Star Trails 101
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It's late on a Saturday afternoon in downtown Jerusalem, perhaps 2500 years ago. A man stands outside the Temple, anxiously looking upward. He sees a bright star rising in the east, and a second one overhead. This man knows the sky well, and as he turns to the Northwest, he glimpses Capella in the gathering darkness. "That's it!" he thinks. Three stars have appeared, and that ancient Sabbath of millennia ago has ended. Although the Jewish tradition of sighting stars is no longer generally practiced, it dates back to the dawn of skywatching. On cloudy nights, the observer would look at two strings, one white, one blue, and would judge the sabbath over when he could no longer tell their colors apart. All of Judaism is based on a lunar calendar. For many of us, the sky goes beyond equations; our interest in the night sky has a strong spiritual component, whether it is the sighting of three stars or the phase of the Moon. I realized this many years ago, on the eve of Judaism's holiest day. Kol Nidre evening, a long and beautiful service, is known for some of the most soaring music of the Jewish liturgy, but for me its meaning extends literally to the sky. While walking home after one of these services, I noticed the bright 10 day old gibbous moon dominating the evening sky, its impact craters Copernicus and Tycho having just seen sunrise after their frigid two-week night. I realized that the Moon displays the same phase every Kol Nidre night, and has through the ages. That moonlit walk home joined my senses of science and spirituality. That sense of spirituality is strong in our family, six generations of which have been with Congregation Shaar Hashomayim. This synagogue, whose name means Gates of Heaven, is celebrating its 150th anniversary this year. William Levy, my grandfather, helped design the sanctuary which was built in 1922. The synagogue is especially known for its exquisite choir, whose renderings of Jewish liturgical music have made Sabbath and holiday services a joy to attend. When I am hunting for comets late at night, I often think of the choir's renderings: they end so beautifully and peacefully that they almost command their listeners to look up. Having a spiritual sense of the sky is not just a feeling. In Judaism the relation is a literal one, since the calendar is based on the orbit of the Moon about the Earth. It is not a coincidence that the Moon is always 10 days old every year after Kol Nidre services, nor is it by accident that the total lunar eclipse of April 3 this year took place on the first Passover seder, which always occurs on the night of full Moon. This spring's eclipse is one of several I have seen during the first night of Passover; in 1968 I rushed away from a seder early to catch one. A culture so closely connected to the sky will go more deeply than moon phases. The first book of Chronicles describes what could be a comet-- the comet of 971 BC appeared near that time-- which protested an ill-advised census King David had ordered. The biblical passage is read every year at the Passover seder: "And David lifted up his eyes, and saw the angel of the Lord standing between the earth and the heaven, having a drawn sword in his hand stretched out over Jerusalem." Connecting the words of liturgy to a love of the sky is easy, as anyone who has attended Stellafane knows. But though the words are there, the feeling more complicated. "The Heavens declare the glory of God," trumpets Psalm 19; these words remain prominently inscribed on the clubhouse through sixty years of telescope conferences. Russell Porter, Stellafane's 1920s founder, took those words very seriously even though he was not an active churchgoer. In his biography of Porter, Berton Willard noted that "One Sunday morning when he and Oscar Marshall were heading for the clubhouse, they were approached by a deacon and asked whether they were going to church. Porter replied they were going to Breezy Hill and would not make any noise that would disturb him. He also reminded the deacon of the inscription on the gable of their temple to the stars." Porter felt that there was no place closer to his spirit than an observatory like Stellafane. Years later and a continent away, he built the telescope at Palomar that the Shoemakers and I used in our comet discoveries. In all the many hours we worked there, my favorite part was when the dome shutters started to open, slowly revealing a darkening sky. No matter how busy the next 13 hours of photography would be, I cherished the minute that passed by as the opening shutter cajoled the sky to enter. It is a spiritual feeling that can separate from a specific religious belief, but doesn't have to be, and I am sure many skywatchers, regardless of their religious feelings, have a similar experience at the start of a beautiful night. Equations can explain the physics of what we see in the night sky, but the wonder goes beyond the numbers. Each of us has a personal reason for enjoying the precious beauty of the night sky. For some, the background of a religious liturgy helps. The Jewish framework is its ancient tradition of a nomadic people that depended on the Moon for their calendar. It was also a part of that tradition that the Sabbath and festivals ended after an official observer noticed that the evening sky was dark enough that three stars had appeared. That man who stood outside the Temple in Jerusalem, waiting with anticipation for the sky to darken so gradually and carefully until three stars appeared, must have felt his cosmic role. Sabbath would not end until the sky presented him with three stars. It must have been a singular and personal way to get acquainted with the sky. Seeing that third star must have felt as wonderful as discovering a comet. (c) Sky & Telescope, 1996