... 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 . ...

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. ...

... 2002 March 7 . Comet Ikeya-Zhang Brightens . ... Explanation: In the last week , Comet Ikeya-Zhang has become bright enough to be just visible to the unaided eye. Based on its present activity, observers are optimistic that Ikeya-Zhang will become substantially brighter. This composite color image from March 3rd, captured with a wide-field telescope, shows this active comet's bright, condensed coma and a delightful array of subtle structures in its developing tail. ... About APOD | ...

Next: Historical Background Up: R Coronae Borealis Stars Previous: R Coronae Borealis Stars . R Coronae Borealis stars, or RCB stars, are an important class of VARIABLE STAR . ... RCB stars, remarkably, do both. RCB stars are best known because of their irregular `fades'. ... The fades are caused by enormous clouds of dust which cover a large part of the star's surface. ... As well as irregular fades, the light output from RCBs goes up and down by a few per cent every 40 days or so. ...

... What are the fluxes of the stars? ... Volume sampled is no longer 4/3 pi r cubed due to curved space-time Want to derive population properties brightness, size, etc - as function of distance (therefore, cosmic time) But - biases in sample Biases NUMBER OF STARS VS MASS Eddington Bias: in astronomy, there are always more little faint things than big bright things. ... Suppose there are 10 stars of mass 0.5 and 100 stars of mass 0.4, and you have a 20 percent error on measuring the mass. ...

XMM-Newton Science Analysis System . ... A different approach is done via the setting withctisrcpos =Y: all event energy corrections do not use the actual RAWY coordinate but the corresponding RAWY location of the source ( SRCPOS ) as determined by the task epframes (either automatically or via setting withsrccoords =Y). ... The task epchain may be used with the setting ccds =4 withctisrcpos =Y to process only the CCD 4 where usually the bright source is located that causes the Out-of-Time events. ...

... The two plots below illustrate two of the selection criteria: velocity width (limited by the channel width) and the HIPASS peak flux. Zoom-in on Figure 3a. The two plots below give some idea of the shape of the HI spectra. ... For Gaussian HI spectra the difference is slightly more, but for irrgeular galaxies, pairs and groups many different shapes are observed. ... Some trend towards detecting more narrow-width galaxies at higher velocities is visible. ...

... Albireo: A Bright and Beautiful Double . ... Such is the case of the bright double star Albireo . Seen at even slight magnification, Albireo unfolds from a bright single point into a beautiful double star of strikingly different colors. ... The brighter yellow star is itself a binary star system, but too close together to be resolved even with a telescope. ... Публикации с ключевыми словами: star system - двойные звезды . Публикации со словами: star system - двойные звезды . ...

Next: Background Correction Up: Reduction using Standard Previous: Order definition: Method . The parameter WIDTH2 is the width of the calibration lines. ... Now we can execute CALIBRATE/ECHELLE . ... CALIBRATE/ECHELLE DONE ! ... The user is prompted for the identification of two calibration lines on the image display, repeated in overlapped regions of adjacent orders. ... The wavelength calibration is wrong and apparently no identification error was made: There are too many lines per order. ...

... The J, H and K bands are characterized by a bright background, such a background is mainly due to the emission of atmospheric lines and of thermal radiation. ... If the source cover a large fraction of the slit, spectra off-source must be observed to adequately sample the sky background. ... The on chip integration time (time spent in each position of the slit) must not exceed 40 seconds in J and H bands and 60 seconds in K band. ... We suggest a sequence of 10 for each elementary integration time. ...

Two major reasons: the number of stars isn't really seven (it's many more), and they all have different brightnesses, so that you see more or fewer of them depending on viewing conditions. The brightness of stars is measured on the magnitude scale, where the most prominent stars in the sky are around 1st magnitude, and the faintest you can see with your eye are about 6th. ... I think this makes it quite likely that the list will be truncated at Taygeta, giving six visible stars. ...

. Please standby and you will be automatically connected to the new location of the unframed Supernova page. Or, click on the link above. If you have questions or problems, please email me at David Bishop dbishop@vhdl.org . Last modified: Mon Aug 27 12:40:15 EDT 2001

... This paper describes the main algorithms used by the Einstein Level One processing to create the exposure masks and the background maps for Einstein IPC images, and how these algorithms were recreated in the IRAF environment. Our goal was to recreate the algorithms used by the Level One Processing to create exposure masks and background maps for Einstein Image Proportional Counter (IPC) data (cf. sections 2.5 and 2.7 of Harnden et al. ...

... It is found that the correlation coefficients between these two parameters calculated separately inside and outside the sunspot formation zone ±30 have cyclic variation and occur in anti-phase. This suggests different mechanisms of formation of the corona in the fields of small, medium, and large scales. ... The relationship between the coronal green line brightness (CGLB) and the magnetic field strength (MFS) has been investigated by constructing the corresponding synoptic maps for the 1977-2001. ...

... Bad Astronomy . ... Bad Astronomy: The North Star, Polaris, is a very bright star. Good Astronomy: Polaris is a middling-bright star, easily missed. ... He said it was close to Polaris, the North Star, but he also said it was in the East. ... It's natural, I suppose, to think that such an important star should be bright, but really, that's a conceit, like thinking that the Earth is at the center of the Universe. If more people knew just why Polaris is the North Star, this Bad Idea would stop. ...

... Now, think about a much bigger move: What do you think it would be like if the Earth moved to a different part of our Galaxy? Our Galaxy, the Milky Way, is shaped like a whirlpool: It has bands of stars that spiral around the centre, which astronomers call the Galaxy s arms . ... We live in the outer parts of the Milky Way, in one of its spiral arms. ... The small centre of the Milky Way is a much more crowded place, as this is where most of its stars are found. ...

... 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. ...

... 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 . ...

Images and text 2003 Paul Valleli . While up at Stellafane for pre-convention preparations, I spent some early morning times, experimenting with different videography setups on the 13" F/10 Schupmann at the McGregor Observatory. ... Mars was too bright and would have required neutral density filters. ... Next time, I will try 12mm and 9mm projections. ... I aquired about ten thousand frames by 3AM, at which time a breeze picked up and the seeing went to Hellas! ... 2003 Paul Valleli . ...

... Dept. for Astrometry & Space Geodynamics . ... Dept. for Physics of Stars&Galaxies . ... Dept. for Physics of Planetary Systems . ... Science . ... All Pages . ... Research of the stars with planets which pass apparent star disk (transiting exoplanets). The transit method based on a detection star brightness decrease during a passing of planet in front of its disk. Observed brightness system decries when planet pass star disk and its volume depend of the relative sizes star and planet. ...