|M31 - NGC224 - Magn. 4.4 - Dist. 2.380.000 l.y.|
The Andromeda Galaxy is a giant spiral galaxy similar in form to our own galaxy but perhaps twice as massive. Deep observations show that the galaxy disk extends at least 4.5 degrees in length. The proximity of Andromeda has alloved detailed study which has given us much of our understanding of galactic rotation, stellar evolution and distance scales.
Andromeda Galaxy is visible to the naked eye and its feeble light was noted by persian astronomer Al Sufi about year 1000. It appears in a celestial chart in year 1609, before the discovery of the telescope. It was acknowledged as a galaxy in 1923.
Andromeda Galaxy has a well definite spiral structure whose diameter is about 180.000 l.y. (100.000 our galaxy). The dense core conteins almost only very old stars and the arms young giant blue stars instead.
M31 is the "leader" of the "local group" whose belongs our galaxy too.
M 31 - The Andromeda Galaxy
M 110 - NGC 205
Dist. 2.380.000 l.y.
Satellite of M 31
|NGC 884 - Magn. 4.4 - Dist. 7.200 l.y. - Half of Double Cluster|
NGC 869 - Magn. 4.3 - Dist. 7.200 l.y. - Half of Double Cluster
The California Nebula
Illuminated by Menkhib, Xi Persei
M15 - NGC7078
Magn. 6.4 - Dist. 30.600 l.y.
M15 is one of the most densely packed globular star clusters in our Milky Way Galaxy. This stunning Hubble Space Telescope image of M15 shows thousands of individual stars across the central 10 or so light-years of the cluster. Yet even the Hubble's sharp vision can't clearly separate the stars at this cluster's core. Globular star clusters harbor from a hundred thousand up to a million stars. Like most globulars, M15 is filled with ancient stars, about 12 billion years old. Its cool red giant stars appear yellowish in this color composite image. Unlike most globulars, M15 displays a planetary nebula, the briefly visible gaseous shroud of a dying star. Can you pick it out? Cataloged as Kuestner 648, M15's planetary nebula is the round pinkish cloud at the upper left.
Supergiant Spiral Galaxy
Dist. 48.9 millions l.y.
M 77 - NGC 1068|
Spiral Galaxy - Magn. 9.5
Dist. 81.5 mill. l.y.
This magnificient galaxy is one of the biggest galaxies in Messier's catalog, its bright part measuring about 120,000 light years, but its faint extensions going perhaps out to nearly 170,000 light years. M77 is about 80 million light years distant, and is receding from us at about 1100 km/sec; it was the second galaxy with a large measured redshift after the Sombrero galaxy, M104: the higher values would make M77 the most remote Messier object).
This galaxy is unique and peculiar because of several reasons. First of all, its spectrum shows peculiar features in the form of broad emission lines, indicating that giant gas clouds are rapidly moving out of this galaxy's core, at several 100 km/sec. Hubble classifies M77 as a Seyfert galaxy of type II (type I Seyfert galaxies exhibit an even larger expansion velocity of several 1000 km/sec); it is the nearest and brightest representative of this class of active galaxies.
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