... 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. ...

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. ...

... Inside the Eagle Nebula . ... A closer look at the Eagle Nebula, however, shows the bright region is actually a window into the center of a larger dark shell of dust. ... In September 1967, during regular season play, the Surveyor 5 lander actually slid several feet while making a successful soft landing on the Moon's Mare Tranquillitatis. ... This third quarter Moon (left) and first quarter Moon were both photographed during the last lunar cycle or lunation with the same telescope and camera. ...

... From the data taken during Cycle 1, surface brightness profiles have been obtained for 13 globular clusters in M31 (Fusi Pecci et al. 1993), leading also to the detection of a central cusp in a candidate post-core-collapse cluster (Bendinelli et al. ... Surface brightness profiles obtained with VISTA. ... PSF 512 512, data matrix smaller and smaller (256 256, 128 128, 64 64), sky = 0, RMG (Fig. 3b): the derived profiles remain unaffected a part from the reduction in radial extension. ...

... STScI-PRC96-25 HUBBLE'S 100,000TH EXPOSURE CAPTURES IMAGE OF DISTANT QUASAR The Hubble Space Telescope achieved its 100,000th exposure June 22 with a snapshot of a quasar that is about 9 billion light-years from Earth. ... The fainter object just above it is an elliptical galaxy. ... The quasar and star are separated by billions of light-years. ... Image files in GIF and JPEG format and captions may be accessed on Internet via anonymous ftp from ftp.stsci.edu in /pubinfo. ...

Compilation of Surface Brightness . HyperLeda home | Documentation | Search by name | ... Search an object in the surface brightness catalogue . The surface brightness in magnitudes per square arcsec (mag arcsec -2 ) . ... Surface brightness at effective radius . ... Effective mean surface brightness within the effective radius (equivalent radius in which half the total flux is emitted). ... Quality Flag The quality flag has the following meaning: . ... regular measurement . ...

... Data It is now clear that fuzzballs are actually galaxies. ... Using the automatic telescope, we measured the redshifts and brightnesses of a large number of fuzzballs in all regions of the sky. ... Correlation between brightness and redshift Redshifts and Brightnesses 0.005 0.004 0.003 0.002 0.001 0 -0.001 0 -0.002 -0.003 -0.004 -0.005 Redshift of Fuzzball 500 1000 1500 2000 Brightness of Fuzzball The brightnesses and redshifts of all the fuzzballs measured are shown in this graph. ...

... Armagh Observatory, College Hill, Armagh BT61 9DG, +44 (0)28 3752 2928 . See also images taken on November 22nd . Image taken by Andy McCrea who says, . To me the comet appears yellowish and it has gone from star-like to a . ... More images from Andy McCrea here . ... The true explanation is that a very faint comet, known as periodic comet Holmes, produced a massive outburst of material and became a million times brighter than it was just a day earlier. ... More images from Andy McCrea . ...

In autumn 1994, two groups of astronomers announced that they had discovered Cepheid variable stars in a distant cluster of galaxies. ... As the term suggests, variable stars change in brightness over time. ... Variable stars are an ideal way to get high-school students doing real science, with real data, from the real sky. ... a sky chart to find the stars . ... Students can use the nearby stars to estimate the magnitude of Delta. ... Locate the star Delta in Cepheus and estimate its brightness . ...

... 2005 June 21 . The Cygnus Wall of Star Formation . ... Explanation: The North America Nebula in the sky can do what North Americans on Earth cannot -- form stars. Specifically, in analogy to the Earth-confined continent , the bright part that appears as Central America and Mexico is actually a hot bed of gas, dust, and newly formed stars known as the Cygnus Wall . ... About APOD | ... NASA Web Site Statements, Warnings, and Disclaimers . NASA Official: Jay Norris. ...

Proceedings of Turbulent Shear Flows XI , 1997. NASA Technical Paper # 3555 , 1997. Proceedings of European Turbulence Conference VI , 1996. ESPRI Research Report # 104, 117-143 (1996) . ... Proceedings of Turbulent Shear Flows X , 1995. ASME Paper 95-GT-437 , 1995. ... Invited AIAA Paper 94-2281 presented at the 1994 AIAA Fluid Dynamics Conference, Colorado Springs, CO. AIAA Paper 94-2323, presented at the 1994 AIAA Fluid Dynamics Conference, Colorado Springs, CO. ...

... The Pleiades star cluster, also known as the Seven Sisters and Messier 45, is a conspicuous object in the night sky with a prominent place in ancient mythology . ... The stars in the Pleiades are thought to have formed together around 100 million years ago, making them 1/50th the age of our sun, and they lie some 130 parsecs (425 light years ) away. ... Data for these stars are listed in a table below. ... Yes . ... WEBDA Pleiades cluster data . ... M45: The Pleiades Star Cluster (2007 November 18) ...

Umbriel . Uranus II . Umbriel [UM-bree-ul] is the darkest satellite of Uranus. It is about the same size as Ariel and has about the same density. The surface appears to be old with large craters and does not change much from one location to another. Near the top is a puzzling bright ring called the fluorescent cheerio . ... Dark regions are represented as red and bright regions are represented as blue. The two white regions are bright ejecta from two fresh craters. ...

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. ...

... Energy . ... Solar Wind . ... Field . ... 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. For some reason the field slows down the flow of heat from the Sun's interior and keeps sunspots slightly cooler than their surroundings. ... Solar Eclipses . ...

The Low Surface Brightness Galaxy HIPASS1126­72 Virginia Kilborn 1 , Erwin de Blok 1 , Lister Staveley­Smith 2 , Rachel Webster 1 1. ... The low surface brightness galaxy HIPASS1126­72 was de­ tected in the HI Parkes All Sky Survey (HIPASS). ... This galaxy represents a class of galaxies that we will readily detect in the HIPASS survey, which have low surface brightness in the optical, but are easily detectable in neutral hydrogen. ... The velocity profile from HIPASS can be seen in Figure 1(a). ...

. This illustration provides a comparison for how big the moons of Mars appear to be, as seen from the surface of Mars, in relation to the size that Earth's moon appears to be when seen from the surface of Earth. Earth's moon actually has a diameter more than 100 times greater than the larger martian moon, Phobos. However, the martian moons orbit much closer to their planet than the distance between Earth and Earth's moon. // NASA/JPL-Caltech/Malin Space Science Systems/Texas A Univ.

Seven months ago, on Mar 19, 2008, at 09:12 Moscow time, a new star appeared on the sky. The Sun had already risen over the Russia, but people of the Western hemisphere might be able to see by their eyes a faint starlet near one of Bootes constellation stars. This starlet appeared and faded by an order of magnitude in a minute. Astronomers named it GRB080319B or, informally, the Naked-Eye Burst, as it was twice as bright as human eye can see a star. ... Royal Astronomical Society . ...

You Can Make Stellar Images Brighter . Articles | ... A few months ago I wrote an article titled "You Can’t Make Them Brighter". So why am I now writing that you can make them brighter. ... The image of a focused star is actually a small disk called the Airy disk, named after the 19 th century scientist Sir George Airy. ... For a given aperture, a smaller Airy disk means that the light is focused to a smaller disk and is therefore brighter. ... www.astronomy.net . About Astronomy Net | ...

... This beautiful new image shows a glowing cloud of cosmic dust sitting boldly against a backdrop of shining stars. To the naked eye, thick clouds like these appear empty and dark, but some are actually home to the brightest nebulae and hottest young stars in the Universe! Stars are made of gas, so it is no surprise that they are born inside thick, gassy clouds. But the clouds that give birth to stars also block our view of them growing within. ...