The Carnegie Observatories of the Carnegie Institution, and the University
of Arizona, Steward Observatory Mirror Lab, have signed an agreement to
produce the first mirror for the Giant Magellan Telescope (GMT)the first
telescope of the next-generation of extremely large ground-based
telescopes (ELT) to begin mirror production. The telescope primary mirror
will have a diameter of 83 feet (25.4 meters) with more than 4.5 times the
collecting area of any current optical telescope.

“This agreement is historic for the future of astronomy,” stated Dr.
Richard Meserve, president of the Carnegie Institution. “It is the first
of many milestones that we and our partners look forward to–both in
constructing an enormous ground-based telescope and in the scientific
discoveries that will result. Everyone in the eight-member GMT consortium
is extremely excited by this step,” he added. The consortium includes the
Carnegie Observatories, Harvard University, Smithsonian Astrophysical
Observatory, University of Arizona, University of Michigan, Massachusetts
Institute of Technology, University of Texas at Austin, and Texas A&M

The GMT is slated for completion in 2016 at a site in Northern Chile.
Viewing conditions in Chile, such as at Carnegie’s Las Campanas
Observatory, are some of the best in the world. The GMT will have ten
times the resolution of the Hubble Space Telescope. With its powerful
resolution and enormous collecting area, the GMT will be able to probe the
secrets of planets that have formed around other stars in the Milky Way,
peer back in time toward the Big Bang with unprecedented clarity, delve
into the nature of dark matter and dark energy, and explore the formation
of black holes–the most important questions in astronomy today.

“The Giant Magellan Telescope will allow an unprecedented view of
extrasolar planets as well as a window out to the largest scales and back
to the earliest moments of the universe. We plan to complete the GMT so
that it will work in tandem with the future generation of planned ground-
and space-based telescopes,” stated Dr. Wendy Freedman, director of the
Carnegie Observatories. “The real distinction of the GMT, however, is that
it is building on a heritage of successful technology developed for the
twin 6.5-meter Magellan telescopes at Las Campanas. Their performance has
far exceeded our expectations. The Magellan telescopes have proven to be
the best natural imaging telescopes on the ground, due in large part to
the genius of its Project Scientist, Carnegie Observatories’ Stephen
Shectman, and Roger Angel and his team at the Steward Mirror Lab,” she

The mirrors for the GMT will be made using the existing infrastructure at
Steward that made the 6.5-meter Magellan mirrors and the 8.4-meter Large
Binocular Telescope mirrors on Mt. Graham. The new telescope will be
composed of seven, 8.4-meter primary mirrors, arranged in a floral
pattern. One spare off-axis mirror will also be made. Seven of the eight
mirrors will be off-axis and require new techniques in casting and
polishing. The first off-axis mirror will be cast this coming summer
(2005) to address the new challenges. “The upcoming decade promises to be
a very exciting one for astronomy. The National Academy of Sciences
Astronomy and Astrophysics Survey Committee Report (2001) ranked the
science for extremely large telescopes as the highest priority for
ground-based optical astronomy,” said Jeremy Mould, Director of the
National Optical Astronomy Observatory.

Site testing at the Las Campanas Observatory is also underway along with
many other aspects of the project. Detailed information about the design
of the GMT and the science that it will perform is located

Image at


This schematic shows the Giant Magellan Telescope (GMT) next to one of the
existing 6.5-meter Magellan telescopes. The GMT primary mirror will have a
diameter of 83 feet (25.4 meters) with more than 4.5 times the collecting
area of any current optical telescope.

The Carnegie Observatories was founded by George Ellery Hale in 1904.
Located in Pasadena, California, the Observatories operates telescopes on
Cerro Las Campanas, Chile. The Carnegie Institution
( has been a pioneering force in basic
scientific research since 1902. It is a private, nonprofit organization
with six research departments throughout the U.S. Carnegie scientists are
leaders in plant biology, developmental biology, astronomy, materials
science, global ecology, and Earth and planetary science.