Galaxies

Turn Left at Orion: A Hundred Night Sky Objects to See in a Small Telescope —and How to Find Them   —Guy Consolmagno, Dan M. Davis, Karen Kotash Sepp, Anne Drogin, Mary Lynn Skirvin— (Seasonal Objects: Spring)       Galaxies are the basic units of the universe.       After the universe was created it seems to have fragmented into discrete lumps of matter, each with enough mass to make billions of stars.       A lump would condense into a galaxy, with a cloud of globular clusters swarming erratically around the galactic center, and a disk of stars orbiting the center.         Galaxies come in three general forms: elliptical galaxies, irregular galaxies, spiral galaxies.                Elliptical galaxies look like large, somewhat flattened globular clusters (a collection of tens of thousands of stars in a ball within the galaxy).         In spiral galaxies, stars are organized into two or more arms that twist around their galactic center. Spirals are the most beautiful of galaxies.           The Whirlpool Galaxy, and our own Milky Way are examples of spiral galaxies. The Whirlpool's companion may be an elliptical galaxy.         Galaxies are observed to be clumped together into clusters, which may be anywhere from a dozen to hundreds of galaxies, each tied by the gravity of others into a cloud moving together through space.                Andromeda and its companions, the Triangulum Galaxy, and the Milky Way and its companions (the Magellanic Clouds) are all part of the Local Group. The galaxies in Ursa Major and in Leo are examples of members of other groups.          All the clusters appear to be moving away from each other, implying that they are the fragments of the Big Bang that took place some twelve to fifteen thousand billion years ago.       The clusters themselves are associated into clusters of clusters called superclusters.       We don't know whether these superclusters are independent entities, like raisins in a pudding, or connected together like the stuff in a sponge around “bubbles” of empty space.

Glimpsing the Mind of God

The Goldilocks Enigma: Why Is the Universe Just Right for Life? - Paul Davies – (Chapter 1: The Big Questions)         The great questions of existence: Why are we here? How did the universe begin? How will it end? How is the world put together? Why is it the way it is?       Observations made using satellites, the Hubble Space Telescope, and sophisticated ground-based instruments have combined to transform our view of the universe and the place of human beings within it.       One of the most significant facts — arguably the most significant fact — about the universe is that we are part of it.       Carbon is the key life-giving element, but oxygen, hydrogen, nitrogen, sulfur, and phosphorus are crucial too. Liquid water is another essential ingredient.                If almost any of the basic features of the universe, from the properties of atoms to the distribution of the galaxies, were different, life would very probably be impossible.         Like the porridge in the tale of Goldilocks and the three bears, the universe seems to be "just right" for life, in many intriguing ways.         ...the everyday world observed through our senses represents only the surface manifestation of a deeper hidden reality, where the answers to the great questions of existence should be sought.           ...about 350 years ago, the greatest magician who ever lived finally stumbled on the key to the universe — a cosmic code that would open the floodgates of knowledge. This was Isaac Newton —               The particular brand of "magic" employed by the early scientists involved hitherto unfamiliar and specialized procedures, such as manipulating mathematical symbols on pieces of paper and coaxing matter to behave in strange ways.          Newton, Galileo, and other early scientists treated their investigations as a religious quest. They thought that by exposing the patterns woven into the processes of nature they truly were glimpsing the mind of God.         ...beneath the surface hubbub of natural phenomena lies an abstract order, an order that can't be seen or heard or felt, but deduced.         Somehow the universe has engineered, not just its own awareness, but also its own comprehension. Mindless, blundering atoms have conspired to make not just life, not just mind, but understanding.