... 21.03.1998 . ... Credit Copyright: National Solar Observatory Explanation: Our Sun has spots! These spots appear dark in photographs like the one above, but in fact sunspots are quite bright - they are just dark compared to the rest of the Sun. ... Sunspots occur when a concentrated portion of the Solar magnetic field pokes through the surface. ... The Sun and sunspots should never be looked at directly . ... Publications with keywords: Sun - sunspot . Publications with words: Sun - sunspot . ...

... January 13, 1997 . Sunspots: Magnetic Depressions . ... Explanation : Our Sun has spots! These spots appear dark in photographs like the one above, but in fact sunspots are quite bright - they are just dark compared to the rest of the Sun. ... This field slows energy from entering the sunspot region, causing sunspots to appear cooler, darker, and lower than the surrounding surface. ... The Sun and sunspots should never be looked at directly . ... About APOD > . ...

... 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. ...

... Today this year's largest group of sunspots will cross the Sun's central meridian. ... The next day, the number of spots in the group reached five, and the day after, on June 2nd, it was possible to count thirteen sunspots on solar disk, which had been clear prior to this. ... This year's two most powerful active areas, which passed across the solar disk at the beginning of May, 2009, are set to appear in the Sun's eastern sector in two days, on June 6th. ...

... 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 | ...

home publications > mercury . ... Astronomy Beat . ... Nearly four centuries ago, Galileo's simple observations of Earth's planetary sibling, Venus, buoyed the proponents of a Copernican universe. ... The Italian astronomer had settled into a new house in Florence and had begun to observe Venus, which in November 1610 would have appeared as an evening star, bright in the western sky after dusk. ... From these two observations, Galileo inferred that Venus must orbit closer to the Sun than does Earth. ...

... Circumstellar disc of beta Pictoris: constraints on grain properties from polarization. To appear in the Astronomy & Astrophysics . abs , src , ps ] . ... Dust influx to Titan from Hyperion . ... abs ] . ... Characteristics of bulges and disks in interacting galaxies . ... Dust grains around Herbig Ae/Be stars: porous, cometary-like grains? ... To appear in the Astronomy & Astrophysics Supplement . ... Finally, Links may lead you to more options (e.g. via the LANL preprint system). ...

Astronomy Discussion Forums . ... Atm ћ Astrophotography ћ Blackholes ћ Blackholes2 ћ CCD ћ Celestron ћ Domes ћ Education . ... New Model: How Do The Sun And Moon Appear To Move Across The Sky . ... Post Message | ... focused on the Sun and the Moon as they appear from the given location of the Earth surface: . ... www.astronomy.net . About Astronomy Net | ... Forum posts are Copyright their authors as specified in the heading above the post. "dbHTML," "AstroGuide," "ASTRONOMY.NET" & "VA.NET" . ...

... Star Atlas . ... stars . ... Globular cluster NGC 2808, elliptical galaxy NGC 2986, and the Sextans Dwarf . ... Proxima Centauri is a red dwarf star, so would it appear red from the surface of an Earth-like planet in that star's habitable zone? ... Astronomers haven t found planets around our Sun s nearest neighbor, the red dwarf Proxima Centauri. ... Most exoplanets orbit red dwarfs the most common and longest-lived type of star. ... Get instant access to subscriber content on Astronomy.com! ...

... OOF . ... OOF Index . ... OOF software . ... Fits up to fifth order . ... These are experimental data currently being analysed, not final documentation of research. ... Only fitting for Zernike orders up to and including 3rd to concentrate on finding possible off-axis aberrations. ... The results below show that when fitting for all Zernikes up to and including fifth order, the output maps vary greatly between pixels. As above, but fitting up to fifth order Zernike polynomial. ...

... Kirby, E., Jerjen, H., Ryder, S., Driver, S., Deep Near-IR Surface Photometry of 57 Galaxies in the Local Sphere of Influence , AJ, 136, 1866 (2008) . Kirby, E., Jerjen, H., Ryder, S., Driver, S., 2007, to appear in proceedings of "Galaxies in the Local Volume", Sydney, July 2007 (astro-ph/ 0709.2192 ) Deepest Near-IR Surface Photometry of Galaxies in the Local Sphere of Influence . Kirby, E., Jerjen, H., Ryder, S., Driver, S., The Maximum Baryonic Content of a Galaxy , in preparation . ...

Gerry Doyle's homepage . Watch this space!

... R.S. de Jong, A.C. Seth, D.J. Radburn-Smith, E.F. Bell, T.M. Brown, J.S. Bullock, S. Courteau, J.J. Dalcanton, H.C. Ferguson, P. Goudfrooij, S. Holfeltz, B.W. Holwerda, C. Purcell, J. Sick, D.B. Zucker, 2007, ApJL 667, 49 . ... S.A. Kassin, R.S. de Jong, B.J. Weiner 2005, ApJ 643, 804 . ... I. Near-Infrared and Optical Broadband Surface Photometry of 30 Galaxies . ... Eric F. Bell and Roelof S. de Jong 2001, ApJ 550, 212-229 . ... Roelof S. de Jong 1996, A Suppl. ... Back to Roelof's home page () . ...

Phobos . Mars I . Phobos [FOH-bohs] (fear) is a moon of Mars and was named after an attendant of the Roman war god Mars. ... Phobos shows striated patterns which are probably cracks caused by the impact event of the largest crater on the moon. ... The striking feature in this image is the giant Stickney crater. ... Courtesy NASA) . ... Because Phobos is only 28 by 20 kilometers (17 by 12 miles), the moon must have been nearly shattered from the force of the impact that caused the giant crater. ...

... Z., to appear; 3. ... D. Crowley, S. Ferry, M. Skopenkov, The rational classification of links in codimension > 2, Forum Math., to appear; 6. D. Repov M. Skopenkov, F. Spaggiary, On the Pontryagin­Steenrod­Wu theorem, Israel J.Math. 145 (2005), 341­347; s, 7. M. Cencelj, D. Repov M. Skopenkov, Classification of knotted tori in the 2-metastable dimension, Sbornik Math., to s, appear; 8. ... M. Cencelj, D. Repov M. Skopenkov, Classification of framed links in 3-manifolds, Proc. Indian Acad. ...

... self-absorption - the absorption of light shining on an object by a process similar to that which produced the light originally; if a cloud emits less light than it absorbs from other clouds behind it, this net loss of light, termed self-absorption , causes the foreground cloud to appear darker than the background field (the term is from spectroscopy, where small absorption dips sometimes occur in larger emission lines, making the latter look as if it is absorbing part of itself) . ... HISA Main ...

Our publications in 2007 year Pustilnik, S. A.; Tepliakova, A. L.; Kniazev, A. Y.; Burenkov, A. N.; SAO; Russia; SAAO; Africa, South . eprint arXiv:0712.4205, submitted to Astrophysical Bulletin (SAO) (12/2007) . Pustilnik, S. A.; Tepliakova, A. L.; Kniazev, A. Y. eprint arXiv:0712.4007, submitted to Astron.Lett (12/2007) . ... Kniazev, A. Y.; Pustilnik, S. A.; Zucker, D. B. eprint arXiv:0707.4285, submitted to MNRAS (07/2007) . ... eprint arXiv:0707.4288 (07/2007) . ...

Astronotes Armagh Planetarium's Stellar Blog! ... This image combines orbital imagery with 3-D modelling to show flows that appear in spring and summer on a slope inside Mars' Newton crater. ... Warm season flows on a slope in Newton Crater, possible evidence of salty liquid water active on Mars today. Image credit: NASA) . ... Frozen water is common on and under the surface of Mars but these images are the best evidence to date for the presence of liquid water on the Martian surface today. ...

... Yu.A.Nefyodov, M.R.Trunin, A.F.Shevchun, D.V.Shovkun, N.N.Kolesnikov, M.P.Kulakov, A.Agliolo Gallitto, and S.Fricano, Europhysics Letters 58 (3), 422 (2002) . ... M.R. Trunin, Yu.A. Nefyodov, A.F. Shevchun Phys. Rev. Lett. 92 , 067006 (2004) . ... M.R. Trunin, Yu.A. Nefyodov, A.F. Shevchun, Supercond.Sci. ... V.N. Egorov, V.L. Masalov, Yu.A. Nefyodov, A.F. Shevchun, M.R. Trunin, V.E. Zhitomirsky, and M. McLean. ... Yu.A. Nefyodov, A.F. Shevchun, A.M. Shuvaev, M.R. Trunin . ... Publications . ...

... ATNF Home . About ATNF . ... About ATNF overview . ... Australia Telescope Steering Committee . ... Australia Telescope User Committee . ... Murchison Radio-astronomy Observatory . ... Parkes radio telescope . Australia Telescope Compact Array . Mopra radio telescope . ... Visiting Parkes radio telescope . ... Parkes radio telescope webcam . ... A brief snapshot summary of the Australia Telescope Compact Array surface extension project is presented here. ... Go to MNRF Projects Page . ...