... 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 . ...

... 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. ...

... 2.3 Establishing the Extragalactic Distance Scale . ... 2.3.2 The Second Rung: Distances to stellar clusters . ... 2.3.4 Distances to Local Group Galaxies . ... The Luminosity Function of Planetary Nebulae . ... 3.2.2 Clusters of Galaxies . ... 4.2 Evidence for Dark Matter as a Function of Scale Size . ... 4.3 Other Dark Matter Indicators for Galaxies . ... What is the nature of the large-scale distribution of matter in the universe as traced by the three-dimensional galaxy distribution? ...

... Science Users Information > Observing Facilities > La Silla Facilities > La Silla Science Operations . ... La Silla News . ... Internal Pages . La Silla Science Operations Department (LSO) is part of the La Silla Paranal Observatory and is in charge of the operations of the telescopes on La Silla. ... In the La Silla Science Operation pages, you should find all the information you need for your observations from the time you have an idea of observations until when you finish processing your data. ...

GRANAT is the Russian x-ray sattelite launched to the high apogee orbit (200,000 km) and operated almost for 10 years (1989 -1999) , carrying out four major instruments: French SIGMA coded-mask hard x-ray telescope (30-1000 keV), Soviet ART-P coded-mask telescope (2??-60?? keV), all-sky monitor WATCH (6-150 keV), and a gamma-burst detector PHEBUS . ... Since September 1994, GRANAT is in the survey mode. ... Explore pages devoted to individual GRANAT instruments (including main scientific results): . ...

... XMM-Newton SOC Home Page Conferences & Meetings . ... Data Analysis SAS News What is SAS? How to use SAS SAS Workshops SAS Version Changes Download and Install SAS Science Simulator (SciSim) . ... EPIC cameras optical loading . ... The PI is invited to cross-check the expected X-ray flux from the target source (and from any other potentially bright source in the target field of view), or to provide the SOC with her/his own estimate, if not originally specified in the proposal. ...

... The improvement will be more pronounced in our crowded Wide Field Camera (WFC) images, and may be increased further through use of a more sophisticated method of combining the individual dithered images. Our analysis allows us to check for point spread function shape variations in the HST Planetary Camera (PC) field. ... In crowded field images, we are deriving information about the faint end of the luminosity function (LF) from the texture of the image background. ...

... The R , I photometric observations of SBS 0335-052W were obtained occasionally during the study of SBS 0335-052 with the 3.5m telescope in Calar Alto on 1991 October 6. ... Aperture photometry was performed on the standard star observations using MAGNITUDE/CIRCLE task with the same aperture for all stars. ... For photometry of extended objects, we used the package SURFPHOT as well as dedicated software for adaptive filtering developed at the Astrophysical Institute of Potsdam (Lorenz et al. ...

Smithsonian Astrophysical Observatory Memorandum To : From Date: Re: M. Cappi, Strong Gravity SDT/YB Team, XMS team : M. Garcia April 14, 2010 XMS high/mid/low resolution event rates for bright AGN mrg-2010-02v2 This memo arises out of the concern that the bright AGN that will be used to observed strong gravity effects ­ in particular those for which time-resolved measurements of test particle orbits will be made ­ may generate counting rates in the XMS that are sufficient to overwhelm it. ...

... Usually, H I is seen as bright emission against a darker background, but under the right viewing conditions, it can also be seen as dark absorption against a brighter background. In the case where the background is itself H I emission, the hydrogen is said to be self-absorbed, and the radiative transfer process is termed H I self-absorption (HISA). ... Shown below is a single CGPS H I 21cm spectral line channel at a radial velocity of -41 km/s in the Local Standard of Rest, at l =140њ, b =+1њ. ...

... Telescopes ћ Binoculars ћ Microscopes . Meade Ultra-High Transmission coatings (UHTC ) Group . ... Meade Standard Coatings: The optical surfaces of all Meade telescopes include high-grade optical coatings fully consistent in quality with the precision of the optical surfaces themselves. ... These specialized, and extremely advantageous, coatings are offered here as the Meade Ultra-High Transmission Coatings (UHTC) group, a coatings group available optionally on many Meade telescope models. ...

ATNF Home . ... About ATNF overview . ... Australia Telescope Steering Committee . ... Australia Telescope User Committee . ... Staff list | ... Australia Telescope Compact Array . ... Australia Telescope Online Archive (ATOA) . ... VLBI . ... CSIRO ATNF Data Archives . Australia Telescope 20GHz Survey . ... Visiting Australia Telescope Compact Array . ... Australian SKA Pathfinder webcam . ... Australia is one of the co-hosts of the SKA . ... Very low frequencies observations with Pathfinders . ...

... Exposure Time Calculator (ETC) . ... ESO - Public Surveys . ... the recommended values to use for DIT, . ... Detector on-chip integration (DIT): seconds. to your chosen value - a separate page gives recommended values to use for DIT - for modes 1 and 2 below you may wish to start with the maximum recommended values as these will minimize the effect of read noise (a total object exposure of Y secs with DIT=X secs will produce Y/X lots of read noise) and give you a lower limit on the time needed. ...

APO/GIFS Instrument Factsheet The Goddard imager and Integral Field Spectrograph (GIFS) has recently been commissioned on the APO 3.5 m telescope. This factsheet presents a high level overview of the GIFS instrument. ... GIFS Imaging The GIFS imaging mode is used for imaging science and target acquisition for the IFS mode. ... Imaging Mode pixel scale: 0.168"/pixel · Comparison to Other APO 3.5m instruments: The GIFS field of view is smaller than SPICAM, but the filter set is far more extensive. ...

... Galaxies 99 Cosmic background with model of cloudy interstellar medium Yu. ... Figure 1: Averaged spectrum of the cosmic background I f in frequency range 0.25 200 MHz for the Galactic poles. ... First interpretation of the cosmic noise background spectrum at broad band frequency range 0.25 200 MHz with a model of the cloudy interstellar medium ISM is presented here. ... Synthesized background spectra I f for regions of the Galactic poles at the frequency range 0.25 200 MHz is presented in Fig. ...

... A comparison of the computed and experimental relations F max ( H), as well as comparison of drift scans of point sources across different horizontal cross-sections of the BP with the corresponding computed cross-sections were made. ... The drift scans of the point source 3С84 (H=87 o ) at the wavelength 7.6 cm across the horizontal cross-sections of the BP (black lines) and the computed horizontal cross-sections of the BP corresponding to them (red lines). ...

Large sunspots were occasionally seen far in the past without any instruments, when the sun was dimmed by thick haze, but not much was remembered of those observations. ... Sunspot Cycle (1850 - 1975) . One who was greatly influenced by Schwabe's discovery was an English gentleman of independent means, Richard Christopher Carrington , who devoted himself to the study of sunspots. ... Carrington had seen a flare, of the rare variety that is visible in white light (only about 50 are known). ...

To appear in "Fourth Workshop on Robotic Autonomous Observatories (2015)"RevMexAA(SC) METEOR OBSERVATIONS WITH MINI-MEGATORTORA WIDE-FIELD MONITORING SYSTEM S. Karpov, 1, 3 N. Orekhova2 G. Beskin, 1, 3 A. Biryukov3,4 S. Bondar,2 E. Ivanov,2 E. Katkova,2 A. Perkov, and V. Sasyuk3 RESUMEN 2 Favor de prop orcionar un resumen en espanol. ... The faintest detected meteors has the peak brightness about 10 mag, while the ma jority - from 4 to 8 mag. ... 2010; Karpov et al. 2013; Beskin et al. ...

... Armagh Observatory, College Hill, Armagh BT61 9DG, +44 (0)28 3752 2928 . ... Three sixth-form students from St Patrick's Grammar School, Armagh , used the Faulkes Telescope South in Australia in April to observe and measure HW Virginis , an unusual "binary" or double star system suspected to host one or two extrasolar planets orbiting the central stellar pair. ... Armagh Observatory and associated researchers hope to develop this work to look for further evidence of planet-hosting binary star...

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. ...