AN ODDITY IN SPACE BAFFLES EXPERTS

Light Deep in the Northern Sky Appears to be Like Nothing Seen Before Now astronomers have an unyielding mystery on their hands, something they have observed and pondered for three years, a point of light deep in the northern sky that appears to be like nothing seen before. 

The mystery object has so far confounded astronomers because they cannot decipher the language of its light. ...astronomers are finding nothing familiar about the light spectrum...  They are beginning to sympathize with archeologists who sought to read Egyptian hieroglyphics without the Rosetta Stone. I've never seen a spectrum anything like this, and I take spectra for a living," said Dr. S. George Djorgovski, an astronomer at the California Institute of Technology who is the leader of the sky survey that detected the mystery object.

http://www.nytimes.com/library/national/science/081799sci-mystery-star.html