With its smooth, bright surface of water ice, cut through by long, linear fractures, the moon of Jupiter Europe is a strange world, which is only slightly smaller than the Earth. It is believed that Europe has a rocky mantle, an iron core and an ocean of salt water hidden behind its frozen ice shell - it is so far from the fiery heat of our Star, the Sun, that its ocean surface is globally frozen. In Europe’s many fractures, as well as in spotty areas on its cracked, egg-shell-like surface, there is a mysterious dark reddish-brown material whose composition has not been determined, but which may contain valuable information about a distant icy moon as a living world. . In May 2015, it was announced that NASA research finally shed light on this mystery - laboratory experiments show that dark material covering some geological features on the unusual, cracked surface of Europe probably represents sea salt from the subsurface ocean, discolored exposure .
The existence of sea salt coloring Europe’s frozen crust indicates that the global ocean interacts with its rocky seabed. This type of interaction is an important consideration in determining what kind of ice, distant lunar world can potentially feed on life.
A study describing this new study will appear in the journal Letters of geophysical research. It is available online.
“We have many questions about Europe, the most important and the most difficult to answer, is there life? Studies like this are important because it focuses on questions that we can definitively answer, such as whether Europe is suitable for life. When we receive these answers, we can solve a broader question about life in the ocean under the ice shell of Europe, ”Dr. Kurt Niebuhr said in NASA on May 12, 2015. Press release of the Jet Propulsion Laboratory (JPL). Dr. Niebur is an Outer Planet scientist at NASA headquarters in Washington, DC. JPL located in Pasadena, California.
Enchanted, Icy Moon-World
Discovered on January 8, 1610 by Galileo Galilei, Europe is a frigid, fascinating little moon world. Europa Opening along with three others Galilean moon, was first discovered the moon orbiting a planet other than Earth.
Under the shattered, tortured, spotty crust of ice on this moon, there is probably a giant, global ocean — the sixth largest lunar color in our solar system. Despite their small size, very few bodies cast a spell on astronomers as much as this mixed, cracked, strange little world. This is because, where there is liquid water, life, as we know it, can also exist.
Europe is named after the daughter of Agenor in ancient Greek mythology, who was kidnapped by Zeus (the Greek equivalent of Roman Jupiter), who took the form of a white bull. The gentle beast was so fascinated by Europe that it adorned it with flowers and rode on its back. Of course, Zeus took advantage of the situation and went with her to the ocean on the island of Crete, where, after his metamorphosis, he again turned into his real form.
Europe is one of the major quarters Galilean moons circled around the planet gas giant Jupiter. The four moons - Io, Europa, Ganymede and Callisto - are collectively called Galilean moons in honor of their discoverer, who noticed them when he peered into the dark, starry, winter night sky over Padua with his small primitive "podzol glass" - one of the first telescopes that could be used for astronomical purposes. Both Ganymede and Callisto are icy rocky lunar worlds, and Ganymede is the largest moon in our Solar System. Io, however, is a small hellish sphere, covered with scars and pockmarked with fiery volcanoes, and abundantly filled with sulfur.
For decades, bizarre mingled with ice destruction on Europe, chaos , were strange regions of uncertain, mysterious origin. Indeed, the bewilderment of regions such as chaos were not seen anywhere else in our solar system. However, it is now believed that these strange chaos they were formed by the movements of a moving global ocean whirling under the ice shell of Europe.
Europe of the planets of its planet every 3.5 days and locked up by the force of gravity to Jupiter in such a way that the same hemisphere of the small moon always refers to its parent planet. Since the Europa orbit is a bit elliptical (outside the circle), its distance from Jupiter varies. It creates hot flashes that stretch and relax its surface. The tides are due to the fact that Jupiter’s gravity is slightly stronger on the near side of Europe than on the far side, and the magnitude of this variation changes as Europe moves in its orbit around its planet. The bending resulting from the tides provides energy for the Europa ice shell, thus forming linear cracks that destroy its surface. If the ocean of Europe really exists, the tides can also create volcanic or hydrothermal activity on the seabed and thus provide valuable nutrients that could make the ocean a comfortable abode for life.
There are only a small number of craters porting the frozen surface of Europa. This indicates that the surface of the moon is probably no more than 40-90 million years old, which by geological standards is quite young. Despite the fact that Europa was visited by a sister spacecraft duet - Pioneer 10 and Pioneer 11 - back in the early 1970s, and the twin Voyagers in 1979, these early visits sent only some grainy, dim pictures to Earth. However, as it was wrong, these first images revealed enough about this intriguing little lunar world to make it an object of passion. The icy plains of pale yellow could see in navigator images, and they were also variegated with strange red and brown areas. Long fractures could also be seen, and they extended thousands of miles over the cracked, frozen bark. On Earth, similar fractures show such features as high mountains and deep canyons. However, nothing exceeded a few kilometers on the lunar world. Indeed, Europe has demonstrated one of the smoothest surfaces of the entire solar system!
NASA is very successful Galileo The mission, which studied the Jupiter system from 1995 to 2003, made several flybids over Europe. He collected the closest images to date on the broken surface of a small moon, watching strange pits and domes that reflected that the ice could slowly roll over, or convective , as a result of the heat coming from below. In addition, strange interest was of particular interest. chaos who showed confusing blocking, broken landscapes covered with a mysterious reddish material. Planetary scientists studying Galileo the mission data suggested that chaos regions should be areas where geological activity has disturbed another very smooth surface of Europe. In 2011, an intriguing idea was proposed that chaos are areas where the surface collapses above lake lakes located inside the ice.
In 2013, NASA announced that they obtained amazing testimonies from astronomers using Hubble Space Telescope that Europe could actively release water plumes into space. This discovery stimulated great excitement among scientists, because it indicated that the small lunar world is still geologically active. Plumes can be explored in future missions so that Cassini spaceships through the plumes of Saturn's Moon Enceladus.
Europe is especially intriguing because it is part of our Sun family, which has potentially huge amounts of liquid water, as well as geological activity that can allow the exchange of chemicals from the surface with a watery medium, ice. For this reason, Europe could become the most promising world in our solar system to search for signs of modern life.
One of the most important measurements made Galileo The mission showed that the magnetic field of Jupiter was disturbed in the space surrounding Europe. This important measurement convincingly indicates that an ice hole contains a special type of magnetic field, a deep layer of some electrically conductive liquid circulating around the frozen Europa shell. Because of the ice makeup of Europe, astronomers believe that the most promising material for creating this particular magnetic signature is the global ocean of salt water.
Future missions to Europe are likely to try to confirm the presence of their global saltwater ocean. Also of great interest is the composition of reddish material on the icy crust of Europe. Astronomers would like to know if this material contains valuable information about the composition of the ocean and whether the material is moving between the surface and the interior.
Europa In A Can
For more than ten years, astronomers have struck a composition of strange dark material that covers long linear features on the ice of Europe. His connection with youthful sites indicates that the material is overflowing from the inside of the moon. However, limited data was available, and the composition of the mysterious material remained uncertain.
“If this is only salt from the ocean below, it would be a simple and elegant solution for dark, mysterious material,” said leading researcher Dr. Kevin Rook on May 12, 2015 Press release JPL. Dr. Rook is a planetary scientist at Laboratory of jet propulsion.
It is well known that Europe is constantly shaving off the radiation created by Jupiter’s strong magnetic field. Electrons and ions crash into the icy lunar frozen crust with the power of a particle accelerator. Theories developed to explain the mysterious nature of dark material include the idea that this radiation is a likely star player in the drama that creates it.
Earlier studies using data obtained from Galileo , and various other telescopes, attributed these strange spots on the surface of Europe to compounds containing sulfur and magnesium. Although radiation-treated sulfur can explain some of the colors observed on frozen European bark, new experiments show that irradiated salts can take color into account in the youngest regions of Europe.
To determine the true nature of the dark material, Dr. Rook and his coauthor Dr. Robert Carlson, also JPL , created a simulated Europa surface area in a laboratory test apparatus designed to identify potential candidate substances. For each candidate material, they collected spectra encoded in the light reflected by the compounds. Spectra are like chemical fingerprints.
“We call it our Europe at the bank. The laboratory setup simulates the conditions on the surface of Europe in terms of temperature, pressure and radiation. Hand in May 12, 2015 Press release JPL.
For this study, astronomers tested samples of sodium chloride, which in their vacuum chamber at a cold surface temperature in Europe were -280 degrees Fahrenheit, called “common salt”, along with mixtures of salt and water. They then battled with electron-beam solonchaks to mimic the powerful radiation on the frozen Europa crust.
After several tens of hours of exposure to this inhospitable environment, which corresponds to Europe to a century, salt samples that began with white, like ordinary table salt, turned into a yellowish-brown color, similar to features on a distant, cold moon.
Scientists have discovered that the color of these samples, measured in their spectra, showed a strong resemblance to the color observed in the cracks in Europe, which were displayed Galileo.
“This paper suggests that the chemical signature of radiation sodium chloride is confused with data on spacecraft for European mystery materials,” continued Dr. Ruud, May 12, 2015 Press release JPL.
In addition, the longer the samples were exposed to radiation, the darker their color. Dr. Rood believes that scientists can use this type of color variation to help them determine the age of geological features and material ejected from any plumes that may exist in Europe.
Early observations in the telescope reflected the tempting suggestions of spectral features observed by scientists in their irradiated salts. However, no telescope on or around the planet can monitor Europe with sufficient resolution to identify signs with confidence. Astronomers suggest that this could be achieved by future observations with a spacecraft visiting Europe.
