... Q: How do I best determine an observation's actual orientation? ... The science header keyword ORIENTAT is populated by adding the angle between the HST V3 axis and the detector Y axis to what we will call the "commanded roll" (North to V3 through East). ... The commanded roll can be determined by subtracting the beta_2 from ORIENTAT. ... Relying on the jitter file's measured roll if a problem is found either with the science header population or with the execution of the commanded roll. ...

Next: Catalog Construction Up: Observations and Analysis Previous: Source Detections . ... It was assumed that the highest signal gives the most likely position of the source. ... Comparing the summed map with the maps from the individual energy ranges, the one which produced the smallest error box was chosen to represent the source position, as long as was greater than 4, a level chosen to reflect a reasonable degree of confidence in the detection. ...

... Current APO Weather . ... Search Site . ... Information for New Users . ... Technical Staff pages . Night Logs and Mailing Lists (maintained by APO) . ... Technical Documents and Database Search . ... Observer's Documentation and Procedures . ... Problem Reporting and APO Technical Documents Database Search . ... APO Drawing/Document Management Procedures . ... APO Technical Documents Database Search . Home Astrophysical Research Consortium . ... Mail Lists (maintained by APO) . ...

SAS home . ... This thread contains a step-by-step recipe to extract PN spectra of a point-like source observed in Imaging mode and to create associated response matrices, starting from a calibrated, concatenated event list (either produced with epproc or available as PPS product; here it has the assumed file name PN.fits ). ... The users should note that the SAS metatask xmmselect allows them to interactively define source and background regions (via ds9) and to run backscale on the fly. ...

... This problem affects all FITS-files generated between 16 September and 9 November 2004. ... DETAILED DESCRIPTION -------------------- AFFECTED KEYWORDS : The affected keywords are: CRVAL2A and CRVAL3A (beam position on sky in RA/Dec) CRVAL2B and CRVAL3B (beam position on sky in Az/ZA) CRVAL2G and CRVAL3G (beam position on sky in l/b) CROFF2 and CROFF3 (map center offset in RA/Dec) CROFF2B and CROFF3B (map center offset in Az/ZA) BEAM_OFFRAJ and BEAM_OFFDECJ (total beam ...

... Classes . ... casa . casa::MSMainEnums . ... Enums for the MeasurementSet main table. ... Inheritance diagram for casa::MSMainEnums: . ... DATA_DESC_ID , . ... This class contains the enum defininitions for the main MeasurementSet table. ... enum casa::MSMainEnums::PredefinedColumns . ... Int . ... Int. DATA_DESC_ID . ... State Id, points to STATE table with info on current observing mode, calibration and reference signals etc. ... enum casa::MSMainEnums::PredefinedKeywords . ... Antenna subtable. ...

Region markers can be moved, resized, rotated, zoomed, deleted, and can change geometric type. ... For example, markers placed on astronomical catalog positions should be fixed so that one cannot accidentally move them off the specified position. ... Parameters can be fixed using the fix option of the regions public access point (for fixing classes of markers) or by means of a fix keyword in the definition of an externally loaded marker. ... In the command: echo "regions fix all -position -size" | ...

The close position of main satellite and subsatellite (distance between them about 1000 km) and using the similar sets of Faraday cups (VDP and VDP-S) with high resolution measurements (up to 16 Hz for the main satellite and up to 10 Hz for the subsatellite) allow us to determine the small-scale variations of the magnetopause shape and position and to estimate the velocity of the magnetopause motion. ... Two point observation of the magnetopause motion: the INTERBALL project. ...

Next: Star Formation Rate and Up: No Title Previous: Calculation of Evolutionary Tracks . To start calculations, we choose the distributions of the initial binary parameters: the mass of the primary ZAMS component, , binary mass ratio, , orbital separation a . ... whereas the mass ratio distribution is not. ... The zero assumption often made is that the mass ratio distribution has a flat shape, that is binaries with a high mass ratio occur as frequently as those with equal masses. ...

... Using a simple 2-D Gaussian Point Spread Function (PSF) on a constant (flat) sky background, I derive a theoretical photometric and astrometric performance model for analytical and digital PSF-fitting stellar photometry. ... The photometric performance is maximized when either the effective background area or the effective-background-level measurement error is minimized. ... An important, but frequently ignored, noise source is the uncertainty of the measurement of the effective background level ( )...

... Pointers to Pointers . ... Pointers to a Function . ... We have introduced some advanced pointer issues already. This chapter brings together some topics we have briefly mentioned and others to complete our study C pointers. ... main(int argc, char **argv) . ... These are the only arguments main accepts. argc is the number of arguments typed -- including the program name. argv is an array of strings holding each command line argument -- including the program name in the first array element. ...

... With enough velocity, a spacecraft can break loose from the Earth's gravity and enter an orbit around the Sun, like that of a planet. If it then orbits the Sun with the same period as the Earth--one year--it may keep a fixed position relative to Earth. ... If the distance is just right--about 4 times the distance to the Moon or 1/100 the distance to the Sun--the spacecraft, too, will need just one year to go around the Sun, and will keep its position between the Sun and the Earth. ...

From Herschel's catalog, the first accurate stellar parallax measurement of 0.32 seconds of arc for the star 61 Cygni was published by the F.W. Bessel in 1838. ... This distance is equivalent to 3.26 light years. ... The Universe was now a large place and the intrinsic energy output of the stars had to be huge in order that their light could reach us. ... An Orbit in Curved Space This is a prediction made by General Relativity and confirmed by direct observation of Mercury. ...

IBIS Data Analysis . ... IBIS . ... Flat Fielding - Introduction . The images obtained by IBIS will have intensity variations across the field of view that are not due to the solar image, but rather caused by instrumental effects that alter the observed intensity in each point of the field of view. ... IBIS Flat Fielding Techniques . ... Therefore, it is desirable to obtain the flat field measurements center on a point along the equator near the heliographic center of the solar disk. ...

These observations are aimed at fully charactering FORS1 photometric system (UBVRI zero-points, color-terms and extinction coefficients) for the Tektronix 2048x2048 pixel CCD (24µm px) . To this aim, the two Landolt/Stetson photometric fields SA95 and SA101 will be observed on a number of epochs and at different airmasses during February and March 2007. ... SA101 . ... OBs for SA101 have to be observed during evenigh twilight (exceptions are expected for the second half of March) . ...

... Time calculated from Fermi GBM Trigger Time = 14:12:08.67 ( Connaughton, GCN 9230 ). 1% coincident with our start zero image time. 3x3 degrees around Swift XRT position . ... SUBJECT: GRB 090424 : MASTER-Net prompt optical limit DATE: 09/04/25 20:29:42 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs E. Gorbovskoy, V. Lipunov, V.Kornilov, A.Belinski ... Our observations results: ---------------------------------------------------------------------- Fermi GRB Trigg.* ...

... The final mosaic is presented, along with a catalogue of 4934 sources detected above 6 sigma. ... This file GMRT _LH2_dr1.dat 95 4934 GMRT LH2 sourcelist of 4934 sources -------------------------------------------------------------------------------- Byte-by-byte Description of file : GMRT _LH2_dr1.dat -------------------------------------------------------------------------------- Bytes Format Units Label Explanations ...

... Once "point" is read, assumes all the following x,y coordinates are points. ... Program asc2dxf c reads set of x,y coordinates and writes a .dxf file for aperture plate. character*4 xop1,xop2 character*12 outfile 1 format ( 1h0 /7hSECTION/1h2/8hENTITIES/ 1h0 ) 2 format (6hCIRCLE/1h8/1h1/2h62/1h3) 3 format (4hLINE/1h8/1h1/2h62/1h3) 4 format (5hPOINT/1h8/1h1/2h62/1h3) 5 format (2h10/5h43.00/2h20/5h43.00/2h30/5h0.000/2h40/5h43.00/ 1h0 ) 6 format (2h10,/,f6.3,/,2h20,/,f6.3,/,2h30/5h0.000) 7 ...

... Exposure Time Calculator (ETC) . Survey processing . ... VISTA is a 4-m class wide field survey telescope for the southern hemisphere, equipped with a near infrared camera (1.65 degree diameter field of view at VISTA's nominal pixel size) containing 67 million pixels of mean size 0.34 arcsec and available broad band filters at Z,Y,J,H,K s and a narrow band filter at 1.18 micron. A wide field visible camera, if constructed, could also be used on VISTA. ... Tile . ... ESO VISTA Public Surveys . ...

Institute of Applied Astronomy Russian Academy of Sciences Method of Determining the Orbits of the Small Bodies in the Solar System Based on an Exhaustive Search of Orbital Planes Dmitrii Vavilov, Yurii Medvedev Introduction to the problem: Let we have n 3 positional observations of a body: points in time ( = 1, ) , right ascensions , and declinations . ... Determination of the orbit using the Gauss method of determining orbital elements based on two heliocentric positions and points in time. ...