Unexplained Mysteries Entering 2012

Though a variety of old and new mysteries were solved in 2011, many more mysteries remain unexplained as we begin 2012. Here are five.
Mysterious Bee Deaths
 
The collapse of bee colonies has worried biologists for years. Since 2006, between 20 percent and 40 percent of the bee colonies in the United States have suffered massive die-outs called "colony collapse." Many explanations have been proposed, ranging from pesticides to cell phone signals to climate change. As Discovery's Liz Day noted, "scientists are fingering their latest culprit in the dramatic disappearance of honeybees: a fungus and virus team... The virus affects bees' abdomens, often turning their tissues a purplish tone. The fungus, which also targets the bees' guts, is called Nosema ceranae. Combined, it seems the duo prevent bees from getting enough nutrition."
Though scientists have some important clues, a conclusive answer to the mystery remains elusive. Correlation does not imply causation, and just because all of the collapsed colonies had the virus and the gut fungus does not mean that the combination necessarily caused the bees to die; the presence of either one alone does not lead to colony collapse. How these cause colony collapse -- if in fact they do -- remains unknown.
Faster Than Light Experiments
 
In September 174 physicists at the CERN laboratory announced that they had shot particles between Switzerland and Italy at really high speeds. After three years of experiments and analysis, the team concluded that the neutrinos they fired arrived in Italy at one 17-millionth of a second earlier than expected. Now, one 17-millionth of a second doesn't seem like a big deal; the issue was that, if confirmed, that speed would be faster than light -- which definitely is a big deal.
The experiment was run again in November, and to the consternation of many (and the delight of some) they got the same result. Further experiments are necessary to know whether there was a miscalculation somewhere, or whether Einstein’s theory of relativity has a big hole in it. Perhaps 2012 will reveal the answer.
The Impact of the BP Oil Spill
 
What will be the impact of the 2010 BP oil spill that poured almost 5 million barrels into the Gulf of Mexico? Scientists still don't know the answer. The initial predictions, from both the public and scientists, were dire: the ecosystem would be destroyed for the foreseeable future, devastating not only the wildlife but the local economy and tourism. Time magazine revisited the Gulf states in 2011, concluding that "nearly a year after the spill began, it seems clear that the worst-case scenario never came true. It's not that the oil spill had no lasting effects -- far from it -- but the ecological doomsday many predicted clearly hasn't taken place.... the damage does seem so far to have been less than feared.
Scientists with the National Oceanic and Atmospheric Administration estimated last August that much of the oil had remained in the Gulf, where it had dispersed or dissolved. Many environmentalists attacked the report for underplaying the threat of large underwater oil plumes still active in the Gulf, yet later independent scientific studies indeed found that oil had "largely disappeared from the water." Still, oil sludge continues to be found on beaches and the ocean floor. Amid the dueling reports and accusations of bias one thing is clear: as we enter 2012 the long-term effects from the largest oil spill in U.S. history remain unknown.
Extraterrestrial Life on Earth-Like Planets? 
 
Are we alone in the universe? It's an age-old question that remains unexplained despite advances and discoveries in the past few years, and the idea got tremendous support in 2011. In January it was announced that the Kepler Space Telescope had found the first hard evidence of a rocky planet beyond the solar system: Kepler-10b, an exoplanet about one and a half times the size of Earth.
Though its surface is thought to be too hot to sustain life as we know it, astronomers suspect that it could have sustained life at some point in the past. That discovery came only a few months after scientists reported finding a planet called Gliese 581g, which is at just the right size and location to be hospitable for life. Then in December came the announcement that a planet with the unremarkable moniker Kepler 22b had been found: "A planet about twice the size of Earth has been confirmed to exist right in the middle of the 'habitable zone' around its star, which is much like our own... this is the first time such a life-friendly alien planet has been confirmed."
Each year the scientific community finds more and more potential Earth-like bodies, yet proof of extraterrestrial life remains elusive. When it comes to knowing whether there's life elsewhere in the universe, the question remains an unsolved mystery.