There's a great feature article in last week's issue of Science that describes a 'race for the heavens' between the University of Arizona and partner's $700 million Giant Magellan Telescope (GMT, right) and the Univ. of Calif.'s $1 billion Thirty Meter Telescope (TMT). Neither proposed instrument "has come close to securing the total funding it needs."
The story contrasts the personalities and visions of the leading advocates for both instruments, Roger Angel at UA and Jerry Nelson at UC.
The GMT would link 7 monolithic mirrors, each 8.4 meters across. Angel's lab produced the two 8.4 meter mirrors used in the Large Binocular Telescope that went into operation on Mt. Graham in Arizona in 2007.
The article reports that it's too late for the two projects to be combined. Each is at different stages in fund raising, design, and implemtation, so it's too early to tell which, if either is going to be built. Science posted a podcast interview at http://www.sciencemag.org/cgi/content/full/326/5952/512/DC1