A team of U.S. and German astrophysicists have made the first ever detection of X-rays coming from a comet. ... Following the initial detection, the team reported repeated X-ray emissions from the comet over the next 24 hours. ... One preliminary theory is that X-ray emission from the Sun was absorbed by a cloud of gaseous water molecules surrounding the nucleus of the comet, and then were re-emitted by the molecules in a process physicists call "fluorescence." ... Comets . ...

... Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer. April 11, 1996 . Unexpected X-rays from Comet Hyakutake . Credit: C. Lisse, M. Mumma (NASA/GSFC), K. Dennerl, J. Schmidt, and J. Englhauser (MPE) . Explanation: The first X-rays ever detected from a comet were discovered from Comet Hyakutake with the ROSAT satellite on March 27th. ... About APOD | ... A service of: LHEA at NASA / GSFC . ...

... Unexpected X-rays from Comet Hyakutake . ... 11.04.1996 . ... Credit Copyright: C. Lisse, M. Mumma (NASA/GSFC), K. Dennerl, J. Schmidt, and J. Englhauser (MPE) Explanation: The first X-rays ever detected from a comet were discovered from Comet Hyakutake with the ROSAT satellite on March 27th. ... One possible explanation is that X-rays emitted from the Sun are absorbed by water in the comet's coma causing fluorescence. ... Information: The Scale of the Universe Debate in April 1996 . ... April 1996 ...

Supernova 2009js in NGC 918 . This page is devoted to information on Supernova 2009js in NGC 918 . 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 updates and links web pages. Discovered independently by Lick Observatory Supernova Search (USA) and Koichi Itagaki (Japan). ... 2009/10/11.44 . 17.2 . ... Joseph Brimacombe . ...

Here we report our discovery of a band of blue luminescence (BL) in the Red Rectangle nebula. ... The spectrum of this newly discovered BL is most likely fluorescence from small neutral polycyclic aromatic hydrocarbon (PAH) molecules. ... If the carriers of this near-UV/blue fluorescence are PAHs, they are most likely neutral PAH molecules consisting of three to four aromatic rings such as anthracene (C14H10) and pyrene (C16H10). ...

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. ...

Detected Supernovae . The search have produced till now the detections of 4 SNe. ... This result highlights the power of infrared monitoring in detecting Obscured SNe and indicates that optical surveys are probably missing a significant fraction of SNe, especially in obscured systems such as starburst galaxies. ... In Fig. we show the archival SOFI image of NGC3256 (left) and the first image obtained in 2001 (right) where SN2001db has been detected. ...

... Another piece of asteroid discovery news, from Terry Moseley: "Dave Grennan from Dublin has just discovered a Main Belt asteroid from his observatory in Raheny. ... Dave's discovery comes just after Dave McDonald's find of 2008 TM9 a few weeks ago. ... This is only the third asteroid ever discovered in Ireland. ... This has been an amazing year for astronomy in Ireland, and is a superb lead-in to IYA 2009!" ... International Year of Astronomy, Ireland National Node . ...

Astronotes Armagh Planetarium's Stellar Blog! ... Planets . ... Our Galaxy . ... Weird and Fun . ... It came from another galaxy: This artistтАЩs impression shows HIP 13044 b, an exoplanet orbiting a star that entered our galaxy from beyond. ... HIP 13044 is one of tens of millions of stars in the тАЬHelmi streamтАЭ, stars that belonged to a dwarf galaxy consumed by our own Milky Way galaxy, some six to nine billion years ago. ... Tweets that mention ESO finds weird doomed planet from another galaxy | ...

Circularly polarized emission from the transient bursting radio source GCRT J1745-3009: Emission from magnetized dw arf ? ... Size < 8.R. Brightness temperature >1010 K for distance >1 pc, and circular poln. rules out thermal and incoherent synchrotron emission. ... Flare stars (typically dwarf stars of class G to M) in the Galaxy could emit strong high Cir. Pol. radio emission. ... Comparison with flare star Cir. ... GCRT could be outbursts from a highly subsolar flare star with a distance 4 kpc. ...

... The Galactic low-mass X-ray binary GS 2023+338 was discovered during the burst on May 22, 1989 with the Japanise satellite Ginga (aka Galaxy). The flux reached 17 crabs (this unit of flux measurement is an bright X-ray source, Crab Nebula) at 10-35 keV. ... No other radio telescope worldwide carried out multi-frequency measurements. ... Upon 14 days the radio flux fell below the detection level at the RATAN-600 in relation to the decrease of the X-ray flux. ...

... Animation of the neutral hydrogen data cube from Westerbork. ... VIRGOHI 21 was a dark galaxy candidate discovered in 2005 it was found to contain no starlight down to a very low surface-brightness level, yet its velocity structure implied that it had a mass of 10 10 10 11 solar masses. ... VIRGOHI 21 was first observed in the 21-cm line of neutral hydrogen with the Lovell telescope at Jodrell Bank Observatory and the detection was confirmed using the Arecibo telescope ( Davies et al. ...

... The SN 1998bv discovered on April 6, 1998 in the blue compact galaxy HS 1035+4758 is the second supernova observed in a low-mass galaxy with intense SF burst. ... According to its characteristic spectrum, SN 1998bv is a type II supernova with estimated peak absolute brightness M 16.3. The very slow fading of its brightness suggests that the SN was discovered at the Plateau phase, 20-30 days after the peak of the light curve. The most probable classification of SN 1998bv is regular SN II-P. 3. ...

... A tussle in the distant Universe. This Hubble Space Telescope image shows evidence for a merger between a quasar and a companion galaxy. The quasar is the bright object just beneath the image center, and the wisps of material around it are remains of a galaxy disrupted by the interaction between it and the quasar. ... Galactic Nuclei: Old Quasars? Quasars as Probes of the Distant Universe . ... Quasars. ... The name quasar is made up with parts of the words "quasi-stellar radio." ...

... MASTER Net is 56 square degrees per 1 exposition . ... 06 Dec 2015: GRB 151205B: MASTER-NET early optical observations GCN18665 . ... 18 Nov 2015: GRB 151118A: MASTER-NET optical observations GCN18613 . ... 12 Nov 2015: GRB 151112A: MASTER-NET optical limit GCN18591 . ... 07 Nov 2015: GRB 151107A: MASTER-NET optical observations GCN18565 . ... 31 Oct 2015: Five OTs detected by Global Robotic MASTER Net ATel8232 . ... 02 Oct 2015: GRB 151001B: MASTER-NET early optical observations GCN18380 . ...

Check out the new images (Jan 18-25) and (Jan 26-Feb 05) of the comet by Rob McNaught. ... Every few years a comet becomes bright enough to be easily seen with the naked eye but only every decade or so are these comparable with comets like Halley. ... Before Jan 13, the comet is not visible in the Australian sky after sunset. ... SOHO images . ... On Jan 12 at approximately 09:00 UT (8pm NSW time), comet C/2006 P1 McNaught appears at the 11 o'clock position in the images. ... STEREO images . ...

... In the three intervening decades there have been many observations of this diffuse emission over a wide range of x-ray energies. ... During the 1970's researchers at the University of Wisconsin, lead by Dr. William Kraushaar, used a series of sounding rocket flights to map the diffuse x-ray emission from the sky in several bands. ... University of Wisconsin Sky Survey map of the B-band (0.13-0.188 keV) x-ray intensity. ... University of Wisconsin Sky Survey map of the 2-6 keV band x-ray intensity. ...

... Survey Telescopes . ... Galaxy Clusters . ... Based on exciting new data obtained with the ROSAT X-ray satellite and a ground-based telescope at the ESO La Silla Observatory, a team of European astronomers [2] has just discovered a very distant cluster of galaxies with unique properties. It emits the strongest X-ray emission of any cluster ever observed by ROSAT and is accompanied by two extraordinarily luminous arcs that represent the gravitationally deflected images of even more distant objects. ...

... Tonight's Sky . ... An artificial comet holds secrets to Earths life . ... Tune into the Asteroid Day press conference . ... Catalina Sky Survey discovers possible extinct comet . ... An asteroid discovered more than 100 years ago may not be an asteroid at all, but an extinct comet that is coming back to life, according to new observations. ... In 1998, Larson founded the Catalina Sky Survey, a NASA-supported project to discover and catalog Earth-approaching and potentially hazardous asteroids. ...

... On January 1, 1925, thirty-five-year-old Edwin Hubble announced findings that ultimately established that our universe was a thousand trillion times larger than previously believed, filled with myriad galaxies like our own. ... Six years later, continuing research by Hubble and others forced Albert Einstein to renounce his own cosmic model and finally accept the astonishing fact that the universe was not immobile but instead expanding. ... Copyright (c) Amateur Telescope Makers of Boston, Inc. ...