... Team . ... The main goal of observations of GRB host galaxies is accumulation of statistics of their spectroscopic and photometric properties. ... The Hubble diagram for 22 GRB host galaxies with known magnitudes and redshifts (GRB 970228, GRB 970508, GRB 970828, GRB 971214, GRB 980613, GRB 980703, GRB 990123, GRB 990510, GRB 990712, GRB 9912008, GRB 991216, GRB 000131, GRB 000210, GRB 000301C, GRB 000418, GRB 000911, GRB 000926, GRB 001109, GRB 010222, GRB 010921, GRB 011121 and GRB011211). ... 600...

Next: Star Formation Rate and Up: No Title Previous: Calculation of Evolutionary Tracks . To start calculations, we choose the distributions of the initial binary parameters: the mass of the primary ZAMS component, , binary mass ratio, , orbital separation a . ... whereas the mass ratio distribution is not. ... The zero assumption often made is that the mass ratio distribution has a flat shape, that is binaries with a high mass ratio occur as frequently as those with equal masses. ...

... Telescopes ћ Binoculars ћ Microscopes . Binoculars Instruction Manual . ... Regardless of your application bird watching, nature studies, spectator sports or sightseeing you will appreciate the superior optics and durable construction that make Meade binoculars an excellent investment. ... FOCUS LOCK SYSTEM . Meade Safari Pro binoculars include a Focus Lock feature (see diagram), permitting the locking of the Center Focus Knob to maintain precise focus of an object at a specified distance. ...

Here user should specify the origin of coordinate system (observer's position). In case of rectangular coordinates it can be center of any major planet or the Sun or any minor planet. ... For spherical coordinates the origin of coordinate system can coincide only with the center of the Earth or with any point on the Earth surface. ... a)by code of observatory in the list of observatories maintained by Minor Planet Center (see IX. Observatories ). b)by introducing name of observatory. ...

Next: NICMOS/HST H-band (F160W) Images Up: NICMOS Science Previous: HST NICMOS Observations of . ... Observations of P . ... The NICMOS team has devised a comprehensive program of observations of the Galactic Center. ... Data in hand give a first look at variability and a detailed look at the search for the tip of the main sequence will be discussed where NICMOS has demonstrated adequate sensitivity and photometric precision to identify likely O8-B1 stars at the Galactic Center. ...

... Exposure Time Calculator (ETC) . Survey processing . ... VISTA is a 4-m class wide field survey telescope for the southern hemisphere, equipped with a near infrared camera (1.65 degree diameter field of view at VISTA's nominal pixel size) containing 67 million pixels of mean size 0.34 arcsec and available broad band filters at Z,Y,J,H,K s and a narrow band filter at 1.18 micron. A wide field visible camera, if constructed, could also be used on VISTA. ... Tile . ... ESO VISTA Public Surveys . ...

OBSERVATIONS OF COORBITAL SATELLITES OF SATURN Emel'yanov N., Varfolomeev M. Sternberg State Astronomical Institute, Moscow, e-mail : emelia@sai.msu.ru Institut de MИcanique CИleste et de Calcul des иphИmИrides, Paris, e-mail : emelia@imcce.fr Abstract. To improve the orbital parameters and masses of coorbital satellites of Saturn, Janus and Epimetheus, new observations of these satellites are necessary. ... IN: Saturn. ... New observations of Saturn's coorbital satellites" - Icarus. ...

Astronomy Discussion Forums . Forums: . ... TIME DILATION . ... Time dilation is what we take to be the disagreement in the total time of an event as measured by a moving frame and stationary frame. ... Imagine a car 100km from a stationary observer and which is positioned such that it would travel 200km on a straight line in a direction away from the stationary observer. ... Therefore the total time of motion of the car as measured by the stationary observer is T= t- 100km/C + (100km+200km/C). ...

... The Sun has come all of one day away from breaking its record for the longest period of inactivity for the last decade - reaching a mid-summer low and falling into yet another state of "hibernation". Yesterday, on the first day of autumn, new sunspots appeared on the surface of the Sun following an absence of almost 50 days. ... The first low lasted 51 days, from 21 July until 11 September last year. ... Now, almost a year later, it seems the Sun has hit a new low almost as "deep" as the first. ...

From Herschel's catalog, the first accurate stellar parallax measurement of 0.32 seconds of arc for the star 61 Cygni was published by the F.W. Bessel in 1838. ... This distance is equivalent to 3.26 light years. ... The Universe was now a large place and the intrinsic energy output of the stars had to be huge in order that their light could reach us. ... An Orbit in Curved Space This is a prediction made by General Relativity and confirmed by direct observation of Mercury. ...

Twilight observations with MASS/DIMM B. Safonov Sternberg Astronomical Institute Moscow State University Comprehensive Characterization of Astronomical Sites, 2010 B. Safonov (Moscow State University) Twilight observations with MASS/DIMM SITE 2010 1 / 17 Why observe in twilight with MASS/DIMM? ... ASM includes 3 devices sensitive to background: guider, DIMM and MASS. B. Safonov (Moscow State University) Twilight observations with MASS/DIMM SITE 2010 2 / 17 Background in guider. ...

... Laboratory and theoretical modelling of the UV bump on the interstellar extinction curve is a very popular topic in dusty investigations. ... feature is illustrated by Fig. 10 where the profiles were calculated using the model of graphite spheres. Figure 10: Normalized extinction efficiencies for graphite spheres. ... The lower panel shows the summary extinction of two graphite spheres with radii and (from upper panel) taken in equal proportions. ...

... They are concerned with Attitude Control System of the spacecraft, satellite visibility from tracking stations, limits on the satellite autonomous operations during the orbit, and needs for auxiliary operations with the spacecraft. ... Among the operational constraints the most important one is the number of programmed slews per orbit, which determines the maximum number of radio sources to be observed during one orbit. ... System temperature (K) . ... Progress of the RadioAstron Project in Pictures...

... From the chain visibility point of view, it is very recommended to look at the Javascript movies , especially if the frame rate can be not regulated in your MPEG player. ... The non-CH-associated large-scale chains visible on the SOHO/EIT images at three wavelengths of 171, 195 and 284 as well as on the MLSO/HAO He I 10830 spectroheliogram of December 16, 1997. ... The SOHO/EIT movies at 171 and 195 show the chain dynamics on June 1-3, 1998. ... Javascript movie (230 KB), SOHO/EIT, 171 . ...

The IAO-type events have to stimulte the science-educating style of the Olympiads. To follow the main science-educating principles of the IAO-type events and Schools for Young Astrophysicists , particularly: . ... The minimum duration of the IAO-type event is defined as 5 days (4 nights). ... foreign language teams for an international IAO-type event - 1 / 2. ... The full text of the current Supplementary Instructions N 4 IAO-type events and Schools for Young Astrophysicists to be presented later. ...

... The bright supernova (hereafter SN) in the galaxy NGC 4527 was first sighted by S. Knight (USA) on April 13.17UT at magnitude ~14.0v. The report of the sighting was subsequently forwarded by phone to the AAVSO. ... SN 1991T. The galaxy NGC 4527 is an Sb(s)II type galaxy with an apparent Blue magnitude of 11.32 (Shapley-Ames, 1981). ... An analysis of this event utilizing visual observations by amateurs, plus a light curve is presented.. ... THE LIGHT CURVE: . ... ISN SN 1991T web page . ...

... Tonight's Sky . ... SUN MOON MERCURY VENUS MARS, JUPITER SATURN . ... Observing . ... Why Join? ... Jupiter joins Venus in the early evening . ... That more brilliant one is Venus, and it s currently having its best showing for northern observers of 2015 as it shines brightest and appears highest in the evening sky. ... Only the Full Moon itself climbing higher in the southeastern sky this evening appears brighter. ... Only registered members of Astronomy.com are allowed to comment on this article. ...

... Spherical aberration, coma, and astigmatism are also easily observed using the star test. ... Off-axis images are complex. ... Fig. ... Diffraction by a circular aperture as a function of defocus for no aberration Airy Disk 1 wave defocus Less than 1 wave defocus Fig. ... Diffraction by a circular aperture as a function of defocus for third-order spherical aberration Paraxial Focus Small distance inside paraxial focus Moderate distance from marginal focus Immediate neighborhood of marginal focus Fig...

... Bad Astronomy . Misconceptions . ... Bad Astronomy : The Moon only shows one face to us because it is not rotating. Better astronomy : The Moon only shows one face because it is rotating, once every time it revolves around the Earth. ... Place the Moon model on the table about 30 centimeters (one foot) away with the X facing the Earth model. ... You'll see that to keep the X facing the Earth model, you have to rotate the Moon model as it goes around the Earth model . ... 2008 Phil Plait. ...

... Classes . ... Nebula Class Reference . ... getInfoString (const StelCore *core, const InfoStringGroup &flags) const . ... getCloseViewFov (const StelCore *core=NULL) const . ... getVMagnitude (const StelCore *core, bool withExtinction=false) const . ... getSelectPriority (const StelCore *core) const . ... getEquinoxEquatorialPos (const StelCore *core) const . ... getJ2000GalacticPos (const StelCore *core) const . ... getPositionInfoString (const StelCore *core, const InfoStringGroup &flags) const . ...