... The HST uses an onboard model of its orbit to perform in real-time various control functions relating to spacecraft operations and observation support. ... New coefficients for the ephemeris are updated every other day, and are archived as FITS keywords for each HST observation data set. Using these coefficients,an observer can perform a variety of calibration and characterization calculations relating to the orbital position and velocity of the telescope. ...

... HST . Using Multiple FP-POS positions with COS observations . ... Data . ... HST Peer Review Process . ... HST Overview . Overview . ... Phase I Proposing . ... Retrieving HST Data . ... COS Data Handbook . ... The use of multiple FP-POS positions for each CENWAVE position of the COS FUV detector was strongly encouraged in the Cycle 19 Call for Proposals, Primer, and COS Instrument Handbook, as this improves the limiting S/N and allows the effects of flat-field artifacts to be minimized. ...

... The J, H and K bands are characterized by a bright background, such a background is mainly due to the emission of atmospheric lines and of thermal radiation. ... If the source cover a large fraction of the slit, spectra off-source must be observed to adequately sample the sky background. ... The on chip integration time (time spent in each position of the slit) must not exceed 40 seconds in J and H bands and 60 seconds in K band. ... We suggest a sequence of 10 for each elementary integration time. ...

The Wind spacecraft. ... It was designed to observe the solar wind approaching Earth, from a position near the Lagrangian point L1, and it is part of the International Solar-Terrestrial Physics (ISTP) Initiative . ... The original plan called for "Wind" to approach its final station over two years, undergoing two close encounters with the Moon to boost its speed. ... For additional details and updates, see the home page of the "Wind" mission. Exploration" home page (index) Glossary . ...

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. ...

... About ATNF overview . ... Australia Telescope Steering Committee . ... Australia Telescope User Committee . ... Staff list | ... Murchison Radio-astronomy Observatory . ... Parkes radio telescope . Australia Telescope Compact Array . Mopra radio telescope . ... Australia Telescope Online Archive (ATOA) . ... VLBI . ... Australia Telescope 20GHz Survey . ... This message : [ Message body ] [ More options ( top , bottom ) ] . ... radio observations for the exploration of our Solar System and . ...

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. ...

... region (region-6.2.2) [xmmsas_20030110_1802-5.4.1] . ... The region task will automatically determine the optimal source and background extraction regions for a detected source in an XMM observation. ... The regions are defined in sky coordinates. region will attempt to maximise the area of the extraction region for each source, whilst ensuring that the extraction regions of neighbouring sources do not overlap, and that the background extraction region for a given source excludes neighbouring...

GRANAT is the Russian x-ray sattelite launched to the high apogee orbit (200,000 km) and operated almost for 10 years (1989 -1999) , carrying out four major instruments: French SIGMA coded-mask hard x-ray telescope (30-1000 keV), Soviet ART-P coded-mask telescope (2??-60?? keV), all-sky monitor WATCH (6-150 keV), and a gamma-burst detector PHEBUS . ... Since September 1994, GRANAT is in the survey mode. ... Explore pages devoted to individual GRANAT instruments (including main scientific results): . ...

Ground Support of RadioAstron . Control and Tracking Stations . RadioAstron satellite control (command transmission, telemetry, orbit measurements) will be conducted from Evpatoria and Bear Lake control stations. ... Coarse orbit measurements will be carried out from control stations. Each measurement takes ten minutes. ... Orbit measurements at tracking stations give only radial component of spacecraft velocity but the measurements are going continuously during observing sessions. ...

... The procedure simply observes ON