by Shane L. Larson
In the fall of this year, I turned 43 years old. Four days after my birthday I participated in a long standing tradition that has been handed down through many generations. It began 403 years ago, on a cool autumn evening in Padua, Italy. Galileo Galilei, then 45 years old, had crafted a simple telescope after hearing of the “spyglass” invented by the Dutch. Galileo was the first person to turn his telescope toward the sky, letting starlight flit through the shaped lenses and, for the first time, fall on human eyes. First light. Galileo beheld a Cosmos full of unexpected wonders, startling revelations, and new mysteries. Sweeping the faint glow of the Milky Way, easily visible in those bygone days before urban lighting, he discovered it was comprised of innumerable stars — more than he could sketch! He could see roughness and surface detail on the Moon, which up to that time had been thought to be perfectly smooth. Much to his surprise, he discovered that Venus had phases, like the Moon. And perhaps most importantly, he saw bright points of lights orbiting Jupiter — Galileo was the first person to discover other worlds in the Cosmos.
One of Galileo’s early telescopes.
Today, the heavens are more well known than they were 400 years ago, but still filled with grandeur, mystery, and awesome spectacle. Astronomy is an endeavour pursued by professionals, but also enjoyed by millions of amateurs worldwide, enabled by easy access to telescopes that Galileo would have loved to spend a few long evenings with, sweeping the heavens. For professionals and amateurs alike, we still celebrate the ritual of a telescope’s first night out under the stars.
First light. It is a magical time for any telescope — the first time it gathers starlight, and rather than let that light be absorbed by the Earth and pass into oblivion, it redirects it to a human eye, carrying the tales of the far away Cosmos. On a cool autumn evening, nestled down amongst the mountains of northern Utah, I turned a new telescope skyward for the first time. First light. The telescope was one of my own making, which I built based on the wisdom of others who had built telescopes before me, much like Galileo. I named it Cosmos Mariner.
My two telescopes. “Equinox” on the left, and “Cosmos Mariner” on the right.
Mariner is much larger than Galileo’s original telescope, and its optical elements were fabricated with higher precision than Galileo could have hoped to achieve in those early days. All told, Cosmos Mariner will gather about 500 times more light than Galileo’s original telescope, and can see objects about 25,000 times fainter than Galileo. And what awesome spectacles we beheld!
The first sight of the sky was the double star Albireo. The “head” of the constellation Cygnus, the Swan, Albireo lies nearly overhead as darkness falls at this time of year. It is a beautiful stellar pair, notable because it shows a striking amount of color — one star glows with a deep, yellow hue, while the other appears as a brilliant blue. My six year old daughter dutifully climbed the ladder, participating in this special night but perhaps not really knowing what to expect. She leaned over to the eyepiece and peered in. Through the gathering darkness, I heard her exclaim: “Pop! They have colors!” I could have quit then; First Light was a success. I often think back to that first night when Galileo turned his telescope to the sky for the first time. What did he look at? Was he by himself, or was someone there with him to share in the wonder and the spectacle?
The double star, Albireo (beta Cygni).
Our next stop was nearby, off the wing tip of Cygnus. There, nestled against the backdrop of the star studded Milky Way, a telescope will reveal the faint, gossamer light of the Veil Nebula. Peering through Mariner’s great eye, we could see faint tendrils and thin tracers of light, woven together in an intricate web of gas. The Veil Nebula is part of a much greater complex in the sky called the Cygnus Loop. It is a supernova remnant — the gaseous remains of a star that died in a titanic explosion some 8000 years ago. It is a doleful reminder that the stars also die, but that the Cosmos is beautiful and delicate even during the throes of destruction. The death of the stars is the beginning of new birth in the Cosmos — supernova explosions create the complex chemical elements that make up worlds like the Earth and beings like you and I. The gas and dust that we see today as the Veil Nebula will someday merge with other vast clouds in the Milky Way and collapse under gravity’s inexorable pull until it explodes with the birth a thousand new suns.
The eastern portion of the Veil Nebula.
Our last stop of the evening was high in the eastern sky, nestled just below the neck of Pegasus. Turning Mariner’s gaze toward that distant corner of the sky revealed the diaphanous glow of a galaxy that astronomers call NGC 7448. Mariner revealed a faint, glowing oval of light with a brighter orb of luminosity embedded at its center — a spiral galaxy, not unlike our own home, the Milky Way. There are other brighter galaxies in the sky to see, but on this night I wanted to see this galaxy, because the light from that distant island of stars left its home 100 million years ago, departing for Earth at a time when dinosaurs still roamed our small blue world. It astonishes me still that I can just now capture that light tonight, drinking in the photons through my eyes, and converting them into evanescent memories.
The spiral galaxy, NGC 7448, 100 million light years away from Earth.
The telescope is magic in its rarest and purest form, a device brought to life by human ingenuity and creativity. Telescopes expand our vision beyond the small confines of our world to distant corners of the Cosmos, showing us vistas that challenge the boundaries of ordinary human comprehension and force us to think deeply about our place in the grand design.
The great secret of telescopes is that they all will show you more of the Cosmos than your eyes alone will. The cheap pair of $10 binoculars you have under the seat of your car is a far superior astronomical instrument than Galileo’s original telescope. For the cost of two or three months of your cell phone bill, you can own a 6-inch telescope that will reveal thousands of distant galaxies, swirling nebulae, the enigmatic surface of Mars, and the beautiful choreography of binary stars. Large telescopes, like Mariner, are becoming more and more common, providing views that would have made Galileo swoon.
Take a moment tonight, and go out and look at the stars. Turn off your back porch light, and drink in the starlight that has been hurtling toward the Earth since before you were born. Make your own First Light, and ponder the deep connection we share with the Cosmos. And if you’re ever in my neck of the woods, let me know; we’ll pull Mariner out and celebrate in the starlight together.
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