... Archives . ... If you do not mind the time predictor, it is hard to believe that this is a light curve, time dependent data. ... It?s hard to say this data set is designed for time series analysis apart from the complication in statistical inference due to measurement errors. How to design the statistical study with measurement errors, huge gaps in time, and unequal time intervals is complex and unexplored. ... The following is R output without measurement errors. ... Chandra Blog . ...

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 concerns here are similar to those for observing bright targets; saturation and blooming of the bright companion PSF must not impact the faint target. Also, one may need to consider subtracting the PSF of the bright object, and effects which limit the accuracy of that subtraction. If the bright companion will saturate and bloom, it will be necessary to rotate the CCD so that blooming along the CCD columns does not obliterate the faint target. ...

... SEARCH ASP SITE: Match ALL words Match ANY word . ... ASP Conference Series . ... Accidental Astrophysics: The Devil's In the Magnitudes, Part II . ... The star second to the Sun in brilliance is Sirius. ... Recall the magnitude system, passed down to us through a hundred generations of sky watchers, as a means of quantifying stellar brightness ("Accidental Astrophysics," May/June, p. 9). ... Yes, it is a magnitude difference, but that difference is due to the distance between us and the star. ...

... Computing the area lost to bright pixels declared on-board is another matter. It depends on energy, through the bright pixel level. If the telescope's attitude were to vary significantly (more than the PSF) with time, then it should be considered using X,Y (attitude corrected) as coordinates for CCDBKG, since the optical background from stars would follow the attitude variations. ... The subroutines CTI_CORR and ENERGY only call the CAL routines CAL_mosCTIcorrection and CAL_gainCorrection. ...

... 2002 June 20 . Bright Galaxy M81 . ... Explanation: Big and beautiful spiral galaxy M81 , in the northern constellation Ursa Major , is one of the brightest galaxies visible in the skies of planet Earth. This superbly detailed view reveals its bright nucleus, grand spiral arms and sweeping cosmic dust lanes with a scale comparable to the Milky Way . ... The errant dust lane may be the lingering result of a close encounter between M81 and its smaller companion galaxy, M82 . ... About APOD | ...

... Solar System . ... Stars . ... August . ... A classical nova binary system just before an explosion on the surface of the white dwarf. Classical novas occur in a system where a white dwarf closely orbits a normal, companion star. ... A white dwarf is the inert but still white hot core of a dead star. ... This means if you have a dark enough sky the nova is visible to the naked eye but to pick it out you will need to be very familiar with the dim stars between Delphinus and Sagitta (the Arrow). ...

... News . ... Different faces of Pluto emerging in new images from New Horizons . ... These images, taken by New Horizons Long Range Reconnaissance Imager (LORRI), show four different faces of Pluto as it rotates about its axis with a period of 6.4 days. ... The date of each image, the distance of the New Horizons spacecraft from Pluto, and the number of days until Pluto closest approach are all indicated in the figure. ... Only registered members of Astronomy.com are allowed to comment on this article...

... References: %observed energy levels: Johansson L., Magnusson C.E., Joelsson I., Zetterberg P.O., Physica Scripta 46, 221, 1992 %theoretical energy levels: Tayal S.S., Gupta G.P., ApJ 526, 544, 1999 %comment Level ordering is from Tayal Gupta. %comment: Note that Tayal Gupta do not include the 3F and 1F terms from the 3p.4d configuration in their S III model. Produced as part of the Arcetri/Cambridge/NRL 'CHIANTI' atomic data base collaboration % % P.R. Young, Dec-99 . ...

... The ancient chronical said about the colour rings around the Sun and the Moon, about three suns in the sky, light columns, bright lightning, different "comets" rushing to the Earth, moving among the stars or round the Earth with the sky. All these occurrences may be divided into three categories: one that occur in the near or far space, processes going on in the Earth atmosphere under the influence of cosmic factors and at last the occurrences connected with the Earth atmosphere. ... Rainbow . ...

A1446 2000-May-29 23:25:55 Technical Page Proposal Type: Regular General Category: Astronomy Sub-Category: Spectroscopy Observation Category: Extragalactic Total Time Requested: 138 Hours Proposal Title: 21cm Survey of Low Surface Brightness Galaxies Found in the KISS Fields ABSTRACT: Historically, galaxy catalogs have been biased in favor of high surface brightness galaxies. ... This proposal requires coordination with GPS L3 at 1381 MHz. ...