Get Ready for the 2018 Mars Opposition
What Makes Mars So Interesting?There are many, many answers to that question, but let us start off from the perspective of our ancient ancestors who did not have access to telescopes or a detailed knowledge of what the various lights in the night sky were. Our ancestors did recognize that most of those lights stayed in fixed positions with respect to one another, but a few of these lights wandered among the others. The modern word planet actually derives from the ancient Greek "planētes asteres," or wandering stars. The five classical planets, Mercury, Venus, Mars, Jupiter and Saturn, were all known to the Babylonians, perhaps as early as 2000 BC. The closest of these, Venus and Mars, may have been of particular interest because of the speed and apparent distance of their wandering among the stars vs. the more distant Jupiter and Saturn. In 2018 Mars will move from a position near the cap of the teapot in Sagittarius to one near the circlet in Pisces, which is a considerable distance. Venus and Mars also undergo much larger changes in size and brightness than the other classical planets, which made their wandering even more evident. The Egyptians recorded observations of Mars as early as the second millennium BC, and the Babylonians recorded detailed observation of the orbit of Venus in the 7th century BC. Mars and the other classical planets all held special places in mythology. Venus, being pure white, was associated with purity and the God of love. Mars, being red, was most likely associated with blood and warfare. The Babylonians, Greeks, Romans and even Hindus all identified Mars as the God of war. Both the red color and large change in visual magnitude no doubt contributed to this. Mars started 2018 at magnitude +1.5 and will reach a peak magnitude of -2.78 at the end of July, corresponding to more than a 4x change brightness as perceived by the human eye in just seven months time. Mars in the Age of ScienceWith the invention of the telescope our knowledge of Mars rapidly advanced. Within a century of that invention the polar caps of Mars had been observed. Unfortunately not all observations were completely accurate. In 1877 the Italian astronomer Giovanni Schiaparelli observed and recorded straight lines along the equatorial regions of Mars, which he referred to as "canali." Unfortunately what he thought he saw was an optical illusion. Even more unfortunate, however; the Italian word canali was mistranslated into the English word canal, and the notion of an intelligent civilization on Mars was born. While Schiaparelli's observations started the notion of Martian canals, it was the American astronomer Percival Lowell who really ran with the idea. Lowell observed Mars with great enthusiasm, beginning in 1893. He built the famous Lowell Observatory in Flagstaff, AZ in 1894 to continue his studies from an ideal location, and later went on to write three books on Mars. The titles included Mars (1895), Mars and Its Canals(1906), and Mars as the Abode of Life (1908). Lowell did more than any other single person to popularize the notion of life on Mars. Lowell went further, concluding in his publications that the Martian canals were built and operated by an intelligent civilization. As the science of astronomy continued to advance in the twentieth century, the notion of a civilization on Mars receded. The surface temperature of Mars was measured in the 1920s to range from −121 to 45 °F. By the late 1940s the composition of the thin Martian atmosphere had been measured and showed only trace amounts of oxygen and water vapor. In spite of this, the notion of canals on Mars endured within the astronomical community up until the 1960s. One thing we can credit Lowell with is the inspiration for several classic pieces of science fiction, including H. G. Wells' "War of the Worlds." Mars in the Modern EraOur view of Mars changed dramatically with the Mariner 4 mission. Launched from Cape Canaveral on November 28, 1964, Mariner became the first spacecraft to take pictures of another planet from space on July 15, 1965. Those grainy black and white images returned from Mariner 4 put the notion of an intelligent civilization to bed forever. Our romantic view of Mars made popular by Percival Lowell gave way to that of a lifeless body far more similar to our own moon. Mars has proven to be a difficult planet to reach, and more difficult to successfully land upon. Prior to the Mariner 4 flyby, six other Soviet and US missions to Mars failed to reach the planet. The first successful landing occurred with the Soviet Mars 3 mission launched on May 28, 1971. Unfortunately communications were lost only 14.5 seconds after landing. The US Viking 1 mission, launched on August 20, 1975, was the first fully successful landing mission sending back the first clear pictures from the surface of Mars. There have been many other robotic missions to Mars in the years since then, including ten attempted landings and one additional lander en route. At present there are eight operation robotic missions studying Mars, including two rovers and six orbital probes. Six countries and international consortiums have launched missions to Mars within the past twenty years. Why So Much Ongoing Interest in Mars?Simply stated, Mars is the most Earth like planet within our solar system, not to mention reasonably close and also feasible to reach with our current technology. It stands to reason that when mankind extends its permanent habitat beyond Earth, Mars is the most likely candidate for that habitat. Percival Lowell may have been wrong in terms of his conclusions of an intelligent civilization on Mars, but the potential for extending our own civilization to Mars seems very real. The summer of 2018 represents one of the best opportunities ever afforded to observe Mars, so don't miss out! Coming Up NextOur next edition will focus in on tips for observing Mars, including equipment, techniques, and planning tools. Further ReadingThe Canals of Mars The Lost Canals of Percival Lovell |