In September 2008, scientists fired its first beams, however, the celebrations were soon replaced by disappointment when an electric fault caused serious damage to one of the sectors of the circular track.  The accelerator's work was set back and repairs began.  The repairs were further delayed by the onset of winter.

Now, the repairs are complete, and last week scientists fired the accelerator up cautiously for a second time.  The accomplishment was the latest in a series of baby steps that occurred over the last two months.  On October 8, the accelerator completed its chilling cycle, using its vacuum chamber to reach 1.9 degrees Kelvin or about -271 degrees Celsius.

Next, particles were injected on October 23.  Then on November 7, beams were steered through three octants of the machine.  Finally, on November 18, beams were fully circulated around the LHC, an important milestone.

CERN Director General Rolf Heuer states, "It’s great to see beam circulating in the LHC again.  We’ve still got some way to go before physics can begin, but with this milestone we’re well on the way.  It’s been a herculean effort to get to where we are today.  I’d like to thank all those who have taken part, from CERN and from our partner institutions around the world."

This week another integral step will be carried out -- completing collisions to provide calibration data.  This landmark step will mark the accelerator's first collisions.  It will be followed by a slow ramp-up to full-strength collisions, at an energy of 7 TeV (3.5 TeV per beam).

The full-strength collisions are feared by some in the public who worry that they may produce out of control mini-blackholes or strangelets, theoretical particles.  Theoretical physicists insist that after extensive review they have found the risk of such dangers to be virtually nonexistent, and the collisions to be safe. 

Despite these reassurances, the LHC has provoked a diverse response, including in literature and the media.  It is centrally featured in the novel FlashForward by Robert J. Sawyer, and in the television series based on the work.  It is also a major plot device in the Dan Brown book Angels & Demons, in which the Vatican's enemies try to use antimatter created by the accelerator as a weapon of mass destruction.

CERN is set to hold a press conference on Monday afternoon which should hold more juicy details about the accelerator's restart.  The LHC's primary mission is to find the Higgs boson, a theorized, but never observed particle.  Many other secrets of our universe's physical properties should be unraveled along the way.