To Wonder At

Though I follow closely what is reported about the wonders of what lies beyond this planet, the immensity of the universe continues to amaze me. In the past week I had to express a mental “Wow!” at a BBC story about the four galaxy clusters that go by the combined name of Pandora. The element of reporter Jason Palmer’s story that amazed me was not the almost incomprehensible concept of dark matter that was point of the account, but the size of everything. Palmer says: “Galaxy clusters are the largest structures we know of in the Universe, comprising hundreds of galaxies and trillions of stars - along with huge amounts of hot gas - and dark matter.”

The image of the Pandora cluster shows haphazardly scattered galaxies,

hot gas (false-coloured red)  and dark matter (blue) - BBC

To put that “trillions of stars” into perspective I went to one of the NASA websites NASA websites, which has these details about our own Milky Way: “The Milky Way is a gravitationally bound collection of roughly a hundred billion stars. Our sun is one of these stars and is located roughly 24,000 light years from the center of our Milky Way.”  That brought me up against another massive number – a  light-year is thedistance light travels in one year -  at the rate of 186,000 miles per second, or about six trillion miles: 6,000,000,000,000 miles.  That translates into approximately 10 trillion kilometers, or 300,000 kilometers a second.

COBE image of the Milky Way (Courtesy of Ned Wright), from the NASA website

NASA says the Milky Way galaxy has three major components:

    “A thin disk consisting of young and intermediate age stars - this disk also contains gas and is actively forming new stars. Dust in the disk makes it appear orange in the picture. Dust absorbs blue light more than red light and thus makes stars appear reddish. Our galaxy has spiral arms in its disk - these spiral arms are regions of active star formation.

   " A bar of older stars (white in the COBE picture).

   " An extended dark halo whose composition is unknown. Since the matter in the halo does not consist of luminous stars, it does not show up in the COBE image. The existence of the dark halo is inferred from its gravitational pull on the visible matter.”

The wonder of it all! However some people don’t bother to try to grasp this immensity, and others say “It’s big, but so what?” There’s more, too. I can’t see how all this is simply inevitable based on the belief that because gravity existed the Big Bang had to occur as a natural consequence.  How is it that a law of gravity should be proposed as an uncaused phenomenon when all our knowledge and experience is that there must a cause for everything ­- except God. 

The key idea is: "Because there is a law such as gravity, the universe can and will create itself from nothing." What an astounding jump in logic! The issue is kept in perspective by the results of a poll at The Guardian in Britain shown at the end of its article on Professor Hawking's latest book.