... 22.02.2011 . ... Credit Copyright: morn1415 (YouTube) Explanation: How big is our Sun compared to other stars? In a dramatic and popular video featured on YouTube , the relative sizes of planets and stars are shown from smallest to largest. ... Note that the true sizes of most stars outside of the Sun and Betelgeuse are not known by direct observation, but rather inferred by measurements of their perceived brightness , temperature , and distance. ... Publications with keywords: star - planet . ...

... About ATNF overview . ... Australia Telescope Steering Committee . ... Murchison Radio-astronomy Observatory . ... Parkes radio telescope . ... Australia Telescope 20GHz Survey . ... Bright prospects: Comparing the H Survey with large-scale radio continuum emission . ... Prospects for comparisons between the AAO/UKST H \ survey and large-scale radio continuum emission are considered, with particular reference to the recently completed Parkes 2.4-GHz survey of the southern Galactic Plane. ...

... 2011 February 22 . Star Size Comparisons . ... Explanation: How big is our Sun compared to other stars? In a dramatic and popular video featured on YouTube , the relative sizes of planets and stars are shown from smallest to largest. ... Note that the true sizes of most stars outside of the Sun and Betelgeuse are not known by direct observation, but rather inferred by measurements of their perceived brightness , temperature , and distance. ... About APOD | ...

... The sample of the Local Volume galaxies (distance smaller than 10 Mpc) gives a unique opportunity to study the properties of galaxies including the weakest objects: the absolute magnitude M B -10 and the virial mass M vir 10 9 M x263C;. ... Luminosity function of the Local Volume galaxies. ... The luminosity functions for galaxies are presented: red dashed line - from the 2dFGRS survey (Norberg et al. 2002); blue dash-dotted line - from the SDSS survey (Blanton et al. ...

Star formation is often best manifested by bright H II regions.These are regions of hydrogen which have been ionized by ultraviolet photons which are emitted from massive stars (typically stars more than 20 times the mass of the Sun). ... A narrowband filter image centered on this wavelength will then readily reveal these H II regions and hence the current sites of star formation in a galaxy, The luminous blobs that can be seen here are all H II regions . ... NGC 3558 Visual . NGC 3558 Infrared . ...

... 1.2 Completed Four Sets of STIS/CCD 8549 (POMS Test Proposal: Non-Scripted Parallel Proposal Continuation I) The Space Telescope Imaging Spectrograph (CCD) was used to make low galactic latitude, non-scripted parallel observations as part of a POMS test proposal. ... 1.7 Completed STIS/CCD 8202 (Bright Quasar Close Lensing Search) The Space Telescope Imaging Spectrograph (CCD) was used to make observations of HCLQ1431+3 as part of a second generation survey to search for bright lensing quasars. ...

Constraining the Cosmic Mass Density from the SBF Survey Peculiar Velocities J.P. Blakeslee et al. University of Durham, U.K. The recently completed I-band Surface Brightness Fluctuations (SBF) Survey of Galaxy Distances includes high-quality distance measurements to nearly 300 early-type galaxies within 4000 km/s. We compare the peculiar velocities observed in this survey with those predicted from the galaxy density eld found in ux-limited redshift surveys. ...

... Since the reddening found for the stars in Table 13 was small, no reddening correction was attempted. ... These diamonds indicate the positions of very low mass, 3 Myr old, objects from the work of Burrows et al. ... This optical V versus R - I scheme is a very powerful method of detecting very low mass (VLM) objects. ... Because of this, young brown dwarfs are intrinsically no more difficult to observe in the optical than low mass stars at the age of Orionis. ...

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 | ...

The LCDM paradigm: successes and challenges on scales of galaxies Anatoly Klypin (NMSU) LCDM · · · · DM profiles, concentrations, .. Clustering of galaxies: P(k) and correlation functions Satellites: abundance, number-density profiles Galaxies and Dark Matter: abundances Dwarfs. ... Springel et al 2008. ... Klypin et al 2010. ... Observations - LCDM: just enough Magellanic Clouds Observations LCDM Vmax > 50 km/s Busha et al 2010 Dark matter profiles: standard LCDM Aquarius simulation. ...

... The sky distribution of the BCGs from the HSS sample is shown in Fig. 6 together with BCGs from the SBS and Case surveys (Izotov et al. [ 1993b ]; Pustilnik et al. ... First, we compare the apparent magnitude distributions of the three samples. ... The similar behaviour of the faint end of the apparent magnitude distributions infers that the Northern BCG sample may have a similar completeness down to this limiting magnitude. ...

EPIC CTI XMM-Newton Science Operations Centre D Lumb EPIC Cal/Ops Feb2001. ESA HQ 1 EPIC CTI XMM-Newton Science Operations Centre D Lumb EPIC Cal/Ops Feb2001. ESA HQ 2 EPIC CTI contd · SAS correction assumes charge loss ~ c + b*E · Note the change with time also fn(E) · Complete the analysis for other CCDs and other observations XMM-Newton Science Operations Centre D Lumb EPIC Cal/Ops Feb2001. ... ESA HQ 6 MOS Vignetting (Rev65) XMM-Newton Science Operations Centre D Lumb EPIC Cal/Ops Feb2001. ...

... Gravitational wave search provides insights into galaxy evolution and mergers . ... galaxies . ... Globular cluster NGC 2808, elliptical galaxy NGC 2986, and the Sextans Dwarf . ... Open cluster NGC 2818, spiral galaxy NGC 2964, and spiral galaxy NGC 2976 . ... What are typical star-to-star distances in globular clusters compared to stellar distances in our region of the galaxy? ... RELATED TOPICS: GLOBULAR CLUSTERS . ... Get instant access to subscriber content on Astronomy.com! ...

... The distribution of redshifts among the DXRBS FSRQs identified so far (Figure 3) is quite similar to that of the 1 Jy and S4 samples. ... A more thorough comparison will have to await completion of our survey and the convolution of the redshift distribution with the WGACAT sky coverage. As has already been mentioned by Hook et al. (1996), selecting flat-spectrum sources is an efficient way of finding high-redshift, radio-loud quasars. ...

The horn on the lbw receiver was switched from a kildal horn to one designed by german cortes in feb2003. On 11jul03 we did a test comparing tsys vs frequency for both horns. ... The measurements started around 9:30 AST and finished at about 11:20 am. ... Cortes horn tracking ra/dec: 6:40:00/14:12:30 start at 11:10 AST To select the blank sky I used NVSS and looked at 1 degree around the positions to see that there were no strong sources nearby. ... POLA. tsys vs frequency. ...

Check out the new images (Jan 18-25) and (Jan 26-Feb 05) of the comet by Rob McNaught. ... Every few years a comet becomes bright enough to be easily seen with the naked eye but only every decade or so are these comparable with comets like Halley. ... Before Jan 13, the comet is not visible in the Australian sky after sunset. ... SOHO images . ... On Jan 12 at approximately 09:00 UT (8pm NSW time), comet C/2006 P1 McNaught appears at the 11 o'clock position in the images. ... STEREO images . ...

... This file table3.dat 108 715 YSO candidates in the ISOGAL survey -------------------------------------------------------------------------------- Byte-by-byte Description of file: table3 ... Format Units Label Explanations -------------------------------------------------------------------------------- 1- 24 A24 --- Name ISOGAL source name (based on J2000 coordinates) 26- 33 F8.4 deg Glon Galactic longitude 36- 42 F7.4 deg Glat Galactic latitude 44- 48 ...

November 2006 Astronotes 1 Candles in the Dark Image Credit: Wikipedia.org By Colin Johnston, Science Communicator Since the mid-ninteenth century astronomers have used the principle of parallax to measure the distance to other stars. ... How then can we tell, for example, that M31, the galaxy in Andromeda, is 2.2 million light years away? It would be straight-forward to tell how far away a star was if it was exactly the same brightness as our own Sun. ...

... Space Research Institute . Main . ... Main research and development work completed in 2012 and ready for implementation . ... Main research and development work completed in 2011 and ready for implementation . Main research and development work completed in 2010 and ready for implementation . Main research and development work completed in 2009 and ready for implementation . Main research and development work completed in 2008 and ready for implementation ...

... Up: VO Resources . ... Monkewitz, S. & Good, J. 2003, in ASP Conf. ... We describe the architecture of a general cross-comparison engine capable of spatially matching sources in one astronomical source catalog with those in another. ... Support is provided for common catalog formats and data sources (e.g. local disk, database servers), and the addition of support for custom data formats and sources is simplified by the modular architecture employed. ... Data Access: . ... Source List Processing: . ...