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Gold Barz
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To form, is it one of the oldest?
The currently best estimate of the age of the Universe, as deduced, e.g., from measurements of the Cosmic Microwave Background, is 13,700 million years. The new observations thus indicate that the first generation of stars in the Milky Way galaxy formed soon after the end of the ~200 million-year long "Dark Ages" that succeeded the Big Bang.
Most of the galaxies we know are elliptical in shape. The largest of these elliptical galaxies may contain as many as 10 trillion stars (10 trillion solar masses) and may be as large as 100,000 parsecs in diameter. (This is comparable to the size of our galaxy - including the entire disk of our galaxy - but with about 100 times more stars. No wonder they are so bright!) Such huge galaxies are called Giant Ellipticals (an example is shown above). They are rare but spectacular. Most of the ellipticals are Dwarf Ellipticals, which have approximately a few million solar masses and diameters of about 2000 parsecs. They are low surface brightness objects. Dwarf Ellipticals generally are found in galaxy clusters or near large galaxies. from the Department of Astronomy, University of Maryland
Astronuc said:Spirals are not the most common type of galaxy.
This is a difficult question to answer definitively. While evidence suggests that our galaxy, the Milky Way, is relatively young compared to other galaxies in the universe, it is impossible to determine if it is one of the first. The concept of "first" in this context is subjective and depends on the definition of "galaxy". Some scientists argue that smaller, less organized structures existed before the Milky Way, while others argue that the Milky Way was the first fully formed galaxy.
To determine the age of our galaxy, scientists use a variety of methods. One common method is to study the chemical composition of stars in our galaxy. By analyzing the amount of heavy elements present in these stars, scientists can estimate the age of the stars and therefore the age of the galaxy. Additionally, scientists also use computer simulations and observations of other galaxies to estimate the age of the Milky Way.
There are several pieces of evidence that suggest our galaxy is relatively young compared to other galaxies in the universe. First, the Milky Way is still actively forming new stars, which is a sign of a young galaxy. Additionally, the Milky Way has a relatively low number of globular clusters, which are clusters of stars that are typically found in older galaxies. Furthermore, studies of the chemical composition of stars in our galaxy also suggest a relatively young age.
It is possible that there are older galaxies in the universe that we have not yet discovered. This is due to the vastness of the universe and the limitations of our technology and observation methods. However, based on current evidence, it is unlikely that there are significantly older galaxies than the Milky Way.
The age of our galaxy is a significant factor in the search for extraterrestrial life. If our galaxy is relatively young, it means that there may be other younger galaxies in the universe that could potentially harbor life. This increases the chances of finding extraterrestrial life in the universe. Additionally, the age of our galaxy also affects the development of life on Earth. If our galaxy is one of the first, it means that life on Earth may have had more time to evolve compared to life on planets in younger galaxies.