. Listed below are some issues that are relevant to different modes of observing. 08feb10: converting on/off position switch data to Kelvins. 13dec09:on,off position switching offsets. Rms degradation vs offsets. feb05: doing drift scans in J2000 coordinates. How much do we move. jul04: Cormapping. Removing Tsys after bandpass correction with mean,median, and robust average . nov02: Trying to remove the bandpass using the calOn-calOff. home_~phil

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... 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. ...

Next: About this document Up: FOC Image Restoration Using Previous: Mathematical Methodology . ... Use of a mask was required to ensure that the saturated data were ignored in the resultant restoration which these authors obtained with an observed PSF. ... Hollis and colleagues obtained two public domain FOC F/96 images of the binary system R Aquarii and an observed PSF both in the light of twice ionized oxygen which emits a spectral line at 5007 ?. ... These images are not identical in details, . ...

We model the spectral chanages of late oxygen-rich Miras observed in different pulsation phases. From a combination of variable near-IR spectra and UKIRT spectrophotometry of the 9.7 \mu m silicate dust emission feature in different phases we study the influence of the changing atmospherical circumstances on the conditions in the circumstellar dust shell. ... A comparision with the modelling results for another long period Mira U Ori is also provided. ...

The potential of masers to act as probes of their environment has long been recognised, but to date has proven very difficult to realise. ... 2001, Sutton et al. 2001). Masers are variable on timescales of weeks to months and one of the major limitations in previous attempts at multi-transition analysis has been the uncertainties introduced by combining observations made over many years using a variety of instruments with differing spectral and spatial resolutions and polarisation properties. ...

... In order to compare the number of different evolutionary stages obtained and X-ray luminosity of the chosen X-ray sources with the observed galactic values we use the sum of C/O+O/C , where C and O are the calculated and observed values of a given binary type, respectively. If we make comparison for a number of different binary species (for example, we compare the number of CV, number of X-ray pulsars,   total X-ray luminosity of LMXB, etc.), we write this criterion in the form: . ...

Observed maximum rotation velocity uncorrected for inclination effect. This quantity is calculated from 21-cm line widths at different levels and/or rotation curves (generally in H_alpha). ... These data are characterized by some secondary parameters: telescope, velocity resolution, level of the 21-cm line width and bibliographic reference. ... we start from a standard sample (a set of measurements giving a large and homogeneous sample). ... HyperLeda . ...

... Exposure Time Calculator (ETC) . ... ESO - Public Surveys . ... the recommended values to use for DIT, . ... Detector on-chip integration (DIT): seconds. to your chosen value - a separate page gives recommended values to use for DIT - for modes 1 and 2 below you may wish to start with the maximum recommended values as these will minimize the effect of read noise (a total object exposure of Y secs with DIT=X secs will produce Y/X lots of read noise) and give you a lower limit on the time needed. ...

... Meta Index / Home Page / Description This version of r mfgen supports all commonly used observing modes (Table 1 ). The mode is obtained from the keyword SUBMODE in the primary header of the input spectrum. ... The PN response is different for each observing mode while the MOS response is equal in the window modes but varies due to threshold effects in the Timing and Burst modes. Table 1: Observing mode support within r mfgen . ... Observing Mode . Support . ... FullFrame . Yes . ...

... Does the time it takes different methods to create all the elements coincide with the universeт??s accepted age? ... Illinois Urbana-Champaign) Different kinds of stars create elements at different rates, all of which are consistent with the age of the universe. Get instant access to subscriber content on Astronomy.com! ... Registration is FREE and takes only a few seconds to complete. If you are already registered on Astronomy.com, please log in below. ...

... An ionospheric trough is a region of decreased F layer plasma density. ... It is quite typical to make a distinction between the sub-auroral troughs at mid-latitudes, and high-latitude troughs within the auroral region or polar cap . ... working for mid-latitude trough and some types of high-latitude troughs, like the polar hole . ... Collis, P. N., and I. HДggstrЖm, Plasma convection and auroral precipitation processes associated with the main ionospheric trough at high latitudes, J. atmos. terr. ...

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. ...

... The following charts/text are intended as tools for monitoring the Type Ia supernovae ( SNe ) event visually or photographically (utilizing telescope equipped CCD equipment).The files include: A replication of The Type Ia SNe , V- magnitude (with data point checks from other cited references)and color index (B-V) templete (to indicate a general color-related trend of the type Ia ... I believe this might help alleviate some of the problems involving the making of acceptable amateur light curves...

Next: Radial velocity of the Up: Optical spectrum of IRAS04296 Previous: Observations and spectra reduction . ... However, molecular emission features are only very rarely observed in the optical spectra of PPNe. ... On the other hand, it is well known that cometary nuclei spectra show prominent Swan band emission. In both spectra of IRAS04296 we have discovered strong emission in the (0;0) and (0;1) bands of the Swan system of the molecule. ... Now consider the case of IRAS04296. ...

... Hale-Bopp and the Plateau de Bure Interferometer . ... Credit: A. Rambaud, IRAM team, France Explanation: Comet Hale-Bopp is being observed by many different telescopes. ... These telescopes are being used to detect the presence of different molecules in the coma and tail of Comet Hale-Bopp. ... The abundance of different types of molecules in Comet Hale-Bopp 's coma give clues to its composition and history, as well as clues to the composition and history of our Solar System . ...

... Under certain conditions, like those in the nucleus of a QSO, all atoms can be made to emit light at particular wavelengths. ... If that source is approaching the observer, the wave is squashed up onto itself making the wavelength shorter. ... This is redshift. ... You can see how the section of the QSO spectrum which we observe changes with redshift. ... We then see how far we had to slide the observed spectrum along the scale to make it match and that is the objects redshift. ... The 2QZ team . ...

... The first task assumes the searching for chemical composition and sizes of particles which give the wavelength dependence of the extinction efficiencies close to the observed dependence of . Figure 7: Wavelength dependence of the extinction efficiency factors for homogeneous spherical particles of different sizes consisting of astronomical silicate and amorphous carbon. The dashed segment shows the approximate wavelength dependence of the mean galactic extinction curve at optical wavelengths. ...

... A star was observed at different zenith distances during one night at the Engelgardt's Astronomical Observatory in the program of atmospheric extinction study at blue. ... The determination of the star's brightness was performed with the method of photon counting. ... Variable star. ... The brightness of the variable star was measured occasionally during the other nights, and moments of maximal values of brightness (15.59m) were received on nights 2­5, the 2nd table. ... JD 2452805. ...

... During the analysis of the surveys carried out on RATAN-600, it was found that almost one fifth of the detected sources shows significant radio flux variations. ... We used the data from "Cold" radio surveys carried out with RATAN-600 in 1980-1994 to search for radio sources with significant flux variability. ... On possibility of detection of variable sources using the data of Cold surveys carried out on RATAN-600. ... Detection of Variable Sources Using the Data of "Cold" Surveys. ...