HUBBLE SPACE TELESCOPE DAILY REPORT #843 PERIOD COVERED: 0800 EST Daily Status Report as of 074/1200Z. 1.0 ACTIVITIES SCHEDULED AND ACCOMPLISHED: 1.1 Completed Three Sets of FOS/RD 4698 (FOS Dark Monitoring) The Faint Object Spectrograph was used to take a series of three internal flat exposures to determine the instruments background. All three observations were reported to look as expected. ... The exposure completed without incident under course track using a single guide star. ...

... Laboratory and theoretical modelling of the UV bump on the interstellar extinction curve is a very popular topic in dusty investigations. ... feature is illustrated by Fig. 10 where the profiles were calculated using the model of graphite spheres. Figure 10: Normalized extinction efficiencies for graphite spheres. ... The lower panel shows the summary extinction of two graphite spheres with radii and (from upper panel) taken in equal proportions. ...

This thread illustrates how to evaluate if your RGS observation is affected by pile-up; if so, how to deal with it in some special cases; and how to prevent it occurring. ... Pile-up will cause two coincident first order . ... Thus, pile-up may differ between RGS1 and RGS2 and may abruptly vary between CCD locations due to the nominal event pattern distribution variations over the detectors. ... Migration of photons from 1st to 2nd order (or from 2nd order to 3rd order) . ...

... Team . ... GRB mini-workshop 2006 . ... Our study of GRB fields in optical range efforts to shed light on the progenitor problem and it is naturally splitting into two directions. The first one is study of GRB OT via follow-up observations, while the second way is investigation of GRB host galaxies. ... The first stage consists in observational data acquision, the second one yields estimates of GRB OT characteristics and its host galaxy parameters. ... Do GRB hosts differ from field galaxies? ...

... The predictive power of current models (the so-called meteor forecasting) has given us the exact timing of the Leonid storms of 2001 and 2002 to the nearest hour and are now used to predict the arrival times of major annual showers such as the Perseids . ... Towards this goal, the Observatory has installed a sky-monitoring system, consisting of one medium angle (MA) and two wide-angle (WA) video cameras linked to software designed to detect motion. ... Bright Taurid Meteor . ... Meteors on Mars . ...

... 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. ...

Next: Reduction procedure Up: Extinction and transformation Previous: Strategy . Standard stars can be included in the extinction solution, if one is careful. The problem is that there are usually appreciable ``conformity errors'' due to mismatch between the instrumental and the standard passbands [ 16 ]. ... Thus, it is wrong to assume that the transformation between the instrumental system and the standard system is exact, even if there were no measurement error in either system [ 1 ]. ...

... Up: Data Analysis and Processing Techniques . ... Also, a method for quality control of CCD observations is suggested. ... Everyone who observes a celestial object using a CCD detects moving celestial objects as a ``by product''. ... We hope that our investigations may be useful for near-Earth space control and also for searches of the moving celestial objects through analysis of old and new CCD frames obtained at any amateur or professional astronomical observatory. ...

... Observing . ... The double star 54 Leonis, spiral galaxy NGC 3198, and emission nebula NGC 3199 . ... Problems posed by massive stars . ... These questions were at least part of the motivation when CУЕssio Barbosa of Brazil's University of SУ?o Paulo and Donald Figer of the Space Telescope Science Institute in Baltimore surveyed observers and theorists to see what they believed were the most pressing problems concerning massive stars. ... Get instant access to subscriber content on Astronomy.com! ...

Subject, Problems and Objects of Theoretical Astrophysics. ... Stellar Photospheres, Their Features. ... Physics of Continuous Radiation Absorption in Stellar Photospheres. ... Continuous Radiation Absorption in Stellar Photospheres of Various Spectral Classes. Solar Type Photospheres. ... Characterisics of Absorption Lines. ... Interstellar Absorption Lines, Their Features. ... Physical and Dynamic Features of Interstellar Medium, Which Follows from Observations of Interstellar Absorption Lines. ...

... There is a search machine which is valuable if you have a problem which can be described in terms of a few key words. The technical forums will also describe new facilities as they are brought on-line. CA-forum - compact array technical issues . ... The Narrabri Compact Array documentation . ... Search tool ----- This only covers the epping web site. ... 04-Apr-1997 M.J.L. Kesteven (mkesteve@atnf.csiro.au) . ...

Bigbang Forum Message . Forums: . ... Big Bang | ... PROBLEMS WITH COSMOLOGY? ... I have read about problems with 'Big Bang theory' and Einstein’s relativity theories. ... This was written by a physicist: an enthusiast and expert in string theory! ... It is indeed this problem which Greene (2) shows string theory is set up to solve." ... www.astronomy.net . ... Forum posts are Copyright their authors as specified in the heading above the post. "dbHTML," "AstroGuide," "ASTRONOMY.NET" & "VA.NET" . ...

... 8, ``Celestial Mechanics'', 2002 Parameterization of the Solar Radiation Pressure model for GPS satellites I. S. Gayazov Institute of Applied Astronomy, St. Petersburg, Russia The treatment of solar radiation pressure (SRP) effect until now is the main problem in precise modeling of GPS satellite orbits. ... In practice, however, all seven parameters of the empirical model cannot be confidently determined from phase observations. ... Bar­Sever Y. E. A new model for GPS yaw attitude. ...

... identify a realistic size of an event on the wavelet map; for example, a rectangular box one-duration wide and allowing for limited ratio of durations in height, has been used. identify all local maxima by placing a box around them and verifying that no larger values occur within the box. within each box, normalize the values of the map by the local maximum. threshold what is left to show the vicinity of each maximum. ... Figure 25: Local maxima of g2-energy map. ...

... Seminar archive . ... Type Ia Supernovae (SNe Ia) have an important role to measure a distance to an anonymous galaxy because they have a good correlation of the decline rates of the light curves with the absolute luminosity. ... First, super-Chandrasekhar SNe which have extremely high luminosity, slow decline rate of the light curves, slow expansion velocity and strong carbon features. ... As another example of diversity of SNe Ia, I would like also to introduce Type Iax SNe. ... All seminars: . ...

... Please note the following problems and workarounds: . ... Arrow keys . Arrow keys are used in SAOtng to move the mouse or markers. ... Unfortunately, error messages are generated if both sets are defined in the SAOtng code but are not supported by X. To get around this problem, we have added the -kbprefix command switch (and the SAOTNG_KBPREFIX environment variable) to SAOtng. This switch allows you to specify which arrow keys you want to use (assuming your version of X supports both). ...

... The First (Experimental) International Astronomy Olympiad . The following olympic problems were proposed for the participants on the theoretical part: Grades 8-10 . ... Why is it sometimes better to use a small telescope in orbit around the Earth than it is to use a large telescope on a mountain top? ... What will an observer looking to the Moon through the telescope see? ... Paper with a drown circle and table of maximal elongations of Mercury and Venus had been done for participants. ...

... L-Wide . ... Receiver History . ... Available Filters: . ... Use with e.g. filter 5) NOTE 2 1120-1220 3 1230-1470 4 1550-1820 5 1100-1800 6 1360-1470 7 1320 hipass NOTE 8 1180-1280 9 1280 hipass (ext Output unit. ... Consequently, the calibration for data collected using the hipass 1320 and the hipass 1370 filters only will be mis-calibrated (i.e. by using the opposite polarisation calibration data). ... It is now possible to select any bandpass filter that is not in the 1320 hipass band. ...

... The first step to improve the FORS calibration is therefore to obtain data to allow a computation of the illumination correction across the field. ... Another limitation on the calibration accuracy has been the brightness of the Landolt standards which have forced the use of extremely short exposures introducing small but non-negligible shutter-time errors and also resulting in a very small number of useful standards per frame. ...