... Meta Index / Home Page / Description / Specifying source region shapes . When radiusstyle =`contour', the task calculates the source region shape as an elliptical locus which approximates the contour of the PSF at a given flux value. ... Clearly, in order to calculate the shape of such a flux contour, it is necessary firstly to normalize the PSF to the source brightness and secondly to determine the flux level (in `brightness' units per pixel) at which to find the contour. ...

... 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. ...

Target Acquisition Reference Information . ... In almost all cases where an onboard acquisition will not work (because the object is in a crowded field, or is variable, or is a moving target), it is sufficient to use an early acquisition to get a WFPC2 or FOC image a few weeks in advance of the GHRS observation. ... Explicit BRIGHT and FAINT limits may be specified if you desire, although there is an increased risk of a failed acquisition unless you are confident of those fluxes. ... MAPs . ...

. 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.

... User Guide ] Task: moment Purpose: Calculate moments of a Miriad image. ... Key: in The input image. No default. ... Key: mom -3: Velocity at peak intensity using a three-point quadratic fit around the peak (km/s). 2: Peak intensity using a three-point quadratic fit (units same as individual channels). ... The moments are calculated independently for each pixel using spectral channels with intensity satisfying the specified clip range. ... Key: axis Axis for which the moment is calculated. ...

Next: 1--Dimensional Images (``Spectra'') Up: 2--Dimensional Images Previous: Patterns . ... CREATE/RAMP . produces square two--dimensional images of user--specified dimensions, with mean flux per pixel of 100 units, of user--specified slope of the plane, and with the plane itself sloping at a position angle. ... CREATE/WAVE . ... Again, the image is two--dimensional, of user--specified dimensions, and with user--specified amplitude and period. ... The mean flux per period is 0 units. ...

... Note that the size of a region cannot be specified in celestial coordinates (e.g., arcminutes) for this task (1 pixel = 0.5 for the ROSAT HRI). xs srcint source qpoe file ( ): xdata$rh110267.qp source region descriptor ( ): c 2326 4406 120 background qpoe file ( ): bkgd region descriptor ( ): a 2326 4406 150 200 output root name (_ccr.tab): (arlac) --- Creating aspect histogram table from qpoe --- --- Computing vignetting ...

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. ...

... Restrictions ) are used. If specified form of output is EMP then astrometric equatorial coordinates are printed in the form usual for Ephemerides of Minor Planets, with formal precision of 0.01 minute of time in R.A. and 0.1 minute of arc in declination. ... It should be noted that the near-opposition ephemerides are not calculated for bodies/ points with numbers from –12 to 0 (in case they are included into task for computation of such ephemerides only their names are displayed in the results). ...

asncombine -- Process and combine images in one or two NICMOS associations asncombine association . ... set to yes to include error planes in co-added images error. background . ... This is useful to use different background subtractions for different images. fheader . set to yes in order to multiply the background by the value of keyword "factor" in the image header. ... Set to yes to use quadrants statistics save in the image header from previous runs of asncombine. regquad1 . ...

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. ...

Stellarium 0.12.3 . ... Classes . ... StelSkyLayerMgr Class Reference . ... loadSkyImage (const QString &id, const QString &filename, double ra0, double dec0, double ra1, double dec1, double ra2, double dec2, double ra3, double dec3, double minRes, double maxBright, bool visible) . ... loadSkyImageAltAz (const QString &id, const QString &filename, double alt0, double azi0, double alt1, double azi1, double alt2, double azi2, double alt3, double azi3, double minRes, double maxBright, bool visible) . ...

... Imagine that for every pixel in the color image, you take its luminance value (that's how bright it appears). ... In the end, you will have a histogram which counts how many times each luminance value appears in the image (that histogram can be used to analyze the distribution of the luminance values in the image). ... For the watermark effect, we want to use the same value that we used in the Stretch Contrast step, so that the lightest color will be in fact white (255), and nothing will get clamped...

. 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

... METHOD . ... java.lang.Object ij.plugin.filter.BackgroundSubtracter . ... Implements ImageJ's Subtract Background command. ... With both, rolling ball and sliding paraboloid, the image used for calculating the background is slightly smoothened (3x3 average). ... boolean . ... This method is invoked by a Generic Dialog if any of the inputs have changed (CANCEL does not trigger it; OK and running the dialog from a macro only trigger the first DialogListener added to a GenericDialog). void . ... void ....

... Luminosity (L) · · · · A source's luminosity is the power that it emits in radiation. ... NB Astronomers often say `flux' when they mean `flux density' · SI units are Wm-2Hz -1 -26 filter · Also used are Jy 10 Wm-2Hz -1 E= РРРF d dA dt Specific Intensity, Surface Brightness (I) · Specific intensity (or surface brightness) is the power received (or emitted) per unit area per unit frequency per unit solid angle. ч F at surface of a spherical source = I · · Specific intensity is independent of distance...

Pulkovo NEO Page . ... EPOS Software Package . ... EPOS ( E phemeris P rogram for O bjects of the S olar system) is the Windows PC application for study and ephemeris support of observations of the Solar system objects. ... It controls the part of common data and transfers the control to one of the programs that solve the restricted set of tasks. ... So with the EPOS software package one can calculate the accurate ephemerides for many objects and get the quick illustration of their motion as well. ...

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 . ...

You Can Make Stellar Images Brighter . Articles | ... A few months ago I wrote an article titled "You Can’t Make Them Brighter". So why am I now writing that you can make them brighter. ... The image of a focused star is actually a small disk called the Airy disk, named after the 19 th century scientist Sir George Airy. ... For a given aperture, a smaller Airy disk means that the light is focused to a smaller disk and is therefore brighter. ... www.astronomy.net . About Astronomy Net | ...