Moon a wonder for effect on Earth, us
By Amanda Jermyn



Reach for the Stars… September 2009
Amanda Jermyn
Recently the Spitzer Space Telescope detected a collision between an object the size of the moon and one the size of Mercury orbiting the young star HD172555, a mere 100 light years away. Analysis of the infrared light spectra of the star showed amorphous silica, in other words, glass! The formation of this glass, probably in the form of blobs called tektites, tells us the collision must have been massive, and the detection of silica tells us that it happened fairly recently, probably a few thousand years ago. Violent stuff happens in space all the time, sometimes in our own celestial back yard. Over 4 billion years ago a Mars-sized object collided with earth, spewing debris into space to form our moon. But what if it hadn’t happened? Where would we be without the moon? In a darker, less romantic place, for sure, but what else would be different? Without the moon there would be no tides. These are caused by the gravitational pull of the moon on the water as the earth turns. Without tides the evolution of life might not have occurred or might have taken a different turn. It has been theorized that tidal waters flowing over clay and sand may have created the right conditions for life to emerge from nonliving matter, and that the tidal zone, where water is only sometimes present, may have helped create the impetus for land plants and animals to develop from sea plants and fish. Our moon may also act to steady the earth’s axis, saving it from wild tilts over millions of years that could create extreme weather fluctuations hostile to the development of life. Without the moon our earth would likely rotate faster, causing a more turbulent atmosphere and extreme winds hostile to life. Without the violent collision that created our moon we would probably not be here. Thanks to the moon we can savor romantic evenings in all their shimmering beauty, and the gift of life itself.
For more on the wonders of the night sky, join the Springfield STARS Club for a talk by guest speaker Kevin Collins on his trip to the Kennedy Space Center to view the launch of the space shuttle Atlantis this past May. Kevin will talk about the logistics of attending the launch, describe the shuttle stack, the launch itself, and the mission to service the Hubble Space Telescope, the primary goal of this venture. Kevin has a degree in geosciences and works as a database and web application developer. He is vice president and web developer of the Amherst Area Amateur Astronomers Association, a member and graduate of the Star Watch program at Arunah Hill, and vice president of the Astronomy Association which works to foster interaction and mutual support among member clubs in the Springfield and Amherst area. Kevin is an avid amateur telescope maker and has organized numerous star parties in the region. His talk for the Springfield STARS Club will be held on Tuesday, September 22nd at 7.30pm in the Science Workshop next to the Planetarium at the Springfield Science Museum at the Quadrangle. Refreshments will be served, and the public is welcome free of charge.

Amanda Jermyn, of Longmeadow, has been a member of the Springfield Stars Club since 2000 and currently serves on the club's board of directors. For more information, visit the Springfield Stars Club Web site at www.reflector.org or call 1(800)336-9054.