Next: Nonlinearity Up: Special problems Previous: Special problems . Because a full set of colors is required to account for color terms, it is not possible to reduce data for stars that have not been observed in all filters. If you have some stars that were observed in only a subset of bands, you should extract from the entire table of observations just the subset of bands, and run the whole set of stars in this band subset to obtain reduced values for the stars with incomplete observations. ...

Persistence ============================ Observed Effect and Relevant Physics: --------------------------------------- Image persistence is effect of the observed flux of previous images impacting the following observations as an elevated dark current (see Figure 1). ... The amount of charge captured is dependent upon the charge accumulated on the pixel and the amount of time the pixel is subject to this flux. The amount of persistence is also observed to vary between pixels and various arrays. ...

Duty astronomers at the Compact Array are rostered from ATNF staff and students to provide support to observers at Narrabri for periods of one week at a time. The duty astronomers are required to assist observers prepare observing schedules, help set up the Compact Array at the start of an observing run, diagnose and attempt to solve problems that arise in the course of the observations and help observers with the initial analysis of their data. ... www.atnf.csiro.au/observers/tidbinbilla . ...

... 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. ...

P1639 2002-Feb-01 16:28:27 Technical Page Proposal Type: Regular General Category: Pulsars Observation Category: Total Time Requested: 69 Hours Proposal Title: Conal Beam Rotation and the Problems of Nulling, Drifting and Mode Changing ABSTRACT: We request time for pulse-sequence polarimetry of a group of some 50 pulsars, which have received little study at all or little study within the last decade. Most of the pulsars will be observed at 430 MHz, though a few require di erent frequencies. ...

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The problem of solar wind data correlation for the observations onboard several spacecraft is very important for three points of view: . ... This problem is studied now in detail by systematic determination of ion flux and ion velocity data correlations by INTERBALL-1 (IKI group), WIND and IMP 8 (both - MIT group). ... Solar wind plasma correlation lengths from IMP 8, WIND and INTERBALL-1. ... Correlation of solar wind observations onboard several spacecraft: INTERBALL-1, IMP 8 and WIND data. ...

... Revolution : . ... XMM-Newton SOC Home Page Conferences & Meetings . ... General User Support XMM-Newton Helpdesk Users Group . ... 0.0 . ... Cameras closed/off because of Solar flare . ... Cameras in cal-closed because of Leonids . ... X-Ray cameras off because of Solar Flare . ... All Cameras Engineering/Calclosed (Solar Flare) . ... Cameras closed/off because of Solar flare (Started in rev 349) . ... Cameras closed/off because of solar flares . ... Cameras closed/off because of 4WD implementation...

... Calibration and analysis of this observation posed very interesting challenges for the authors, in particular dealing with an exciting new instrument whose on-orbit calibration was not yet well defined. ... Five mosaic positions were observed during five consecutive orbits as well as observations for dark and flat calibration. ... Darks and flats had to be created from contemporaneous reference observations and problems within the calibration process had to be resolved. ...

Text of these problems is available also in other languages : . ... What can one see in the Moon's sky more often - the Sun or the Earth? ... There are about of 250 millions of stars in the elliptical galaxy M32 (a satellite of Andromeda galaxy). ... The masses of Capella's components. ... You are proposed to estimate the masses of Capella's components, using our observational data. ... A galaxy's mass. ... Estimate the mass of FGC 1908 and compare it to the mass of our galaxy. ...

Next: NICMOS/HST H-band (F160W) Images Up: NICMOS Science Previous: HST NICMOS Observations of . ... Observations of P . ... The NICMOS team has devised a comprehensive program of observations of the Galactic Center. ... Data in hand give a first look at variability and a detailed look at the search for the tip of the main sequence will be discussed where NICMOS has demonstrated adequate sensitivity and photometric precision to identify likely O8-B1 stars at the Galactic Center. ...

... Simple X-ray Aperture Photometry Problem : Determine source intensity s and errors for an unresolved (point) x-ray source Know: · Number of counts , C, in source aperture (solid green ellipse) · Number of counts , B, in background aperture (dashed green elliptical annulus) · Areas As and Ab of source and background apertures · f = psf(x,y)dx dy over source aperture · g = psf(x,y)dx dy over background ... What happens if the single observation pdf 's are distinct? ...

Next: Model of clusters Up: paper2 Previous: paper2 . ... It allows estimating different microphysical properties of scatterers (size, complex refractive index, shape, etc.) from measured characteristics of the scattered radiation. ... The complexity of the direct problem depends on its input parameters characterizing the shape, size and structure of the scattering particle. ... Next: Model of clusters Up: paper2 Previous: paper2 root 2003-04-11 ...

... December 21, 1997 . ... Advantages are briefly discussed of gaining in spectral resolution, which is accompanied by losses in signal level, as compared with the attempts to improve the accuracy of measurement of line parameters by means of rising the S/N ratio alone with increasing the exposure time. To partially solve the problem of observations of faint objects at the BTA a new design echelle spectrometer is proposed. high resolution spectroscopy . ...

Next: Case Study Two: The Up: Case Study 1: The Previous: Benefits of the Exercise . Preparation time. ... An intermediate deadline, with students required to show evidence that they've started serious work on this exercise, might solve this problem. ... This problem was resolved by allowing time in lectures and tutorials to discuss the assignment. 14% of students commented that they would have liked more observations, and two students felt that the exercise was too difficult and baffling. ...

... Advises . Contact Advises . As an advise for amateurs we would like to underline: if it's possible, try to observe 3 asteroid positions per night and do not neglect to observe the Numbered Minor Planets in your telescope field of view as a "by product" of your observational programs. ... We think such estimations ought to be produced every morning after CCD observations of the moving celestial objects by observer himself. ...

... 8, ``Celestial Mechanics'', 2002 Dynamics of the Saturnian system with regard to high precision observations A. Vienne 1;2 , W. Thuillot 1 , J. E. Arlot 1 1 IMCCE/Observatoire de Paris 2 Universit'e de Lille, France The acquisition of high precision astrometric observations of Solar System ob­ jects can be applied to the improvement of the dynamical models and to explore some specific problems of celestial mechanics. ... Vienne A., Duriez L. TASS1.6: Ephemerides of the major Saturnian satel­ lites. ...

So the evidence for Dark Matter is fairly overwhelming. ... Theory: if the Universe is closed then all the luminous matter seen in galaxies contributes only 0.5% of the mass required to eventually halt the expansion . ... This means that galaxies are surrounded by dark matter halos which trapped baryonic gas (e.g. hydrogen) and turned it into stars. ... WIMPS - weakly interacting massive particles created in the extremely early universe . ... Theory 99% of the Universe is Dark Matter . ...

... Mosaicing may be used in aperture synthesis to map large fields of view. ... A CLEAN-based method has been developed, in which the components are located in a modified expression. ... Mosaics . ... We present here a CLEAN-based method for the mosaic deconvolution. ... This is a basic problem in mosaic deconvolution: if we intend to apply CLEAN on , the risk of taking a noise peak as a CLEAN component is too important. ... A new CLEAN-based algorithm for mosaic deconvolution has been developed. ...

Next: GOCG Pre-Observation Products . Previous: RadioAstron Mission Element Overview . ... Observation Summary File (OSF) . GRT (Ground Radio Telescope) Schedule Files . ... How: The long-term schedulers will produce two files: GSTS-file (General Space Telescope Schedule) to be used by GOCG and LTS-file for all mission elements. ... What: The RSOG will produce schedule files for all GRTs participating in a particular observation, in the format required by each GRT. ...