Next stop the ocean worlds of Enceladus and Europa
Space news (planetary science: water worlds of the solar system; Enceladus and Europa) –planets and moons around the solar system and exoplanets across the universe covered with water–
The solar system’s awash in water! NASA missions have provided verifiable facts showing ocean worlds and moons exist in our solar system and beyond,other than Earth. Planetary bodieswhere water is locked in a frozen embrace and even flowing beneath miles of ice. Liquid water exobiologists are keen to explore for life forms they would love to meet and get to know a little better during the next phase of the human journey to the beginning of space and time. Watch this YouTube video on NASA’s search for life on the ocean worlds of the solar system.
Papers published bythe journal Science and written by Cassini mission scientists and researchers working with the Hubble Space Telescope indicate hydrogen gas believed pouring from the subsurface ocean of Enceladus could potentially provide chemical energy life could use to survive and evolve. Watch this YouTube videocalled “NASA: Ingredients for Life at Saturn’s moon Enceladus“, itshowsthe proof scientists used to come to these conclusions. Their work provides new insights concerning possible oceans of water on moons of Jupiter and Saturn and other ocean moons in the solar system and beyond.
“This is the closest we’ve come, so far, to identifying a place with some of the ingredients needed for a habitable environment,” said Thomas Zurbuchen, associate administrator for NASA’s Science Mission Directorate at Headquarters in Washington. ”These results demonstrate the interconnected nature of NASA’s science missions that are getting us closer to answering whether we are indeed alone or not.”
Researchers believe they have found evidence indicating hydrogen gas could be pouring out of hydrothermal vents on the floor of Saturn’s moon Enceladus and into these oceans of water. Any microbes existing in these distant waters could use this gas as a form of chemical energy to operate biological processes. By combining hydrogen with carbon dioxide dissolved in this ocean of water in a chemical reaction called methanogenesis, geochemists think methane could be produced which could act as the basis of a tree of life similar to the one observed on Earth.
On Earth, this process is thought to be at the root of the tree of life, and could even be essential, critical to the origin of life on our little blue dot. Life existing on our planet requires three main ingredients, liquid water, a source of energy for metabolic processes, and specific chemical ingredients to develop and continue to thrive. This study shows Enceladus could have the right ingredients for life to exist, but planetary scientists and exobiologists are looking for evidence of the presence of sulfur and phosphorus.
Previous data shows the rocky core of this moon is similar to meteorites containing these two elements, so they’re thought to be chemically similar in nature, and scientists are looking for the same chemical ingredients of life found on Earth, primarilycarbon, nitrogen, oxygen, and of course hydrogen, phosphorus, and sulphur.
“Confirmation that the chemical energy for life exists within the ocean of a small moon of Saturn is an important milestone in our search for habitable worlds beyond Earth,” said Linda Spilker, Cassini project scientist at NASA’s Jet Propulsion Laboratory (JPL) in Pasadena, California.
Cassini detected hydrogen in plumes of gas and frozen matter spewing from Enceladus during the spacecraft’s deepest pass over its surface on October 28, 2015. This combined with previous data obtained by Cassini’s Ion and Neutral Mass Spectrometer (INMS) during earlier flybys around 2005,helped scientists determine that nearly 98 percent of the material spraying from the surface of the moon is water. The remaining two percent is thought to be around 1 percent hydrogen with some carbon dioxide, methane,ammonia and assorted unknown molecules in the mix.
Cassini has shown us two independent detections of possible water spewing from the surface of Enceladus. NASA and its partners are currently looking over proposals to send spacecraft to determineif there is an ocean of water beneath its surface by taking a sample. The Europa Life Finder (ELF)is the proposal NASA’s seriously looking at undertaking at this point, but reports indicate a few other proposals are also being discussed.We’ll provide additional information on other proposals as they’re released to media outlets.
“Although we can’t detect life, we’ve found that there’s a food source there for it. It would be like a candy store for microbes,” said Hunter Waite, lead author of the Cassini study.
Two different observations of possible plumes of water spraying from the icy surface of Saturn’s moon Enceladus provides proof hydrothermal activity is occurring beneath. Geophysicists believe hot water is combining chemically with rock and other matter at the bottom of an ocean of water underneath its icy surface to produce hydrogen gas. Hydrogen gas exobiologists think could be used as energy, food of a sort, to sustain life forms exobiologists want to meet and learn more about. A meeting that would change our place in the cosmos, the way we think about the universe, and reality.
Astronomers and researchers working with the Hubble Space Telescope in 2016 reported on an observation of a possible plume erupting from the icy surface of Europa in the same general location Hubble observed a possible plume in 2014. This location also corresponds to the unusually warm region with cracks in the icy surface observed by NASA’s Galileo spacecraft back in the 1990s.This provides evidence this phenomenon could be periodic, intermittent in this region of the moon. Mission planners are looking at this region as a possible location to obtain a sample ofwater erupting from a possible ocean of water beneath its icy surface. Watch this video on Europa.
Estimates of the sizeof this most recently observed plume indicate it rose about 62 miles (~100 kilometers) from the surface of Europa, while the plume in 2014 only reached a height of around 30 miles (50 kilometers).
“The plumes on Enceladus are associated with hotter regions, so after Hubble imaged this new plume-like feature on Europa, we looked at that location on the Galileo thermal map. We discovered that Europa’s plume candidate is sitting right on the thermal anomaly,” said William Sparks of the Space Telescope Science Institute in Baltimore, Maryland. Sparks led the Hubble plume studies in both 2014 and 2016.
One interesting thought’s the plumes and the hot spot is somehow linked. If this is the case, it could mean the vented water’s falling onto the surface of the moon, which would change the structure and chemistry of the surface grains and allow them to retain heat longer than the surrounding region. This location would be a great place to search for the ingredients of life and a possible entry point into an ocean of water beneath.
These observations by the Hubble Space Telescope and future looks enable future space missions to Europa and other ocean worlds in the solar system. Specifically, laying the groundwork for NASA’s Europa Clipper mission, which is setfor a launch sometime in the 2020s.
“If there are plumes on Europa, as we now strongly suspect, with the Europa Clipper we will be ready for them,” said Jim Green, Director of Planetary Science, at NASA Headquarters.
NASA has indicated they’re looking to identify a possible site with persistent, intermittent plume activity as a target location for a mission to Europa to explore using its powerful suite of science instruments. Another team’s currently at work on a powerful ultraviolet camera to add to the Europa Clipper that would offer data similar to that provided by the Hubble Space Telescope, while some members of the Cassini team areworking on a very sensitive, next generation INMS instrument to put on the spacecraft.
Water’s the story of life on Earth! Science has shown it played and plays the main part in the birth,evolution, and sustenance of life on Earth.
NASA’s planning on taking the human journey to the beginning of space and time to the ocean worlds of the solar system during the decades ahead. To search for the ingredients of life and even possibly simple one-celled life forms, of an unknown type. We plan on going along for the ride to have a look for ourselves and we hope to see your name on the ship manifest. We’ll save a seat for you.
Join the human journey to the beginning of space and time by taking part in NASA’s Backyard Worlds: Planet 9. Participants take part in the search for hidden worlds between Neptune and Proxima Centauri.
Looking for changes in features of hydrocarbon sands in order to better understand winds and dunes of Titan
Space news (Planetary science: the moons of Saturn; Titan)
At first glance of news, it might seem Saturn’s frozen moon Titan is similar to Earth in many ways, but the atmospheric phenomenon and surfaces detected aren’t anything like those on Earth. The clouds of this distant moon drop ethane and methane rain into lakes covering large regions. The solid surface of Titan is made primarily of solid water and its vast dune fields are composed of hydrocarbon sands.
The dark shadowy region in the Cassini image of Titan above hosts two large regions where planetary scientists detect hydrocarbon sand dunes called Aztlan (in the south, down direction) and Fensal (in the north, down direction). Planetary scientists study surface features looking for changes over time, which they use to better understand the atmospheric phenomenon.
The view above was taken at a distance of about 450,000 miles (730,000 kilometers), by Cassini’s narrow-angle camera on July 25, 2015, using a spectral filter sensitive to near-infrared light with a wavelength of 938 nanometers.
The mosaic below is composed of Cassini images taken on September 07, 2015, of the hemisphere of Titan containing the dune-filled regions Aztlan and Fensal. Planetary scientists detect small islands from 3 to 25 (5 to 40 kilometers) in size sprinkled around these regions, they believe are mainly water ice along the top, with a dark particulate material deposited by the atmosphere in the surrounding lower areas.
The larger island to the near right, called Bazaruto Facula, contains a dark crater, while several islands in Western Fensal above can be seen here. Images of a region called Shangri-La located on the opposite side of Titan, show similar island-features which appear in clusters with an east-west orientation along their long axis.
Aztlan to the south in this image appears to have far fewer small island features. Planetary scientists do detect three large islands in the western reaches of this region and a few smaller islands. The largest of the islands just right of center in the bottom left frame is 149 to 75 miles (240 by 120 kilometers) across and has been given the name of Sotra Facula.
Discover everything Cassini has discovered about Titan here.
Space news (September 29, 2015) – 30 miles above the icy surface of Saturn’s moon Enceladus –
NASA planetary scientists and astrophysicists studying seven years of Cassini images and gravitational data provided by the Cassini Solstice Mission believe they have proof positive of the existence of a global liquid ocean of water beneath the icy shell of Saturn’s moon Enceladus.
By carefully mapping craters and other surface features planetary scientists were able to precisely measure changes in the rotation of Enceladus, which indicated a slight wobble in its orbit. A slight wobble they believe is caused by Enceladus not being perfectly round and traveling faster and slower at different times and positions of its orbit around Saturn. This difference in velocity as it orbits the sixth planet from Sol, causes Saturn to gently rock the moon as it rotates on its axis, producing the slight wobble.
Planetary scientists found the only way they can account for the magnitude of the very small wobble – called a libration-of Enceladus in computer simulations, is if a global ocean of liquid water exists beneath its outer ice shell.
“This was a hard problem that required years of observations, and calculations involving a diverse collection of disciplines, but we are confident we finally got it right,” said Peter Thomas, a Cassini imaging team member at Cornell University, Ithaca, New York, and lead author of the paper.
This is in line with previous data obtained by Cassini and interpreted by planetary scientists as a fine spray of water vapor containing icy particles and basic organic molecules erupting from surface fractures near Enceladus’s southern pole region. Astrophysicists believe the global ocean their analysis indicates exists beneath the ice shell of Enceladus is the source of the fine spray and a possible habitat life could develop and survive in.
“If the surface and core were rigidly connected, the core would provide so much dead weight the wobble would be far smaller than we observe it to be,” said Matthew Tiscareno, a Cassini participating scientist at the SETI Institute, Mountain View, California, and a co-author of the paper. “This proves that there must be a global layer of liquid separating the surface from the core,” he said.
Planetary scientists are currently trying to figure out where the energy keeping the global ocean from completely freezing is coming from. At this point, they think tidal forces due to the gravity of Saturn could be producing a lot more energy than previously calculated.
“This is a major step beyond what we understood about this moon before, and it demonstrates the kind of deep-dive discoveries we can make with long-lived orbiter missions to other planets,” said co-author Carolyn Porco, Cassini imaging team lead at Space Science Institute (SSI), Boulder, Colorado, and visiting scholar at the University of California, Berkeley. “Cassini has been exemplary in this regard.”
Where’s the heat coming from?
The heat energy keeping the global ocean of Enceladus from freezing could be partly coming from geothermal sources on the bottom of the ocean. Cassini is scheduled to pass over Enceladus again on October 28, 2015, at which time it will only be about 30 miles (49 kilometers) above the surface of the moon, which is the closest the spacecraft will come to the surface. Planetary scientists want to pass through the icy spray, again, to collect more data, and hopefully, determine the reasons the global ocean isn’t frozen.
You can read and learn more about Cassini’s mission to Saturn here.
Go here to discover NASA’s mission to the stars and their future plans.
You can learn more about Saturn’s moon Enceladus here.
Stunning Saturn, with its spectacular rings composed of pieces of rock and ice ranging in size from dust grains to city blocks, and mini solar system composed of at least 53 known moons, with another nine needing confirmation
Space & Astronomy Wiki – the planets in the solar system –
Called Saturnus by the Romans and Chronos by the Greeks, Saturn was first recorded by the Assyrians in the 8th century BC, and first seen through a telescope by Galileo in 1610.
The second biggest planet in the solar system at a radius of 58,232 km, Saturn is the sixth planet from the sun, and orbits at a distance of 1.4 billion km (886 million miles) or 9.5 AU from Sol.
It takes 29 Earth-years for Saturn to orbit the sun once, which is the length ofa year on the most distant planet viewed by ancient astronomers. Spinning on it’s axis once every 10.5 hours, the length of the day and night cycle on this distant world, the seasons on Saturn are long and hard.
The least dense of all the planets, with a specific density 0.7 less than water, you wouldn’t be able to stand on the surface of Saturn.A boat composed of water would do the trick, since water would float on the surface of this planet composed primarily of helium and hydrogen.
Reachingthe surface of Saturn would be an amazing and dangerous journey, considering the average wind speed in the atmosphere is 500 meters per second (1650 feet per second) near the equator.
The first human envoy to reach Saturn was Pioneer 11 in 1979, when it flew to within 13,700 miles (22,000 km), and discovered the planet’s strong magnetic field and two previously unseen outer rings.
Space scientists matched sizes of icy particles erupting from geysers with those in Saturn’s E ring to make discovery
Space news (June 30, 2015) – 237,378 km (147,500 miles) from Saturn
NASA space scientists using images provided by the Cassini spacecraft and computer simulations have created this collage showing long, sinuous, tendril-like streams of icy particles erupting from geysers on the surface of Enceladus’s southern polar region.
Space scientists studying the images believe these tendril-like structures originate from the geysers erupting on the surface of Saturn’s moon. Tendril-like structures they link directly to icy eruptions from certain sets of geysers on Enceladus’s surface, composed mainly of ice water particles, water vapor, and simple organic compounds.
“We’ve been able to show that each unique tendril-structure can be reproduced by particular sets of geysers on the moon’s surface,” said Colin Mitchell, a Cassini imaging team associate at the Space Science Institute in Boulder, Colorado.
Space scientists also see evidence of the appearance of icy tendrils changing over time in the images provided the NASA’s Cassini spacecraft. “It became clear to us that some features disappeared from one image to the next,” said John Weiss, an imaging team associate at Saint Martin’s University in Lacey, Washington.
NASA scientists think visible changes seen in the appearance of the icy tendrils over time is due to a cycle of tidal stresses squeezing and stretching the surface of Enceladus as it orbits Saturn. They also think that as tidal stresses increase the width of the erupting fractures on the surface expands, resulting in an increase in the icy eruptions observed.
Using this model space scientists using the Cassini spacecraft and other assets will now test their ideas and theories on the reasons for the changing appearance of icy tendrils erupting from cracks on the surface of Enceladus into Saturn’s E ring.
There is even more that can be extracted from the images, the scientists say. “As the supply lanes for Saturn’s E ring, the tendrils give us a way to ascertain how much mass is leaving Enceladus and making its way into Saturn orbit,” said Carolyn Porco, team leader for the imaging experiment and a coauthor on the paper. “So, another important step is to determine how much mass is involved, and thus, estimate how much longer the moon’s subsurface ocean may last.” An estimate of the lifetime of the ocean is important in understanding the evolution of Enceladus over long timescales.
The icy waters of Enceladus could contain the ingredients necessary for life to exist and space scientists are keen to have a closer look at this distant moon in the future. With icy plumes erupting into Saturn’s E-ring containing complex organic compounds, and tidal forces heating the surface of Enceladus, NASA scientists think this moon is one of the best and most likely places to search for extraterrestrial life in the solar system.
The mission of Cassini has been extended through to September 2017, so space scientists can take a closer look at Enceladus, Titan and the rings of Saturn. Next, on Cassini’s itinerary is a flyby of Titan on July 7, 2015, when it will be slightly less than 11, 000 km (7,000 miles) from the moon.
For more information on NASA’s Cassini Solstice Mission check here.
Methane clouds over northern seas could signal arrival of summer storms
Space news (the solar system: Saturn; Titan) – looking for evidence of clouds moving over surface of Saturn’s moon Titan –
Planetary space scientists have been looking for evidence of clouds moving over the northern hydrocarbon seas of Saturn’s moon Titan for awhile. Their planetary models of Titan predicted the movement of clouds over the northern seas, which should signal the arrival of summer storms. Near the end of July, they were provided with the proof they require in the form of images of methane clouds moving at 7 to 10 mph across the sky above the hydrocarbon seas of Titan’s northern sea Ligeia Mare. You can watch a movie showing the movement of clouds over the northern seas of Titan here.
“We’re eager to find out if the clouds’ appearance signals the beginning of summer weather patterns, or if it is an isolated occurrence,” said Elizabeth Turtle, a Cassini imaging team associate at the Johns Hopkins University Applied Physics Lab in Laurel, Maryland. “Also, how are the clouds related to the seas? Did Cassini just happen to catch them over the seas, or do they form preferentially?”
Work continues for the team
Planetary scientists will continue to watch and study seasonal changes on Saturn’s moon Titan in order to learn more about the weather systems on other worlds and our own. This will be a job requiring patience, because a year on Titan is equivalent to 30 years on Earth, and each season lasts around seven years.
You can find additional information on NASA’s Cassini Solstice Space Mission here.
You can find more information on the Cassini Orbiter Space here.
Analysis of Cassini data identifies 101 distinct icy geysers erupting on surface of Enceladus
Space news – Enceladus, Saturn (Sept 22, 2014) –
Planetary space scientists looking at information obtained by NASA’s Cassini spacecraft of the south polar region of Saturn’s moon Enceladus over a seven-year study have viewed 101 watery-geysers on the surface. This suggests to scientists it’s possible for liquid from the underground sea believed to be under the moon’s icy exterior to reach the surface and erupt as a spray of small, icy particles.
NASA’s Cassini spacecraft first saw possible geysers of water vapor erupting from the icy surface of Enceladus almost a decade ago. At this time, tiger stripe fractures could be seen on the surface, and scientists suspected they might have something to do with the geysers they could see. It took until now to confirm, through the seven-year study just completed, the 101 geysers are in fact erupting from the tiger stripe fractures. They also discovered individual geysers originate from small hot spots seen in images collected using Cassini’s temperature-sensing instruments in 2010.
“Once we had these results in hand we knew right away heat was not causing the geysers, but vice versa,” said Carolyn Porco, leader of the Cassini imaging team from the Space Science Institute in Boulder, Colorado, and lead author of the first paper. “It also told us the geysers are not a near-surface phenomenon but have much deeper roots.”
Next for scientists
Taking a closer look at data concerning the gravity field around Enceladus, planetary space scientists concluded the only plausible source of the liquid erupting from the geysers is the sea beneath the icy exterior of the moon. Computer simulations also show narrow passages to the inner sea could stay open completely to the surface if filled with liquidwater.
Additional information on NASA’s Cassini space mission can be found here.
Links to additional information, images and animations can be found here.