Stars color

Fig. 2. Variation in [a/Fe] in Galactic stars (color coded by stellar population as in Fig. 1) and dSph stars (black squares).

Figure 3. Coalescence of a corotating neutron star binary system (1.4 Mgeach star). Color-coded is the column density, the axes are in kilometers. The simulations are described in detail in Rosswog et al. 2002.

At the boundary between two colors, colors produced will generally be less attractive than either star color. 

SYMBOLl V = dot COLOR = black SYMBOL2 V = Star COLOR = black SYMBOL3 V = dot COLOR = black ... 

Fig. 1. The coloi-coloi diagrams for TTauri stars in lhiinis>Auriga. Main-sequence star colors are shown by the solid line, the dashed lines represent the reddening lines.

Scandium is apparently much more abundant (the 23rd most) in the sun and certain stars than on earth (the 50th most abundant). It is widely distributed on earth, occurring in very minute quantities in over 800 mineral species. The blue color of beryl (aquamarine variety) is said to be due to scandium. It occurs as a principal component in the rare mineral thortveihte, found in Scandinavia and Malagasy. It is also found in the residues remaining after the extrachon of tungsten from Zinnwald wolframite, and in wiikite and bazzite. 

Wire sparklers are wires coated with pyrotechnic composition which are hand-held and produce a gende spray of gold sparks from iron filings. Fountains are cardboard tubes filled with chemical mixtures that produce a spray of color and sparks extending 2—5 m into the air. Roman candles are cylindrical tubes which repeatedly fire colored stars distances of 5—20 m into the air. These items typically contain 5—12 stars. 

Flares, Signaling Devices, and other Pyrotechnics. A large number of formulations contg K perchlorate have been reported. Some devices which use these are red RR signal flares (Refs 2 22, p 275) parachute flares (Ref 6) stars for use in signaling pistols (Very pistols) (Refs 5. 22, p 275) variously colored flares (Refs 19, pp 197-8 22, p 275) stars and other components of display fireworks (Refs 16 32) ... 

The color of a hydrogen-burning star depends on its mass the higher the mass, the higher the temperature of the star and the more blue it appears. 

In that one percent, iron, sodium, calcium, rare elements like scandium, and even elements not found on earth, like technetium, have been discovered. These elements and many others can be identified in the atmospheres of stars by spectroscopy, a method of analyzing the light emitted by our sun and other stars. Each element, whether on the earth or outside of it, always produces a certain, characteristic pattern of colored lines of light when... 

Abstract. We use intermediate resolution (II, 19 300) spectroscopic observations in the spectral region including the Li 6708 A line to study 341 stars in the star forming region (SFR) NGC 6530. Based on the optical color-magnitude diagrams (CMD), they are G, K and early M type pre-main sequence (PMS) cluster candidates. 72% of them are probable cluster members since are X-ray sources detected in a Chandra-ACIS observation ([2]). We use our spectroscopic measurements to confirm cluster membership by means of radial velocities and to investigate the Li abundance of cluster members. 

Fig. 1. Various color-magnitude diagrams for NGC 1851 obtained with uvby filters at the Danish 1.54m telescope on La Silla. Seven stars in our sample have previous low-resolution spectroscopy from [2] which classified them into CN strong (open squares) and CN normal (plusses) groups. Note how the CN strong stars stand out clearly from the cluster sequences when using filter combinations involving the u and v filters. We see from the lower righthand panel that the RGB stars in this cluster also show a large scatter in the mi index at a fixed luminosity - this is the only cluster in our sample of 20 which show mi scatter. This points to very large C variations (larger than for other clusters). Could this be related to the bimodality of the cluster horizontal branch ...

We have first explored the Li line region (670.7nm) for faint stars (bottom of the RGB, the RGB Bump area and the HB, see Fig.l). Data reduction has been done with the GIRAFFE DRS on 123 spectra (signal to noise ratio around 70). The log g have been estimated with a fit of the mean RGB and HB sequences of 47 TUC to a theoretical isochrone (Bertelli et al. 1994), and Teff have been estimated from the (V-I) color-temperature relations (Houdashelt et al., 2000). With [Fe/H]= - 0.65 for 47 TUC, synthetic spectra have been computed from MARCS models (log g= 3.0 TejJ= 4800 K to 5100 K). Li abundances (A Li>0 dex, Li dots in Fig.l) have been derived for 41 stars (with uncertainties of about 0.2dex). 

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