... Comet Animation . ... Comet structures are diverse and very dynamic, but they all develop a surrounding cloud of diffuse material, called a coma, that usually grows in size and brightness as the comet approaches the Sun. ... As comets approach the Sun they develop enormous tails of luminous material that extend for millions of kilometers from the head, away from the Sun. ... The evaporated molecules boil off and carry small solid particles with them, forming the comet's coma of gas and dust. ...

... Bad Astronomy . ... Bitesize Astronomy . ... Last week's Snack talked about how black holes can affect the environment around them in such a way as to be very bright . ... It's a common misconception that black holes always have matter swirling into them. ... As this matter gets closer and closer to the black hole it piles up and a large, fairly flat disk forms. This is called the accretion disk , because matter from this disk accretes (that is, falls in) on the black hole. ... 2008 Phil Plait. ...

... Magnetic Storms . ... Cosmic Rays . ... Energetic Particles . ... Solar fast Particles . We cannot observe the way the distant universe accelerates cosmic rays or produces energetic photons, but acceleration processes also occur on our Sun , though on a much more moderate scale. ... That is why such events are often missed by cosmic ray detectors near the equator, where the lowest energies are excluded by the Earth's magnetic field. ... Should we be concerned about solar energetic radiation? ...

... Andromeda Island Universe . ... Gamma Ray Burst, Supernova Bump . ... During April and May, attention has been focused on the western evening sky, presenting its spectacle of bright planets and crescent moons shortly after sunset. Meanwhile, the Sun itself has not been just sinking quietly below the horizon. Tail Wags of Comet Ikeya Zhang . ... The star that appears to powers the nebula, although young and bright, does not seem hot enough to create some of the colors observed. ... 1999 2000 . ...

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. ...

... 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 | ...

... To be read in conjunction with Section 4.11 of the WFPC2 Instrument Handbook , -Version 4.0. ... 1 The second study found evidence that CTE loss for faint stars has increased with time (Whitmore, 1998). The primary observational consequence of CTE loss is that a point source at the top of the chip appears to be fainter than if observed at the bottom of the chip, due to the loss of electrons as the star is read out down the chip (see Figure 1 ). ... Last updated: 06/16/98 10:38:00 . ...

... Next, the screen displays "Press 0 to align or Mode for Menu." Press "0" if you wish to begin Automatic alignment (or Easy Align, depending on your telescope model), or press Mode if you wish to choose a manual alignment method ("Automatic Alignment" displays, and you can press MODE to go through the menu to find other alignments). ... Note: If you press the "?" key while "Ctr Brightest Star" displays, the alignment star that AutoStar has chosen will display. ... Alignment successful" displays. ...

True Color Image Gallery: Galactic SNR | Magellanic Cloud SNR . ... Chandra Proposer's Guide pile up section ] During frame readout, the ACIS CCDs take 40 microsec to (parallel) transfer the charge by one pixel. As a result of this, each frame readout, each pixel is exposed for 40 microsec to a source (plus cosmic X-ray background) at each location along its column. ... Note also that the image does not just trail, it extends along the whole column. ... Chandra Supernova Remnant Catalog . ...

... V838 Mon is a member of a new class of eruptive variables which appear as a peculiar novae having late K-M type spectra in their outburst. Before its outburst, it was a wide binary system of B3V type stars. ... The B3V companion was seen in the outburst in the UV spectrum taken with HST (Rauch et al., ... In the latest spectra, the light of B3V companion was predominating in the short-wave photometric bands. ... CCD blue frames of V838 Mon before the eclipse (left) and in the eclipse (right). ...

... 2005 August 8 . Mars to Appear Normal This August . ... Regardless of numerous urban legends circulating, Mars will appear relatively normal in August. October is the best month to see Mars this year. ... As Earth catches up to Mars in their respective orbits around the Sun, Mars will keep rising earlier in the night. On 2005 October 30, Earth will have caught up to Mars and the planets will be the nearest to each other in their orbits -- this time around. ... About APOD | ...

... A new bright LBV (Luminous Blue Variable) star was detected in M33 galaxy. LBV stars are the most massive stars in the final stages of evolution before exploding in of supernovae. ... The new LBV star (Fig.1) is the seventh in M33. ... It is one of the brightest LBV stars of the M33 galaxy. ... The brightest object is the core of the galaxy, - a compact star cluster comprising a supermassive black hole. The new LBV star N93351 is located down and to the left from the core. ...

... 1998, 15, 147­8 . An Imaging Survey of Northern Galactic H Emission with Arcminute Resolution Brian Dennison, John H. Simonetti and Gregory A. Topasna Martin Observatory, Institute for Particle Physics and Astrophysics, Physics Department, Virginia Tech, Blacksburg, VA 24061, USA dennison@astro.phys.vt.edu; jhs@vt.edu; topasna@astro.phys.vt.edu Abstract: We present preliminary results from a high-resolution, high-sensitivity imaging survey of the northern galactic H emission. ...

... This meteor shower, which reaches a peak of up to 120 meteors per hour, as seen from a clear, dark site, can be observed anytime after about 10.00pm for a few nights either side of the maximum, that is from about the 12 to 16 December. The Geminid meteors, which sometimes appear as brightly coloured relatively slow-moving fireballs, are caused by small particles mostly about the size of marbles or smaller, ejected into space from the surface of the near-Earth asteroid Phaethon . ... NASA Site . ...

... Using the DRAO Synthesis Telescope (Landecker et al. 2000), the Canadian Galactic Plane Survey ( CGPS ; Taylor et al. 2002) has captured a multitude of HISA features, the majority of which are invisible in prior surveys at lower resolution. ... Since the HISA gas temperature must be less than the background brightness temperature, all the H I shown in this poster has T ~ 100 K. Figure 1 provides panoramic views of the cold H I visible as HISA in the CGPS. ... GIFs: HISA + CO | HISA only | ...

To appear in "Fourth Workshop on Robotic Autonomous Observatories (2015)"RevMexAA(SC) METEOR OBSERVATIONS WITH MINI-MEGATORTORA WIDE-FIELD MONITORING SYSTEM S. Karpov, 1, 3 N. Orekhova2 G. Beskin, 1, 3 A. Biryukov3,4 S. Bondar,2 E. Ivanov,2 E. Katkova,2 A. Perkov, and V. Sasyuk3 RESUMEN 2 Favor de prop orcionar un resumen en espanol. ... The faintest detected meteors has the peak brightness about 10 mag, while the ma jority - from 4 to 8 mag. ... 2010; Karpov et al. 2013; Beskin et al. ...

Supernova 2000cl in NGC 3318 This page is devoted to information on Supernova 2000cl in NGC 3318 Basic information on this SN, including the last reported brightness, on this Supernova can be found on the main page . Information on the original web pages for many of these images can be found on the Supernova links web page. ... Robin Chassagne's Supernova in NGC 3318 web page in French [ Translate ] . ... Robin Chassagne image . ... and Lidman image . ... vsnet-alert 4896 ] SN 2000cl in NGC 3318 . ...

... The awsome spectacle of a brilliant comet, with its long ghostly tail streaming behind it, is a rare event. ... Only one other comet, Comet Halley, was seen so far from the Sun, giving scientists an opportunity to watch it as it slowly warmed up and sprouted a tail. ... Comets are the Rip Van Winkles of the solar system -- mini-worlds that have changed little during their 4.5-billion-year nap far from the Sun. ... Observing Comets . ... Once, comets inhabited the entire solar system. ...

Astronotes Armagh Planetarium's Stellar Blog! ... Space Flight . ... Earth Satellites . ... Leonid meteors seen from 13 km altitude aboard an aircraft during the 1999 Leonids Multi-Instrument Aircraft Campaign (Leonid-MAC). Comet Tempel-Tuttle provides the cometary debris for the Leonid meteor shower. ... Every 17-19 November Earth crosses Tempel-TuttleтАЩs orbit and the Leonids become visible. With clear, dark skies observers may see 10 to 15 Leonid meteors every hour on those mornings. ...

This all-sky image shows the spatial distribution over the whole sky of the galactic haze at 30 and 44 GHz, extracted from the Planck observations. In addition to this component, other foreground components such as charged particles accelerated radially, known as synchrotron radiation, thermal dust, spinning dust, and extragalactic point sources contribute to the total emission detected by Planck at these frequencies. ... ESA/Planck Collaboration ...