Andromeda Galaxy

Figure 2.12 Andromeda Galaxy. (A colour reproduction of this figure can be seen in the colour section). (Reproduced from photos by courtesy of NASA)...

The three broad classifications (elliptical, spiral and irregular) of star clusters that also cluster together to form the Local Group that contains the Milky Way and the Andromeda Galaxy, along with the Small and Large Magellanic Clouds... 

Figure 2.12 Andromeda Galaxy. (Reproduced from photos by courtesy of NASA)...

Although new stars (novas and supernovas) had been observed for many centuries, as can be seen from Chinese, Japanese and Korean chronicles, the modern, scientific age of supernovas only began on 31 August 1885, when Hartwig discovered a new star near the centre of the Andromeda galaxy. Eighteen months later the new star had disappeared. 

In 1919 Landmark estimated the distance to the Andromeda galaxy at some 700000 light-years. (Current estimates put it at 2 million light-years.) It was clear that Hartwig s star was a thousand times brighter than any known nova. It was the same Landmark who suggested a connection between the supernova observed by Chinese astronomers in 1054 (the year of the religious schism) and the Crab nebula. 

The probable black hole in the Andromeda Galaxy s central bulge has 30 million times the mass of the Sun. 

The planet Zoltan is located in a solar system in the Andromeda galaxy. On Zoltan, the standard unit for the amount of substance is the wog and the standard unit for mass is the wibble. The Zoltanians, like us, chose carbon-12 to define their standard unit for the amount of substance. By definition, one wog of C-12 atoms contains 2.50 x 1021 atoms. It has a mass of exactly 12 wibbles. 

The Andromeda galaxy. Promethium has been observed in the spectra of some stars in this galaxy. PHOTODISC/ROYALTY FREE. 

Virginia Trimble [96] reviews extensively the Supernova event seen 23. February 1987 in the Great Magellanic Cloud (at a distance about 170000 light-years, or about 10 times closer than the Andromeda galaxy). It has... 

The galaxies are separated from each other by enormous distances, the nearest large galaxy to our own (the Andromeda galaxy) being about 6.7 X 10 parsecs away. 

Local Group The group of galaxies of which our own Galaxy is a member, it consists of some 30-40 known members, the most massive of which are the Galaxy and the Andromeda galaxy. 

M ssl r Cataloguo A list of nebulae, galaxies, and star clusters, originally published (with 45 entries) in 1774. Such objects are referred to by their Messier numbers e.g. the Andromeda galaxy is M31. It is named after its originator, Charles Messier (1730-1817). 

As just mentioned, thirteen lanthanides had been discovered but, according to the new knowledge of the atom, one was missing. In 1914, Moseley confirmed that there must be an element with atomic number 61 between neodymium and samarium. Where was that element in nature Astronomical studies indicated that it is present on the surface of star in the Andromeda galaxy. But all attempts to find it on earth failed. The search had to take quite different paths than had been common in the whole history of lanthanide discovery. 

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