m. We determine abundances of PAHs using model of Draine Li (2007) . ...

True Color Image Gallery: Galactic SNR | Magellanic Cloud SNR . Common Name: IC 443 . ... Description: bright region within IC 443 . ... Radio Images Page . ... Exposure uf . ... Exposure uf Exposure time of unfiltered event file . Exposure f Exposure time of filtered event file . This a bright region within the large remnant IC 443. ... This region contains a knot (just resolved). ... see fit detail page for more about the fit. see chandra spectrum page for region used. ... 1.0" . ...

... Galaxies 99 Cosmic background with model of cloudy interstellar medium Yu. ... Figure 1: Averaged spectrum of the cosmic background I f in frequency range 0.25 200 MHz for the Galactic poles. ... First interpretation of the cosmic noise background spectrum at broad band frequency range 0.25 200 MHz with a model of the cloudy interstellar medium ISM is presented here. ... Synthesized background spectra I f for regions of the Galactic poles at the frequency range 0.25 200 MHz is presented in Fig. ...

... Research objects and scientific purposes . Space scientific program includes development and launch of two supersmall spacecrafts "Universitetskiy" and "Kompas-2" intended for monitoring of radiation conditions near the Earth. ... All the studies conducted in the near-Earth space are characterised by strong radiation fields. ... The circular polar orbits, which cover all the near-Earth space, are the most favorable for comprehensive studies of the radiation conditions near the Earth. ...

... Science Users Information > Science Activities > PhD Thesis Topics offered by ESO Faculty Members > Thesis Topic: Planetary Nebulae and HII regions in the Elliptical Galaxy NGC 5128 . ... NGC 5128 is the closest example of a giant early type (elliptical or S0) galaxy. Although often dubbed as a peculiar elliptical galaxy since it has a dust lane with recent star formation and an active galactic nucleus, the majority of early type galaxies have similar structures as revealed by recent surveys. ...

... This image shows clearly the 3-D structure of this star formation region: a large cavity, created by the radiation pressure from new-born stars located in the brightest area of the image, lies within a huge cloud of dust and gas. Identified as a truly indepedent star cluster, NGC 1980 is associated with this well-studied star formation region, around the brightest star seen at the bottom of this image, Iota Ori. ...

I-GALFA View of a Galactic Tangent Region . ... Image featured in NAIC Newsletter #46 . I-GALFA image of hydrogen gas in a tangent region outside the Sagittarius arm. ... Because we are viewing this gas in a direction closely aligned with (tangent to) its orbital motion, it appears to be moving away from us (we are orbiting the Galactic center with a similar speed, but our own motion in a different direction). ... The gas near 60 degrees longitude is being viewed tangent to its orbital motion. ...

GALAXIES cenA .tiff 40 Bright Radio Galaxy M31.tiff Nikon Andromeda Galaxy (note HII regions in spiral arms) ngc6744.tiff 40 NGC 6744 a face-on spiral clouds_20d.tiff H'blad The Magellanic Clouds our nearest neighbours Lmc_7.tiff Nikon The Large Magellanic Clouds Lmc_zoom.tiff Nikon Detail of previous image smc_7.tiff Nikon The Small Magellanic Clouds smc-zoom.tiff Nikon Detail of previous image 30dor_40_BVR.tiff 40 The 30 Dor ... B [OIII] Halpha trifid.tiff 40" The Trifid Nebula. ...

... 2013 July 10 . Large Sunspots Now Crossing the Sun . ... Explanation: One of the largest sunspot regions in recent years is now crossing the Sun. This region of convoluted magnetic fields may well produce a solar flare that releases a cloud of energetic particles into the Solar System. ... The darkest sunspot regions contain nearly vertical magnetic fields and are called umbras, while the surrounding bronze regions -- more clearly showing stringy magnetic flux tubes -- are called penumbras. ...