... These are just the bare bones--just three basic ideas and rules for handling relations ("equations") involving unknown quantities whose values you are trying to find. In most calculations you try to find a number . ... To get a solution, one must replace the given equation (or equations) with others, containing the same information but cleaner in appearance. ... If you have an equation and modify both its sides in exactly the same way, what you get is also a valid equation. ...

Winer Observatory P.O. Box 797, Sonoita, Arizona 85637-0797, USA . ... Site . Weather . Roof Status . ... Average Max. ... 0.0 . ... In 2004, the roof was operated manually, while in 2005 through 2007, it was operated automatically by computer, but was not closed by weather sensors. ... The "Closed" column includes those nights outside the Monsoon season when the Observatory was closed due to weather (the usual cause), equipment failures, or vacation by the Winer staff in 2004 through 2006. ...

... To save time, I will only provide ephemerides in 2000 coordinates. ... Note: most the orbital elements used to create these ephemerides were obtained from the International Astronomical Union Circulars (IAUCs), Minor Planet Circulars (MPCs) or the ICQ Comet Handbook. ... The following 1-day ephemeris (March 1, 1997 - October 1, 1997) is from Donald Yeomans of JPL and is based on Reference Orbit #55 (March 4, 1997). 2000 coordinates (March - September, 1997) [3/4/97] . ... Epoch: 1997 Feb. 1.0 . ...

... CI ) - Cm (I )) ( = 2 (I) N 2 2 PKS0558-504 simultaneous fitting The Chi-Squared is the most common statistic in use to fit a function f to data {x, y} : = 2 N ( yi - f ( xi )) 2 2 i N = number of data points i2 = variance (related to the measurement error for yi ) y = independet variable x = dependet variable f = assumed relationship between x and y yi = observed mean f(x i ) = predicted mean Statistical concepts relevant to data ... 2 * < 1 { (I) OVERESTIMATED} BAD FITTING!! ...

Once students get the hang of it, they can find and measure the brightness of Delta Cephei in a few minutes. ... of Delta Cephei . ... Oct. ... The following table lists the measurements of Delta Cephei made by one amateur astronomer in autumn 1990. ... 4.0 . ... This activity is a simplified version of one that appeared in Hands-On Astrophysics, a series of activities prepared by the American Association of Variable Star Observers with support from the National Science Foundation. << previous page | ...

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HIGH MASS X-RAY BINARIES AND RECENT STAR FORMATION HISTORY P. Shtykovskiy 1 1,2 and M. Gilfanov 2,1 Space Research Institute of Russian Academy of Sciences, Moscow, Russia 2 Max-Planck-Institut fur Astrophysik, Garching b. Munchen, Germany Ё Ё ABSTRACT Based on the XMM-Newton observations of Magellanic Clouds we consider the dependence of population of high mass X-ray binaries on the recent star formation history in the host galaxy. ... HMXBS AND RECENT STAR FORMATION IN MAGELLANIC CLOUDS 4.1. ...

... Tonight's Sky . ... The Magazine . ... Observing . ... Gravitational wave search provides insights into galaxy evolution and mergers . ... The double star 54 Leonis, spiral galaxy NGC 3198, and emission nebula NGC 3199 . ... Astronomy for Kids . ... Imaging Basics . ... The right number of images . ... Get instant access to subscriber content on Astronomy.com! ... Receive news, sky-event information, observing tips, and more from Astronomy's weekly email newsletter. ... Astronomy Magazine . ...

ChaMP and the High Redshift Quasars in X­rays S. Mathur 1 Harvard Smithsonian Center for Astrophysics Cambridge, MA 02138 H. Marshall 1 MIT, Cambridge, MA 02139 N. Evans 1 , P. Green 1 and B. Wilkes 1 Harvard Smithsonian Center for Astrophysics Cambridge, MA 02138 Abstract. ... This will enable us to determine the high redshift X­ray luminosity function. ... Prediction of Redshift Distribution of Quasars in ChaMP Fields The X­ray Luminosity Function at z = 0 is described as \Phi(L X ) = \Phi ? ...

... a journal of his thoughts and experiences, some two million words in . ... The boy's sled gets put away in the barn or shed, and there it lies . dormant all summer, like a woodchuck in winter. ... sees a sled, nor a sled a woodchuck, unless it were a prematurely risen . ... Journal, 25 March 1860 . ... Please join us for a pre-meeting dinner discussion at Changsho, 1712 Mass Ave, Cambridge, MA at 6:00pm before the meeting. ... Copyright (c) Amateur Telescope Makers of Boston, Inc. ...

. | Front page | . | << - Number Counts | . Robert J. Smith, ">rsmith@mso.anu.edu.au Last modified: Fri Sep 24 11:39:02 EST 1999 .

... 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. ...

Download Izmccd (~2.7 MB). ... for 1-5 bytes is number of a numbered minor planet, . ... Positions 1-80 file "mpcreportiz.txt" are similar to positions of file "mpcreport.txt". 83-95 – errors of unit weight, . ... If this tag is " 1 0 " , this record contains results of measurements of an image of object (approximation by "PSF"),  . ... 57-66 – error in X (pixels), for first star in a multicentric image, for subsequent it is error in (distance between first star in the image and this), . ...

... GCR and SCR are primary cosmic rays. 10-15 years after the discovery of cosmic radiation (1919) there emerged two main avenues of investigation in the physics of cosmic rays (CR): 1) nuclear - elucidation of the origin of elementary particles and nuclear interactions; and 2) astrophysical (space physics) - solution of the problem related to the origin and variations (changes in intensity) of CR. ... Besides, the CR flux in interplanetary space is, strictly speaking, not isotropic. ...

... 28 April 2010 FTT kick-off meeting 5 Where are we today? Use results from this to secure funds for expansion post 2012 Majority of funds from NMT ­ possibility of some STFC support 28 April 2010 FTT kick-off meeting 6 The FTT /NAS system Ensures that the light beam collected by a telescope is sent down the beam relay pipes in the right direction The FTT /NA system monitors the light The active secondary mirror redirects it 28 April 2010 FTT kick-off ...

... Sun's ecliptical positions. Explanations. Each row contains at 0h of Time Dynamical Terrestrial: month, day , day of the week, julian day number at beginning of day (only last three digits is given, add head of column to form correct number ), longitude in system of mean equinox of date (degrees, minutes, seconds ), two latitudes (the first for mean equinox of date and the second for mean epoch of year; seconds ), radius-vector (astron. units), precession in ...

Large Sunspot Group AR 9393 . ... Credit Copyright: MDI , SOHO , ESA , NASA Explanation: The largest sunspot group of the past ten years crossed the surface of the Sun late last month and early this month. The group was designated Active Region 9393 as it was the 9393rd region identified since counting officially began in 1973. ... Will the above sunspot group remain as its region rotates back into view in a few days, or will it break up on the far side of the Sun? ... NASA Official: Jay Norris. ...

... Let us first find out which way -- rise in spectral resolution with some loss in the S/N ratio or increase in the S/N ratio with a fixed spectral resolution -- is better for the purpose of reduction of equivalent width determination errors. ... N -- number of counts for 1 ? ... line equivalent width, . ... Thus if the spectral resolution is managed to be increased (i.e. to decrease )without loss in the number of counts falling at 1 ?, the equivalent width measurement error is then proportional to . ...

... ON THE ROLE OF LARGE-SCALE PLASMA IRREGULARITIES AT THE FINAL STAGE OF ANOMALOUS ABSOPTION DEVELOPING UNDER HF HEATING OF THE IONOSPHERE . ... Fig. ... With the aid of numerical statistical modeling based on multiple ray tracing it is shown that in presence of large-scale irregularities the reflected signal amplitude mean value is increased significantly. ... Dependence of the mean amplitude of the reflected from the ionosphere signal on the large-scale (10-50 km) electron density irregularity level...

... 1.7 GSC 084 Pulkovo Obs., 0.33 15 x 15' 1.0" 7 34 0.179 0.307 Normal Asgr. 3.0 UCAC 118 Slovakia, 0.57 14 x 10' 1.7" 3 12 0.090 0.145 Modra 3.3 USNO 127 Germany, 0.19 30 x 20' 2.4" 3 15 0.151 0.087 Bornheim 0.8 GSC 168 34 200 0.282 0.315 291 USA,Kitt Peak, 1.8 390 x 30' 1.0" 1 5 0.143 0.144 Spacewatch II 4.7 USNO 300 Japan, 0.5 78 x 78' 2.3" 7 36 0.420 0.447 Bisei Center 1.3 ACT 461 Hungary, JATE 0.60 28 x 19' 1.1" 6 22 0.124 0.153 Asteroid Surv. ... Polynesia 1.0 UCAC F85 Tiki Obs., ...