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. ...

... HST . ... HST Overview . ... Retrieving HST Data . ... The second is the internal geometric accuracy of an FOC image itself, including the correctness of the distortion model, the plate scale, and the image rotation. ... The accuracy with which HST places a target in the FOC field of view depends in a complex way on the target coordinate uncertainty, the positions of the guide stars in the FGS fields of view, and the alignment of the FOC imaging aperture with respect to the FGS reference frame. ...

... 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) . ...

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. ...

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) . ...

... 295, 2003 H. E. Payne, R. I. Jedrzejewski, and R. N. Hook, eds. The MAST Pointings Tables Pro ject Karen Levay, Paolo Padovani1 , Randall Thompson, Megan Donahue, Michael Corbin Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 Abstract. We have undertaken a pro ject to create a database of all HST imaging observations organized by position on the sky. ... Each sky region was called a "pointing." ... Users select the instrument pointings table they wish to search. ...

... Two files from two exposures (even from different observations or instruments) are taken as input. These may be EPIC event lists or two other additional files (attitude files, orbit files etc [see comments]). ... Warnings are given when the event files are deemed not entirely compatible (i.e. their INSTRUME or FILTER keywords are different). ... Given here is a summary of the current conditions whereby event files (or parts thereof [blocks/columns etc]) are or are not merged. ...

... Go to new wiki . ... TidNotes / . The antenna pointing models, subreflector rotation, first source coordinates etc are different depending on the observation. ... Build link with antenna and receiver, spacecraft 50 (VLBI), pass 0, two receivers. antenna startup . in NMC:CTRL Connection Control: . ... Check for: . ... ap move r=240 . ... select SC 99 and S band and [apply]) . ... You will need to enter offset commands at the NMC and observe the effect with xplot or the squarelaw sampler plot. ...

The steps in making a pointing model are listed below. ... While tracking the source rise to set, the tiedowns are pulled through a range of about 14 inches (taking 14 minutes) . ... We need a strong point source as sband because we want to measure the peak even when we are out of focus (so we can determine the best za location). ... Time: this takes about 80 hours (averaging 2 hours/source with wait time.. ... so 4 days 12 hours a day will probably work when you include the time for the source. ...

... The ROSAT Consortium (the Max-Planck-Institut fuer extraterrestrische Physik, the Goddard Space Flight Center, the Smithsonian Astrophysical Observatory, Leicester University, and the Astrophysikalisches Institut Potsdam) announces the release of the completed source catalogs of all ROSAT pointed observations. ... Detailed information about the catalog and methods of access to the catalog and data products can be obtained from the ROSAT Results Archive web pages in Germany, in the US, and in the UK:...

... Positions in 2000 - Jan - Feb - Mar - Apr - May - Jun - Jul - Aug - Sep - Oct - Nov - Dec . Positions in 2001 - Jan - Feb - Mar - Apr - May - Jun - Jul - Aug - Sep - Oct - Nov - Dec . Positions in 2002 - Jan - Feb - Mar - Apr - May - Jun - Jul - Aug - Sep - Oct - Nov - Dec . Positions in 2003 - Jan - Feb - Mar - Apr - May - Jun - Jul - Aug - Sep - Oct - Nov - Dec . Positions in 2004 - Jan - Feb - Mar - Apr - May - Jun - Jul - Aug - Sep - Oct - Nov - Dec . ...

... the time of observation . ... Observing the Changing Position of the Sun To Establish Cardinal Directions . ... Observations of the Sun's apparent movement across the sky and its pattern of rising and setting in the east and west horizon helped to establish the cardinal directions. ... The final stage of the Sun's return was marked by the observation that the Sun had reached its highest altitude when the full width of your mitted hand could fill the gap between the Sun and the horizon. ...

Atmospheric influence on the different radio-engineering system functioning . ESTIMATION OF ATMOSPHERIC OPTICAL CHARACTERISTICS AND REMOTELY SANSED IMAGE CORRECTION . ... Direct transmittance estimation results for 12 channels of the spectrometer CHRIS. ... We have managed to develop a direct method of estimating the discrete Normalized Atmospheric Point Spread Function (NAPSF) from available images alone, not using any external sources of information about the atmosphere. ... IRE RAS 1996-20 11 ...

... Between them, the following points are touched: ICRF-2 structure, ICRF Core sources selection, and some expected user's requirements. ... Suggested total number of sources is close to the number of sources already observed in the IVS and VCS sessions, and for most of them reliable positions are derived, mostly for declination > -40 deg. ... So, results of source position time series analysis heavily depend on method used for time series computation and should be used with care. ...

... astro-ph . ... Statistical Characterization of the Chandra Source Catalog . ... The first release of the Chandra Source Catalog (CSC) contains ~95,000 X-ray sources in a total area of ~0.75% of the entire sky, using data from ~3,900 separate ACIS observations of a multitude of different types of X-ray sources. ... In addition to these traditional catalog elements, for each X-ray source the CSC includes an extensive set of file-based data products that can be manipulated interactively. ...

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. ...

... Contact A Problem of an estimation of accuracy of the asteroid CCD observations . The Minor Planet Center supported by the Interntional Astronomical Union is the main office for keeping observational data of the small Solar System bodies and their investigations. ... At Pulkovo Observatory we are estimating an accuracy of the CCD asteroid observations obtained by amateurs and professional astronomers all over the World using the MPC database. ...

... 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. ...

For the calibration of RATAN-600 data you will need to Download Nobeyama Fluxes (1, 2, 3.75, 9.4, 17 GHz): year 1999 2000 2001 2002 2003 . Brief description of Work Scan . Main functions of processing, realized in the program are: . ... Correction of various (not fatal) defects of data; . ... Calculating of the lower enveloping curve or an average scan from observations data for a few days; . ... COMMENT This table contains the set (TFIELDS) of 1-dimensional (TFORM# . ... AZIMUTH = 'float' / . ...

Next: The Scenario Machine: Operational Up: Evolution of Magnetic Rotators Previous: Ejector-propeller hysteresis . ... The length of this segment is determined by the eccentricity. ... In this case no hysteresis occurs and transitions E -- P and the reverse take place in symmetrical points of the orbit. ... Here EP means a mixed state of the rotator at which it is in the ejector state during one part of the orbit, and in the propeller state during the rest of the orbital cycle. ...