Quasars and Distant Galaxies
How primeval matter cast with uniformity in all directions by an assumed violent explosion, called the Big Bang, gathered together into vast groups of starts and galaxies that evolved into the universe remains a mystery (Peterson 1990). There have been speculations about its origins, pieced together and offering new standards against which theories could be tested and measured. Some of these speculations involved cosmic strings, global textures and late-time phase transitions, notions too strange to merit acceptance. Cosmologists have to reconcile separate and contradictory observations in explaining the origins of galaxies and the structure of the universe, such as the receding of galaxies from one another and the astonishingly uniform glow of invisible radiation in the universe known as the cosmic microwave background, the left-over heat from the creation of the universe. These observations and the abundance of hydrogen, helium and lithium resulting from the initial explosion give credence to a symmetric, homogeneous, expanding universe and the generally accepted theory that a violent cosmic explosion marked the creation or start of the universe 10 to 20 billion years ago (Peterson).
This theory on the symmetric, homogeneous and uniform evolution is inconsistent with observable clumping of matter into galaxies, clusters of galaxies and "walls" and "bubbles" and the detection of very distant quasars, which indicate that some galaxies already existed when the universe was just less than a billion years old (Peterson 1990). The Big Bang assumption does not fit in, in that it does not allow enough time for the force of gravity to gather ordinary matter, such as neutrons, protons and electrons, into the patterns we see today. But the Big Bang theory has remained unchallenged for want of a viable and acceptable alternative. The cold-dark-matter of the universe theory postulates that a second after the Big Bang, the universe underwent a cosmic burp of rapid "inflation" when it expanded much faster than the normal Big Bang observed today. It has remained the easiest to study, the simplest and most capable of providing strong and concrete predictions. Scientists believe that this standard model will stay until overwhelming evidence builds up against it and they say that this has not been occurred.
I. Galaxies and Quasars
A quasar is an extremely distance, thus old, celestial object, whose power output is several thousand times that of our entire galaxy (Lexico Publishing 2005). A galaxy is any of the numerous large-scale aggregates of stars, gas and dust that constitute the universe. Since the time of Galileo, who first investigated the Milky Way by telescope, the galaxy is composed of stars and has its own "stars island," with the sun as just one of the 100,000 million stars comprising the Milky Way galaxy (Henbert 1984). Many years of detailed study reveal that there are thousands of millions of other galaxies beyond the limit of observable universe. These galaxies are classified into spirals, irregulars and ellipticals. Ours is a spiral galaxy. Most of its matter is not in the form of stars, gas and dust, but in some invisible material filling within and surrounding the galaxy.
Astronomers recognize two different kinds of active galaxy: the "starburst galaxies," which were discovered only in 1983 (Henbert 1984); and the strongest active galaxies with a central "powerhouse," that produces energy equivalent to that of a million millions suns and can also send the energy into space. Most astronomers agree that the only possible source for the concentrated power is the gravitational field around a black hole. As gas goes down into the black hole, up to 40% of its mass can be changed into energy. The theory is that it is possible that all spiral galaxies have a central black hole, but these galaxies are fuelled only 10% of the time.
Exciting news reports poured in that a large number of galaxies grew up quickly even when the universe was still young and that these galaxies were as large as the largest...
Of those 1,235, 68 are estimated to be Earth-size; 288 are super Earth-size; 662 are Neptune-size; 165 are the size of Jupiter, and 19 are larger than Jupiter (Science Daily). Of the 54 planet candidates that have been found in the habitable zone, five are near Earth-size. The other 49 left in the habitable zone range from super-Earth-size (up to twice the size of the Earth) -- to larger than
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