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New findings from Saturn - part one

One of the questions about Saturn is why is it brighter relative to its age? It was supposed to be darker and colder. Answer to this question and revelations regarding the atmosphere and rings in this article

Saturn's Northern Hemisphere Jet Stream in Artificial Colors. Photo: NASA's Cassini spacecraft
Saturn's Northern Hemisphere Jet Stream in Artificial Colors. Photo: NASA's Cassini spacecraft

 

atmosphere
One of the questions about Saturn is why is it brighter relative to its age? It was supposed to be darker and colder. It turned out that layers of gas created by physical instability inside Saturn prevent the heat from escaping and this prevents it from cooling. Layers of Saturn's convection currents are similar to those active on Earth, in the oceans, places where there is warm, salty water that lies beneath a layer of cold, less salty water. The more saline layer prevents the formation of vertical currents between the layers and because of this the heat is not transferred efficiently (1). As one goes deeper into the atmosphere of Saturn, the atmospheric pressures keep increasing and so do the temperatures until at a certain point the atmosphere takes on the characteristics of a liquid and hence the resemblance to the Earth (author's hypothesis - Haim Mazar). Radar and radio microwave tests conducted by the Cassini spacecraft have shown that Saturn is a very dynamic planet and in many places it resembles Jupiter, more than previously thought. The measurements also showed that a quiet band at the equator is surrounded by turbulent bands like those of Jupiter, although different regions in the high latitudes of Saturn are unique to this planet. The microwave mapping revealed in unprecedented detail a stable atmospheric environment. It is possible to notice spots similar to arid and climatic desert areas and in places where the climate is hot and humid. Ammonia is widespread in the stable troposphere. The mapping also revealed areas where the ammonia is more dilute due to its high rate of condensation to liquid. For this reason the layer of the atmosphere below them is unstable. This scarcity of ammonia opens a window to look deeper into places where the atmosphere is warmer(2).

clouds
In a film produced from a series of photographs taken by the Cassini, clouds of a hurricane-like storm are seen moving around the North Pole near latitude 88.5 degrees north. The eye of the storm is 20 times larger than the eye of an average hurricane on Earth. The winds are measured by tracking small clouds for 5 hours. The wind speed in the inner ring is the highest, up to 530 km/h. These winds are four times faster than Earth's jet streams. The clouds in the center of the hurricane move around themselves at twice the speed of Saturn's rotation around itself, and their direction is counterclockwise, similar to hurricanes in the northern hemisphere of the Earth, only Saturn has no ocean. A similar phenomenon is also found in the southern hemisphere and its direction is similar to the direction of a hurricane in the southern hemisphere of the earth. On Earth, hurricanes start in the tropics and move around them. On Saturn's geo-locked polar hurricanes, the bright clouds form a tight spiral moving toward the center. This spiral can be a wave or a real movement of a particle moving towards the center from an external disturbance source. It may be a remnant of a cloud derived from a larger angular velocity closer to the center (3).

climate
Due to its inclination angle, 27 degrees, Saturn's pole undergoes climatic changes similar to Earth's. During the winter season, there is darkness at the poles for 7 years and following them 23 years there are changes in the illumination coming from the sun. The climatic changes do not affect the configuration of the hexagon in the North Pole nor its jet streams (4). On March 15, 2011, the largest storm observed until then was observed. Lightning was seen creating a phenomenon of electrical discharges known as Saturn electrostatic discharges similar to lightning on Earth and emitting radio waves in AM. The first detection of this storm was on December 5, 2010 and it continued on April 15, 2011. At the maximum activity of the storm, the lightning flashes continued at a rate of more than 10 times per second. The flashes were so frequent that the spacecraft could not track them. It was only on March 15, when the intensity of the lightning weakened, that it was possible to follow them. This was the first lightning storm observed in the Northern Hemisphere, raising the possibility that these storms erupt as the spring and summer seasons arrive. Spring in the Northern Hemisphere began in 2009 when sunlight began to move from the Southern Hemisphere to the Northern Hemisphere (5). So far the lightning has been seen on the night side of Saturn. Daylight lightning was first seen on March 6, 2011. The lightning was seen in the blue light. It could be that it really is their color or that the short exposure of the camera in the blue filter allowed for easier viewing during the short time that the lightning occurred. The diameter of the lightning is 200 km, its power is three billion watts and it lasts only one second. The conclusion reached by the researchers is that it is formed in clouds deep in the atmosphere, in places where water droplets freeze similar to lightning that forms on Earth (6).

Visible and infrared mapping of Saturn on February 24, 2011 showed large ammonia ice particles that were probably raised by a very strong storm in the northern hemisphere more than 50 km away. During this time the ammonia particles condensed into large crystals in the upper, icy part of the atmosphere (7).

Aurora
In March 2012, they managed to simultaneously measure the night glow of Saturn, the magnetic field and charged particles associated with it. In these measurements they wanted to obtain information about the electric currents that create these emissions. Usually the aurora photographs provide a lot of information about the electromagnetic relationship between the solar wind, the magnetosphere and the upper atmosphere. Changes in brightness provide information regarding changes in the magnetosphere. For the first time they made a comparison between the day side and the night side 8).

In 2014, the results of studies were published that provided proof of the theory that the glow of Saturn was created by breakdowns in the tail of Saturn's magnetosphere (magnetic tail). This phenomenon was observed in April and May 2013, part of a three-year study using the Hubble Space Telescope that examined the composition of the atmosphere. The glow shines strongly in ultra violet (9).

magnetosphere
Saturn has a long magnetic tail that resembles the tail of a comet and is called a magnetotail. This phenomenon has also been observed with Mercury, Jupiter, Uranus, Neptune and the Earth. This tail is found in planets that have a magnetic field. It appears that when bursts of particles from the solar wind hit Saturn the tail of its magnetic field collapses and then rebuilds. Some of the energy bursts around Saturn's poles travel at three times the speed of its rotation around itself. A combination of photographs from the Cassini and the Hubble telescope allows for a 360-degree image of Saturn at both poles (10).

radio waves

Saturn emits radio waves known as Saturn Kilometric Radiation which sound like car horn blasts. They change with every rotation of Saturn around itself in ranges of seconds and minutes. They come in pairs. The radio wave emission from the North Pole has a cycle of 10.6 hours and the emission at the South Pole has a cycle of 10.8 hours. These differences change with the seasons. The source of the differences between what is done in the North Pole and what is done in the South Pole is in the changes that occur in the winds at high altitudes between the Northern Hemisphere and the Southern Hemisphere. The back and forth oscillations in the glow of the poles correspond to changes in the radio waves. Between January and March 2009 just before the equinox. Radio waves and aurora complement each other because they are related to fluctuations in the magnetosphere. The flow of electrons moving into the atmosphere and creating the glow also emits radio waves and affects the magnetic field. For this reason, the researchers estimate that these changes are related to the influence of the sun on Saturn (11).

rings of saturn
On April 21, 2013, it became clear that "rain" falls on Saturn from the rings. This rain affects the molecular composition of the atmosphere and creates the bright, thin bands on its surface. This rain can also affect Saturn's glow (12).

The hexagon shape
Since the discovery of the hexagon in 1980 by Voyager 1, it has been geographically located in the same place and the same size. There were no changes in its configuration. The photographs taken by the Cassini spacecraft are of very high resolution, in the near-infrared wavelength, and they allow one to see a great deal of detail. You can see that the hexagon is very structured. Inside and outside of it you find concentric circles of clouds. The sides of the hexagon are rigid and act as a barrier. Storms moving at hundreds of kilometers per hour are unable to breach the sides of the hexagon (13). In a photograph taken on November 27, 2012, a hurricane storm can be seen inside the hexagon, which according to the researchers' assessment is a jet stream moving around the North Pole at a speed of 352 km/h (14).
The researchers concluded that the hexagon is a wavy jet stream that can be seen. It moves at a speed of 322 km/h and in the center is a massive storm moving around itself. Inside the hexagon there are few large haze particles and a concentration of small haze particles and outside it the phenomenon is the opposite. The particles cannot exit or enter the hexagon. The haze particles grow when the sun shines on the atmosphere (15). In a series of photographs taken over 10 hours on December 10, 2012, it is possible to distinguish different types of clouds and small eddies. Some move clockwise. The hexagon and the hurricane move counterclockwise. Some of the storms drift along the northern side of the hexagon and look like a racetrack. The largest of these storms rotates around itself at a speed of 3,500 km/h (16). In May 2013 it was reported about a hurricane inside the hexagon that was photographed in high resolution. The diameter of the hurricane's eye is 2,000 km, 20 times larger than any average hurricane on Earth. Clouds at the outer edge of the eye hurricane move at a speed of 528 km/h (17).

The hexagon was photographed in a series of images every time Xsini passed over or near the North Pole. It turned out that the changes from photograph to photograph are dramatic. For the purpose of illustration, two photographs are shown here and they are JPG WOO078138 (18) and the photograph taken immediately after it JPG WOO078139 (19). These photos are from a series taken on December 10, 2012. In the first photo the entire hexagon is very dark and in the one after that you see a lot of internal swirls. The configuration of the vortices is concentric. The time difference between a photo and a photo is seconds to minutes. A new research field will be opened here regarding the dynamics of the formation of the vortices inside the hexagon, the changes in its internal geometry and the sharp transitions between the dark and light colors. Another and interesting issue in itself is why there is no passage of hurricanes from the hexagon out and vice versa. Since the hexagon was already observed by Voyager 1 and its geographic location has not changed since then, the questions beg - what stabilizes it where it is and why? The observations show that the hexagon has some kind of sides. The questions are - what is Obayin? What are they made of? What is their depth? And is there a difference in the atmospheric pressures between the inner rim of the hexagon and the outer rim? How do atmospheric pressures and temperatures change as you go deeper inside the hexagon? How and to what extent is the hexagon affected by the change of seasons? Is there hurricane flow into and out of the hexagon under the sides? One should think about a spaceship that will be launched into the hexagon and perhaps insert the Cassini itself into it when it finishes its mission.
Sources
1. 'Saturn's Youthful appearance explained"1.5.2013

2nd. " Saturn's hidden turbulence revealed" 17.9.2013

3. PIA14947: Saturn hurricane movie

4nd. " Saturn's hexagon : An amazing phenomenon 8. 4.2014

5. PIA14310: Lighting strikes at Saturn

6. "Cassini spots 100 mile wide lighting flashes on Saturn" 18.7.2012

7. PIA14119: Updraft of large ammonia crystals in Saturn storm
http://photojournal.jpl.nasa.gov/catalog/PIA14119
8. "Cassini makes simultaneous measurements of Saturn's night side aurora electric and current stream" 5.4.2012/XNUMX/XNUMX
http://www.spacedaily.com/reports/Cassini_Makes_Simultaneous_Measurments_ Of_ Saturn’s _Night_ Side _Aurora _Electric _And _Current _ Stream_999.html
9. 'Smoking gun evidence for the theory that Saturn's collapsing magnetic tail causes auroras "19.5.2014

10. "Hubble sees flickering light display on Saturn" 27.5.2014

11. "Cassini finds Saturn sends mixed signals" 23.5.2011
http://www.spacedaily.com/reports/Cassini_Finds_Saturn_Sends_Mixed_Signals_999.html
12. Kramer M. - "Search for northern lights on Saturn takes off" 22.4.2013
http;//www.livescience.com/28944-saturn- northern-lights-search.html
13. Ian O'Neill – "Saturn hexagon north pole : What is causing it?" 13.10.2008
Saturn's Hexagonal North Pole: What is Causing It?
14. PIA14945: Spring at the north pole
http://photojournal.jpl.nasa.gov/catalog/PIA14945
15. "Cassini spacecraft obtains best views of Saturn hexagon" 6.12.2013
http://www.spacedaily.com/reports/Cassini_Spacecraft_Obtains_Best_Views_Of _Saturn_ Hexagon_999.html
16. PIA17652: In full view: Saturn's steaming hexagon
http://photojournal.jpl.nasa.gov/catalog/PIA17652
17. "Cassini gets close up views of large hurricane on Saturn" 2.5.2013

18. Image W00078138jpg

19. Image W00078139jpg

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