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Starry, Starry Night

February 16, 2004

by Peter Backus, Observing Programs Manager

After all these years, Im still surprised to see Orion nearly overhead.  It was one of the first constellations that I learned as a child.  From my backyard in Massachusetts, it passed through the cold, crisp winter nights about halfway up from horizon to zenith.  Until I went to graduate school, Orion always made the same familiar arc across the sky.  Then I traveled south about 1000 km to the National Radio Astronomy Observatory in West Virginia.  A change of a few degrees in latitude made a subtle but noticeable difference in Orions appearance.  A year latter brought me to a bigger telescope and a bigger change for Orion. 

Arecibo Observatory is in the tropics at latitude 18 degrees north.  My first trip here was quite an adventure.  It was my first flight on an airliner and my first time in a place where English was not the primary language.  Everything was a new experience: negotiating the fare for the publico (taxi), the vendors along the main road, the palm trees, and sugar cane fields.  However, the real surprise came in the early evening when we were dropped off in a parking lot in the city of Arecibo.  After setting down my luggage I looked up and there was Orion, nearly overhead.  I dont know how long I stared, but I eventually recovered enough to slowly scan my eyes south of Orion to discover stars I had never seen before.  Bright Canopus and dozens of fainter stars formed patterns I had only seen on star maps or in the planetarium.  I suddenly realized how far I had traveled.

Years later, with the first deployment of Project Phoenix, I got another perspective on Orion, a look from Down Under.  Australias Parkes Observatory is at latitude 33 degrees south.  From there, Sagittarius and the center of the galaxy pass overhead.  Orion is to the north and appears upside down.  I felt compelled to face south and bend over backwards to see Orion in the usual way.  After a few awkward attempts, I realized that was in my forties and would just have to get used to seeing Orion upended while at Parkes.

Now, nearly three decades since my first visit, Im back at Arecibo.  As I leave my cabin each night to take the midnight observing shift, I glance up at the familiar yet surprising constellation.  The bright stars of Orion are too massive and hot to host life-bearing planets, so they are not on our observing list. The astronomer in me knows this and considers the role of such massive stars play in creating the elements necessary for life.  The stars I see are young and scattered among them are smaller Sun-like stars that may have planets just beginning to form.  I also know that just beyond the stars of Orion lies a vast cloud with the mass of a million suns, and within that cloud a new generation of stars is forming.  This process has taken place throughout the galaxy over billions of years.  Thats what gives scientific basis for our search.  All the pieces are there in Orion.

I pull myself away from sight of Orion overhead and begin my walk down to the telescope.  Awaiting me is another eight hours in the control room, in front of the log book and computer screen.  But theres also the prospect of discovering life, perhaps not in the stars of Orion, but there are many stars shining in the tropical night.