... The absolute flux calibration of NICMOS will be calculated from observations of standard stars with known flux distributions F( ). ... In order to expand the set of IR standard stars in the appropriate flux range for NICMOS, M. Rieke, R. Thompson, and collaborators at the University of Arizona are making photometric observations of solar-analog stars, which will be used to normalize the solar spectrum to the observed IR magnitudes. ... Relative flux references accurate to 1.5% for standard...

Next: Airmass Calculation Up: Flux Calibration Previous: Flux Calibration . To calibrate the chromatic response, observations of a standard star (preferably more than one) are needed, for which the absolute fluxes are known. The spectral response curve of the instrument can then be determined with the command RESPONSE/LONG , and absolute fluxes for the objects of interest are obtained with CALIBRATE/FLUX . ...

. Next: Ground calibration Up: RGS_LINCOORD Previous: Purpose Contents . As the RGS is a dispersive instrument, where the wavelength of an event is determined by the position at which it strikes the detector following grating reflection, accurate knowledge of the instrumental geometry is fundamental. Grating geometry is held in header keywords; and the geometry of individual CCD detectors in the binary table. Michael Smith 2011-09-20

... User Guide ] Task: moment Purpose: Calculate moments of a Miriad image. ... Key: in The input image. No default. ... Key: mom -3: Velocity at peak intensity using a three-point quadratic fit around the peak (km/s). 2: Peak intensity using a three-point quadratic fit (units same as individual channels). ... The moments are calculated independently for each pixel using spectral channels with intensity satisfying the specified clip range. ... Key: axis Axis for which the moment is calculated. ...

The ESA/ESO Astronomy Exercise Series 2 . The Distance to Messier 100 as Determined by Cepheid Variable Stars . ... The small variations in distance to the individual Cepheid variable stars in the Cloud are negligible compared with the much larger distance to the SMC. ... In this way Cepheid variable stars can be used as one of the 'standard candles' in the Universe that act either as distance indicators themselves or can be used to calibrate (or set the zero point for) other distance indicators. ...

In the Table below the masses of some asteroids which were determined during the last years are listed. ... The listed values were determined from observations of many test bodies by the weighted least square fit for one perturbing mass and corrections to the orbit elements of all used test bodies. ... based on the observations of 98 asteroids (including 50278) with the values of standard error of mass determination less than 3.0 10 -11 M Sun . ... Mass . ... 3) Mass 121 : 0.74 x 10 -11 M Sun ; . ...

... The file names' construction . The flight (m) stage's file set . ... the orbital data used for the flight operation monthly (m) long-term planning, . ... The orbital calculations are based on the initial orbital data determined by KIAM RAN using the orbital radio- measurement treatment. The determined initial orbital data are presented as a state vector (satellite position and velocity) in the J2000 reference. ... Accept the file with extension '.bgr', where the Moscow time (MT=UT+3h) is used. ...

... When creating a mosaic from a set of individual frames, the correct background offset for each frame must be determined for proper matching. In this paper we describe a method for constructing a mosaic from a set of individual frames by applying a minimization technique. ... Typically these are frames with some known defect (see ? ... Determining which frames to exclude from the final mosaic is critical, since one bad frame can create background offset errors that propagate throughout the mosaic. ...

... Reference ID: ACTS . Driver ID: NIST_ACTS . ... This driver supports the NIST Automated Computer Time Service (ACTS). It periodically dials a prespecified telephone number, receives the NIST timecode data and calculates the local clock correction. ... In mode 0 the driver operates continuously at intervals determined by the fudge time1 parameter, as described above. ... Unlike other drivers, each ACTS call generates one clock correction and that correction is processed immediately. ...

These are very prominent absorption lines is most all galaxies. ... These pair of absorption lines will appear in all the spectra and they should be your principle source for determining the redshift. ... When this applet opens you will see an iconic representation of galaxies in the left hand side of the applet and a target area in the right side of the applet. ... Note: What you are doing in this excercise is identical to what Hubble did in the 1920's and you are using the same galaxies. ...

. This diagram shows a small table with three transparent cells and illustrates how their final background is determined. The table consists of two rows. Four (labeled) cells lie in the first row, but the second cell spans the first and second row. The first, third, and fourth cells of the second row are "empty". Each non-empty cell has a red background and a double black border. Each empty cell has the table's background color (specified as #ff0) as its own. Return to image.

THE PHOTOMETRIC RESEARCHS OF THE MERCURY'S SURFACE BY MEANS OF DIGITAL MODELS. ... The surface brightness of Mercury was measured Danjon (1933, 1949, 1953) and Harris (1961) in phase angle 3o-123o. The analysis of the various data of the integral photometric gives the results of determination of the main photometric constants for Mercury. ... THE PHOTOMETRIC RESEARCHS OF THE MERCURY'S SURFACE: S.G. Pugacheva The surface brightness of the Mercurian images was established on the geologic map Mercury. ...

... The evolution of a binary system is considered as a sequence of stages the duration of which are defined by the shortest evolutionary time-scale of one of the binary components (see the list of the evolutionary states of stars in Sections 3 and 4). ... Then the code finds a new stage the binary should transit to, with this stage being determined by the evolutionary states of both components, and calculates it. ... However, one can use the algorithm described above to model their evolution. ...

... Armagh Observatory, College Hill, Armagh BT61 9DG, +44 (0)28 3752 2928 . ... We discuss the diagnostic potential of high cadence ultraviolet spectral data when transient ionization is considered. ... The ionization fraction of the transition region ion O v and in particular the contribution function for the O v 1371 line are computed within the Atomic Data and Analysis Structure, which is a collection of fundamental and derived atomic data and codes which manipulate them. ...

Welcome to K -corrections calculator, simple service allowing one to determine K -corrections of a galaxy, given its redshift and one or more colours. ... K -correction in choose filter.. ... Redshift . Colour choose colour.. Colour value . Calculator . ... calculate spectral energy distributions , K-corrections calculator , GALEX FUV NUV , UKIDSS YJHK , K-corrections of galaxies , spectral based k-corrections , SDSS filter set K-corrections , K correction code IDL , kcorrect IDL C , . ...

... Shortly after its discovery it was determined to be in a highly elliptical path near Jupiter and on a collision course. ... T he size and mass of the original body and the individual fragments is as of this writing still highly uncertain. ... B etween 16 July 1994 and 22 July 1994 the fragments impacted the upper atmosphere of Jupiter. ... T he pictures were posted to the Net within hours of the impacts and caused severe overloading on some ftp and WWW sites. ... JPL's SL9 page . ... Small Bodies .....

Next: Infrared Data Up: Contents Previous: Optical Photometry . ... For example, one method is to derive the spectral energy distribution (SED) for a target star and compare it to the SED of a dereddened standard star. ... Temperature can be determine via the B - V color (Gilliland 1985): . ... The results produced small extinctions to the background stars of between A and A . ... The most accurate extinction calculation requires both IR and spectral data. Infrared Data . Spectroscopic Data . ...

Halley's Comet . Spacecraft that have visited Halley's Comet . ... Then in 1984 and 1985, five spacecraft from the USSR, Japan and Europe were launched to make a rendezvous with Halley's Comet in 1986. ... This image is a mosaic of 8 images taken by the Giotto spacecraft during the Halley encounter on March 13, 1986. ... Courtesy NASA/JPL) . ... Halley's Comets in 1986 . This image of Halley's Comets was taken during its 1986 appearance. ... Cylindrical Map of the Nucleus of Comet Halley . ...

... Resolved Stellar Populations Globular Clusters . Galaxies are made of stars, gas and the illusive dark matter. ... Star clusters are the simplest form of the stellar population. ... Old globular clusters are easily observed at great distances and can be used as probes of the early stages of star formation history in galaxies where individual stars cannot be resolved. My research interests are centered on the studies of resolved stellar populations and (old) star clusters in nearby galaxies. ...

Contact with possible Extraterrestrial Life . Recommendation for the human Contact Team to Interact with Unknown Life Forms . Contact teams meeting an Unknown Life Form must be prepared for severe psychological impact. Extreme anxiety response will almost certainly occur. The personality traits of individuals who can withstand extreme anxiety must be determined and such individuals selected to comprise the team. ... Contact team report. ... Our Contact team continue investigation. ...