An Astronomer's Thanksgiving
Every October, we Canadians celebrate our version of an old and traditional observance. For us, Thanksgiving is more of a harvest festival than a religious event, although churches usually take part in it. But we're grateful that we enjoy the freedoms and benefits of our wonderful country. Many of our ancestors survived harsh weather conditions, uncertain human relationships and inhospitable terrain. Canada's landscape is vast and often challenging. We've tamed what we could and left the rest to Nature's management. It seems to work quite well on the whole, with missteps that get noticed and resisted.
But today, I want to talk about what makes sky-watchers – astronomers, astrophotographers and star-gazers - thankful. Beyond the usual themes of food, faith and fellowship, what do we appreciate? I shall speak only for myself but hope that my thoughts will resonate with others as well. So … exactly what do I celebrate?
I'm grateful, first of all, to the ancient observers whose legacy I follow. The history of astronomy, and astrology too, is remarkable indeed. At one time, study of the heavens was both scientific, to acquire the knowledge that science embraces, and spiritual, to explain the will of divine beings through myth and legend. Many of our constellations and star clusters, as well as the planets of our solar system, are named for these mythical figures. The creatures of the zodiac can be counted among them, for they are archetypal animals or objects with specific qualities considered to be part of their essences. Today, astronomers use these old names dispassionately. We view them as convenient identification for star patterns. The gods, heroes and strange creatures are, to us, merely labels for structural elements that help us navigate the heavens.
Even "heaven" itself is a very old term. But it still works. The celestial realm, cosmos, universe, void … space itself. Poets use all of these. Our language allows for such variety. But most people just call it the sky.
So I thank the very oldest sky-students for all their work, their meticulous records, and sometimes their courage under adverse conditions. Not everyone trusted or welcomed them. Existing disbelief is a comfortable doctrine.
From 35,000-year-old marked bone sticks that tracked moon phases to the beautiful, German Bronze Age sky disk that even included a depiction of the Pleiades, ancient peoples have left artifacts that prove they were keenly aware of the starry realm above their heads. Stonehenge, after all, is quite probably an astronomical construction. Babylonian star catalogues dating to 1200 BC include Sumerian star names. Greek, Indian and Islamic astronomy were all grounded in Sumerian discoveries. Egyptian and Arab astronomers were both insightful and knowledgeable. They left a legacy of precise observations and many of our stars wear Arabic names, just as they did so long ago. And the Magi were astute sky-watchers. They understood what and where heavenly objects existed and they were quick to recognize anomalies. The Star of Bethlehem was most probably a supernova. It would have been immediately noted and intensively studied. Faith and science aren't always in conflict with each other. Sadly, this opinion isn’t universally held.
The heliocentric view of the solar system, in which planets orbit the sun, dates back far earlier than Galileo or Copernicus. Greek astronomers were a brilliant lot, whose keen minds and logical outlook brought many new ideas to the disciplines of science. Aristarchus of Samos, 300 years BC, postulated that the sun was circled by its planetary attendants. He also grasped the enormity of the universe; unfortunately, Ptolemy later shrank its size when he wrote the Almagest, although he did bring geometric astronomy into prominence for centuries thereafter. I am grateful for these fine minds and the groundwork they laid. I forgive them any inconsistencies or flaws. They lacked the instruments we now possess.
And then there were the Egyptians, whose great temples, erected in the third millennium BC, conformed to specific astronomical observations. The constellation Draco figured in pyramidal alignment to the Pole Star of that time, which was Thuban, not Polaris. When I consider the Draconid meteor shower, I feel somehow linked to people who lived and saw these same stars, almost 5000 years ago. I'm awed, humbled and inspired – all at once. Awe and humility seem necessary if we’re to grow.
Then there are the Chinese with their calculations, observations and star maps. They valued precision and their records are truly astonishing. They left records of supernovae which we can still use as reference data. And in the fourth century BC, the astronomer Gan De created the world's first star catalogue, still in existence. Meanwhile, in America, the Maya and Aztec societies were calculating solar calendars and tracking planetary movements. Then the Arab scientists drew upon existing knowledge, translated vast numbers of source materials, and identified supernovae, the Andromeda galaxy and many other celestial bodies. They introduced the laws of physics into the study of astronomy. They named many stars by which we remember them, and as I gaze at Mizar, Alnitak, Alnilam and Mintaka, Altair, Aldebaran, Alderamin, Deneb (dhaneb) and all the others with Arabic names, I'm thankful for the work done by these brilliant mathematicians and students of the skies. I put on this cloak handed to me by strangers’ hands, yet it feels right and familiar.
Therefore, I celebrate the knowledge of the Ancient Ones. I recognize its existence, in part, because it was preserved and enhanced by Roman astronomers and philosophers, who drew on Greek and Arabic works to extend their understanding of the universe. The wondrous star Capella, gleaming in the northeast like some sort of heavenly disco ball, immortalizes the name of Marianus Capella, Roman scholar and teacher whose legacy influenced thinkers of the Middle Ages. His remarkable book, De Nuptiis Philologiae et Mercurii ("On the Marriage of Philology and Mercury"), was a most unusual allegory that examined many academic pursuits. Two of these – astronomy and music – are among my heart's treasures. The influence of this enormous text carried on through the Middle Ages and into the early Renaissance. Indeed, "The universe, which has produced the bee-orchid and the giraffe, has produced nothing stranger than Martianus Capella". – C.S. Lewis
And I praise the memories of all those dedicated monks and other men of the Catholic faith who so laboriously copied information from an earlier day, so it could be preserved and passed down to us. They understood its critical importance to future generations and knew that it must be saved. The Dark Ages would have been even darker, had they not done so. The libraries of the Christian East, at SInai, stand as testament to the accumulated store of knowledge that these men recorded for all time. Astronomy was but one aspect of the great Saint Catherine’s collection, about which more information can be found here: https://www.loc.gov/collections/manuscripts-in-st-catherines-monastery-mount-sinai/articles-and-essays/microfilming-projects-at-mount-sinai-and-jerusalem/
But the centuries rolled on. Enter the Copernican Revolution, which turned the scientific world on its ear and introduced concepts that were to become integral to a growing body of knowledge based on observation, experiment and precise records of findings. Heliocentrism became widely accepted although Tycho Brahe deviated from this particular principle with a rather odd alternative theory. However, he also left meticulous detail which was utilized by Johannes Kepler, his successor. Ah, Kepler! I'm most appreciative of his incisive intellect. The three laws of planetary motion. The final confirmation, contrary to his predecessor’s argument, of a sun-centered system with planets in elliptical orbits around it. The early 17th century was a time of great change and ground-breaking discoveries. I bow to these individuals and their commitment to the progress of scientific understanding. It would have come eventually but thanks to their work, it came then and not later.
And then … Galileo.
What can one say about this man's achievements, short of writing yet another book about him? With a rudimentary telescope, he identified lunar craters, Jovian moons, sunspots and so much else. His book on these topics was banned during the Inquisition and he was declared a heretic for what he believed. The Church authorities wished to continue the fallacy that the earth was the centre of creation. He endured house arrest until his death – a man of courage, whose determination never wavered. He wanted to share truth. He felt it did not contradict faith. His is the name that reverberates down the ages, whenever spiritual teachings are raised in opposition to scientific explorations. And how deeply I revere that name.
Sir Isaac Newton is another sacred benefactor of our science. While Kepler explained how the planets moved, Newton showed us why this was happening. He combined physical laws with astronomical observations. He provided us with the mechanics behind the movements. Again, it would require many textbooks to fully encompass Newton's phenomenal contributions to the quest for knowledge. He, too, is a figure whom I view with the utmost gratitude and respect.
Then there are Halley and Herschel and all the others who continued to press for further awareness of our cosmos. And finally, there are the women! At last, their names are raised and known. They were there all along, but almost silent in the literature. They, too, would have stared into the night and chronicled the stars in their own fashion. And we will never learn the fullest scope of their influence – because they were women. Their efforts wouldn't have counted for as much as those of their male counterparts, back in their day. But they definitely count now!
Katherine Johnson, Mary Jackson and Dorothy Vaughn are household names now, thanks to their story as told in "Hidden Figures". NASA has raised women scientists to heights once undreamed-of. These three join Nancy Grace Roman – "Mother of the Hubble Space Telescope" – Margaret J. Geller, the universe mapmaker; Caroline Herschel, William's sister, who developed the NGC catalogue system of identification; the brilliant astrophysicist Cecilia Payne-Gaposchkin; the great Vera Rubin whose work affirmed the existence of dark matter and should have earned her a Nobel Prize … so many, many others. I don't often refer to a Wiki link in my blogs but this will be an exception. Each and every woman identified in this list can be further studied by clicking her name. https://en.wikipedia.org/wiki/List_of_women_astronomers
Among the women listed on that page, Hypatia of Alexandra remains one of my icons. She was an astonishing individual whose contributions to Ptolemaic thought and other scientific explorations are worthy of mention, many centuries after her death. She was murdered by Christians – a martyr to science. And science is under considerable threat for political (and religious) reasons in the present day. I will leave it at that.
My thankfulness is unbounded, however. I walk a road that has been made for me by the feet of countless pioneering men and women of intellect, imagination and intrepid commitment to their pursuit of discovery.
And now, today, this gratitude encompasses things as well as people. Galileo's modest telescope has given way to immense instruments that probe deep into the universe. I pore over their images in wonderment and awe. Astronomers across the globe share data among themselves and with the rest of humanity. Theories are propounded, discussed, examined and sometimes accepted - with support from a vast array of technological ammunition. From DSLRs to dew shields, spectrometry to spacecraft, we have an astronomical banquet within out reach. People have walked on the moon and plan an expedition to Mars. I see the ISS as it passes far above my delighted eyes. I dream and I dance.
My cameras and lenses have become irreplaceable companions as they, too, examine the night and record what it reveals. Every year, new developments yield better equipment, even for amateurs. Even for backyard astronomers like me. Much of it is somewhat affordable, albeit a budgetary stretch. Now the legions of astronomy fans and astrophotographers include a wide spectrum of us. We're not necessarily rich or highly-educated or famous. We're quite likely to be rather ordinary and unheralded, just folks, enjoying what we love.
I'm incredibly blessed by my friends in this field. Thanks to Tim Doucette, owner and astronomer of Deep Sky Eye observatory, I'm able to view the stars as I could never otherwise experience them. He's a mentor without equal and I've learned more than I could ever have thought possible for someone of my age. Because of Tim’s guidance and also his gear, I can navigate the night sky, identify its various features and share this information with visitors to the dome. I can work at mastering complex equipment, imaging and processing. Tim and his wife, Amanda, are amazing! His whole family is involved in this venture and they’ve welcomed me as a friend. They're super-special. I am blessed beyond measure to have met them and on Thanksgiving Day, to have been included at their feast.
So there it is – an astronomer's Thanksgiving. I could write a thousand pages but since this is already long enough for three blogs, I'll stop now. Needless to say, I owe a great many people a boundless debt of acknowledgement. And, as children of the universe in which we live, so do we all.