Max Planck Institute for Astronomy - Annual Report 2005

V People and Events
V.1 First Light for the Large Binocular Telescope
On October 12 th , 2005, the first astronomical pictures
were taken with the Large Binocular Telescope (LBT).
This »First Light« was an important milestone in the
commissioning of the world’s largest single telescope.
Under the coordination of the MPIA, five German institutes
are LBT partners contributing to the development of
this unique telescope. The LBT will open up completely
new opportunities for extrasolar planet research and the
investigation of the distant Universe.
Located on the 3190 m high Mount Graham, Arizona,
the LBT is one of the outstanding scientific-technical
projects of modern astronomical research. The telescope
is equipped with two primary mirrors of 8.4 m diameter
each that are fixed on one common mount and thus can
be pointed simultaneously to distant celestial objects.
By combining the light paths of both mirrors, the LBT
gathers as much light as a telescope of 11.8 m aperture,
thus surpassing the Hubble Space Telescope's light gathering
power by a factor of 24.
Even more important, however, is the fact that the
LBT should be able to achieve the resolving power
equivalent to a single 22.8 m telescope. This ambitious
goal can only be accomplished by using an adaptive op-
tics system combined with Fizeau interferometry. Some
components of the LBT necessary for this technique are
still under development. These include the extremely
thin adaptive secondary mirrors and the linc-nirvana
instrument which will provide the interferometric combination
of the two light beams. MPIA is the PI Institute
for the building and development of this central LBT
component (see Chapter IV.4).
The go-ahead for first light was given when the first
primary mirror was mounted into the telescope structure.
On October 12 th , 2005, the telescope was pointed towards
the spiral galaxy NGC 891, which lies at a distance of
24 million light years in the constellation of Andromeda.
The first high-quality images were taken with the Large
Binocular Camera (LBC) in the telescope's primary
focus through a blue filter (a camera version for the red
spectral range is under construction). The LBC, with its
core of four CCD detectors of 2046 3 4608 pixels each,
has been provided by the Italian partners of the project.
Several exposures with a total of five minutes exposure
time were combined into a single image with
Fig. V.1.1: Still one-eyed: The LBT on Mount Graham.
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