Wayward Comet:. Martin Beech

      INTRODUCTION

      Comets have been celebrated and revered throughout all human history, and they are as old as the solar system itself. Indeed, comets, or more specifically the icy nuclei that constitute the heart of the cometary display, are older than the Earth. Literally giant icebergs in space, cometary nuclei were among the firstborn, being the icy planetesimals that grew in the frigid bulk of the nascent solar nebula. Cometary nuclei coalesced in the primordial alchemy that took place 4.56 billion years ago, and they have harassed and hydrated the Earth and planets ever since – indeed, since the proverbial day one they have spread long bedazzling tails across the darkness of the night sky.

      Most comets appear entirely at random; they are renegades that work against the clockwork certainty of the celestial sphere. Mercurial, temporary, different and unlike anything else in the heavens, humans could not fail to find comets strange and unsettling – they literally and figuratively rebel against the order and permanency of the stars. Perhaps it was some ancient rumor or mythological-twisting of a past collision that resulted in comets being cast in the role of unwelcome strangers; for certainly, from the earliest of surviving records, the sighting of a new comet has invariably been taken as a cause for concern. We may well wish upon a falling star, but the sudden appearance of a comet is not something to be wished for. Portentous messengers of doom, especially for any ruling aristocracy, Shakespeare reminds us that comets are a special heavenly sign, “when beggars die there are no comets seen; the heavens themselves blaze forth the death of princes”. In parallel sympathy, Erasmus, that great medieval humanist, impressed upon society, with both ancient and modern-day resonance, that only by “the good influence of our conduct may we bring salvation to human affairs; or like a fatal comet we my bring destruction in our train”. Indeed, comets have long taken the rap for instigating extraordinary earthly proceedings – being cast as the purveyors of famine, the bringers of war, the harbingers of political downfall, and the agents of flood, drought, and plague.

      Victorian novelist Thomas Hardy, who was well read in astronomy, further deepens the mystery of comets when he describes their properties as being “erratic, inapprehensible, [and] untraceable” [1]– all characteristics that run counter to the human ideal of a world full of order, understanding and certainty. Indeed, public suspicion (and gullibility) runs deep when it comes to comets. The great Christian apologist C. S. Lewis portrayed a lurking comet in his science-fiction work, Out of A Silent Planet (first published in 1938): the book’s philologist hero Dr. Elwin Ransom seeing, on his way to Malacandra (the planet Mars), against a backdrop of splendid stars and majestic planets, a “comet, tiny and remote”. Here the comet image is one of implied malevolence, a cowardly evil ready to stir-up trouble when the time is right. Never was comet-angst and disharmony more rampant than during the 1910 return of Halley’s Comet. People fretted over the uncertainty of what might happen as the Earth traversed its extended tail, and the ‘snake oil’ industry went into overdrive. A comet-born demon was about to be unleashed upon our hapless globe, and only the well-prepared and cautious would survive the ordeal. The comet-sent killer, an invisible and silent stalker, was to be the deadly gas cyanogen (HCCN), a molecule that spectroscopists had previously identified within cometary light. Clearly, many reasoned, therefore, all humanity was to be asphyxiated when the Earth swept through the comet’s noxious out-gassings – it was literally the sting in the comet’s tail. Panic, of a sort, ensued and sugar-coated quinine pills, along with mouth inhalers and gas masks could be purchased to ward off the deadly effects of the comet’s emanations. Submarines were made available for hire so that the discerning few might ride-out the encounter under the safety of the ocean waves, for indeed, as one newspaper clipping extolled, “deadly cyanogen gas does not travel through the water”. In Arizona “comet proof” rooms were constructed by the Malapai Mining Company – guests, the Arizona Republican newspaper for 16 May reported, would be walled-in for 10 days in order to “counteract any poisonous comet gas”. For those more inclined to celebrate the end of days, however, other products were made available to ease their would-be passage into the afterlife – for the hard drinker there was Comet Whiskey, especially distilled by Bernheim Brothers in Louisville, Kentucky; the more bohemian of taste could imbibe a Halley Highball or a Cyanogen Flip. If drinking was not a personal preference, then the more temperate in nature could while away their final hours to the rolling refrains of Ed Mahoney’s especially composed Comet Rag. At other times in history the hapless comet observer could have consoled the desperation of existence by taking a sip of prized comet wine [2] - but history tells us that 1910 was not to be a vintage year. The grapes did not wither upon the vine as Earth passed through the tail of Halley’s Comet on 19 May 1910, nor, for that matter, did they especially flourish, but no one died of cyanogen poisoning. Deaths, however, were reported, with a desperate few choosing to take their own lives before cometary devastation descended upon the Earth. Eighty-seven years later the same sad story played itself-out when comet Hale-Bopp came in from the frozen depths of the outer solar system. Lost to the resources of sensibility and apparent reason, 39 members of the Heaven’s Gate Cult tragically committed mass suicide on 26 March 1997, convinced that they would be teleported to salvation aboard an alien spaceship that was following the comet towards the Sun [3].

      In contrast to the news that was to prevail in 1910 and the Heaven’s Gate tragedy of 1997, renowned author H. G. Wells chose to run against tradition in his short novel In The Days of the Comet (published in 1906). For Wells the nameless comet was a catalyst, with the storyline seeing the Earth pass through its gaseous tail and thereby ushering-in a wonderful atmospheric transformation. Echoing ideas popularized by Isaac Newton in the early 18th Century, Wells had the comet invigorate Earth’s atmosphere: “the nitrogen of the air [was changed into] a respirable gas, differing indeed from oxygen, but helping and sustaining its action, a bath of strength and healing for nerve and brain”. In short, because of the comet encounter Earth’s atmosphere becomes a kind of happy-gas, resulting in the end of war, hatred and strife. The chemistry and transformation, of course, is nonsense, but it enables the story to develop. Indeed, In The Days of the Comet is one of Wells’s more gentle works [4], evoking as it does, the development of a Utopian society that actually appears to work – a conclusion at odds with his more famous earlier work The Time Machine (published in 1895).

      Writing several decades before Wells’s The Days of the Comet, Jules Verne explored the consequences of an Earth grazing encounter (which supposedly took place on “January 1, 188x”) in his 1877 novel, Off on a Comet. The comet, given the name Gallia, causes a fragment of the Earth to be launched into space, and the story follows the journey undertaken by the hapless survivors. The Earth-fragment undergoes a miraculous and astronomically revealing tour of the solar system, and exactly one year after being launched it returns to the Earth’s orbit – at which point the survivors return to terra firma by hot air balloon. As with most of Verne’s fantasy stories many facts and numbers are presented, but, too admittedly over nit-pick, it is clear that he woefully misunderstood cometary orbits and Kepler’s laws. The intriguing aspect of the comet inspired