Two new
instruments will give the Large Binocular Telescope a set of sharper eyes
capable of studying planets outside our solar system in greater detail.
A pair of new-generation instruments to be mounted on the world's
largest optical telescope, the Large Binocular Telescope, or LBT, located on top
of Mount Graham in Arizona, will turn the telescope into a formidable hunter of
extrasolar planets. Named SHARK (short for System
for coronagraphy with High order Adaptive optics from R to K band), the instruments will enable astronomers to obtain direct
images of exoplanets, including very faint ones, by more effectively blocking
the otherwise overpowering light from their host stars.
INAF, the Italian National Institute for Astrophysics, is leading the
international consortium that will build the instruments and will also manage
their scientific use.
SHARK recently has received the official green light from the LBT board,
and the two instruments are expected to become fully operational by the end of
2019. SHARK consists of a pair of instruments working synergistically in
visible light (SHARK-VIS) and in the near infrared (SHARK-NIR). These will be
operated in parallel, taking advantage of the two big 8.4-meter mirrors of the
LBT, thus making it the first telescope in the world capable of observing
exoplanets simultaneously over such a wide range of wavelengths.
The main problem exoplanet hunters face when studying exoplanets is the
extreme contrast between the planets' faintness in comparison to their host
stars' light, explains Christian Veillet, director of the Large Binocular
Telescope, which is managed by the University of Arizona.
To be able to study candidates for potentially Earth-like planets, for
example, astronomers need more sophisticated instruments to tease out the
signal from the noise.
The "SHARKs" will take full advantage of the outstanding
adaptive optics system mounted on the LBT, which was also developed by INAF.
This system corrects in real time the image distortions induced by the
atmospheric turbulence to deliver final frames that are characterized by a
sharpness and quality of detail better than those obtainable with the Hubble
Space Telescope.
"LBT’s Adaptive Optics is currently undergoing a makeover offering
even better performance, which will be fully utilized by SHARK to bring the LBT
to the forefront of what is possible in this arena," Veillet says.
"We are preparing the path to doing unprecedented science on the next generation
of telescopes, such as the Giant Magellan Telescope, an LBT on steroids with
seven 8.4-meter mirrors on the same mount instead of two."
"With SHARK, we will observe exoplanets at unprecedented angular
resolution and contrast, so that we will be able to go closer to their host
stars than what has been achieved up to now with direct imaging," says
Valentina D’Orazi of the INAF-Osservatorio Astronomico di Padova, instrument
scientist for SHARK-NIR. "This will be possible thanks to the use of
coronagraphy, which blocks out the light from the central star and highly
improves the contrast in the region around the source, thus allowing us to
detect the planetary objects we want to study, which otherwise would remain
hidden in the star light.”
 |
| SHARK-NIR |
"With this great combination,
we will finally be able to reveal many exoplanets around stars in our galactic
neighborhood and better characterize their properties, by also using images in
optical light taken for the first time in the northern hemisphere," adds
Fernando Pedichini of the INAF-Osservatorio Astronomico di Roma and principal
investigator of SHARK-VIS.
 |
| SHARK-VIS |
With SHARK, it will be possible to directly image gaseous giants in the
outer regions of exoplanetary systems, thus obtaining pieces of information
about the architecture of such systems that are complementary to those provided
by techniques purely focused on detection. Such techniques include observing
the gravitational tug unseen planets exert on their host star, or the minuscule
dip in a star's brightness when a planet passes in front of it.
"These observations are key to understanding the formation
mechanisms of planetary systems," says Simone Antoniucci of the INAF-Osservatorio
Astronomico di Roma, instrument scientist of SHARK-VIS. "Moreover, one of
the unique features of SHARK will be the capability to directly observe the
formation process of giant planets around very young stars."
"Thanks to the outstanding sensitivity of the LBT adaptive optics
system, SHARK-NIR, used in parallel with SHARK-VIS and the LBTI LMIRCAM
instrument, will allow us to study not only exoplanets, but also astrophysical
phenomena," says Jacopo Farinato, astronomer at the INAF-Osservatorio
Astronomico di Padova and principal investigator of SHARK-NIR. "For
instance, we will be able to study with formidable accuracy disks and jets of
young stars, gas envelopes around evolved stars, asteroids and minor bodies of
the solar system and even the brightest extragalactic sources such as active
galactic nuclei."
"While these two SHARKs are built as instruments to be operated by the
teams who built them, they will be open to the whole LBT community,"
Veillet adds. "Both teams have garnered an impressive scientific
collaboration, covering the wide range of potential scientific programs as well
as the diverse partnership on which LBT is built."
 |
| Each SHARK will be installed on one side of the LBT Interferometer (LBTI), the green structure seen in the middle of the picture between the two main mirrors of LBT. |
The SHARK consortium is led by INAF, and the partners for the NIR
channel are the Steward Observatory in Tucson (University of Arizona), the Max
Planck institute of Heidelberg (Germany) and the Institut de Planétologie et
d’Astrophysique of Grenoble. The Italian institutes involved in the instrument
construction are the Observatories of Padova, Roma, Arcetri, Milano, Trieste
and the Physics and Astronomy department of the University of Padova.
The Large Binocular Telescope (LBT) is an international collaboration of
the University of Arizona, Italy's National Institute for Astrophysics (INAF),
Germany's LBT Beteiligungsgesellschaft, The Ohio State University, the
Tucson–based Research Corporation representing the University of Minnesota, the
University of Virginia, and the University of Notre Dame. INAF contributes 25 percent of the LBT costs
(construction and management) and owns one fourth of the telescope and of the
same share of observing time.
Contact Information
At INAF, Italy:
Marco Galliani Chief Press Officer - INAF (Italian National Institute for Astrophysics)
office phone +39 06 355 33 390 mobile +39 335 17 78 428 marco.galliani@inaf.it
At LBTO (Tucson, AZ)
Christian Veillet - director@lbto.org - 1 (520) 349 4576
The INAF Press Release (in Italian) is here.
The INAF Press Release (in Italian) is here.
