. This diagram shows a small table with three transparent cells and illustrates how their final background is determined. The table consists of two rows. Four (labeled) cells lie in the first row, but the second cell spans the first and second row. The first, third, and fourth cells of the second row are "empty". Each non-empty cell has a red background and a double black border. Each empty cell has the table's background color (specified as #ff0) as its own. Return to image.

... Near Infrared Camera and Multi-Object Spectrometer Instrument Handbook for Cycle 17 > Chapter 9: Exposure TimeCalculations > 9.1 Overview: Web based NICMOS ETC . 9.1 Overview: Web based NICMOS ETC . ... The imaging NICMOS WWW ETC is documented in an Instrument Science Report (Arribas, NICMOS ISR-2004-002 ). ... Additional information on the ETC and its structure can be found in the Instrument Science Reports (ISRs) posted on the STScI NICMOS Instrument Web page. http://www.stsci.edu/hst/nicmos/ . ...

... This example uses an error array to determine the errors in the radial profile. task: imcnts . ... xs imcnts err=vigsnr_err expo=xdata$snr_exp.pl expthr=95.0 bkgdex=xdata$snr_exp bkgdth=95.0 bkgderr=vigsnr_err # Run the imcnts task with the appropriate parameters source image file : vigsnr # vigsnr.imh source region descriptor: a 300 300 0 50 n=5 # 5 annuli centered at 300 , 300 , 0 and 50 pixels min/max radius background image file or cts/pixel: cr # From the same ...

... 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. ...

XMM-Newton Science Analysis System Page: 1 esensmap July 1, 2008 Abstract Calculate EPIC sensitivity map 1 Instruments/Modes Instrument Mode EPIC MOS: IMAGING EPIC PN: IMAGING 2 Use pipeline processing yes interactive analysis yes 3 Description This task creates a sensitivity map giving point source detection upper limits (vignetting corrected source count rate corresponding to the likelihood of detection as speci ed in the parameter le) for each image pixel. ...

BACKGROUND . ... Electron bombarded silicon (EBS) gain makes the CCD interesting for keV electron detection. Ionizing particles absorbed in silicon create electron-hole pairs at the average rate of one per 3.64 eV incident energy. ... The variance in the number of electron-hole pairs created is given by the Fano factor for silicon (.1-.2) times the number of pairs created. When we use a CCD as a detector of ionizing particles, we would like to collect all of the electrons created. ...

Program: HIFLUX Purpose: derive fluxes and standard deviations from HIRAS images File: hiflux.src Category: IRAS Author: Do Kester Keywords: *** MAPS= Max number of maps to be processed simultaneously [4] All maps should be of the same size, and presumably of the same field. ... COLIND= Color index for plot colours [standard] *** LOCAL= Calculate local background [No] The background is determined as the median of the points within the form selected with SELECT=. ... But see also RADIUS=). ...

The ESA/ESO Astronomy Exercise Series 2 . The Distance to Messier 100 as Determined by Cepheid Variable Stars . ... The small variations in distance to the individual Cepheid variable stars in the Cloud are negligible compared with the much larger distance to the SMC. ... In this way Cepheid variable stars can be used as one of the 'standard candles' in the Universe that act either as distance indicators themselves or can be used to calibrate (or set the zero point for) other distance indicators. ...

... The formation of spectral disturbances of Cosmic Background Radiation (CBR) during the period of hydrogen recombination at redshift is considered. Special attention is paid to the decimeter and meter wavelength band. ... In this paper we will return to the question on the spectral lines caused by recombination of hydrogen discussed by Dubrovich (1975) , in the longer wavelength part of spectrum of the CBR. ... A synthesis of recombination radiolines spectra is divided into several stages. ...

Next: Imaging Polarimetry with NICMOS Up: NICMOS Data Calibration and Previous: The Photometric Performance of . ... NICMOSlook and Calnic C . ... Extracting spectra from a large number of NICMOS grism images requires a convenient interactive tool which allows a user to manipulate direct/grism image pairs. ... NICMOSlook and Calnic-C are two programs that were designed to take advantage of the fact that the NICMOS grism mode typically consists of taking both a direct and a grism image. ...

These are very prominent absorption lines is most all galaxies. ... These pair of absorption lines will appear in all the spectra and they should be your principle source for determining the redshift. ... When this applet opens you will see an iconic representation of galaxies in the left hand side of the applet and a target area in the right side of the applet. ... Note: What you are doing in this excercise is identical to what Hubble did in the 1920's and you are using the same galaxies. ...

T he Siding Spring Survey (SSS) is a Near-Earth Object search program that utilises the 0.5-m Uppsala Schmidt Telescope at Siding Spring Observatory, N.S.W., Australia. ... The mission of the Siding Spring Survey is to contribute to the inventory of near-earth objects (NEOs), or more specifically, the potentially hazardous asteroids (PHAs) and comets (PHOs) that may pose a threat of impact and thus harm to civilization. ... Based on the CSS Mission page . ... Siding Spring Survey Main Page . ...

Calculation of Atmospheric Emission Measured by Gregorian Feed Horns Paul F. Goldsmith September 16, 2001 As we use higher frequencies, emission from the Earth's atmosphere becomes more sig- ni cant. ... To use this program, you input the altitude, temperature, and precipitable water vapor (pwv) in mm. ... I have run the ATM code for several values of pwv with plausible temperature, and generated the zenith sky temperature as a function of frequency between 1 and 15 GHz. ...

... As stable VLT work horses during the past 8 years obviously the two FORSes have in many ways also been instrumental to the definition of the VLT queue observing paradigm which includes both systematic collection of calibration data, online and offline reduction pipelines. The original concept for the photometric calibration and the FORS imaging pipelines involved acquisition of simple twilight images which were used for flatfielding, and observation of Landolt photometric standards. ...

... The file names' construction . The flight (m) stage's file set . ... the orbital data used for the flight operation monthly (m) long-term planning, . ... The orbital calculations are based on the initial orbital data determined by KIAM RAN using the orbital radio- measurement treatment. The determined initial orbital data are presented as a state vector (satellite position and velocity) in the J2000 reference. ... Accept the file with extension '.bgr', where the Moscow time (MT=UT+3h) is used. ...

Radiative losses have been determined by using the Arcetri Code line emissivities for each element calculated adopting a plasma electron density of 10 10 cm -3 . Each emissivity line is structured using the following format: An example from the Mg file (Phot cm 3 s -1 ) is given below: . ... Mail comments regarding interface to landi@poppeo.nrl.navy.mil Mail comments regarding spectrum data to mlandini@arcetri.astro.it, landi@poppeo.nrl.navy.mil ...

... The Millennium that Defined Earth . ... Fittingly named The Horsehead Nebula it is embedded in the immense complex of star forming gas and dust surrounding the Orion Nebula some 1,500 light-years distant. ... The Dust and Ion Tails of Comet Hale Bopp . ... NGC 1850: Gas Clouds and Star Clusters . ... The December solstice brings the beginning of Winter to Earth's Northern Hemisphere and Summer time to the South! ... Simulated Supergiant Star . ... Consider this "star in a box". ... December . ...

THE PHOTOMETRIC RESEARCHS OF THE MERCURY'S SURFACE BY MEANS OF DIGITAL MODELS. ... The surface brightness of Mercury was measured Danjon (1933, 1949, 1953) and Harris (1961) in phase angle 3o-123o. The analysis of the various data of the integral photometric gives the results of determination of the main photometric constants for Mercury. ... THE PHOTOMETRIC RESEARCHS OF THE MERCURY'S SURFACE: S.G. Pugacheva The surface brightness of the Mercurian images was established on the geologic map Mercury. ...

Next: Polarization efficiency: size/shape/orientation effects Up: Optical properties of cosmic Previous: The 2175? feature . To model the interstellar polarization one needs to calculate the forward-transmitted radiation for an ensemble of non-spherical aligned dust grains. ... Let non-polarized stellar radiation passes through a dusty cloud with a homogeneous magnetic field. ... The angle between the line of sight and the magnetic field is ( ). ... where the angle is connected with and ( ). ...

... The evolution of a binary system is considered as a sequence of stages the duration of which are defined by the shortest evolutionary time-scale of one of the binary components (see the list of the evolutionary states of stars in Sections 3 and 4). ... Then the code finds a new stage the binary should transit to, with this stage being determined by the evolutionary states of both components, and calculates it. ... However, one can use the algorithm described above to model their evolution. ...