The NOAO Gemini Science Center (NGSC)
is the gateway for the U.S. astronomical community to the international
Gemini Observatory Project.
The Gemini project is a multi-national collaboration to provide twin 8 meter
astronomical telescopes utilizing new technology to produce
some of the sharpest views of the universe ever. One telescope is located
on Hawai'i's Mauna Kea (Gemini North) and the other on Cerro Pachón
in central Chile (Gemini South). Together they will provide complete
unobstructed coverage of both the northern and southern skies.
Astronomers will use Gemini to probe the cosmos,
from planets circling other stars, to the heart of our own galaxy,
to the formation of the first galaxies in the universe.
The United States'
Gateway to Gemini
is the NOAO Gemini Science Center,
a division of NOAO based in Tucson, Arizona.
The international project is funded under a cooperative agreement with
The U.S. National Science Foundation.
The NSF serves as the executive agency for the international partnership.
The Gemini telescopes are the largest, most advanced optical/
telescopes available to astronomers in the U.S.A. regardless
of institutional affiliation.
The Gemini Observatory provides the astronomical communities in each partner
country with state-of-the-art astronomical facilities that will allocate
observing time in proportion to each country's contribution.
U.S. astronomers receive 42% of the observing time on Gemini.
In addition to financial support, each country contributes scientific and
technical resources. Significant support of the construction, operation, and
instruments has been provided by the U.S. National Science Foundation (NSF)
as well as several U.S. universities, private industry, and NOAO.
National Research Agencies that Form the Gemini Partnership
Gemini Project Status
The Gemini North Telescope on Mauna Kea is nearing completion,
and science observations
began during the summer, 2000, with two visiting instruments, an adaptive
optics imager on loan from the University of Hawai'i and a 10-20 micron
imager/spectrometer from the University of Florida. The first facility
instrument, a Near-Infrared Imager (NIRI) built at the University of
Hawai'i, is being commissioned at Gemini North, and a second facility
instrument, an optical spectrograph, is expected soon.
The Gemini South Telescope has seen first light at its site on Cerro
Pachon in northern Chile. Science observations are expected to begin
mid-year in 2001.
Some especially intriguing areas of our universe are those hidden from view,
at visible wavelengths, by clouds of gas and dust. Such areas include those
where stars and planets form as well as cores of galaxies where black holes
might reside. The infrared part of the electromagnetic spectrum encompasses
the wavelengths just beyond and longer than visible wavelengths.
These longer wavelengths penetrate the clouds of gas and dust
so one can see details otherwise hidden from view. Gemini's ability will
take us to the core of our own and other galaxies to provide new insights
into the violent events that dwell in these areas.
Gemini's huge mirrors will collect more of the often sparse light from space
thus improving our window to the universe. With its new technology,
Gemini should lead the way for a new generation of large telescopes.
In the past, large mirrors were limited by the fact
that they had to be excessively thick in order to keep their shape.
Active optics enable Gemini's 8.1 meter primary mirror to be relatively thin
while maintaining its precise shape. Mounted behind the mirror are 120
"actuators" that constantly nudge the mirror back into perfect form.
These adjustments are typically only about 1/1,000 the thickness
of a human hair and are enough to keep starlight precisely focused
so astronomers can study the universe.
Turbulence in our atmosphere distorts light, causing stars to twinkle.
Large telescopes magnify the distortion so that, untreated, a point
of starlight looks more like a blurry blob. "Wind shake" and thermal effects
add to the problem. On Gemini a relatively new technology
called Adaptive Optics (AO) will be used to straighten the light out again.
The AO system takes a sample of light, determines how the atmosphere bent it,
and makes very small adjustments to a deformable mirror which counteracts
the distortions caused by the atmosphere. The secondary mirror at the top
of the telescope also can be adjusted up to a hundred times per second
to help compensate.
AO systems work best with longer wavelengths so Gemini's
will yield the most dramatic results. Gemini should produce the sharpest
images yet of the infrared sky and dramatically improve many other types
of observations as well.
Telescope commands and astronomical data are transmitted electronically
between the northern and southern telescopes and their control centers
in Hilo, Hawaii and La Serena, Chile. Such remote operations allow
scientists and engineers to conduct their precision work
in the more hospitable environment at sea-level.
The partners are developing a suite of instruments to complement
these high-tech telescopes. With superb optical and infrared capabilities,
we will probe areas of our universe with more clarity than ever before.
Ultra-sensitive detectors and the latest optical and computer technology
will make these two of the best equipped telescopes on our planet.