Hi my friends: A VUELO DE UN QUINDE EL BLOG., We have received of the NASA, the information about the evidences of the shocks of meteorites against the rings of the planet Saturn...these photographies have been caught ..by NASA's Cassini spacecraft,
between 2009 and 2012...
Blame it on the Rain (from Saturn's Rings)
04.10.13
This artist's concept illustrates how charged water particles flow into
the Saturnian atmosphere from the planet's rings, causing a reduction in
atmospheric brightness. Image credit: NASA/JPL-Caltech/Space Science
Institute/University of Leicester
› Full image and caption
A new study tracks the "rain" of charged water particles into the
atmosphere of Saturn and finds there is more of it and it falls across
larger areas of the planet than previously thought. The study, whose
observations were funded by NASA and whose analysis was led by the
University of Leicester, England, reveals that the rain influences the
composition and temperature structure of parts of Saturn's upper
atmosphere. The paper appears in this week's issue of the journal
Nature.
“Saturn is the first planet to show significant interaction between its
atmosphere and ring system," said James O’Donoghue, the paper's lead
author and a postgraduate researcher at Leicester. “The main effect of
ring rain is that it acts to 'quench' the ionosphere of Saturn. In other
words, this rain severely reduces the electron densities in regions in
which it falls."
O’Donoghue explains that the ring's effect on electron densities is
important because it explains why, for many decades, observations have
shown those densities to be unusually low at certain latitudes on
Saturn. The study also helps scientists better understand the origin and
evolution of Saturn's ring system and changes in the planet's
atmosphere.
"It turns out that a major driver of Saturn's ionospheric environment
and climate across vast reaches of the planet are ring particles located
some 36,000 miles [60,000 kilometers] overhead," said Kevin Baines, a
co-author on the paper, based at NASA's Jet Propulsion Laboratory,
Pasadena, Calif. "The ring particles affect both what species of
particles are in this part of the atmosphere and where it is warm or
cool."
In the early 1980s, images from NASA's Voyager spacecraft showed two to
three dark bands on Saturn, and scientists theorized that water could
have been showering down into those bands from the rings. Those bands
were not seen again until this team observed the planet in near-infrared
wavelengths with the W.M Keck Observatory on Mauna Kea, in Hawaii, in
April 2011. The effect was difficult to discern because it involves
looking for a subtle emission from bright parts of Saturn. It required
an instrument like that on Keck, which can split up a large range of
light.
The ring rain's effect occurs in Saturn's ionosphere, where charged
particles are produced when the otherwise neutral atmosphere is exposed
to a flow of energetic particles or solar radiation. When the scientists
tracked the pattern of emissions of a particular hydrogen ion with
three protons (triatomic hydrogen), they expected to see a uniform
planet-wide infrared glow. What they observed instead was a series of
light and dark bands – with areas of reduced emission corresponding to
water-dense portions of Saturn’s rings and areas of high emission
corresponding to gaps in the rings.
They surmised that charged water particles from the planet’s rings were
being drawn towards the planet along Saturn's magnetic field lines and
were neutralizing the glowing triatomic hydrogen ions. This leaves large
“shadows” in what would otherwise be a planet-wide infrared glow. These
shadows cover some 30 to 43 percent of the planet's upper atmosphere
surface from around 25 to 55 degrees latitude. This is a significantly
larger area than suggested by images from NASA’s Voyager mission.
Both Earth and Jupiter have an equatorial region that glows very
uniformly. Scientists expected this pattern at Saturn, too, but they
instead saw dramatic differences at different latitudes.
"Where Jupiter is glowing evenly across its equatorial regions, Saturn
has dark bands where the water is falling in, darkening the ionosphere,"
said Tom Stallard, a paper co-author at Leicester. "We're now also
trying to investigate these features with an instrument on NASA's
Cassini spacecraft. If we're successful, Cassini may allow us to view in
more detail the way that water is removing ionized particles, such as
any changes in the altitude or effects that come with the time of day."
Keck observing time was funded by NASA, with a letter of support from
the Cassini mission to Saturn. The Cassini-Huygens mission is a
cooperative project of NASA, the European Space Agency, and the Italian
Space Agency. The mission is managed by JPL for NASA's Science Mission
Directorate, Washington. JPL is a division of the California Institute
of Technology in Pasadena, Calif.
NASA Probe Observes Meteors Colliding With Saturn's Rings
04.25.13
Five images of Saturn's rings, taken by NASA's Cassini spacecraft
between 2009 and 2012, show clouds of material ejected from impacts of
small objects into the rings. Image credit: NASA/JPL-Caltech/Space
Science Institute/Cornell
› Full image and caption
The meteoroids that NASA's Cassini spacecraft detected crashing into
Saturn's rings are comparable in size to the meteor that hurtled over
Russia in February 2013. Image credit: Copyright M. Ahmetvaleev
› Full image and caption
› Full image and caption
This illustration depicts the shearing of an initially circular cloud of
debris as a result of the particles in the cloud having differing
orbital speeds around Saturn. Image credit: NASA/Cornell
› Full image and caption
› View animated version of this graphic
› Full image and caption
› View animated version of this graphic
PASADENA, Calif. -- NASA's Cassini spacecraft has provided the first
direct evidence of small meteoroids breaking into streams of rubble and
crashing into Saturn's rings.
These observations make Saturn's rings the only location besides Earth,
the moon and Jupiter where scientists and amateur astronomers have been
able to observe impacts as they occur. Studying the impact rate of
meteoroids from outside the Saturnian system helps scientists understand
how different planet systems in our solar system formed.
The solar system is full of small, speeding objects. These objects
frequently pummel planetary bodies. The meteoroids at Saturn are
estimated to range from about one-half inch to several yards (1
centimeter to several meters) in size. It took scientists years to
distinguish tracks left by nine meteoroids in 2005, 2009 and 2012.
Details of the observations appear in a paper in the Thursday, April 25 edition of Science.
Results from Cassini have already shown Saturn's rings act as very
effective detectors of many kinds of surrounding phenomena, including
the interior structure of the planet and the orbits of its moons. For
example, a subtle but extensive corrugation that ripples 12,000 miles
(19,000 kilometers) across the innermost rings tells of a very large
meteoroid impact in 1983.
"These new results imply the current-day impact rates for small
particles at Saturn are about the same as those at Earth -- two very
different neighborhoods in our solar system -- and this is exciting to
see," said Linda Spilker, Cassini project scientist at NASA's Jet
Propulsion Laboratory in Pasadena, Calif. "It took Saturn's rings acting
like a giant meteoroid detector -- 100 times the surface area of the
Earth -- and Cassini's long-term tour of the Saturn system to address
this question."
The Saturnian equinox in summer 2009 was an especially good time to see
the debris left by meteoroid impacts. The very shallow sun angle on the
rings caused the clouds of debris to look bright against the darkened
rings in pictures from Cassini's imaging science subsystem.
"We knew these little impacts were constantly occurring, but we didn't
know how big or how frequent they might be, and we didn't necessarily
expect them to take the form of spectacular shearing clouds," said Matt
Tiscareno, lead author of the paper and a Cassini participating
scientist at Cornell University in Ithaca, N.Y. "The sunlight shining
edge-on to the rings at the Saturnian equinox acted like an
anti-cloaking device, so these usually invisible features became plain
to see."
Tiscareno and his colleagues now think meteoroids of this size probably
break up on a first encounter with the rings, creating smaller, slower
pieces that then enter into orbit around Saturn. The impact into the
rings of these secondary meteoroid bits kicks up the clouds. The tiny
particles forming these clouds have a range of orbital speeds around
Saturn. The clouds they form soon are pulled into diagonal, extended
bright streaks.
"Saturn's rings are unusually bright and clean, leading some to suggest
that the rings are actually much younger than Saturn," said Jeff Cuzzi, a
co-author of the paper and a Cassini interdisciplinary scientist
specializing in planetary rings and dust at NASA's Ames Research Center
in Moffett Field, Calif. "To assess this dramatic claim, we must know
more about the rate at which outside material is bombarding the rings.
This latest analysis helps fill in that story with detection of
impactors of a size that we weren't previously able to detect directly."
The Cassini-Huygens mission is a cooperative project of NASA, the
European Space Agency and the Italian Space Agency. NASA's Jet
Propulsion Laboratory, Pasadena, Calif., a division of the California
Institute of Technology, Pasadena, manages the Cassini-Huygens mission
for NASA's Science Mission Directorate in Washington. JPL designed,
developed and assembled the Cassini orbiter and its two onboard cameras.
The imaging team consists of scientists from the United States,
England, France and Germany. The imaging operations center is based at
the Space Science Institute in Boulder, Colo.
For images of the impacts and information about Cassini, visit:
and
Jia-Rui Cook 818-354-0850
Jet Propulsion Laboratory, Pasadena, Calif.
jccook@jpl.nasa.gov
Dwayne Brown 202-358-1726
NASA Headquarters, Washington
dwayne.c.brown@nasa.gov
Jet Propulsion Laboratory, Pasadena, Calif.
jccook@jpl.nasa.gov
Dwayne Brown 202-358-1726
NASA Headquarters, Washington
dwayne.c.brown@nasa.gov
NASA
Guillermo Gonzalo Sánchez Achutegui
ayabaca@gmail.com
ayabaca@hotmail.com
ayabaca@yahoo.com
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