| Emily Duran12/3/2012 |
Black Holes:
Introduction
Eight hundred million years ago was when the first earliest black hole discovered. A black hole (2008) is a spot in space where gravity pulls a lot that not even light cannot escape; it is formed when a star is dying. The black holes’ gravity is very strong due to the matter being compressed to a tiny space (Heather, 2008, para. 1). The black holes (2011) began creating after the Big Bang (big bang is a theory that Edwin Hubble stated that the Universe was expanding at vast speed); it is also part of the reason for galaxy formation. Additionally, the baby black holes led scientists to believe that it is the evolution of the infant universe (Krishnan, 2011, para. 1). Black holes are typically huge as the sun or larger and small as an atom. But even the tiniest black holes have a mass of a large mountain (Heather, 2008, para. 3). According to Heather (2008), stellar mass is a type of black hole which has twenty more times more mass than the sun. There are vast of stellar black holes in Earth’s galaxy. The Earth’s galaxy is called the Milky Way (Heather, 2008, para.4). The Milky Way is the brightest object in the gamma-ray sky (Naeye, 2012, para. 1). Moreover (2008), the largest black holes are named super massive; super massive have masses that are more than one million suns combine. Every large galaxy has a super massive black hole at its center; and the Milky Way galaxy center is called Sagittarius A.  Sagittarius A can fit inside a very large ball that holds a few million Earths and its mass is almost equal to four million suns (Heather, 2008, para. 5).
Formation of black holes
Scientists believe the formation of a black hole is due to when the center of a large star collapses or falls in upon itself (Heather, 2008, para. 7). The formation process only occurs to stellar black holes, which the procedure causes a supernova. In space, a star explodes which spreads the star throughout space, this is called a supernova. According to Heather, supernova is created at the same time as the galaxy they are in (Heather, 2008, para. 8).
Identifying a black hole
Black holes cannot be seen because light enters but it cannot escape, therefore, black holes are invisible. There are special tools that assist in finding black holes; the special tools demonstrate how stars that seem close to black holes act differently than other stars (Heather, 2008, para. 2). NASA studies the black holes using satellites and telescopes that are traveling in space; these machines facilitate scientists answer questions about the universe (Heather, 2008, para. 14). With the telescopes and satellites, scientists can see how strong the gravity affects the stars and gas surrounding the black holes. Scientists study the black holes to find out if they are flying around or orbiting (Heather, 2008, para. 9). Heather (2008) stated, “When a black hole and a star are close together, high-energy light is made” (Heather, 2008, para. 10). The light can only be seen by a specialized telescope.
How to view a black hole
Semeniuk states (2009), the largest black holes reside in the center of the galaxy, which is more than 30,000 light years away from the Milky Way (Semeniuk, 2009, para. 2). Unfortunately, because of its great distance it is hard to view; it is thirty-six million times smaller than the Moon (Semeniuk, 2009, para. 3). The device used to see the black holes in the Milky Way and even larger ones at that, it is by using satellites. The VLBI (2009) (vlbi stands for very long baseline interferometry) involves two or more radio dishes that are spaced as far apart as possible, as stated by Semeniuk. According to Semeniuk, the dishes observe certain radio sources in space which in turn their signals, when combined, gives of a sharp image (Semeniuk, 2009, para. 4). The gases electrifying ions provides radio waves, if seen up close a dark sphere where the center is of the swirl of gas; that matter would enter but not exit. As stated by Semeniuk (2009), the dark sphere is the event horizon, the point of no return. Semeniuk articulate (2009) “seeing the black hole means seeing the event horizon silhouetted against the glowing gas” (Semeniuk, 2009, para. 7).
Earliest black holes
The images taken from the Hubble Ultra-Deep Field and the Chandra Deep-Field South Survey were combined to show the earliest black hole. Ezequiel Treister (2011), an astronomer from the Institute of Astronomy in Hawaii, develops a team of astronomers to mount x-ray images for 250 separate galaxies to yield a hyper-deep image of an average galaxy. Treister team concluded that many or most of the ancient galaxies do contain black holes (Krishnan, 2011, para. 3). For awhile (2011), astronomers always wonder what came first: black holes or the galaxies around them. A popular model implies that an early star must have exploded as a supernova to create a ravenous seed black hole that gravitationally amassed enough gas to support an entire galaxy of stars around it. The gas and dust burying infant black holes helps the cosmologists advance their knowledge (Krishnan, 2011, para. 5). In recent observations, Chandra shed some light on a process call reionization that occurred in the infant universe, according to Krishanan (2011, para. 8). In reference to Krishanan (2011), after the Bing Bang, the universe was heated with background radiation and filled with hot, ionized plasma; similar to a microwave. When it began to cool and expand, neutral hydrogen atoms began to form within the plasma, creating a dense cosmic fog which was thick to light. During the dark times of the universe, it was believed that the universe have ended pockets of accumulating dark matter that caused gas to compress around it and have the first fusion reaction which produced the stars (Krishanan, 2011, para. 8). Moreover (2011), “The heat and light from these reactions catalyzed a process of re-ionization that cleared the fog and made the universe transparent to light again” (Krishanan, 2011, para. 8). In summary, the earliest black hole was capture by using two different satellites, the Hubble Ultra-Deep Field and the Chandra Deep- Field South, which picked up frequencies in the sky.
Is it possible a black hole can destroy the Earth?
According to Heather (2008), it is not possible for the Earth to be destroyed by a black hole. Believe it nor not, black holes do not prowl around eating stars, planets, or moons. There is no black hole near the solar system that the Earth would fall in (Heather, 2008, para. 11). Even if the black hole replaces the sun, the Earth will still not fall in. The black hole, having the same mass as the sun, would have the same gravity as the sun. As stated by Heather (2008), the sun will never turn into a black hole, since it is not a big enough star to make a black hole (Heather, 2008, para. 13).
Truth and lies about black holes
Black holes are known as vacuums because they inhale everything that not even light can escape and it cannot be seen. Apparently, not all is true about the black hole. Not all the substance of the material is inhaled by the black hole; part of the material is absorbed and the rest surround the black hole forever (Chandra, 2012, para. 2). The Earth will not get swallowed in the black hole if it replaced the sun, this is true. According to Chandra (2012), as long as the black hole has the same distance and mass as the Sun, the Earth will not budge (Chandra, 2012, para. 3). Fact, the black hole has matter spinning around it, similar to a disk; this formation is called accretion disk (Chandra, 2012, para. 4). As stated by Chandra (2012), “within the accretion disks around black holes, the atoms and molecules jostle each other with increasing ferocity as they rub together in a spiraling mosh-pit death dance as they are pulled towards the hole” (para.5). In other words, the substances are fighting for their lives while being pulled down the black hole. The material surrounding the black hole does not fall because they are not close enough to the hole; the only way it can fall in to the black is through outflows. Outflows are the matter circling the black hole; black hole outflows can form impressive winds and jets of power and multiplicity (Chandra, 2012, para. 7). It seems that, black holes do not only inhale but it exhales as well. The black hole is similar to a drain; when a person is washing her/his hair all the water is falling into the hole and the hair stays behind until something intervenes for the hair to fall in as well. Outflows from super massive black holes shut off the growth of galaxies or even stop the inflow of gas towards the center of galaxy clusters, as stated from Chandra (2012, para. 9). The lie about black hole is that they are just enormous vacuums; the truth is they only take in part of the material. The lie that black holes are the destroyer; the truth is they are indeed the creator of galaxies.
Conclusion
The Big Bang played a great part in the first seen black hole. Thanks to Hubble Ultra-Deep Field and the Chandra Deep-Field South observations, astronomers were able to detect a black hole in the center of galaxies. Black holes can only be seen by satellites that are far apart from each other reading the energy by radio frequencies. Black holes are not just destroyers of material but they are also creators of material. And yes, the Earth is safe from black holes.
Bibliography
I
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II
Heather R. Smith/NASA Educational Technology Services. (2008, September 30). What is a
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III
Krishnan, S. (2011, June 17). The Earliest Black Hole. Retrieved October 24, 2012, from Sky
and telescope: http://www.skyandtelescope.com/community/skyblog/newsblog/124073594.html
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V
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