Spitzer will revise some of the known planets and their
moons, and comets, asteroids and dust spread throughout the solar
system. The Centre will employ a significant portion of his time studying
circumstellar disks (that surround the stars) of dust and gas found in the
nearby stars and thought to eventually form planetary systems 'extra solar'
(outside our Solar System) .
Objects like the Sun and Moon are too bright and saturate
the sensitive solid state detectors Spitzer. The main objectives planets in the
Solar System are the outer planets, for which at the moment there are no plans
for robotic exploration. Spitzer can only spatially resolve details on
Uranus and Neptune, but the images and spectroscopy will be able to detect differences
in temperature and chemical composition in their atmospheres. Pluto's
diameter is smaller than a pixel Spitzer, and therefore the planet not is
spatially resolved. The observations were limited to the global
caractericacion thermal properties of the icy surface of the planet.
Spitzer will be able to study and characterize the largest
moons of Jupiter, Saturn, Uranus and Neptune. In particular emphasis will be
placed on Titan, the largest natural satellite of Saturn. This intriguing
moon has an atmosphere that will be visited by spacecraft Cassini in
2004, coinciding with the primary mission of Spitzer. The Spitzer
observations will be able to set the global context for the results of the
Cassini and Huygens, helping scientists understand the composition and
large-scale changes in the atmosphere of Titan. Spitzer also carried out
observations of Triton, Neptune's largest moon.
Comets
Comets are very interesting objects for study with Spitzer
because in them is the primitive material has survived from the time of solar
system formation. The observatory will examine comets at large distances from
the Sun and the studies include the structure and composition of cemetery dust
and ice grains and its comparison with dust and ice particles that are similar
in other astronomical environments. In 2003, Comet Encke will pass at
0.2 AU from Spitzer, offering a rare opportunity for the Centre to
conduct an infrared survey which can complement the study from Earth and from
spacecraft CONTOUR.
Asteroids
There are about 11,000 asteroids with known orbits, and four
times as preliminary results on their orbits. However, only 2,000 have
known albinos and diameters, most over 10 km in diameter. It is estimated
that up to one million asteroids of 1 km in size are in the zodiacal belt
between Mars and Jupiter. The large variations found in the reflected
light (visible) in asteroids complicates any attempt to characterize their size
distribution. Therefore, the measures used Spitzer infrared thermal
emission to get a better idea of the asteroids with sizes less than 10 km.
Objects
in the Kuiper Belt
The Kuiper Belt lies beyond the orbit of Neptune and
contains about 100,000 faint and ice cream. This is the source distant
reservoir of comets with short periods and large eccentricities. To date,
astronomers have discovered only a few hundred of these objects. Because of its
weak light, KBOs are difficult to detect through its reflected
light. Spitzer will detect its weak thermal emission and determine their albinos
and their physical properties.
Dust Planets
Interplanetary dust is found throughout the solar system and
is the result of the collision of comets and asteroids. This zodiacal dust
is in the same ecliptic plane in which the planets orbit around the sun this
dust studies are not only intrinsically interesting but are needed to filter
the emission is detected when studying faint objects outside our solar system. A
property of the orbit of Spitzer is that the Centre will cross the dust cloud
that follows the Earth in its orbit around the Sun, providing a unique
opportunity to characterize the structure and evolution of the
dust. Moreover, the study of the influence of large bodies (like planets)
in the morphology of the powder is very important in interpreting the results
of observations of circumstellar disks of nearby stars.
Circumstellar Disks and Extra solar Planets
The Infrared Astronomical Satellite
(English) (IRAS) discovered the presence of dust disks around nearby stars
a few. These circumstellar disks are thought to be a common feature of the
evolution of planetary systems in formation. No telescope alone, either in
operation or planned for the immediate future, have adequate spatial resolution
to directly detect planets around other stars.
Spitzer will be able to detect and characterize
circumstellar disks of nearby stars, providing key information about the
formation of planetary systems 'extra solar'. It is extremely difficult to
detect dust disks visible wavelengths because its light is much weaker than
that of the stars. In the infrared but the difference between the emission
of the star and the disk are reduced. Spitzer will study hundreds of
nearby stars to determine the frequency at which apararecen these discs. Also
use imaging and spectroscopy to characterize the spatial structure and
composition of the disks. These data provide valuable information on the
frequency and nature of other planetary systems.
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