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. ...

We present a database of UV-to-FIR data of 83 nearby starburst galaxies. ... The NIR data are from new observations obtained at the NASA/IRTF and the Mount Laguna Observatory, combined with the published results from observations at the Kitt Peak National Observatory. ... In conjunction with IRAS and ISO FIR flux densities, all these data form a set of observed spectral energy distributions (SEDs) of the nuclear regions of nearby starburst galaxies. ...

... Within SAS, a tool is available to check the pile-up fraction in the pn data: epatplot . This tool compares the observed pattern distributions (derived from a pn calibrated and concatenated even list) with the calibrated models. ... The lower panel is the key element for the evaluation of the pile-up fraction: it shows the observed distribution of pattern as a function of energy (PI channel in Analog-Digital Units ), using the same color code. ... Pages maintained by SAS librarian . ...

... Armagh Observatory, College Hill, Armagh BT61 9DG, +44 (0)28 3752 2928 . ... While the traditional statistics of impact craters allow us to determine the cumulative meteoroid flux on the lunar surface, the recent successful identification of fresh craters in orbital imagery has the potential to directly measure the cratering rate of today. Time-resolved recordings, e.g., seismic data of impacts and impact flash detections clearly demonstrate variations of the impact flux during the lunar day. ...

Next: The derived luminosity and Up: The galactic population of Previous: The galactic population of . Figure 16: The observed distribution of pulsar dispersion measures. Dotted curve is the total known population, solid curve is the Parkes survey. Figure 17: The observed distribution of pulsar distances above the galactic plane. ... Figure 18: The observed distribution of pulsar flux densities. ...

... The resulting spectra were analyzed with a kinematic Monte Carlo model which allows estimation of the OH production rate, neutral gas outflow velocity, and distribution of the out-gassing from the nucleus. ... The best-fit model spectrum is shown together with the observed line. ... Both models are scaled to match the average off spectrum. When the same scaling is applied to the nucleus-centered model spectra, shown on the right, it is clear that only the quenched model matches the observations. ...

Short-Period Comets: Origin and Terrestrial Impact Hazard . ... The model is consistent with the basic observed distributions of near-parabolic comets, short-period comets, Centaurs and high-eccentricity trans-Neptunian objects.This model requires that initial objects in the early Solar System are concentrated to the outer planetary region, and the physical lifetime of comets in the inner planetary region at the present epoch is an increasing function of initial perihelion distances. ...

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. ...

Diffuse interstellar bands (DIBs) and atomic lines are observed as interstellar absorptions in GALAH and other massive spectroscopic stellar surveys. By observing a given DIB toward many stars which are nearly in the same direction, but at different distances, one can reconstruct absorption sites along the line of sight. ...

Educator's Guide to Impact Craters . ... Just about all craters have deep central depressions, raised rims, and a blanket of ejected material surrounding them. ... Look for classical cratering features: basin, raised rim, ejecta blanket (material excavated from the crater and dumped around it, visible as white flour on the colored powder), and rays (material shot out at high velocity forming lines pointing directly away from the impact site). ... The material lies like a blanket around the crater. ...

http ://hea-www.harvard.edu/ AstroStat /slog/2008/eotw-chisq- distribution / Weaving together Astronomy+Statistics+Computer Science+Engineering+Intrumentation, far beyond the growing borders Fri, 01 Jun 2012 18:47:52 +0000 hourly 1 http ://wordpress.org/?v=3.4 http ://hea-www.harvard.edu/ AstroStat /slog/2008/eotw-chisq- distribution /comment-page-1/#comment-308 Alex Sun, 27 Jul 2008 01:52:08 +0000 http ://hea-www.harvard.edu/ ... Thanks, Aneta, very useful comment. ...

... Up: Proposal Processing . ... ESO is prototyping a distributed ``Phase II'' system that will allow astronomers to prepare their observations at their home institutions, while maintaining a central repository for all observation data. ... ESO is developing a Phase II Proposal Preparation system (P2PP) to collect detailed scientific programme descriptions, in the form of observation blocks (OB). ... ESO's Phase II Proposal Preparation system is an integral part of the VLT Data Flow System (DFS). ...

... Our resulting sample of ELGs presented in Tables 2 and 3 is not artificially biased to any specific type of galaxies. ... Since we are looking for selection of a sample of Case BCGs, it is interesting to examine how the detected BCGs are connected with Case emission-line codes. ... Altogether BCGs comprise about 60 % of all Case ELGs which display emission lines in our spectra, or about 44 % of all Case galaxies with some emission-line code. ... Among those with the code ``w'' about 40 % are BCGs. ...

... St Petersburg 23, September 2014 1 Motivation · Origin of Martian moons? ... Considered error sources: ­ Phobos a priori ephemerides; ­ Phobos a priori GM value; ­ measurements noise; ­ different strategies; · Methods: ­ real data analysis; ­ simulations. ... St Petersburg 23, September 2014 8 Simulations: sensitivity of the measurements to the a priori GM value Simulations: zero noise+ IMCCE a priori ephemerides +GMPH = 7.16 * 105 m3/sec2. ... St Petersburg 23, September 2014 14 Thank you! ...

... 2001 December 8 . Moon Struck . ... Explanation: Craters produced by ancient impacts on the airless Moon have long been a familiar sight . But only since 1999 have observers seen elusive optical flashes on the lunar surface - likely explosions resulting from impacting meteoroids. ... Six confirmed flashes, some initially as bright as a third magnitude star, were all seen within hours of the peak of the 1999 shower. ... About APOD | ...

SWIRL DISTRIBUTION ON THE LUNAR SURFACE: LOCATIONS ANTIPODAL TO THE YOUNG BASINS? ... There are two main classes of hypothesises of the swirl origin: formation of the swirls in the regions antipodal to large impact basins (1), and formation of the swirls in result of cometary impacts (2). ... The Orientale basin is youngest. ... Fig. ... On the other hand, there are two cases of absence of correlation between swirl areas and regions antipodal to impact basins (for small swirl formations). ...

Crater Gassendi . ... I made this drawing was made on the 26th of november 2001. If you compare this one with the previous drawing of Gassendi (below) the differences are clear. ... This drawing was made on the 28th of september 2001. After nearly a full month without observations I had a one hour gap between the thicker clouds. ... This drawing was made on the 29th of august 2001. ... This drawing was made on the 27th of august 2001. ... This drawing was made on the 25th of august 2001. ...

... Carefully measure the diameter of the craters formed by the impact without disturbing the sand. ... Crater diameter increases with increasing mass. ... Without disturbing the sand, carefully measure the crater diameter. ... Did you measure any difference in the diameters of the craters? Yes, as velocity increases, so does crater diameter. ... Impact cratering. ... Impact craters can be demonstrated with younger or less advanced students using mud instead of sand and ball bearings. ...

... According to the most popular cosmological paradigm, the greater part of the galaxy mass is accumulated in the dark matter halo. ... The polar ring galaxies (PRGs) reveal external rings or disks of gas, dust and stars rotating in a plane roughly perpendicular to the disk of the central galaxy. ... The shape of the dark halo in the model was chosen so as to achieve the best fit to the observed rotation of both galaxies themselves and their polar rings. ... The SPRC-7 galaxy. ...