... 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. ...

... PRIMESRC : The INDEX value (see column description below) of the prime source. E_EXPRn : There are n ( ) occurrences of this keyword, one for each EPIC source list added to the RGS list. ... E_mBNDn : Similar to the E_EXPRn keyword, but this records the value of either ID_BAND (in the input RGS source file, when filemode =`modify') or bandids , which is used to select the EPIC sources and to calculate the RATE value, transmitted into the output RGS source list. ... real32 . ... EPIC_FILE . ...

... Step 1: The magnetic field line tracing from the satellite position up to magnetic equatorial plane using IGRF magnetic field model. Step 2: Tracing back from the point (produced on the Step 1) to the Ionosphere (by using only dipole magnetic field) . ... The magnetic field line tracing from the satellite position up to the Ionosphere (the stop trace altitude 110 km) using Main (dipole) + Extraterrestrial magnetic field model (for example, Tsyganenko [1987], or [1989], or [1990] ) . ...

Follow-up astrometry and recoveries are made with the ANU 40 inch (1.0-m) f/8 reflector at Siding Spring Observatory (IAU code 413). ... A routine follow-up of 2003 WY153 on 2003 Dec 15 became much more than routine when a faint object with unusual motion vector was found close to the target asteroid. ... During routine astrometry with the 1.0-m to improve the orbit of the Apollo asteroid 2004 CB, the asteroid was found on March 30 to have a short tail! ... Siding Spring Survey Main Page . ...

Program: TRACE Purpose: TRACE plots image values at user given positions as function of distance to a plot centre (in 2-d (sub)sets). Category: ANALYSIS, PLOTTING File: trace.c Author: M.G.R. Vogelaar Keywords: INSET= Give set (, subset): Only one subset is allowed. ... XYBOX= Give size of box around one pixel: [3,3] The resulting value at a selected position is an average of the pixels in the defined box around that position. ... POSITION= Give position x, y: Physical values are allowed. ...

... A photometric analysis was made of the simulated images using two of the widely available reduction programs, ROMAFOT (Buonanno et al. 1983) and DAOPHOT (Stetson 1987). ... The rebinned and expanded image gave better results (Fig. 7b), with the smallest errors in the order of = 0.04. ... Similarly to ROMAFOT, the image with the Moffat PSF gave significantly better results than the image generated with the Tiny Tim PSF; the errors in the magnitudes of the brighter stars were around = 0.02. ...

... 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. ...

... We have developed a suite of analysis tools and an on-line database for both the primary ChaMPlane X-ray data (source catalogs) as well as the optical counterpart data. ... The ChaMPlane VO provides access to our deep Mosaic optical (V,R,I,Halpha) images, catalogs of their optical photometry, Chandra images with exposure-map correction, X-ray source data and details of X-ray sources with identified optical counterparts. ... Chandra sources are displayed (right) in a smoothed Chandra X-ray . ...

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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) . ...

... 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 . ...