WP 1300 Optics UV/IR studies

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WP 1300Optics UV/IR studies
Speaker Carmelo Arcidiacono INAF
PD Coordinator Roberto Ragazzoni INAF - PD
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UltraViolet Optics and InfraRed Work Package

• Formal and informal contributions coming from
  collaborators in throughout Italian Universities
  and Observatories
• Five themes
• WP 1310 Solar Observations
• F. Berrilli, Roma Univ. Tor Vergata
• WP 1320 Solar System Minor Bodies Observations
• M. Di Martino, A. Cellino INAF OA Torino
• WP 1330 Wide FoV Telescope
• Mid Infrared Telescope
• Interferometry for extremely high resolution

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WP1310 Sun ObservationScientific drivers
descriptionis demanded to the talk
 High Priority and Heavier Payloads   1600 TIGRE
M. Feroci (INAF) 1615 PIM C. Labanti (INAF)
1630 High Resolution Solar Imaging from the
Moon F. Berrilli (INAF, Tor Vergata Univ.) 1645
Spectral Distortions of CMB C. Burigana
(INAF) 1700-1730 General Discussion and
Conclusions  
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WP 1310 Sun Observations

• A 1 to 2 m Gregorian Diffraction limited
  UltraViolet telescope for Solar Observations.
• Aiming to explore magnetic tubes fluxes, their
  evolution and interaction with other Solar
  features.
• Spectrum-polarimetry essential
• High Priority

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WP 1310 Sun ObservationsSite

• Polar Zones
• Crater Edge or rim

Continous Sun Observation High Visibilty from
Earth for communications
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WP1310 Sun ObservationPayload Technical
Specifications

• Gregorian Optical Design, Diameter 1.5m,25m focal
  length
• Field of View 100x100 arcsec
• Bandwidth 300-600 nm extended to 600-1600 nm
• Angular Resolution Diffraction-limited single
  dish 0.1arcsec resolution is needed in order to
  be competitive with other space missions at low
  orbit or in the Lagrangian Points.
• Spectral Resolution FWHM of the
  spectro-polarimetric 500pm Such as resolution
  could be obtained through the combination of a
  narrow band filter (3-5Å) and a Fabry-Perot
  interferometer
• Temporal Resolution
• 90sec are necessary to sample the photosphere
  and chromosphere spectral line in his different
  polarization states and to characterize the
  related dynamics
• Heliosismology studies 30-50s temporal sampling
• Imaging 5 sec
• Weight estimation 350kg

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WP1310 Sun ObservationCompetitors or Precursors?

• Large diameter size and high temporal resolution
  allow beating the forthcoming free flyers
  competitors (2007-2027)
• SOLAR-B SOT (Solar Optical Telescope)
• SDO HMI (Helioseismic and Magnetic Imager)
• SOLAR ORBITER VIM (Visual Imager Magnetograph)
• A suite of solar instruments
• Imaging
• Spectroscopy
• Polarimetry

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WP 1320 Solar System Minor Bodies

• About 2 m Diffraction limited optical telescope
• Characterization of Inner Earth Asteroids (IEA),
  direct measurement of asteroid sizes, spin and
  shape properties, characterization of Kreuz
  family comets.
• Medium Priority

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• Moon Advantages
• Diffraction-limited images
• Observations of Regions at low solar elongations
• Long baseline Earth - Moon

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• Why to make hi-res observations of asteroids?
• To measure their angular sizes
• To reconstruct their 3-D shapes
• To find binary systems
• To find surface heterogeneity (albedo spots)
• To investigate light scattering properties
• including limb darkening

Speckle interferometry observations at TNG
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4 Vesta (HST)
Resolving the apparent disks of asteroids leads
to reconstruct the 3-D shape of the objects.
Knowledge of the volume is then used to derive
average density when the mass is known (from
gravitational perturbations, or the presence of a
satellite)
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Binary Asteroids At present, about 24 near-Earth
and 36 Main Belt asteroids are known or suspected
to be binaries Binaries are extremely important
because they allow us to derive asteroid masses,
and put constraints on the collisional evolution
of the population.
90 Antiope
45 Eugenia
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Asteroid families close to Earth orbit

• Atens
• Average orbit lt 1 AU
• Perihelia lt 1 AU, Afehelia gt 1 AU
• Apollo
• Average orbit gt 1 AU
• Perihelia lt 1 AU, Afhelia gt 1 AU
• Amors
• Orbit 1.017 AU lt distance lt 1.17

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Solar elongations vs. Earth distance
Aten objects lt 1, Q gt 0.983 AU
Orbital evolution of 21 Atens (821 yrs). Plot of
Solar elongation vs. Earth distance every 40 days.
Large dots Mv lt 16 Medium dots 16 lt Mv lt
18 Small dots 18 lt Mv lt 20
(integrations made by Boattini and Carusi)
In addition to Atens, a new class of objects,
with orbits completely inside Earths orbit, has
been found to exist necessarily, through
numerical integrations of NEO orbits. These
objects have been called IEOs (objets Interior to
Earths Orbit). Only a very few IEOs have been
so far discovered, due to the difficulty of
observing IEOs from ground, since they never are
visible at large solar elongations. A Moon-based
telescope would not be affected by such
limitations.
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Limits of current ground-based NEO surveys
Numerical simulations indicate that currently
active ground-based NEO surveys aimed at
discovering Potentially Hazardous objects can be
unable to discover in advance all the possible
impactors larger than 1 km, even after 100 years
of observations. Numerical simulations indicate
that most impactors are visible in advance only
by observing systematically the regions of the
sky within 90o from the Sun, whereas surveys
hardly observe beyond this limit.
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Observations of Sun-grazing comets Due to the
lack of atmosphere, a Moon-based telescope,
equipped with a solar coronograph, would be very
efficient in observing Sun-grazing comets.
Sun-razing comet observed by the SOHO solar
observatory
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A Moon-based telescope would nicely complement
future large sky surveys, since it would permit
to determine the distance of newly-discovered
objects by means of measurements of the diurnal
parallax (having the Earth-Moon distance as the
baseline). This would be very useful for
NEO-discovery surveys.
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Parallax measurements would be also extremely
useful to constrain the orbits of Trans-Neptunian
objects. By observing an object as seen in
quadrature from two opposite locations along the
Moons orbit around the Earth, it should be
possible to measure the parallax, and to derive
the distance of the object. This could be done in
principle also from the Earths ground, using the
Earths orbit diameter as the baseline and
observing the same object after six months. This
has never be done so far due to practical
problems (telescope scheduling, etc.). A
Moon-based telescope could do the same using the
Moons orbit as a baseline and observing the same
object after (about) 15 days, only. Such parallax
measurements would improve very much the
computation of TNOs, that are poorly known due to
their very slow motion on the sky sphere.
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WP1320 Solar System Bodies ObservationPayload
Technical Specifications

• Diameter 2m,
• Focal length gt3m
• Field of View 30x30 arcsec
• Bandwidth 500-800 nm extended to 300-1000 nm
• Angular Resolution Diffraction-limited single
  dish 0.05arcsec
• Spectral Resolution Wide Filters
• Weight estimation 500kg

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WP 1330 Wide Field Telescope

• 4m to 8m Diffraction limited telescope
• Survey for detection
• Micro-lensing,
• search for planetary systems through photometric
  eclipses,
• study of optical transient due to Gamma Ray
  Bursts
• Search for extragalactic clusters.
• Search for extragalactic Supernovae.
• Large Spectral range 0.3-2.2 micron
• Field of View required (2x2-5x5 degrees)
• Site Polar Zones
• In a crater to be shielded by Solar radiation

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WP1330 Wide FieldPayload Technical Specifications

• Diameter 4m,
• Focal length 6m
• Field of View 2x2 deg / 5x5 deg
• Bandwidth 0.3 -2.2 micron
• Angular Resolution Diffraction-limited single
  dish 0.02arcsec
• Spectral Resolution Wide Filters
• Weight estimation gt1000kg

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Mid Infrared facility

• Competitors/Precursors
• A mid infrared telescope to be placed on the Moon
  represent the natural update of the James Webb
  Space Telescope (JWST)
• A thermal InfraRed telescope for Galactic
  Astronomy and Cosmology
• Scientific Objectives
• Stellar formation in low-z Universe,
  ultra-luminous IR galaxies and far-z isotopical
  abundances, spectroscopy JWST very high
  redshift galaxy
• High Resolution Spectroscopy necessary
• Survey towards ecliptical poles to minimize
  thermal background emission (Zodiacal Light)
• Site Polar Zones
• In a crater to be shielded by Solar radiation

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Mid Infrared facility

• Unique advantage with respect to free space
• gravity
• Very long integration time
• Liquid Mirror technology already proven on
  Earth (6meter) will allow to build huge facility
  on the Moon
• Zenithal telescope
• Anionic Liquid Tlt150K

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Mid Infrared facility Payload Technical
Specifications

• Diameter 20m
• Focal length 30-50m
• Field of View 15x15
• Bandwidth Thermal Infrared
• Angular Resolution Diffraction-limited single
  dish 0.01arcsec
• Technology liquid mirror
• Spectral Resolution high
• Weight estimation 1000kg only the mirror..

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Interferometry

• Interferometry uses the unique ability of the
  Moon surface to provide extremely long, stable
  and remotely re-deployable baselines
• A few to several 1 to 2m classes telescopes and
  more than one recombining focal stations
• Very high spatial resolution
• Compact objects studies (Galactic center BHs, BHs
  in nearby Galaxies) by differential astrometry
• Site Big (up to several km) free surface

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Priorities List

• Priority 1 Imaging-Spectro-Polarimetry Solar
  Observation
• Priority 2 Minor Bodies Solar System Observation
• Priority 3 Wide Field, Mid Infrared telescope
  and interferometry

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Can be a precursor mission planned?

• Spectro-Polarimetry Solar Observation
• Already planned Free Flyers missions
• Minor Bodies Solar System Observations
• 0.5-1m robotic telescope on the Moon surface can
  anticipate a fraction of the big brother
  results
• Wide Field telescope
• Difficult on the Moon, LSST on Earth
• Mid Infrared telescope
• JWST
• Interferometry
• Concept can be proven on a small array of
  0.2-0.5m telescopes on short fixed baseline
  (30-50 m to give top results on very bright
  targets)

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WP1300 conclusions

• Sun and Solar System observations could open the
  UV/optical/IR window from the Moon with leading
  science and reasonable projects
• The other proposed cases could represent the
  first step toward a large facility, larger than
  any other expected on Earth and to be lunched in
  space (E-ELT, with 42m diameter, and JWST, a
  6.5m), will satisfy most of any possible
  scientific rationale which can be conceived