... HST . What is (epsilon_Nspix)' and how is the spectroscopic S/N calculated? ... Missions . ... Data . ... HST Overview . ... Retrieving HST Data . ... epsilon_Nspix)' is the fraction of the point source energy within N_spix pixels in the spatial direction. For spectroscopic observations, S/N calculations are performed over N_spix x N_lpix pixels, where N_spix is already defined and N_lpix is the number of pixels for a resolution element in the dispersion direction, i.e. 2 px for STIS and ACS. ...

... We have calculated the binary coalescence rate with time using the ``Scenario Machine'' code, which allows us to simulate evolution of large ensembles of binary stars in an artificial galaxy using a Monte Carlo method (see Lipunov 1992, Lipunov et al 1994, 1995 and references therein). ... The source evolution in a galaxy with given star formation rate is thus calculated as , where is the redshift at the turn-on of star formation, which is the second important parameter of the model. ...

... The RA_PNT , DEC_PNT and PA_PNT keywords, together with the AVRG_PNT keyword which records the type of average used, are meant to describe the average value of the spacecraft attitude during the exposure. ... attsource =`binned': whatever values of the PNT keywords calculated by attbin and stored in the inbinnedattset dataset are simply copied over. attsource =`odf': PNT values are sought from the header of the dataset pointed to by pntkwdset . ... In this case AVRG_PNT is set to `FIXED'. ...

Next: *upspecrdf, downspecrdf* - Transform Up: Spectral Analysis Previous: *grid_plot* - Plot Results . The conversion of count rate to flux depends on the intrinsic spectrum of the source, so xflux must be used in conjunction with fit . Fit generates a table of the best fit intrinsic spectrum ( _int.tab extension). xflux uses this table to calculate either the integrated flux between two energy limits or the flux density at a specific energy. ... This produces ``..._obs.tab'' file. ...

As it is in Ephemerides task, O–C can be calculated with different accuracy. ... It presents three modes of accuracy. One can calculate position of a minor planet by the formulae of elliptic motion starting from the fundamental set of elements for given minor planet. ... Also there is possibility to calculate positions taking into account perturbations from different sets of perturbing bodies by numerical integration ( Integration mode). ... Accuracy of integration is equal to 10**(–10) AU. ...

... Next: The PROS Big Up: Software Systems Previous: Data Reduction Software . ... The srcinten task provides PROS users with a tool to compute count rates for point sources in the ROSAT High Resolution Imager (HRI). ... Corrected upper limits are cited at locations where the count rate falls below the source detection threshold. ... Srcinten is a new PROS task that computes and applies the above correction factors to the net counts in a user-specified aperture. ...

... This is done from within the keyword handler work() which is activated by the keyword WORK= . ... h #include init.h #include finis.h #include userfio.h #include ggi.h /* * Keyword handler for QUIT= */ static void quit(ident id, char * key , int code, void *arg) { bool finished=toflog(FALSE); ( void )userflog( , 1, 2, key , ); if (tobool(finished)) finis_c(); } /* * Keyword handler for both NUMBER = and GETAL= */ static void number (ident id, char * ...

... The cross entropy for this complex image is given by ( 16 ) and ( 17 ). ... Differentiating ( 31 ) with respect to and , we find the gradient of is given by . and upon differentiating once more we find the Hessian (curvature) matrix of has the form . ... and its Hessian matrix reads . ... From ( 16 ) and ( 17 ), we find the components of the gradient vector of the cross entropy are given by . ... Differentiating once more we find the components of the Hessian of the cross entropy to be given by . ...

... The plot widgets as shown below are created using Calibrate|Visibility|PLOT . The one on the left is the general plot selection widget, the one on the right, the (data) index selection widget, is created when additional input is required as to the indices of the selected data. ... The calibration is applied to all stars selected in the plot selection widget. ... Below is the screen print after clicking on "Calibrate". Solution calculated for OB= 1, Bl= 1, Ch= 2. RMS [%] = 1.876) . ...

... Alfa_ang is a GUI for the rotang routine. The purpose of this routine is to calculate the optimum rotation angle for ALFA given the RA and Dec of a source and the date and time of the observation. The routine also returns the azimuth and zenith angle of the telescope at the requested time, thus it can be used to find the correct rotation angle and azimuth for the Fixed Azimuth Drift Scan observing mode used by the AGES drift precursor observation. ... To run alfa_ang at Arecibo: . ...

The radio power formula (see Hogg D.W. ) is . where luminosity (bolometric) distance is . Deceleration parameter is for Lambda = 0. The fitting curve is used for the radio power calculation. The Hubble constant , the deceleration parameter , the redshift of radio source , the emission comoving frequency , and the observed flux density can be choosed as parameters .

... Meade Instruments Corporation . ... How to Calculate Power . How to Calculate Power: The magnification, or power, at which a telescope is operating is a function of the focal length of the telescope's main (objective) lens (or primary mirror) and the focal length of the eyepiece employed. ... Example: The Meade DS-2070AT telescope has an objective lens focal length of 700mm; when this telescope is used with a 25mm eyepiece, a power of 700/25 = 28 power (written as "28x") results. ... about meade | ...

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Blackholes Forum Message . ... So How Can We Calculate The Mass Of The BH? ... Posted by Lukas on January 25, 2005 14:00:31 UTC . ... Gravity is the weakest force of all - secretary - January 25, 2005 - 18:53 UTC . Singularity - bazukaz - January 25, 2005 - 23:19 UTC . Only in theory - secretary - January 26, 2005 - 02:15 UTC . ... www.astronomy.net . ... Forum posts are Copyright their authors as specified in the heading above the post. "dbHTML," "AstroGuide," "ASTRONOMY.NET" & "VA.NET" . ...

This diagram shows the six superimposed "layers" of the CSS table model. This diagram illustrates the algorithm for calculating a cell's final background. ... The diagram shows how, looking down on the six rectangles, one may compute the background color of each cell. ... A cell without a background color in the top layer is depicted as a "window" onto the lower layers, which give its final background color. ...

Input function: . Input X: .

... 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. ...

Russian SHAREABLE DATA CENTER Institute of Solar-Terrestial Physics SB RAS . ... The algorithm and appropriate program for decametric radiosignal propagation conditions prediction for paths from 500 to 9000 km have been developed at ISTP SB on the basis of normal wave method (AltyntsevaB.I,Iliyin N.V., Kurkin V.I. and others //Decameters channel simulation on the base of normal wave method . ... Solar activity indices are chosen automatically from the prediction date from the database . ...

This section is on a higher level than the rest, and is primarily meant for advanced users, who may wonder how orbital motion is actually derived. ... As stated earlier, the motion of a satellite (or of a planet) in its elliptical orbit is given by 3 "orbital elements": . ... 3) The mean anomaly M , an angle growing at a steady rate, increasing by 360 degrees each orbit . ... In polar coordinates ( r,f ) describing the satellite's motion in its orbital plane, f is the polar angle. ... The angles: . ...

RATAN-600 radio telescope . ... In the "radio-Shmidt telescope" mode the antenna system the South sector of the main mirror with the flat mirror ("South+Flat") of the RATAN-600 radio telescope is used. ... The antenna system the South sector with the flat mirror. ... The flat and circular mirrors of the RATAN-600 form the basis of the system. ... In the case of antenna system "South+Flat" the planoid is flat mirror, the circular reflector of RATAN-600 is the second mirror. ...