That the ship was downed by the alignment of celestial bodies is an alluring theory, but it's not, alas, a plausible one.
There was a bit of a buzz last week about Sky & Telescope's cover story for its April 2012 issue, commemorating the 100th anniversary of the sinking of the Titanic, which occurred on April 14, 1912. In the article, two astronomers from Texas State University-San Marcos, along with a senior contributing editor of Sky & Telescope, put forth an intriguing theory about what might have caused the high number of icebergs that made their way into the shipping lanes used by Titanic and other passenger and cargo ships in 1912.
The theory of the Texas astronomers is that a highly unusual confluence of cosmic events might have been an invisible causal factor in the wreck. Specifically, they explain that on January 4, 1912, the Moon passed closer to the Earth than it had in the previous 1,400 years. Not only did that event coincide with an almost full moon, which normally leads to higher tides each month, but it happened the day after the earth reached its annual perihelion, or its closest point to the Sun. The researchers theorize that the increased gravitational pulls of such a close pass of the Moon, at a full moon, when the Earth was at its closest point to the Sun, could have created a record-setting high tide.
How would a high tide lead to a dramatic increase in icebergs in the shipping lanes? The Texas astronomers theorize that perhaps it lifted "grounded" icebergs that had gotten stuck in shallow water on their southward voyage from Greenland and allowed them to continue their journey, causing an unusually high number of icebergs at the 42-degree latitude mark where the Titanic sank, with the loss of 1500 lives.
"Did the Moon Sink the Titanic?" reads the magazine's cover blurb. To be sure, it's a titillating headline and theory, which accounts for some of the wide play it received. In addition, the Titanic was such a terrible tragedy -- half the lives lost to icebergs over a 200-year period were lost that single night -- that it also seems poetically fitting for the calamity to have been caused by a literal lining up of the stars (well, celestial bodies), against astronomical odds. Almost as if the gods themselves had willed the accident to happen. Unfortunately, it appears that the causes of the accident are much more down to Earth.
Truth to tell, I'd never really given much thought before to how all those icebergs got in the Titanic's path in the first place. So I started looking into it.
It turns out that April through June are the high risk months of icebergs in the North Atlantic. As far back as the early 1800s, ship captains would note any sightings of icebergs in their ship's logs on North Atlantic crossings. That data was collected by the U.S. Navy Hydrographic Office and reported in weekly notices to shipping companies. The data was incomplete, to be sure, although it got much better with time and the invention of the wireless radio. But as a result of the reports, a kind of "best practices" advice would be issued to shipping companies about the best routes to follow across the Atlantic to avoid iceberg risks.
In addition, as a result of the Titanic tragedy, the International Ice Patrol was formed in 1913, which sent ships to locate and note the position of icebergs in the North Atlantic (a task made much easier today with airplanes and satellites). And a look at the International Ice Patrol data on how many icebergs end up in potential shipping lanes each year is instructive:
(Murphy, Donald L., 2011. International Ice Patrol's Iceberg Counts 1900-2011. Appendix D to Report of the International Ice Patrol in the North Atlantic, Season of 2011, Bulletin No. 97.)
An average of 500 icebergs a year make it far enough south to be a threat to the shipping lanes, and there were more than 1,000 in 1912. So 1912 was certainly a bad year, in terms of iceberg sightings. But if that spike was caused by a once-in-1400-years cosmic phenomenon, then how do you account for the equally big spike just three years earlier? Or the much bigger spikes in 1929 or 1994, or any number of other years?
Brian Hill, a recently retired ice expert for the Institute of Ocean Technology at the National Research Council of Canada, is perhaps the world's expert on iceberg/ship collisions, having plotted the locations and results of collisions dating back to the beginning of the 1800s. (His listing is amazingly comprehensive, as well as fascinating reading.) So I asked him what he thought about the the 1912 iceberg season.
"1912 was certainly a bad year for sea ice and icebergs," he said, "but not that unusually so. Ice conditions from about 1880 through the early 1920s were generally more severe than we have now. ... 1909 was pretty bad, also. 1899, 1903, 1905 and particularly 1890 all had plentiful bergs stretching down to about the 40th parallel, so the mariners of the time knew perfectly well what could be expected."
Indeed the British Wreck Commissioner's1912 Inquiry report summary on the Titanic sinking noted that icebergs in years past had been seen as far south as the 39th parallel -- and while the Titanic's course put it south of the known area of "field ice," the ship was 100 to 300 miles inside that larger "iceberg threat" area. The Titanic wreck was also "not the farthest south of known collisions [with icebergs]," according to Hill. In fact, Hill's list contains 20 ship/iceberg collisions farther south than the Titanic's position --15 of which happened before 1912, including the Knight Bachelor (photo below), in 1897.
So, 1912, while a bad year in terms of iceberg threats, was not unprecedented, or even unexpected. But what about the tide theory of iceberg movement in general?
According to Dr. Donald Murphy, the oceanographer for the Coast Guard's International Ice Patrol, a difference in tides -- even an unusually high tide -- is unlikely to be "a dominant reason" for an increased number of icebergs moving south. "The spectacular variability we see in iceberg counts," he says, "is due to the complexities of oceanographic currents and meteorological conditions, not the tides." Even a tide a number of feet higher than normal is unlikely to make much of a difference in large iceberg movement, he says, even if it lifts a few icebergs in shallow bays.
Murphy explains that it takes from one to three years for a piece of ice that breaks off the Greenland glaciers to make its way below 48 degrees N latitude, which is where most of the transatlantic shipping occurs. The icebergs float south on the Labrador Current, east of the Grand Banks of Newfoundland, losing mass as they go. In some years, when the weather is colder and floating sea ice is more plentiful, the icebergs are more protected and are more likely to make it further south. So if 1912 was, as Hill says, a "bad year for sea ice" (due to colder weather conditions), that would have protected the icebergs and facilitated a higher number of them making their way into the shipping lanes. (For more information on icebergs, see the Ice Patrol's website.)
The salient feature in that scenario, however, would have been a harsh winter, not an unusual alignment of the planets or the stars. And while Murphy says that the exact reasons why some years favor iceberg movement south and others do not are still "not very well understood," Hill argues that the sinking of the Titanic was anything but an event requiring a unique alignment of the stars.
"Collisions with icebergs were common," he says. "[There were] about 15 in 1884, 30 in 1885, 20 in 1890, 16 in 1897. For over 20 years [before the sinking of the Titanic], the editorials in many of the newspapers and shipping journals were highly critical of ... the incessant demand for ever increasing speed with ships charging across the North Atlantic with undue care for safety in the hazards of fog and the hidden obstacles of derelicts and ice.
"In other words," Hill concluded, "the Titanic disaster was just waiting to happen ... The most shocking thing about it was its inevitability. People knew it would happen sooner or later, but the industry did little about it."