Next: Young Energetic pulsars Up: A Tutorial on Radio Previous: The population of millisecond . Assuming a thin-screen model, calculate the apparent angular diameter of the Crab pulsar at 600 MHz. Assume that the apparent angular diameter = 100mas at 100 MHz. Calculate the apparent angular diameter at 600 MHz if the screen is located at 1% of the distance from the pulsar to the Earth. ... Calculate the parallax's for pulsars with distances of 100, 500, 1000, 5000, 10000 parsecs. ...

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• PULSE@Parkes Assumed Knowledge and Skills
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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. ...

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• Initial binary parameters
• Discussion and conclusions
• Binary Pulsar Diversity and High Neutron Star Birth Velocity

... We present a computer program for modelling energy flux distribution and light curves of eclipsing binaries from far ultraviolet to infrared regions. The Roche model is assumed. Proximity effects of components (reflection of radiation and surface gravity darkening) are taken into account. ... Figure 1: The surface temperature distribution for Algol A-B system before (upper plot) and after (lower plot) correction for temperature due to the irradiation effect. ...

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• Identification and Analysis of Binary Star Systems using Probability Theory
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• The Time Interferometer: Synthesis of the Correlation Function

... 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. ... Newton implicitly assumes space is flat . ... An Orbit in Curved Space This is a prediction made by General Relativity and confirmed by direct observation of Mercury. The Ant Universe in Flat Space . ... Hubble noticed a correlation between recessional velocity and distance. ...

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... Correcting ETC Calculations of CCD Spectral Observations for CTE Effects . ... HST Overview . Overview . ... Post-Observation . ... ETC . ... ID: CL Script for Applying CTE Loss to Output of Spectroscopic ETC . ... However, the STIS ETC calculations do not incorporate these CTE effects as yet. ... The output from this script should then be used to calculate the appropriate input flux level for a second run of the ETC, which will then yield output which is corrected for the CTE effect. ...

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Astrophysics 405 Homework Assignment 4 Tully­Fisher Galaxies in the Expanding Universe Due 1999 April 15 This assignment is a ``dry lab'' simulation of a galaxy observation project. ... Images, spectra, and apparent magnitudes mB for a collection of nearby galaxies have been provided. ... For those galaxies you are unable to classify, assume type Sc. (g) Compute the T­F distance for each galaxy. ... 2 Galaxy Data Use the following data in your calculations. There are 32 galaxies in this sample. ...

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• http://www.naic.edu/~gibson/asph405/dry/drylab.pdf
• AO radar on hartley
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Astro193 Homework 11 due on April 27, 2015 Periodogram exercise Generate 50 random data points Y(t) assuming a periodic model for the signal: Y (t|P ) = 42.0 + sin (2 t/P ) with a period P = 0.4 day and the time t nonevenly spaced over the total duration time T of: a/ T1= 5 days, b/ T2=10 days c/ T3=30 days. ... 2/ Calculate Nyquist frequency for each observation. 3/ Calculate a periodogram for these data using LombScargle algorithm (you can use the code available in R, IDL or Python SciPy). ...

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• Chandra Images for G008.3+00.1
• Vertical Structure of the Secondary: Hydrostatic Model
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... This will be done by fitting period-luminosity relations in the form V = a в log P + b to Cepheid variables in these two galaxies. ... 8 Marks 2. ... 3R x3 2 Marks (b) Use this expression for the pressure to show that when 1 is constant, the adiabatic wave equation for the star can be written as x d d 3 R3 2 3 [(x - x4 ) ] + [ x - (31 - 4)] = 0. dx dx 1 GM 2 Marks (c) Show that near x = 0, the solution to this equation is of the form = Ax , where A is a constant and 2 = 3 (31 - 4). ...

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• http://www.mso.anu.edu.au/~brian/A3002/probset2-2008.pdf
• http://www.mso.anu.edu.au/pfrancis/ObsTech/Ass4.pdf
• http://www.mso.anu.edu.au/~brian/A3002/probset2.pdf

... The first EGRET catalog ([ Fichtel et al. 1994b ]) used the galactic diffuse gamma radiation model of Bertsch et al. (1993b). ... For the results presented by Bertsch et al. (1993b), the HI and W radio data were deconvolved by integrating the radio data over a velocity interval determined by the endpoints of each distance interval ( ). ... The Galactic radius limit used in the model has been increased to 30 kpc. ... The CR electron spectrum of Fichtel et al. (1991) was used by Bertsch et al. ...

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• Source Positions
• Catalog Construction
• Period analysis

The fundamental role of the Oort cloud in determining the flux of comets through the planetary system . ... 1000 au) during their dynamical history. ... Objects that have visited the Oort cloud represent a substantial fraction of the Jupiter-family comet population, achieving short-period orbits by a process of gradual dynamical transfer, including a Centaur stage, from the outer Solar system to near-Earth space. ...

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... Bojan Nikolic web pages (r. 329) . ... From astromap version 1.5b3, the OOF software supports deconvolution of an observation of a planet to retrieve the assumed Gaussian parameters of the beam. This deconvolution can be useful for empirical monitoring of telescope beams over time over which the planets used as sources vary significantly in size. ... Bojan Nikolic <b.nikolic@mrao.cam.ac.uk> # Initial version 2005. ... Copyright 2005 -- 2016, Bojan Nikolic feedback welcome ...

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By using the tools of sections (20) and (21), the mathematics of approximate solutions developed in (M-5), and assuming all orbits are circles, it is a relatively straightforward job to calculate the distance to the Lagrangian L1 point (or to L2). ... Let the gravitational constant be denoted by G , the mass of the Sun by M , that of Earth by m , the Earth's distance from the Sun by r and its velocity in its orbit by v . ... GMm / r 2 = mv 2 / r . and multiplying both sides by r / m . ...

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• How distant is the Moon?
• The Moon's Distance--Another Way
• Newton's theory of "Universal Gravitation"

... By using the tools of sections (20) and (21), the mathematics of approximate solutions developed in (M-5), and assuming all orbits are circles, it is a relatively straightforward job to calculate the distance to the Lagrangian L1 point (or to L2). ... Let the gravitational constant be denoted by G , the mass of the Sun by M , that of Earth by m , the Earth's distance from the Sun by r and its velocity in its orbit by v . ... GMm / r 2 = mv 2 / r . and multiplying both sides by r / m . ...

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• How Distant is the Moon?--lesson plan #14
• Parallax--Lesson Plan #14
• Two points (INTERBALL-1 and MAGION-4) observations of magnetopause motion

... 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...

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This is a copy of a Press Release from E.S.O. Eight years after the passage of Comet Halley in early 1986, astronomers at the European Southern Observatory have succeeded in obtaining an image of this famous object at a distance of no less than 2,820 million km from the Sun. ... The image shows the 6 x 15 km avocado-shaped nucleus as an extremely faint point of light without any surrounding dust cloud. ... This observation was made with the ESO 3.58 metre New Technology Telescope (NTT). ...

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• ESO - Science Announcements
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... Proximity e#ects of com­ ponents (reflection of radiation and surface gravity darkening) are taken into account. ... As an example, we consider the Algol (# Persei) system, where an eclipsing pair (Algol A­B) is accompanied by the third component (Algol C). ... The surface temperature distribution for Algol A­B system before (upper plot) and after (lower plot) correction for temperature due to the irradiation e#ect. ... We solve this equation by the iterative Newton­Raphson method. ...

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• HST/NICMOS Observations of the Interacting System Arp 299

SAS home . ... List of SAS threads . Let us assume we are working in /home/user/my_work and have our XMM observation data files in /home/user/sasdata/ <my_obs>, where <my_obs> identifies a specific XMM observation. ... 2) Where are stored all the Calibration files? ... That is done by creating a Calibration Index File ( CIF ) which will tell our reduction processes which CCF s we need to use out of all available in SAS_CCFPATH , for the specific date of our observation data. ...

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Physical and dynamical parameters of particles in outbursting Comet 17 P/Holmes . ... The time depending offset between the center of brightness and center of mass of the comet nucleus has been determined on the ground of positional observations of the comet. ... The motion of these particles allowed subsequent offset between the center of brightness and center of mass of the comet nucleus to be obtained from positional observations. ... comet, dynamical model, outburst, brightness. ...

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• AY (contents)
• AY2016 (contents)
• AY2011 (contents)

The Arcetri Spectral Code (Landi and Landini 2002) allows to evaluate the spectrum of continuum and line radiation emitted by hot and optically thin plasmas in the spectral range 1-2000 Angstrom. The Code is composed by a large database of atomic data and transition probabilities for calculating spectral line emissivities and a suite of fortran programs able to evaluate free-free, free-bound and two-photon continuum radiation. ... Landi, E., Landini, M., 2002, A , 384, 1124 . ...

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• The Arcetri Spectral Code - E.Landi and M.Landini (1998)
• A Hubble diagram for Quasars
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Astronomy Discussion Forums . ... God and Science ћ SETI ћ Software ћ UFO ћ XEphem . ... SETI Assumes ET Doesnot Care About Can Being Detected What If . ... Post Message | ... My search on how to go undetected in space and SETI Search for Extraterrestrial Intelligence SETI. ... www.astronomy.net . About Astronomy Net | Advertise on Astronomy Net | ... Forum posts are Copyright their authors as specified in the heading above the post. "dbHTML," "AstroGuide," "ASTRONOMY.NET" & "VA.NET" . ...

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• Astronomy Terms - To Help You Study The Universe - an Astronomy Net Article
• Big Bang: Nagging Doubts Remain - an Astronomy Net Bigbang Forum Message
• Magnification (Power) And Using Eyepieces - an Astronomy Net Article