Hola amigos: A VUELO DE UN QUINDE EL BLOG., la Revista National Geographic, ha elaborado un reportaje sobre el planeta Saturno, que están desapareciendo sus icónicos anillos, observaciones efectuadas en base a investigaciones de las zonas espaciales que envió NASA, tales como : Sonda Cassini , Sondas Voyager 1 y 2 en su periplo por el sistema solar.
NASA, en inglés nos detalla minuciosamente con VIDEO como está desapareciendo los anillos de Saturno.
https://www.nasa.gov/press-release/goddard/2018/ring-rain
NASA Research Reveals Saturn is Losing Its Rings at “Worst-Case-Scenario” Rate
https://www.nationalgeographic.com.es/ciencia/actualidad/las-fotos-mas-detalladas-jamas-tomadas-los-anillos-saturno_11114/1
La sonda Cassini continúa haciendo historia y acaba de enviar las fotografías más cercanas y detalladas de los impresionantes anillos helados de Saturno
https://www.nationalgeographic.com.es/ciencia/actualidad/saturno-esta-perdiendo-sus-anillos_13696
Los icónicos anillos del gigante gaseoso podrían desaparecer en 300 millones de años
Polo norte de Saturno y sus anillos
Redacción
20 de diciembre de 2018
Hace ya unas décadas que las sondas Voyager 1 y 2, en su periplo por el sistema solar, se acercaran a las inmediaciones del planeta Saturno y estimaran que el planeta venía perdiendo sus anillos. Ahora una nueva investigación de la NASA confirma que el gigante gaseoso está perdiendo sus icónicos anillos, y que lo está haciendo además a la tasa máxima que en su día estipularon las observaciones de las Voyager 1 y 2.
Más información
Las fotos más detalladas jamás tomadas de los anillos de Saturno
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Fotografías
Según la agencia americana los anillos se están viendo arrastrados al planeta debido a la gravedad del gigante gaseoso en forma de una lluvia polvorienta de partículas de hielo bajo la influencia su campo magnético. James O'Donoghue del Centro de Vuelo Espacial Goddard de la NASA y autor principal de estudio titulado Observations of the chemical and thermal response of ‘ring rain’ on Saturn’s ionosphere publicado en la revista especializada Icarus, declara que el flujo de agua que se genera desde los anillos hacia el planeta es suficiente como para llenar una piscina olímpica en tan solo media hora.
"Es poco probable que el sistema de anillos tenga más de 100 millones de años"
"A este ritmo todo el sistema de anillos desaparecerá en 300 millones de años", afirma. "Por otro lado, la sonda Cassini, también nos ha ofrecido datos sobre el anillo medio de Saturno situado en el ecuador,según los cuales la vida media de estos se ha estipulado en tan solo 100 millones de años. Esto no es nada comparado con la edad de Saturno de más de 4.000 millones de años", añade el investigador.
Lluvia espacial a las afueras Saturno
Desde muy temprano los científicos se han preguntado si los anillos de Saturno se formaron junto al planeta o si bien su formación fue posterior. La nueva investigación favorece este último escenario, lo que indica que es poco probable que tengan más de 100 millones de años. "Tenemos la suerte de estar cerca para ver el sistema de anillos de Saturno, que parece estar en el ecuador de su vida. Sin embargo, si los anillos son temporales, tal vez nos perdimos ver sistemas de anillos gigantes en Júpiter, Urano y Neptuno" agrega O'Donoghue.
Se han propuesto diversas teorías para el origen de los anillos. Si es se formaron más tarde en la vida del planeta, podría deberse al haberse cruzado pequeñas lunas heladas con la órbita de Saturno y chocar contra el planeta.
"Tal vez nos perdimos ver sistemas de anillos gigantes en Júpiter, Urano y Neptuno"
Los anillos de Saturno son en su mayoría trozos de hielo de agua que varían en tamaño: desde granos de polvo microscópicos hasta cantos rodados de varios metros de ancho. De este modo, las partículas de los anillos quedan atrapadas en un acto de equilibrio entre la gravedad de Saturno, que quiere atraerlas al planeta, y su velocidad orbital, que quiere arrojarlas al espacio.
Más información
Misterioso hexágono en Saturno
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Las partículas más diminutas pueden cargarse eléctricamente por la luz ultravioleta del sol o por las nubes de plasma que emanan de los anillos. Cuando esto sucede, las partículas pueden sentir el tirón del campo magnético de Saturno. En algunas partes de los anillos, una vez cargadas las partículas, el equilibrio de fuerzas entre partículas cambia drásticamente, y es la gravedad del planeta que gana la batalla empujando las partículas hacia la atmósfera superior del planeta.
Las fotos más detalladas jamás tomadas de los anillos de Saturno
La sonda Cassini continúa haciendo historia y acaba de enviar las fotografías más cercanas y detalladas de los impresionantes anillos helados de Saturno
La influencia gravitatoria de sus lunas
El anillo A, a unos 134.500 kilómetros de Saturno, tiene distintas densidades en función de la acumulación de partículas. En esta imagen, más cercana que nunca, se pueden ver aglutinaciones de material y las “olas” creadas por la influencia gravitatoria de las lunas Epimeteo y Jano.
Foto: NASA/JPL-Caltech
Órbitas finales alrededor de Saturno
Recreación artística que muestra las dos fases finales de Cassini alrededor de Saturno: cerca del anillo F (en gris); y entre el planeta y el anillo más interior (en azul). La línea naranja indica la inmersión final en Saturno en septiembre de 2017.
Imagen: NASA / JPL-Caltech
Anillo B
Esta imagen muestra una región del anillo exterior B de Saturno con un detalle dos veces mayor de lo que nunca se había conseguido, lo que permite a los científicos conocer en profundidad estas estructuras.
Foto: NASA/JPL-Caltech
Manchas brillantes
Como apuntan desde la NASA, en esta imagen de una región del anillo A de Saturno existen muchas pequeñas manchas brillantes debido a los rayos cósmicos y la radiación de partículas cargadas cerca del planeta.
Foto: NASA/JPL-Caltech
Imágenes todavía más cercanas
Aunque esta imagen también ha permitido ver la zona exterior del anillo B de Saturno con el doble del nivel de detalle alcanzado hasta el momento, los científicos son conscientes de que quedan muchos detalles por descubrir cuando se consigan imágenes todavía más cercanas.
Foto: NASA/JPL-Caltech
Javier Flores
1 de febrero de 2017
Las fotos más detalladas jamás tomadas de los anillos de Saturno
Aunque las imágenes se parezcan más a un cuadro de Pollock, Picasso o Mondrian, la verdad es que se tratan de las fotografías más cercanas y detalladas que se han tomado en toda la historia de los misteriosos anillos de Saturno. Como explica Matthew Tiscareno , uno de los científicos que trabajan en el proyecto de estudio de los anillos de Saturno en el Instituto SETI, "estas imágenes cercanas muestran una visión completamente nueva en los anillos de Saturno, y en los próximos meses esperamos recibir más datos sobre otras partes de los anillos que están más cerca del propio planeta".
La misión Cassini-Huygens es uno de los proyectos más fructíferos de toda la historia de la exploración espacial. Fue lanzada en octubre de 1997 y no llegó a Saturno hasta 2004 tras un largo periplo por el espacio de más de siete años. Aunque no fue el primer invento humano que llegaba a este planeta del sistema solar sí que fue el primer artefacto que consiguió orbitarlo y estudiar más a fondo cómo se comporta Saturno, las lunas que no paran de girar a su alrededor y sus archiconocidos anillos.
Gracias a él sabemos que en Encelado, una de las lunas de Saturno, existen géiseres en su superficie, que otra de sus lunas, Titán, existen lagos de metano líquido, que el polo norte del planeta cambia de color… Sin embargo su ocaso está cada día más cerca y morirá quemada en la atmósfera del gigantesco Saturno a lo largo de 2017. Eso sí, los científicos todavía esperan que la sonda envíe algunos nuevos e interesantes datos antes de que esto ocurra.
NATIONAL GEOGRAPHICNASA Research Reveals Saturn is Losing Its Rings at “Worst-Case-Scenario” Rate
New NASA research confirms that Saturn is losing its iconic rings at the maximum rate estimated from Voyager 1 & 2 observations made decades ago. The rings are being pulled into Saturn by gravity as a dusty rain of ice particles under the influence of Saturn’s magnetic field.
This video explores how Saturn is losing its rings at a rapid rate in geologic timescales and what that reveals about the planet’s history.
Credits: NASA’s Goddard Space Flight Center/David Ladd
“We estimate that this ‘ring rain’ drains an amount of water products that could fill an Olympic-sized swimming pool from Saturn’s rings in half an hour,” said James O’Donoghue of NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “From this alone, the entire ring system will be gone in 300 million years, but add to this the Cassini-spacecraft measured ring-material detected falling into Saturn’s equator, and the rings have less than 100 million years to live. This is relatively short, compared to Saturn’s age of over 4 billion years.” O’Donoghue is lead author of a study on Saturn’s ring rain appearing in Icarus December 17.
This image was made as the Cassini spacecraft scanned across Saturn and its rings on April 25, 2016, capturing three sets of red, green and blue images to cover this entire scene showing the planet and the main rings. The images were obtained using Cassini's wide-angle camera at a distance of approximately 1.9 million miles (3 million kilometers) from Saturn and at an elevation of about 30 degrees above the ring plane.
Credits: NASA/JPL-Caltech/Space Science Institute
Scientists have long wondered if Saturn was formed with the rings or if the planet acquired them later in life. The new research favors the latter scenario, indicating that they are unlikely to be older than 100 million years, as it would take that long for the C-ring to become what it is today assuming it was once as dense as the B-ring. “We are lucky to be around to see Saturn’s ring system, which appears to be in the middle of its lifetime. However, if rings are temporary, perhaps we just missed out on seeing giant ring systems of Jupiter, Uranus and Neptune, which have only thin ringlets today!” O’Donoghue added.
Various theories have been proposed for the ring’s origin. If the planet got them later in life, the rings could have formed when small, icy moons in orbit around Saturn collided, perhaps because their orbits were perturbed by a gravitational tug from a passing asteroid or comet.
An artist's impression of how Saturn may look in the next hundred million years. The innermost rings disappear as they rain onto the planet first, very slowly followed by the outer rings.
Credits: NASA/Cassini/James O'Donoghue
The first hints that ring rain existed came from Voyager observations of seemingly unrelated phenomena: peculiar variations in Saturn’s electrically charged upper atmosphere (ionosphere), density variations in Saturn’s rings, and a trio of narrow dark bands encircling the planet at northern mid-latitudes. These dark bands appeared in images of Saturn’s hazy upper atmosphere (stratosphere) made by NASA’s Voyager 2 mission in 1981.
In 1986, Jack Connerney of NASA Goddard published a paper in Geophysical Research Letters that linked those narrow dark bands to the shape of Saturn’s enormous magnetic field, proposing that electrically charged ice particles from Saturn’s rings were flowing down invisible magnetic field lines, dumping water in Saturn’s upper atmosphere where these lines emerged from the planet. The influx of water from the rings, appearing at specific latitudes, washed away the stratospheric haze, making it appear dark in reflected light, producing the narrow dark bands captured in the Voyager images.
Saturn’s rings are mostly chunks of water ice ranging in size from microscopic dust grains to boulders several yards (meters) across. Ring particles are caught in a balancing act between the pull of Saturn’s gravity, which wants to draw them back into the planet, and their orbital velocity, which wants to fling them outward into space. Tiny particles can get electrically charged by ultraviolet light from the Sun or by plasma clouds emanating from micrometeoroid bombardment of the rings. When this happens, the particles can feel the pull of Saturn’s magnetic field, which curves inward toward the planet at Saturn’s rings. In some parts of the rings, once charged, the balance of forces on these tiny particles changes dramatically, and Saturn’s gravity pulls them in along the magnetic field lines into the upper atmosphere.
Once there, the icy ring particles vaporize and the water can react chemically with Saturn’s ionosphere. One outcome from these reactions is an increase in the lifespan of electrically charged particles called H3+ ions, which are made up of three protons and two electrons. When energized by sunlight, the H3+ ions glow in infrared light, which was observed by O’Donoghue’s team using special instruments attached to the Keck telescope in Mauna Kea, Hawaii.
Their observations revealed glowing bands in Saturn’s northern and southern hemispheres where the magnetic field lines that intersect the ring plane enter the planet. They analyzed the light to determine the amount of rain from the ring and its effects on Saturn’s ionosphere. They found that the amount of rain matches remarkably well with the astonishingly high values derived more than three decades earlier by Connerney and colleagues, with one region in the south receiving most of it.
The team also discovered a glowing band at a higher latitude in the southern hemisphere. This is where Saturn’s magnetic field intersects the orbit of Enceladus, a geologically active moon that is shooting geysers of water ice into space, indicating that some of those particles are raining onto Saturn as well. “That wasn’t a complete surprise,” said Connerney. “We identified Enceladus and the E-ring as a copious source of water as well, based on another narrow dark band in that old Voyager image.” The geysers, first observed by Cassini instruments in 2005, are thought to be coming from an ocean of liquid water beneath the frozen surface of the tiny moon. Its geologic activity and water ocean make Enceladus one of the most promising places to search for extraterrestrial life.
Saturn’s moon Enceladus drifts before the rings and the tiny moon Pandora in this view that NASA’s Cassini spacecraft captured on Nov. 1, 2009. The entire scene is backlit by the Sun, providing striking illumination for the icy particles that make up both the rings and the jets emanating from the south pole of Enceladus, which is about 314 miles (505 km) across. Pandora, which is about (52 miles, 84 kilometers) wide, was on the opposite side of the rings from Cassini and Enceladus when the image was taken. This view looks toward the night side on Pandora as well, which is lit by dim golden light reflected from Saturn.
Credits: NASA/JPL-Caltech/Space Science Institute
The team would like to see how the ring rain changes with the seasons on Saturn. As the planet progresses in its 29.4-year orbit, the rings are exposed to the Sun to varying degrees. Since ultraviolet light from the Sun charges the ice grains and makes them respond to Saturn’s magnetic field, varying exposure to sunlight should change the quantity of ring rain.
The research was funded by NASA and the NASA Postdoctoral Program at NASA Goddard, administered by the Universities Space Research Association. The W.M. Keck Observatory is operated as a scientific partnership among the California Institute of Technology, the University of California, and NASA, and the data in the form of its files are available from the Keck archive. The authors wish to recognize the significant cultural role and reverence that the summit of Mauna Kea has within the indigenous Hawaiian community; they are fortunate to have the opportunity to conduct observations from this mountain.
Bill Steigerwald / Nancy Jones
NASA Goddard Space Flight Center, Greenbelt, Maryland
301-286-8955 / 301-286-0039
william.a.steigerwald@nasa.gov / nancy.n.jones@nasa.gov
NASA Goddard Space Flight Center, Greenbelt, Maryland
301-286-8955 / 301-286-0039
william.a.steigerwald@nasa.gov / nancy.n.jones@nasa.gov
Last Updated: Dec. 19, 2018
Editor: Bill Steigerwald
Hubble Takes Portrait of Opulent Ring World
Saturn is by far the solar system’s most photogenic planet, and in this latest Hubble Space Telescope snapshot it is especially so because Saturn’s magnificent ring system is near its maximum tilt toward Earth (which was in 2017).
Hubble was used to observe the planet on June 6, 2018, when Saturn was only approximately 1.36 billion miles from Earth, nearly as close to us as it ever gets.
Saturn was photographed as it approached a June 27 opposition, when the planet is directly opposite to the Sun in the night sky and is at its yearly closest distance to the Earth. Though all of the gas giants boast rings, Saturn’s are the largest and most spectacular, stretching out eight times the radius of the planet.
Saturn’s stunning rings were first identified as a continuous disk around the planet by Dutch astronomer Christiaan Huygens in 1655. 325 years later, NASA’s Voyager 1 spacecraft flyby of Saturn resolved thousands of thin, fine ringlets. Data from NASA’s Cassini mission suggests the rings formed 200 million years ago, roughly around the time of the dinosaurs and Earth’s Jurassic period. The gravitational disintegration of one of Saturn’s small moons created myriad icy debris particles, and collisions today likely continually replenish the rings.
Visible in this Hubble image are the classic rings as recorded by early skywatchers. From the outside in are the A ring with the Encke Gap, the Cassini Division, the B ring, and the C ring with the Maxwell Gap.
Saturn’s appearance changes due to its seasons, caused by the planet’s 27-degree axial tilt. It is now summer in Saturn’s northern hemisphere and the atmosphere is more active. This may be responsible for a string of bright clouds visible near the northern polar region that are the remnants of a disintegrating storm. Small, mid-latitude puffs of clouds are also visible. Hubble’s view also resolves a hexagonal pattern around the north pole, a stable and persistent wind feature discovered during the Voyager flyby in 1981.
Saturn’s colors come from hydrocarbon hazes above the ammonia crystals in the upper cloud layers. Unseen lower-level clouds are either ammonium hydrosulfide or water. The planet’s banded structure is caused by the winds and the clouds at different altitudes.
This is the first image of Saturn taken as part of the Outer Planet Atmospheres Legacy (OPAL) project. OPAL is helping scientists understand the atmospheric dynamics and evolution of our solar system’s gas giant planets.
Credits: NASA, ESA, Amy Simon and the OPAL Team, and J. DePasquale (STScI)
Last Updated: July 27, 2018
Editor: Karl Hille
Hubble observes energetic lightshow at Saturn’s north pole
30 August 2018
Astronomers using the NASA/ESA Hubble Space telescope have taken a series of spectacular images featuring the fluttering auroras at the north pole of Saturn. The observations were taken in ultraviolet light and the resulting images provide astronomers with the most comprehensive picture so far of Saturn’s northern aurora.
In 2017, over a period of seven months, the NASA/ESA Hubble Space Telescope took images of auroras above Saturn’s north pole region using the Space Telescope Imaging Spectrograph. The observations were taken before and after the Saturnian northern summer solstice. These conditions provided the best achievable viewing of the northern auroral region for Hubble.
On Earth, auroras are mainly created by particles originally emitted by the Sun in the form of solar wind. When this stream of electrically charged particles gets close to our planet, it interacts with the magnetic field, which acts as a gigantic shield. While it protects Earth’s environment from solar wind particles, it can also trap a small fraction of them. Particles trapped within the magnetosphere — the region of space surrounding Earth in which charged particles are affected by its magnetic field — can be energised and then follow the magnetic field lines down to the magnetic poles. There, they interact with oxygen and nitrogen atoms in the upper layers of the atmosphere, creating the flickering, colourful lights visible in the polar regions here on Earth [1].
However, these auroras are not unique to Earth. Other planets in our Solar System have been found to have similar auroras. Among them are the four gas giants Jupiter, Saturn, Uranus and Neptune. Because the atmosphere of each of the four outer planets in the Solar System is — unlike the Earth — dominated by hydrogen, Saturn’s auroras can most easily be seen in ultraviolet wavelengths; a part of the electromagnetic spectrum which can only be studied from space.
Hubble allowed researchers to monitor the behaviour of the auroras at Saturn's north pole over an extended period of time. The Hubble observations were coordinated with the “Grand Finale” of the Cassini spacecraft, when the spacecraft simultaneously probed the auroral regions of Saturn [2]. The Hubble data allowed astronomers to learn more about Saturn’s magnetosphere, which is the largest of any planet in the Solar System other than Jupiter.
The images show a rich variety of emissions with highly variable localised features. The variability of the auroras is influenced by both the solar wind and the rapid rotation of Saturn, which lasts only about 11 hours. On top of this, the northern aurora displays two distinct peaks in brightness — at dawn and just before midnight. The latter peak, unreported before, seems specific to the interaction of the solar wind with the magnetosphere at Saturn’s solstice.
The main image presented here is a composite of observations made of Saturn in early 2018 in the optical and of the auroras on Saturn’s north pole region, made in 2017, demonstrating the size of the auroras along with the beautiful colours of Saturn.
Hubble has studied Saturn's auroras in the past. In 2004, it studied the southern auroras shortly after the southern solstice (heic0504) and in 2009 it took advantage of a rare opportunity to record Saturn when its rings were edge-on (heic1003). This allowed Hubble to observe both poles and their auroras simultaneously.
Notes
[1] The auroras here on Earth have different names depending on which pole they occur at. Aurora Borealis, or the northern lights, is the name given to auroras around the north pole and Aurora Australis, or the southern lights, is the name given for auroras around the south pole.
[2] Cassini was a collaboration between NASA, ESA and the Italian Space Agency. It spent 13 years orbiting Saturn, gathering information and giving astronomers a great insight into the inner workings of Saturn. Cassini took more risks at the end of its mission, travelling through the gap between Saturn and its rings. No spacecraft had previously done this, and Cassini gathered spectacular images of Saturn as well as new data for scientists to work with. On 15 September 2017 Cassini was sent on a controlled crash into Saturn.
More information
The Hubble Space Telescope is a project of international cooperation between ESA and NASA.
Image credit: NASA, ESA & L. Lamy
Links
Contacts
Laurent LamyObservatoire de Paris
Paris, France
Tel: +33 145 077668
Email: laurent.lamy@obspm.fr
Mathias Jäger
ESA/Hubble, Public Information Officer
Garching, Germany
Tel: +49 176 62397500
Email: mjaeger@partner.eso.org
NASA
Guillermo Gonzalo Sánchez Achutegui
ayabaca@gmail.com
ayabaca@yahoo.com
ayabaca@hotmail.com
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