... 2001 June 14 . Around The Arches Cluster . Credit: X-ray; NASA / CXC / Northwestern / F. Zadeh et al., IR; NASA/ HST /NICMOS, . ... Explanation: The most compact cluster of stars known in our galaxy, the Arches cluster , boasts 100 or so massive, young stars contained within a diameter of one light-year. ... Astronomers consider the tightly packed and relatively nearby Arches cluster, an analog of the furious star forming regions in galaxies millions of light-years away. ... About APOD | ...

... Star Atlas . ... solar system . ... stars . ... Observe the Solar System . ... What factors determine if a massive star (say, 100 solar masses) forms instead of a Sun-like star? ... Stars of all masses form from dense clumps within exceptionally cold molecular clouds. ... Massive stars tend to form at the centers of high-mass reservoirs of gas. Get instant access to subscriber content on Astronomy.com! ... A gamma-ray burst hints that LIGO's double black holes started as one massive star . ...

We hosted an interdisciplinary two-day workshop on Solar Astronomy and Statistical inference at the CfA on Feb 16-17, 2012. ... Format: On the first day of the workshop, we had two tutorial sessions, one describing solar data for statisticians and the other describing statistics methods for astronomers. ... Presentation slides and video recordings are available via SIP (see links in session schedule details below). ... Video [.mov] (@SIP) . ... Massive solar data streams -- Alisdair Davey (CfA) . ...

... October 18, 1999 . NGC 3603: An Active Star Cluster . ... Explanation: NGC 3603 is home to a massive star cluster, thick dust pillars, and a star about to explode . The central open cluster contains about 2000 bright stars, each of which is much brighter and more massive than our Sun . ... These stars are less massive than our Sun, demonstrating that great numbers of low-mass stars also form in active starburst regions . ... About APOD > . ...

... Are HVCs a common feature of star forming galaxies? ... Consider the typical properties of the smallest HVCs (compact HVCs) found in HIPASS: . Distance . HI Mass . ... At 5 kpc . meager objects ~116 solar masses . ... 1.15 x 10 4 solar masses . ... Putman et al. (2003) found none to 10 7 solar masses. 2% of Sculptor to 3 x 10 6 solar masses by de Blok et al. (2001) found none. ... High velocity gas around other galaxies can be identified from maps and dynamics: . ... 2003) . ...

... Development of Ideas of Structure and Evolution of Stars. Integral Features of Stars, Which Determine Their Structure, Direction and Rate of Evolutuion. ... Connection between Potential and Thermal Energy of Star. ... Structure of a Main Sequence Star. Features of Massive Stars Evolution on the Main Sequence. Internal Structure of the Sun. ... White Dwarfs, Their Features. ... Evolution from the Main Sequence of Massive Stars. ... Evolution of Small Mass Stars till White Dwarfs Sequence. ...

... Table data are arranged in columns and rows, and stored in MIDAS files with the extension .tbl . ... An item in a table is accessed by giving its column and row in addition to the table name. The row number can either be given as an absolute value (i.e. the sequence number) or indicated by the value in a previously defined reference column. ... A table can be always expanded in the sense that its number of columns and rows is automatically increased when the allocated space is exceeded. ...

... These Frontier Fields will combine the power of HST with the natural gravitational telescopes of high-magnification clusters of galaxies. ... We are soliciting gravitational lensing maps for the last four Hubble Frontier Fields clusters (MACSJ0717.5+3745, MACSJ1149.5+2223, AbellS1063, and Abell 370) based upon the exceptionally deep HST FF imaging and other new ancillary data. ... For the full set of proposal instructions and requirements, see the FY16 Frontier Fields Lensing Map Call for Proposals....

Databases (NSDC) of the Natural Planetary Satellites. ... NSDC: Database of astrometric observations of Natural Planetary Satellites . ... They are thoroughly looking for observations in different sources, creating their owndatabases which are then mostly inaccessible to other researchers. ... In the file "content" with explications, the reference is given to the data source as well as the bibliographic reference. ... Data sources. ... Why a specific bibliographic database for Natural satellites? ...

Next: Amorphous magnesium silicate Up: Examples of data contained Previous: Examples of data contained . ... We have used the infrared optical constants of forsterite contained in the database for calculating the absorption cross sections of spherical and non-spherical particles in the Rayleigh limit (see Fig. The spectra are obtained by averaging the cross sections calculated for the three different crystallographic directions. ...

The Shark Nebula . ... Credit Copyright: Maurice Toet Explanation: There is no sea on Earth large enough to contain the Shark nebula. This predator apparition poses us no danger, though, as it is composed only of interstellar gas and dust . ... After being expelled with gas and gravitationally recondensing, massive stars may carve intricate structures into their birth cloud using their high energy light and fast stellar wind s as sculpting tools. ... NASA Official: Jay Norris. ...

Next: Imaging Polarimetry with NICMOS Up: NICMOS Data Calibration and Previous: The Photometric Performance of . ... NICMOSlook and Calnic C . ... Extracting spectra from a large number of NICMOS grism images requires a convenient interactive tool which allows a user to manipulate direct/grism image pairs. ... NICMOSlook and Calnic-C are two programs that were designed to take advantage of the fact that the NICMOS grism mode typically consists of taking both a direct and a grism image. ...

... In this paper, a project aiming to allow access to data archives by means of a query-by-example mechanism is described. The basic user query would simply be the submission of an input image, either 1-D or 2-D; the system should allow retrieval of archived images similar to an input one on the basis of some ``resemblance parameter". ... A system called QUBE is currently being designed to support the QUery-By-Example paradigm in accessing astronomical data archives. ... the QUBE User Interface. ...

... Takuya Akahori "Faraday Rotation Measure due to the Intergalactic Magnetic Field" . Shae Brown "Cross-correlation of ATLAS and Spitzer-SWIRE Surveys: Probing intergalactic magnetic fields" . Roger Clay "Using low energy cosmic rays to investigate local galactic magnetic fields" . Roland Crocker "A new lower limit on the magnetic field around the Galactic Centre" . ... JinLin Han "Rotation measures of pulsars and radio sources for Galactic magnetic fields" . ...

Next: Ejectors in Massive Binary Previous: Artificial Galaxy: Full Matrix . The first version of the Scenario Machine was aimed especially at the simulation of massive binary star evolution. ... First, there is a large class of intermediate mass binaries (say, consisting initially of 8 + 5 solar masses) that can also produce NS and thus lead to the formation of a bright X-ray source. ... Next: Ejectors in Massive Binary Previous: Artificial Galaxy: Full Matrix Mike E. Prokhorov . ...

Since the light from galaxies represents the integrated contribution of its consitutient stars, then we can learn about stellar populations in galaxies by modelling their light by summing up individual stellar spectra for different kinds of stars. ... The data cover the wavelength range 3500 - 9000 angstroms. ... Retrieve Digital Stellar Spectra Click on the appropriate spectral type. ... Note that the designation V means main sequence, IV means subgiants, III means giants, I means supergiant. ...

Orbital intersection . ... Structure of Taurid stream . ... Meteoroid swarm and Taurid fireballs . ... The following four diagrams schematically show four different Taurid orbits and the orbits of Earth and Jupiter. ... The Taurid stream contains particles (small, solid grains) at different stages of their precession cycles. ... The study of when a meteor stream can produce a meteor shower is the study of when precession brings orbits to intersection with Earth, or e.g. with Mars . ...

... Co-ordinate systems description . Directories structure . The file names' construction . The file set description . ... The orbital information for each month is presented in the separate directory. The INTERBALL orbital data are located on the STDA server, for each month in the separate subdirectory, which name consists from the year (YYYY) and month (MM) numbers. The Parent Directory of the Tail Probe orbital data is http://www.iki.rssi.ru/da/interball/tail/orbit/ . ...

Class 1 Introduction, Background History of Modern Astronomy The Night Sky, Eclipses and the Seasons Kepler's Laws Newtonian Gravity General Relativity Matter and Light Telescopes Class 2 Solar System Characteristics Formation Exosolar Planets Class 3 Stars The S un Stellar Evolution of Low and High Mass Stars Deaths of Stars Exotic Stars Class 4 Galaxies Galaxy Classification Formation of Galaxies Galactic ... Low mass stars live and die differently than high mass stars. ...

... 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. ...