... Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer. 2011 March 26 . T Tauri and Hind's Variable Nebula . ... Explanation: The yellowish star near center in this remarkable telescopic skyview is T Tauri, prototype of the class of T Tauri variable stars. Nearby it is a dusty yellow cosmic cloud historically known as Hind's Variable Nebula (NGC 1555). ... About APOD | ...

Astronomy Picture of the Day . T Tauri and Hind s Variable Nebula . ... Credit Copyright: Don Goldman Explanation: The orange star centered in this remarkable telescopic skyview is T Tauri, protoytpe of the class of T Tauri variable stars. ... To further complicate the picture, infrared observations indicate that T Tauri itself is part of a multiple system and suggest that the associated Hind's Nebula may also contain a very young stellar object. ... Publications with keywords: T Tauri - nebula . ...

... Observing . ... Solar Observing . ... April 3 (SUN) - Solar Observing, Central Park , Manhattan . ... APRIL'S SKY . ... Lecture Series at the American Museum of Natural History The Amateur Astronomers Association is proud to present an astronomy lecture series from October through May each year for our members and the .. ... The€аAmateur Astronomers Association of New York€аwas organized in 1927 to promote the study of Astronomy, emphasizing its cultural and inspirational value. ...

... August 6, 1998 . Infrared Horsehead . ... Explanation: This famous cosmic dust cloud was imaged in infrared light by the European Space Agency's Infrared Space Observatory (ISO) satellite. The false-color picture shows the bright infrared emission from dust and molecular gas in part of the Orion star forming region surrounding the Horsehead Nebula . In visible light, the horsehead-shaped dust cloud looks dark against a background of bright glowing gas. ... About APOD > . ...

Making HST Pictures: Examples and Illustrations . ... These illustrations represent some of the steps and techniques used to produce “pretty pictures” from HST images. ... TIFFs (ftp) . ... Separate images are exposed through different color filters. ... An alternate way to make color images . ... Eight bit (one byte) images contain 256 different values that may be represented by 256 shades of gray or 256 arbitrary colors from a color map (or palette) of all possible colors. ...

... During the analysis of the surveys carried out on RATAN-600, it was found that almost one fifth of the detected sources shows significant radio flux variations. ... We used the data from "Cold" radio surveys carried out with RATAN-600 in 1980-1994 to search for radio sources with significant flux variability. ... On possibility of detection of variable sources using the data of Cold surveys carried out on RATAN-600. ... Detection of Variable Sources Using the Data of "Cold" Surveys. ...

In this gallery are many images of Low Surface Brightness Galaxies which have recently been discovered and analyzed. ... The central surface brightness of this galaxy is 24.28 . Malin 2 This galaxy is another huge disk galaxy with a scale length of 15 kpc and a redshift of 15000 km/a. The high surface brightness knot in one of its spiral arms actually has the same color, luminosity and H-alpha equivalent width as the entire Large Magellanic Cloud . ... Truly it is a Low Surface Brightness Galaxy. ...

Next: CONSTRICTOR Up: Plotting Previous: Adding plot variables Contents . A plot class is basically defined by the list of plot variables displayed in the x,y, and z axis selections of the plot selection widget. ... Furthermore, in the same widget procedure, the name of the new plot class needs to be added to each selection button if required. ... Finally, as far as the plot widgets are concerned, the new class needs to be added for each necessary index selection in ww_indexsel . ...

In autumn 1994, two groups of astronomers announced that they had discovered Cepheid variable stars in a distant cluster of galaxies. ... As the term suggests, variable stars change in brightness over time. ... Variable stars are an ideal way to get high-school students doing real science, with real data, from the real sky. ... a sky chart to find the stars . ... Students can use the nearby stars to estimate the magnitude of Delta. ... Locate the star Delta in Cepheus and estimate its brightness . ...

Next: An example of Up: Association of images Previous: Association of images . The two sets of selection criteria (``first choice'' and ``second choice'') have to be entered in a table containing four columns: . FUNCTION --character column (max 256 char) . This column defines the different selection criteria and shall contain mathematical expressions in which the variables may be the columns of the OST. ... RANGE_1 --character column (max 256 char) . ... WEIGHT --real column . ...

... We have compared visualized fields of GSC and USNO A1.0 catalog with unpublished photographic finding charts that were sent by L. Plaut to the compilers of the GCVS. ... 7-15 A9 --- GCVS GCVS or NSV name 17-25 F9.4 --- GSC GSC number 26 A1 --- NoteFlag *Nonstar (GSC) flag 28-29 I2 h RA2000GSC.h Hours RA (GSC), equinox 2000.0 31-32 I2 min RA2000GSC.m Minutes RA (GSC), equinox 2000.0 34-38 F5.2 s RA2000GSC.s Seconds RA (GSC), equinox 2000.0 40 A1 --- DE2000GSC.- ... Plaut, L., 1966, Bull. ...

... In collaboration with Drs Van Genderen (Leiden, Holland) and Sterken (Brussels, Belgium) papers XV and XVI in the series `Light Variations of Massive Stars' were published. These dealt with the brightness variations of several massive stars in the two nearest neighbour galaxies, namely six stars (R85, R99,