Sky's Up July - September 2018 | Page 46

features in enough detail so that they might be published in books and newspapers of the day. The photos made by Lowell and his assistants electrified the public as well as the scientific community. Here however, Percival Lowell made an error that has sullied his reputation as a scientist and astronomer. Rather than offer the photos as a scientific achievement in and of themselves, Lowell insisted that the photos provided evidence for the existence of the Martian canals and the Dying Planet hypothesis. Lowell’s scientific critics treated his ideas respectfully, exploring them, trying to replicate his results and offering challenges to his theories based on new data and observations from astronomers around the world. By the end of Lowell’s life in 1916, it was clear to most of the scientific community that in spite of Lowell’s magnificent achievements in observation and photography – his theory of giant canals on a dying desert planet were just not true. The popular imagination and press were not as ready to drop the dying planet idea, however. From H.G. Wells’ War of the Worlds (and the many films and radio plays based upon it), to the John Carter Mars novels of Edgar Rice Burroughs and thousands of science fiction stories and hundreds of films, Life on Mars lived on in popular culture. In 1964, Mars exploration entered a new era; the Mariner 4 probe flew past Mars for the first time and sent close up photos of the red planet back to Earth. These photos were relatively poor by today’s standards, but they represented the very first time that humans had sent a spacecraft to another planet and sent back relatively close-up photos of the surface. The Mariner 4 photos showed a dry, cratered world that looked far more like the Moon than the Earth – and the Dry Mars hypothesis was 46 Nonprofit is giving historic telescope a second life By DR. DANIEL BARTH Guest Contributor COURTESY OF NASA Above, this image of Mars was taken by Mariner 4. Below, this image of a river bed on Mars was taken by the Viking orbiter. Percival Lowell worked with his assistant Carl Lampland to capture the first high resolution images of Mars. born. Mars was now officially a dead planet, waterless, and therefore lifeless as well. Not only was there no sign of any sort of life, there were no indications of anything remotely like canals stretching across the surface. Even when the Viking spacecraft — an orbiting photographic satellite and a stationary lander — sent photos back of dry river beds, ‘splash craters’ that looked like a rock thrown into a shallow mud puddle and other evidence of a wetter ancient past, these photos were dismissed. Dry river beds could never have held water because Mars was dry! Evidence from the two Viking landers that seemed to indicate the presence of microbial life in the Martian soil was also dismissed. No water, no life! had become the official scientific doctrine of the day. Percival Lowell had been wrong, and that was that. The 21st century again brought a new era to Mars exploration — the rovers had landed! The first primitive Pathfinder rover touched down on Mars in 1997, but the real exploration began with the arrival of the Spirit and Opportunity rovers in 2004. Opportunity, which is still actively exploring Mars today, discovered COURTESY OF NASA evidence that liquid water had once flowed on the Martian surface, and the Curiosity rover found chemical evidence that water in the Gale Crater region had been much like water you might find in a lake or stream on Earth today. Ancient Mars had been “warm, wet, and habitable” according to NASA scientists. The Dry Mars hypothesis was officially dead. Today we know Mars better than ever before. It is a cold, desert planet with oceans of water locked in frozen glaciers beneath the surface. Mars is a place where liquid water is thought to bubble out and occasionally flow in brief spurts across the sands of south- facing slopes in springtime. There are many mysteries to still left to explore on Mars. Why did the atmosphere become thin and cold? Was there ever life on the Martian Sky ’ s Up The 24-inch refracting telescope commissioned by Percival Lowell in 1894 from Alvin Clark and Sons was one of the largest, and finest telescopes of its day. This giant refractor was more than 36 feet long with a primary lens 24 inches in diameter. It was with this great telescope that Percival Lowell made his famous sketches of Mars, and through this great lens, he took the first clear photographs of another planet. The great 24-inch refractor was also used to map the lunar COURTESY OF Swarthmore College surface in detail for the first NASA The historic 24-inch Sproul Telescope was recently relocated from Swarthmore College landings on the Moon in the 1960s in Pennsylvania to Northwest Arkansas.. The nonprofit Supporting STEM and Space and it did early work on discovering Foundation is refurbishing the refractor with plans to make it the showpiece of an exoplanets — planets orbiting distant observatory in the works for Northwest Arkansas. STEM and Space Foundation acquired this great stars many light years from our Sun. telescope, which is now undergoing renovations Today, all modern research telescopes are and will soon be put back into service at a planned reflecting telescope designs, using great mirrors observatory site in Northwest Arkansas. to gather and reflect light. Although the era of It is a tribute to the Supporting STEM and Space large refractors in science is over, there is a twin Foundation, Explore Scientific and their many to the great Lowell Observatory refractor – the public and corporate sponsors, that this piece of Sproul Telescope. The Sproul Telescope is also America’s scientific heritage wi ll soon be back a 24-inch refractor design, fully 36 feet long, in service; inspiring young and old alike with originally constructed by the Brashear Company magnificent views of the Moon, Mars and beyond. in 1911. Recently, the nonprofit Supporting This panoramic image of the Martian surface was captured by the Opportunity rover in 2007. surface? How did the planet’s climate change over billions of years? Is there still a water cycle on Mars as there is on Earth? Some of the Mars explorers will Sky ’ s Up get to drive rovers, or command photographic satellites orbiting the red planet. But most of the Mars explorers during this year’s great opposition will be like you and me COURTESY OF NASA – sitting in our backyards on warm summer evenings, looking through our telescopes at a distant, cold desert world that still has the power to fire our imaginations and stir our hearts. 47