So, here is the more appropriate update for the recent Mars discovery. The discovery of perochloridate salts in the seasonal flows on Mars, hence indicating the presence of ( briny) liquid water on the planet, is a tremendous discovery. However, it confirms previous observations that water was present on Mars, in one form or another. Not on the surface, obviously. It is too cold on the surface for liquid water to exist as a liquid. However, it likely existed billions of years ago, and it might exist subsurface, where the seasonal flows likely come from. And if water, however salty, exists, the chances of life of some form existing on Mars does increase. Of course, this mode of thinking is only around 50 years old. From the time of William Herschel (who was the first to demonstrate that the white parts of Mars were ice sheets), it was believed that water, and presumably life, was abundant on Mars. Especially with the presence of the icy poles. In fact, a dark shadow that would go from the pole to the Equator was considered to be a seasonal plant growth in the late 19th and early 20th century (Astronomer Gerard Kuiper would say that the dark spot was windblown dust, and this hypothesis was later confirmed by Carl Sagan, and his student James Pollock). And the idea of life on Mars was ingrained, actually still ingrained, in our fiction. The aliens that invaded late Victorian England in H. G. Wells' War of the Worlds were Martian in origin. In Edgar Rice Burrough's Barsoom series (which you may know from that overall descent, but disappointing film John Carter a few years ago), was full of various races and creatures roaming the planet Mars. And there are many other examples, from Tweel in the 1934 short story Martian Odyssey (it's in public domain, so you might be able to find it) to Looney Tunes' Marvin the Martian. The biggest influence on all of these ideas was a man named Percival Lowell, and his ideas about Martians using canals to transport water.
Well, I call them in the title "his canals", but Lowell didn't actually discover them. They were first described by an Italian astronomer named Giovanni Schiaparelli, during the Opposition of 1877. Basically, when Mars is on the opposite side of the sky from Earth. He had drawn several extensive straight lines on Mars, which he described as canali. Before I go any further, I would like to put that particular term into context. Apparently, while it is spelled like canal, the word "canali" actually roughly translates to channel, as in a natural channel. Schiaparelli also never hypothesized that they were artificial in origin, though he didn't oppose the notion. However, in the Anglosphere, the term canali became canal, and soon, it became a very popular idea that canals existed on Mars. Then came Percival Lowell, whose name would come to be associated with the canals. Lowell was not a professional astronomer. He was a business man and diplomat by training, and Harvard educated to boot. After hearing about Schiaparelli's discovery in 1893, he set out to discover see them himself. He built his own observatory in Flagstaff, Arizona, and looked at Mars, and drew the canals that he found. Using these, he concocted an entire story, (based in part on William Pickering's speculation on the canals) about a civilization which was dying due to a lack of water. They needed to transport the water via canals to keep them alive. He popularized this particular story in a large variety of books and articles on the topic, where the idea of Martian canals was disseminated into the general culture. He would promote these ideas until his 1916 death. Note that this was the time that technological progress of all kinds, particularly transportation, were being celebrated, so the public was ripe for this idea, much as ancient aliens appeal to modern audiences.
Despite the popularity of the canal hypothesis, professional astronomers were skeptical. Why? They couldn't see them! No professional astronomer could actually see or describe the canals. Astronomers like Asaph Hall (who discovered the Martian moons), and Edward Bernard (who discovered Amalthea, one of Jupiter's moons.) viewed the Planet and couldn't find any of the canals Lowell described. Other, non-astronomers also criticized Lowell. In particular, was biologist Alfred Russel Wallace, who was notable in formulating the theory of evolution independently of Charles Darwin, and influencing him to some extent. In 1907, Wallace wrote a rebuttal against Lowell, and his theories, noting that the so-called “canals” are likely just cracks in the Martian crust, where volcanic carbon dioxide rises from the mantle of the planet, and into the plants on the surface. Even if this explanation wasn’t true (its validity based on the idea that Mars had non-contracting core inside a contracting crust), Mars also had a mean temperature of -35 F, far too cold for any life to exist. And in In 1909, during an observation in a thirty-three telescope in Meudon, France, astronomer Eugene Antoniadi proposed that the canals were optical illusion, based off the fact that the surface of the planet were naturalistic. Despite the rejection of the mainstream astronomy community, the canals of Mars persisted into the 1950's. Werhner von Braun mentioned them in his Mars work, and Ray Bradbury was influenced to some extent by Lowell, when he was writing the Martian Chronicles. However, it was the arrival of Mariner 4 to the Red Planet in 1964 that finally killed off the idea of Martian canals. It not only showed that Mars was virtually dead, but there were no canals at all, confirming the observations of the astronomers of Lowell's time.
So, what were some good things to come out of this? Well, towards the end of his life, Lowell would turn his attention towards a ninth planet, which he called "Planet X", which he and the observatory at Flagstaff would try to find. Eventually, in 1930, an astronomer working at the Flagstaff observatory (at this point named the Lowell Observatory) named Clyde Tombaugh discovered Pluto, and the initials PL (as in Percival Lowell) was chosen as its sign. Also, it did popularize the idea of water on Mars. Further, Schiaparelli's initial idea of "canalis" as natural features have been shown in the form of various channels and canyons, which were more than likely formed from the erosion of liquid water in the distant past. While there were no dying civilizations or large artificial canals, this weeks discovery does demonstrate that water does exist on Mars, and with water, there is the possibility of life on Mars...
Sources:
Well, I call them in the title "his canals", but Lowell didn't actually discover them. They were first described by an Italian astronomer named Giovanni Schiaparelli, during the Opposition of 1877. Basically, when Mars is on the opposite side of the sky from Earth. He had drawn several extensive straight lines on Mars, which he described as canali. Before I go any further, I would like to put that particular term into context. Apparently, while it is spelled like canal, the word "canali" actually roughly translates to channel, as in a natural channel. Schiaparelli also never hypothesized that they were artificial in origin, though he didn't oppose the notion. However, in the Anglosphere, the term canali became canal, and soon, it became a very popular idea that canals existed on Mars. Then came Percival Lowell, whose name would come to be associated with the canals. Lowell was not a professional astronomer. He was a business man and diplomat by training, and Harvard educated to boot. After hearing about Schiaparelli's discovery in 1893, he set out to discover see them himself. He built his own observatory in Flagstaff, Arizona, and looked at Mars, and drew the canals that he found. Using these, he concocted an entire story, (based in part on William Pickering's speculation on the canals) about a civilization which was dying due to a lack of water. They needed to transport the water via canals to keep them alive. He popularized this particular story in a large variety of books and articles on the topic, where the idea of Martian canals was disseminated into the general culture. He would promote these ideas until his 1916 death. Note that this was the time that technological progress of all kinds, particularly transportation, were being celebrated, so the public was ripe for this idea, much as ancient aliens appeal to modern audiences.
Despite the popularity of the canal hypothesis, professional astronomers were skeptical. Why? They couldn't see them! No professional astronomer could actually see or describe the canals. Astronomers like Asaph Hall (who discovered the Martian moons), and Edward Bernard (who discovered Amalthea, one of Jupiter's moons.) viewed the Planet and couldn't find any of the canals Lowell described. Other, non-astronomers also criticized Lowell. In particular, was biologist Alfred Russel Wallace, who was notable in formulating the theory of evolution independently of Charles Darwin, and influencing him to some extent. In 1907, Wallace wrote a rebuttal against Lowell, and his theories, noting that the so-called “canals” are likely just cracks in the Martian crust, where volcanic carbon dioxide rises from the mantle of the planet, and into the plants on the surface. Even if this explanation wasn’t true (its validity based on the idea that Mars had non-contracting core inside a contracting crust), Mars also had a mean temperature of -35 F, far too cold for any life to exist. And in In 1909, during an observation in a thirty-three telescope in Meudon, France, astronomer Eugene Antoniadi proposed that the canals were optical illusion, based off the fact that the surface of the planet were naturalistic. Despite the rejection of the mainstream astronomy community, the canals of Mars persisted into the 1950's. Werhner von Braun mentioned them in his Mars work, and Ray Bradbury was influenced to some extent by Lowell, when he was writing the Martian Chronicles. However, it was the arrival of Mariner 4 to the Red Planet in 1964 that finally killed off the idea of Martian canals. It not only showed that Mars was virtually dead, but there were no canals at all, confirming the observations of the astronomers of Lowell's time.
So, what were some good things to come out of this? Well, towards the end of his life, Lowell would turn his attention towards a ninth planet, which he called "Planet X", which he and the observatory at Flagstaff would try to find. Eventually, in 1930, an astronomer working at the Flagstaff observatory (at this point named the Lowell Observatory) named Clyde Tombaugh discovered Pluto, and the initials PL (as in Percival Lowell) was chosen as its sign. Also, it did popularize the idea of water on Mars. Further, Schiaparelli's initial idea of "canalis" as natural features have been shown in the form of various channels and canyons, which were more than likely formed from the erosion of liquid water in the distant past. While there were no dying civilizations or large artificial canals, this weeks discovery does demonstrate that water does exist on Mars, and with water, there is the possibility of life on Mars...
Sources:
The Scientific
Exploration of Mars / Fredric W. Taylor.
Cambridge, UK; New York : Cambridge University Press, 2010.
The Exploration of
Mars/ Wernher Von Braun, Willey Ley, with illustrations by Chesley
Bonestall
New York; Viking Press, 1960
Canals of Mars- The Worlds of David Darling:
The Canals of Mars- ScienceBlogs
Tracing the Canals of Mars: An Astronomer's Obsession by Richard Milner, Astrobiology Magazine- Space.org:
Is Mars Habitable? by Alfred Russel Wallace:
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