Text Release
« Some 160 visitors, many
from thousands of miles
away, made the trek up Mauna Kea for the dedication ceremony on 28
September,
1979. It was a typical beautiful Hawaiian day as the caravan of close
to 40
four-wheel drive vehicles moved slowly up the dusty and winding road to
the
top, passing through the lunar-like landscape of the mountain
slopes. »
This is how the Press Release of
the dedication ceremony of the Canada France Hawaii Telescope (CFHT)
started
twenty-five years ago as visitors discovered this new facility, the
fruit of a
1974 agreement between Canada (NRC - National Research Council), France
(CNRS, Centre National de la Recherche Scientifique)
and the State of Hawaii (University of Hawaii, UH). The sixth largest
telescope
in the world, 3.6-m in diameter, was inaugurated on what might arguably
be the
best astronomic site of the Northern Hemisphere: the summit of Mauna
Kea, a
4200-m dormant volcano on the Island of Hawai’i.
Through a quarter of a
century of
exemplary collaboration between its three partners, CFHT can be proud
of its
impressive technical and scientific accomplishments. From a
first
glimpse to the dark matter of the universe to the discovery of moons
around
nearby asteroids or objects in the outskirts of the solar system, from
peering
under the fog of Saturn’s moon Titan to watching a stellar storm caused
by a
nearby planet, from discovering tens of moons around the giant planets
of our
solar system to watching a planet orbiting one of the components of a
double star,
from looking at water on Mars to observing a bright quasar through a
gravitational lens, CFHT’s contribution to astronomy is indeed
impressive.
Since its beginning,
CFHT does
not seem to have changed much: its telescope is still housed in the
same
building on the Mauna Kea summit ridge. Under the dome, however, new
instruments of increased complexity have been installed that help CFHT
to stay
competitive; a multi-object spectrograph and an adaptive optics system
have
been especially productive. They are used less frequently these days,
as
similar instruments are available on the 8-m class telescopes.
Although bigger
telescopes are better at collecting light with their larger mirrors,
they do
not offer a very wide field of view. Since its early days, CFHT used
large
photographic plates to cover a field the diameter of two full moons on
the sky.
With twenty years of improvement on the CCDs, these detectors used in
today’s
digital cameras make it possible to pave a large area and cover a field
even
wider than the original photographic plates used in the earlier years.
Wide
field imaging is now one of CFHT’s specialties: with MegaPrime/MegaCam,
a field
of 1 square degree (four full moons) is instantly accessible.
With this 340-MegaPixel, CFHT
initiated an ambitious project: the CFHT Legacy Survey (CFHTLS).
Drawing on
three surveys from the Solar System to the remote universe, it will use
500
nights of telescope time over 5 years. While the first scientific
results from
the CFHTLS should come as soon as 2005, it is already possible to look
at
preliminary images of some of the areas surveyed by the project. The
image
released today for CFHT’s 25th anniversary is the result of tens of
hours spent on one of the fields of the CFHTLS to be used for the
detection of
supernovae and for the study of the universe’s large scale structures.
Two new instruments will
be
available at CFHT within a year. Currently being tested on the sky,
ESPaDOnS
will offer high-resolution spectroscopy over most of the visible
spectrum in a
single image, while providing the polarization of the light received;
this will
give access to the magnetic field of the observed objects. In addition,
WIRCam
will complement MegaCam in the infrared. In spite of a smaller field of
view
(1/10th of MegaCam), it will be one of the largest infrared cameras
in operation on a telescope.
WIRcam is a first for CFHT, as it is built in collaboration with two
institures outside of he CFHT membership: the Korea Astronomical
Observatory and the National Taiwan University Academia Sinica
Institute for Astronomy and Astrophysics.
Nowadays,
many of
the scientific achievements of CHFT come from merging CFHT observations
with data obtained on other telescopes, from another facility on Mauna
Kea to telescopes in Chile or the Hubble Space Telescope.
This synergy between telescopes is also at the core of Ohana, a project
in
which CFHT plays a leading role on the mountain: Ohana would link the
Mauna Kea optical telescopes, transforming them into a single
giant
interferometer.
Not only does CFHT offer
excellent instruments to its communities, it offers exceptional
services to its
users as well. For more than two decades, astronomers had to come to
Hawaii to
gather observations — sometimes coming back empty-handed because of
poor
weather while at the telescope. Now, MegaCam users can stay home: CFHT
is
observing for them. Moreover, CFHT provides them with pre-processed and
calibrated images ready to use for science. At a time when the
scientific
potential of the Observatory is at its highest, the CFHT
users will appreciate even more this service quality as it will be
extended to WIRCam as soon as the camera is operational!
With new instruments and exciting projects, there is no doubt that CFHT
will
stay at the
forefront of astronomy in the coming years!