... 12c. Venus transit (1) . 12d. Venus transit (2) . 12e. Venus transit (3) . ... 1 The 2004 Venus transit . ... Kepler's third law allows one to evaluate the dimensions of the solar system in relative units, e.g. in " astronomical units " (AUs), where 1 AU is the mean Sun-Earth distance. ... Edmond Halley suggested using the transit of Venus across the Sun's disk, when it appears as a dark round spot --or to quote one observer of the 2004 transit, "like a blueberry in front of an orange." ...

... 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. ...

... The routine returns the offset (deltaX, deltaY) from the linear grid position for a specified detector location. ... the distortion (deltaX, deltaY) at the detector location (rawX, rawY) is derived from the distortion map stored in the extension FILTER-FilterId (e.g. FILTER-U, FILTER-V, FILTER-GRISM1 etc.) ... interpolate the extracted distortion points (RAWX_OFF ,RAWY_OFF ) and calculate the distortion (deltaX,deltaY) at the requested postion (rawX, rawY) . ... deltaX, deltaY . ...

Russian version of HP . ... StarCalc is the fastest professional astronomy planetarium & star mapping program for Windows 9x/ME/NT/2000/XP (StarCalc version for PocketPC computers you can found here ). ... Extensibility : This program is based on common "Plugin StarCalc interface to catalogs and object groups", which allows program to add new modules as Plugins. ... Welcome to the Pocket StarCalc Home Page: . ... Some bugfixes in eclipses" and line" plugins - see the new versions in downloads page. ...

... Gauging the impact of executing science program across different COS/FUV lifetime positions . ... Changing Programs & Resolving Problems . ... The first such move occurred on 23 July 2012, when the COS FUV spectrum was moved to the COS FUV Lifetime Position 2 (LP2). ... It now appears that the move to COS/FUV Lifetime Position 3 will not occur until early 2015, and so a substantial fraction of Cycle 22 observationsare likely to occur at the COS FUV lifetime position 2, prior to the change. ...

... 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. ...

SAI 175 anniversary . ... Moscow University . Search for in SAI Moscow University Search for in Russian astronomical resources . ... SAI Astronomical Databases . ... Browse SAI Software archive(ftp.sai.msu.su) . ASTRONET.RU - Russian Astronomical Network (available in translit also) . ... SAI Supernovae Research Group . ... Department of the Galaxy and Variable Stars (in Russian) . Sternberg Astronomical Institute Seminars . ... All-Russian Astronomical Olympiad (in Russian) . ...

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. ...

... There is an opportunity to perform O-C calculations for objects which are absent in the data base of the package. Such objects can be described by orbital elements or by initial coordinates and velocities. ... On pressing Edit file button user has a possibility to look through the list of object elements or their coordinates and velocities to add or to change it. ... For example, the designations of objects in the list can occupy the last position in each line. ...

Pulkovo NEO Page . ... NEA Accuracy Estimation . ... The estimation of accuracy of the current CCD observations of asteroids and comets is constantly performed at Pulkovo Observatory. ... The (O-C) values, so called "Observed" minus "Calculated" positions, characterize numerically the observations of any observatory, both professional and amateur, during a short period (one or several close nights). ... So the (O-C) values for these objects nearly entirely define the errors of observations. ...

... Like the night sky on the Earth, the martian sky hosts a plethora of astronomical phenomena occurring around the clock in a neverending space opera played out for the benefit of robotic and future human observers alike. ... Moons . Mars has two moons, Phobos and Deimos . ... Under the same conditions, Deimos would be as bright as -5, somewhat brighter than the planet Venus appears in Earth's sky. ... The moons are also eclipsed by Mars itself (a situation analogous to lunar eclipses at the Earth). ...

... ARTICLE: The Adventurous Search For The Astronomical Unit . ... Kepler himself had suggested to use the rare occasions of Venus transiting (crossing) the solar disk to measure our distance to the planet. ... Due to the orbital inclination of Venus against the ecliptic of 3.5°, a Venus transit is so rare that it happens only at intervals of 121.5 years, 8 years, 105.5 years, 8 years and so on. ... Crabtree witnessing the transit of Venus 1639 . ... Transits of Venus - The Quest for the Solar Parallax...

... ATNF Home . About ATNF . ... About ATNF overview . ... Australia Telescope Steering Committee . ... Australia Telescope User Committee . ... Murchison Radio-astronomy Observatory . ... Parkes radio telescope . Australia Telescope Compact Array . Mopra radio telescope . ... Australia Telescope Online Archive (ATOA) . ... ATCA | ... Australia Telescope 20GHz Survey . ... Visiting Parkes radio telescope . Visiting Australia Telescope Compact Array . ... Parkes radio telescope webcam . ...

... The greater the distance, the smaller the parallax. ... That triangle has the same proportions as the much larger triangle ABC, and therefore, if the distance B'C to the thumb is 10 times the distance A'B' between the eyes, the distance AC to the far landmark is also 10 times the distance AB. ... The most distant objects our eyes can see are the stars, and they are very far indeed: light which moves at 300,000 kilometers (186,000 miles) per second, would take years, often many years, to reach them. ...

... Fitting the observed dependence includes calculations of the polarization cross-sections averaged over particles orientation and size distribution, their normalization and the comparison of obtained dependencies with Serkowski's curve representing observational data for a chosen star. ... Variations of the polarization factors with wavelength are shown in Fig. 16 for homogeneous spheroidal particles with PF orientation. ... The distinction between prolate and oblate spheroids is also clearly seen. ...

... We publish 16 Doppler imaging temperature maps for the years 1994-2002 of the active RS CVn star II Peg. ... Through Doppler imaging we want to study the spot evolution of the star and in particular compare this with previous results showing a cyclic spot behaviour and persistent active longitudes. ... The derived temperature maps are quite similar to the ones obtained earlier with a different methods, the main differences occurring in the spot latitudes and relative strength of the spot structures....

... 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. ...

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) . ...

... Dr. Rodrigues, M1 group, Spain, has pointed out the confusion in identification of SN 1998ar in NGC 2916. ... I have measured the locations of point-like sources around NGC 2916 with DSS-1 image and 5 GSC stars. ... The magnitude of this star is estimated as 15.5 mag or so on DSS1 image. ... Star C seems to be dimmer than Star B, and comparing GSC 14.8 mag star and fainter neighbouring stars, its magnitude is about 1.5 mag dimmer than GSC 14.8 mag star; which tells that SN was about 16.3 mag. ...

Why are there different versions of CIMA? Which version of CIMA should I choose? ... There is no CIMA log in my project directory --- what happened? ... If You are a normal, happy observer, You should choose the CIMA version with the highest version number, since that version contains the latest improvements and bug fixes. ... This means that programs like the data quick-look display and various ALFA instrument displays all exist in several versions just like the CIMA observing session itself. ...