... December 31, 1995 . The X-ray Sources of M31 . Credit: ROSAT , MPE , NASA . Explanation: Just like our own Milky Way Galaxy , the nearest major galaxy M31 has many star systems spewing high energy radiation . ... The X-ray sources in M31 occur in globular clusters , the spiral arms , and near the galaxy's center. ... M31 has more X-ray sources near its center than our Galaxy, and the reason for this is currently unknown. ... About APOD | ... NASA Technical Rep.: ...
... 2000 September 21 . XZ Tauri System Ejects Gas Bubble . ... Explanation: Why is the binary star system XZ Tauri emitting a hot bubble of expanding gas? ... The XZ Tauri star system is known to reside in the Taurus star forming region located about 500 light-years away. ... The bubble has been expanding over the past thirty years and now extends to nearly fifteen times the binary separation. Tomorrow's picture: Star Cluster . ... About APOD | ...
... Here is a brief outline of the current theory of the events in the early history of the solar system: . A cloud of interstellar gas and/or dust (the "solar nebula") is disturbed and collapses under its own gravity. ... The gas cools off enough for the metal, rock and (far enough from the forming star) ice to condense out into tiny particles. (i.e. some of the gas turns back into dust). ... Once the larger of these particles get big enough to have a nontrivial gravity, their growth accelerates. ...
Prague, August 16, 2006 . ... Large classes (groups of types) : . ... Eruptive variable stars . ... Pulsating variable stars . ... Rotating variable stars . ... Cataclysmic (explosive and nova-like) variables . ... Close binary eclipsing systems . ... Optically variable close-binary sources of strong variable X- ray radiation . ... These classes are just a way to group types; in our opinion, they can be kept if slightly better described ( e.g ., remove close from item 5, simplify item 6) ...
ABSOLUTE PROPER MOTIONS OF 331 OPEN CLUSTERS . ... The proper motions of stars in the fields of 331 open clusters were taken from Four-Million Star Catalog (4M-catalog) of positions and proper motions (Volchkov et al. ... The absolute proper motions for 21 young open clusters have been derived by comparison of precise relative proper motions of individual stars and their corresponding absolute proper motions. ... Sign of proper motions in RA . ... 0.0001 arcsec/yr . ... rms error in RA proper motion . ...
. This is the faintest SNe, at mag. 18.3, yet detected by my system. Mike Schwartz , Director . Tenagra Observatories, Ltd. Cottage Grove, OR 97424 . Back to Bright Supernovae . David Bishop Last modified: Tue Feb 16 08:42:58 EST 1999
... Астрономические данные в Сети - где искать и как пользоваться? Сайты с астрономической библиографией . ... Солнечные сайты . ... Астероидные сайты . ... http://www.uic.rsu.ru/astro/ А наиболее полный список на сайты по теме " что почитать по астрономии " (по-русски) можно найти в соответствующем разделе рейтингового каталога АстроТоп-100 . ... Прекрасная система поиска позволит Вам найти обзорные статьи практически по любому разделу современной науки - от физики и астрономии до химии и биологии. ...
. Search the Web Usenet and Display the Results in Standard Form in Compact Form in Detailed Form as a Count only . Use only Advanced Query Syntax with AND , OR , NOT and NEAR . Simple Query Syntax will not work! . Results Ranking Criteria: documents containing these words will be listed first. If left blank, the matching documents will not be sorted. Start date: End date: e.g. 21/Mar/96 .
... The distance scales of the objects are matched both by comparing the first derivatives of the angular velocity determined separately from radial velocities and proper motions and by the statistical-parallax method. ... Good agreement between the inferred 0 and our calculations based on space velocities suggests that the Lindblad relation holds throughout the entire sample volume. ... Brandt and Blitz (1993) published the distances and radial velocities for a total of 206 H II-regions. ... Astron. ...