Dark Matter :: physics science space

Missing Diagrams You, the computer you’re sitting at, the air you breathe, even the distant stars are all made up of protons electrons and neutrons. For a long time this ordinary matter, or what physicists like to call baryonic matter, was thought to be the main constitute of the universe. However, in the past twenty years evidence has been accumulating to the contrary, that in fact the universe is much stranger than ever thought of before and is almost entirely made up of something that we can’t see. For a long time astronomers weren’t concerned about the mass of objects that they couldn’t see. For example the earth is too small and dim to see from any great distance and all the planets in out solar system make up less than one percent of the total mass of the sun. However it soon became a concern when astronomers began to measure the mass of galactic clusters and it became apparent that there was a significant amount of matter unaccounted for. In the thirties, astronomers named Zwicky and Smith both examined closely two relatively nearby clusters, the Coma cluster and the Virgo cluster. They looked at the individual galaxies making up the clusters individually, and the velocities of the clusters. What they found was that the velocities of the galaxies were about a factor of ten to one hundred larger than they expected. In a cluster the main force is the gravitational pull of the galaxies on one another which gives rise to their velocities. By knowing the velocities of the galaxies the total mass of the cluster can be determined. If your web browser is Java-aware -- e.g., Netscape 2.0b or higher, try this experiment. It allows you to vary the mass inside a galaxy cluster, and watch the individual galaxies. Experiment I ( Courtesy of John's Homepage http://www.astro.queensu.ca/~dursi/dm-tutorial/dm1.html) Now like all observations there is a certain amount of error involved. In this case, watching the galaxies in a cluster takes years of observation and the velocities are hard to determine due to the expanse of the cluster. It’s not like the experiment were the dots are whizzing around. Also some of the galaxies measured may not be in the cluster but are just in the line of site of the telescope.

Harry Potter and the Sorcerer’s Stone Essay

Ever since the first printing of the first Harry Potter novel, the book series has been under attack from people arguing that the books are intended to initiate children into witchcraft and demonic practices or that they undermine traditional spiritual values. Yes, indeed, there are ghosts and Halloween, and the practice of magic. However, Harry Potter books are no more a threat to the traditional spiritual values of our children than The Wizard of Oz was before them. Harry Potter has not grown up in a â€Å"normal† family, even outside of the wizarding world. The Dursleys do not care for Harry and treat him poorly. They are clearly nominally Christians; in Chapter Two, Harry’s uncle threatens him with punishment, saying that Harry will â€Å"be in that cupboard from now until Christmas† if he is involved in any â€Å"funny business† (24). There is no evidence, however, that the Dursleys ever practice any particular faith. That lack of spiritual practice carries through the book, even in the wizarding world. .While no one falls to his or her knees in religious fervor, neither does anyone sacrifice a goat to Satan. Rowling has kept her books carefully neutral, but not because she wishes to undermine traditional spiritual values. Rather, it seems that Rowling wishes to appeal to the largest possible audience, without appealing to one spiritual belief over another. Rowling presents Halloween in such a manner that would appeal to the imagination of children, with bats, candles in pumpkins, and a feast; however, it is also merely a backdrop for the action that brings the Three Musketeers of Harry, Ron, and Hermione together (Rowling 172-179). Later in the book, the characters celebrate Christmas. Christmas, however, is no different from Halloween. The Christmas break serves only to give Harry a quiet moment to investigate the library and to investigate the Mirror of Erised (Rowling 204-209). Once again Rowling is carefully neutral, describing Christmas only in terms of what would appeal to children. While Rowling focuses primarily on food, gifts, and games, Ron’s brother George also takes the time to tell another brother that he will not be sitting with his fellow prefects, because â€Å"Christmas is a time for family† (203). Rather than glorifying the wizarding world, Rowling chooses to show that the wizarding world is no more appealing than the Muggle world. There are still bullies there: Draco Malfoy is just like Harry’s cousin, only he is thinner and can ride a broom. Friendship and loyalty and knowledge are all valued there; fellowship and fun are as much a part of the school as magic is. Harry Potter and the Sorcerer’s Stone is simply a fantasy story about a boy and his friends away at boarding school. The only real magic connected to this book is that it rekindled many children’s interest in reading. Who can truly argue with that result?

Apperences vs. Reality in Twelfth Night Essay - 851 Words

Appearances vs. Reality M.C Escher said, â€Å"Are you really sure that a floor cant also be a ceiling?† This quote is saying that what you see and what is actually there can be two different things. Appearances versus reality is a recurring theme in William Shakespeare’s play, Twelfth Night . Appearances hide an important reality and sometimes can get in the way of a character from developing or attaining his or her goal. The problems that happen involve disguises and deceit of one form or another and create tension amongst the characters. The reason Shakespeare has this recurring theme is because of the comedy that comes with it. It is funny for the reader to see the situational irony that occurs and is what makes the play.†¦show more content†¦Malvolio is mislead at one point of the play by Maria and Sir Toby. They write him a fake letter that is supposedly from Olivia saying how much she loves him. He only believes the letter because he loves her so much and will believe a nd do whatever it takes to be with her. This is his down fall with what appears to be a good situation for him, but is actually people playing tricks on him. He acts how he really feels in front of Olivia to only turn her off, and because of his own pride causes him to act foolish. Love itself is an appearance that beats reality when its taken to lightly and overcomes the reality so all you can see is the appearance of love. Count Orsino believes he is in love with Lady Olivia, however he is in love with the idea of being in love. He claims to love Olivia but really he is growing very fond of Viola/Cesario, this appears to be him loving these two women but is actually like stated previously him being in love with the idea of being in love. With Olivia mourning the death of her brother it is a viable excuse not to see men at the moment. However in