Solar System News (miscellaneous articles)

[Jim K Global Moderator]

Cassini Update:

 

Orbit 289 - August 17 - August 23 (Completed)

• Cassini has less than a month before the mission ends, with just four orbits of Saturn remaining.
• During this orbit, Cassini’s Ultraviolet Imaging Spectrograph (UVIS)observes Saturn’s northern aurora.
• The spacecraft’s Composite Infrared Spectrometer (CIRS) observes temperatures in Saturn’s south polar vortex.
• Cassini’s Visible and Infrared Mapping Spectrometer (VIMS) stares at Saturn’s south polar auroral region to produce a mosaic.
• This is the second of five orbits in which Cassini’s elliptical orbit carries it so low that the spacecraft passes briefly through Saturn’s atmosphere. Cassini’s reaction control thrusters are at the ready to correct the spacecraft’s orientation in case Saturn’s atmosphere pushes on the spacecraft hard enough to cause any rotation.

Cassini gazes across the icy rings of Saturn toward the icy moon Tethys, whose night side is illuminated by Saturn shine, or sunlight reflected by the planet

 

 

 

Orbit 290 - August 23 - August 30 (Current)

• Cassini has just three orbits of Saturn remaining before the mission ends.
• During this orbit Cassini’s Composite Infrared Spectrometer (CIRS)maps Saturn’s northern hemisphere to study temperatures in the upper troposphere and the Visible and Infrared Mapping Spectrometer (VIMS) creates a map of Saturn’s equatorial region. The CIRS instrument also performs its final Saturn limb observation of the mission.
• The spacecraft uses its RADAR instrument in active mode to study Saturn’s atmosphere.
• This is the third of five orbits in which Cassini’s elliptical orbit carries it so low that the spacecraft passes briefly through Saturn’s atmosphere. Cassini’s reaction control thrusters are at the ready to correct the spacecraft’s orientation in case Saturn’s atmosphere pushes on the spacecraft hard enough to cause any rotation. This is the deepest Cassini dips into Saturn’s atmosphere during the “Final Five” orbits.
• During the period in which the spacecraft is nearest Saturn, Cassini’s Ion and Neutral Mass Spectrometer (INMS) performs its second session directly sampling Saturn’s upper atmosphere. The instrument measures densities of different species of molecular hydrogen, helium and a variety of ions in the immediate vicinity of the spacecraft.

 

 

Orbit 291 - August 30 - September 5 (future)

• Cassini has just two orbits of Saturn remaining before the mission ends.
• During this orbit, Cassini’s imaging cameras, the Imaging Science Subsystem (ISS), observes haze in Titan’s atmosphere, and the spacecraft’s Ultraviolet Imaging Spectrograph (UVIS) and Visible and Infrared Mapping Spectrometer (VIMS) instruments observe Saturn’s sunlit north polar auroral region.
• The VIMS instrument and Cassini’s Composite Infrared Spectrometer (CIRS) work together to study Saturn’s atmosphere.
• This is also the fourth of five orbits in which Cassini’s elliptical orbitcarries it so low that the spacecraft passes briefly through Saturn’s atmosphere. Cassini’s reaction control thrusters are at the ready to correct the spacecraft’s orientation in case Saturn’s atmosphere pushes on the spacecraft hard enough to cause any rotation.
• During the period in which the spacecraft is nearest Saturn, Cassini’s Ion and Neutral Mass Spectrometer (INMS) performs its third session directly sampling of Saturn’s upper atmosphere. The instrument measures densities of different species of molecular hydrogen, helium and a variety of ions in the immediate vicinity of the spacecraft.

Source: JPL

 

Less than 19 days before Cassini's mission is over.  

[Jim K Global Moderator]

Latest on Cassini....about 8 days remaining before end of mission.

 

IN PROGRESS: Orbit 292 - September 5 - 12

 

• This is Cassini’s final full orbit of Saturn before the mission ends.
• During this orbit, Cassini’s Composite Infrared Spectrometer (CIRS) and Visible and Infrared Mapping Spectrometer (VIMS) instruments work together to determine the abundance of helium in Saturn’s atmosphere.
• This is the fifth of five orbits in which Cassini’s elliptical orbit carries it so low that the spacecraft passes briefly through Saturn’s atmosphere. Cassini’s reaction control thrusters are at the ready to correct the spacecraft’s orientation in case Saturn’s atmosphere pushes on the spacecraft hard enough to cause any rotation.
• During the period in which the spacecraft is nearest Saturn, Cassini’s Ion and Neutral Mass Spectrometer (INMS) performs its fourth session directly sampling Saturn’s upper atmosphere. The instrument measures densities of different species of molecular hydrogen, helium and a variety of ions in the immediate vicinity of the spacecraft.
• The spacecraft’s RADAR and Imaging Science Subsystem (ISS) instruments also operate during the INMS observation, with RADAR continuing its study of ammonia in Saturn’s atmosphere and the ISS instrument capturing an iconic image of the rings seen looking outward from Saturn.
• At the end of this orbit, Cassini makes a distant flyby of the Mercury-size moon Titan, whose gravity alters the spacecraft’s trajectory one final time. This gravitational nudge, which the team calls “the goodbye kiss,” ensures that the spacecraft is disposed of in a controlled manner. Instead of passing safely into and out of Saturn’s outermost atmosphere on the next orbit, Cassini will instead dip so deeply into the atmosphere that the spacecraft will burn up like a meteor.

 

 

This view from NASA's Cassini spacecraft shows a wave structure in Saturn's rings known as the Janus 2:1 spiral density wave. Resulting from the same process that creates spiral galaxies, spiral density waves in Saturn’s rings are much more tightly wound. In this case, every second wave crest is actually the same spiral arm which has encircled the entire planet multiple times.

This is the only major density wave visible in Saturn's B ring. Most of the B ring is characterized by structures that dominate the areas where density waves might otherwise occur, but this innermost portion of the B ring is different.

The radius from Saturn at which the wave originates (toward lower-right in this image) is 59,796 miles (96,233 kilometers) from the planet. At this location, ring particles orbit Saturn twice for every time the moon Janus orbits once, creating an orbital resonance. The wave propagates outward from the resonance (and away from Saturn), toward upper-left in this view. For reasons researchers do not entirely understand, damping of waves by larger ring structures is very weak at this location, so this wave is seen ringing for hundreds of bright wave crests, unlike density waves in Saturn's A ring. 

The image gives the illusion that the ring plane is tilted away from the camera toward upper-left, but this is not the case. Because of the mechanics of how this kind of wave propagates, the wavelength decreases with distance from the resonance. Thus, the upper-left of the image is just as close to the camera as the lower-right, while the wavelength of the density wave is simply shorter. 

This wave is remarkable because Janus, the moon that generates it, is in a strange orbital configuration. Janus and Epimetheus (see "Cruising Past Janus") share practically the same orbit and trade places every four years. Every time one of those orbit swaps takes place, the ring at this location responds, spawning a new crest in the wave. The distance between any pair of crests corresponds to four years’ worth of the wave propagating downstream from the resonance, which means the wave seen here encodes many decades’ worth of the orbital history of Janus and Epimetheus. According to this interpretation, the part of the wave at the very upper-left of this image corresponds to the positions of Janus and Epimetheus around the time of the Voyager flybys in 1980 and 1981, which is the time at which Janus and Epimetheus were first proven to be two distinct objects (they were first observed in 1966). 

Epimetheus also generates waves at this location, but they are swamped by the waves from Janus, since Janus is the larger of the two moons. 

This image was taken on June 4, 2017, with the Cassini spacecraft narrow-angle camera. The image was acquired on the sunlit side of the rings from a distance of 47,000 miles (76,000 kilometers) away from the area pictured. The image scale is 1,730 feet (530 meters) per pixel. The phase angle, or sun-ring-spacecraft angle, is 90 degrees.

NASA

 

 

[Jim K Global Moderator]

This is the end .... The Grand Finale 

 

Orbit 293 - The Final Plunge - September 12 - 15

 

• During this partial orbit, when Cassini is three and half hours from its expected end of mission, data from the spacecraft’s Composite Infrared Spectrometer (CIRS), Ultraviolet Imaging Spectrograph (UVIS), and magnetospheric and plasma science instruments are transmitted to Earth in nearly real time, just seconds after each observation is made. Cassini usually holds onto those data for hours or days before turning its high-gain antenna toward Earth to transmit them.
• Unlike the preceding orbits, where the Cassini’s lowest altitudes were chosen to avoid tumbling, the spacecraft trajectory on this orbit intentionally continues all the way into Saturn.
• Cassini continues transmitting as long as possible until the force of Saturn’s atmosphere overpowers the spacecraft’s thrusters and Cassini can no longer point its antenna precisely enough to maintain contact with Earth.
• When the spacecraft’s signal is lost, the Cassini mission comes to an end.

 

 

 

Also, NASA has released an e-book (free obviously) which contains about a 100 pages of Saturn (and the moons) goodness.  It is available in various formats (iBook, Kindle, other epub and PDF).  I ran through the first 20 pages or so and it is very nice.  Highly recommended.

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This free NASA e-Book celebrates Saturn as seen through the eyes of the Cassini spacecraft. 

 

The Cassini-Huygens mission has revolutionized our knowledge of the Saturn system and revealed surprising places in the solar system where life could potentially gain a foothold—bodies we call ocean worlds.

 

Since its arrival in 2004, Cassini–Huygens has been nothing short of a discovery machine, captivating us with data and images never before obtained with such detail and clarity. Cassini taught us that Saturn is a far cry from a tranquil lone planet with delicate rings. Now, we know more about Saturn’s chaotic, active, and powerful rings, and the storms that rage beneath. Images and data from Saturn’s moons Titan and Enceladus hint at the possibility of life never before suspected. The rings of Saturn, its moons, and the planet itself offer irresistible and inexhaustible subjects for intense study. As the Cassini mission comes to a dramatic end with a fateful plunge into Saturn on Sept. 15, 2017, scientists are already dreaming of going back for further study.   

 

Over a period of 13 years, Cassini has captured about 450,000 spectacular images within the Saturn system, providing new views of the “lord of the rings” and a plethora of iconic images. To honor the art and science of Cassini, this book was developed collaboratively by a team from NASA’s Planetary Science Division (PSD), NASA’s Jet Propulsion Laboratory (JPL), and the Lunar and Planetary Institute (LPI). While these images represent the tip of the iceberg—each telling a story about Saturn and its mysterious moons—our hope is that the mission will inspire future artists and explorers. The sheer beauty of these images is surpassed only by the science and discoveries they represent.

 

JPL-NASA

 

 

 

NASA JPL will livestream Mission Control during Cassini's End Mission.  http://youtube.com/nasajpl/  September 15 @ 7 AM ET

 

(original image here)

 

 

[Jim K Global Moderator]

Cassini is now one with Saturn.

 

 

End of mission.

 

 

 

[DocM]

Wow, some sci-fi special effects artists need to go to school on this image.

 

 

Edited September 15, 2017 by DocM

[mudslag]

https://streamable.com/5vlrv

[DocM]

 

[Jim K Global Moderator]

On 10/1/2016 at 11:17 PM, Draggendrop said:

Rosetta’s last photo, taken 51 meters above the surface – Credit: ESA/Rosetta/MPS for OSIRIS Team MPS/UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA

 

 

Oh where is our Draggendrop?

 

Anyway ... ESA has reconstructed one last image before Rosetta crashed into 67P from a few telemetry packets on their server.  Closest image to the surface ... and the last.

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Unexpected Surprise: A Final Image From Rosetta

 

28 September 2017:  Scientists analysing the final telemetry sent by Rosetta immediately before it shut down on the surface of the comet last year have reconstructed one last image of its touchdown site.

 

After more than 12 years in space, and two years following Comet 67P/Churyumov–Gerasimenko as they orbited the Sun, Rosetta’s historic mission concluded on 30 September with the spacecraft descending onto the comet in a region hosting several ancient pits.

 

It returned a wealth of detailed images and scientific data on the comet’s gas, dust and plasma as it drew closer to the surface.

 

But there was one last surprise in store for the camera team, who managed to reconstruct the final telemetry packets into a sharp image. 

 

“The last complete image transmitted from Rosetta was the final one that we saw arriving back on Earth in one piece moments before the touchdown at Sais,” says Holger Sierks, principal investigator for the OSIRIS camera at the Max Planck Institute for Solar System Research in Göttingen, Germany.

 

“Later, we found a few telemetry packets on our server and thought, wow, that could be another image.”

 

During operations, images were split into telemetry packets aboard Rosetta before they were transmitted to Earth. In the case of the last images taken before touchdown, the image data, corresponding to 23 048 bytes per image, were split into six packets.

 

For the very last image the transmission was interrupted after three full packets were received, with 12 228 bytes received in total, or just over half of a complete image. This was not recognized as an image by the automatic processing software, but the engineers in Göttingen could make sense of these data fragments to reconstruct the image.

 

Owing to the onboard compression software, the data were not sent pixel-by-pixel but rather layer-by-layer, which gives an increasing level of detail with each layer.

 

The 53% of transmitted data therefore represents an image with an effective compression ratio of 1:38 compared to the anticipated compression ratio of 1:20, meaning some of the finer detail was lost.

 

That is, it gets a lot blurrier as you zoom in compared with a full-quality image. This can be likened to compressing an image to send via email, versus an uncompressed version that you would print out and hang on your wall.

 

The camera was not designed to be used below a few hundred metres from the surface but a sharper image could be achieved using the camera in a special configuration: while the camera was designed to be operated with a colour filter in the optical beam, this was removed for the last images. This would have resulted in the images being blurred for the normal imaging scenario above 300 m, but they came into focus at a ‘sweet spot’ of 15 m distance.

 

Approaching 15 m therefore improved the focus and thus level of detail, as can be seen in the reconstructed image taken from an altitude of 17.9–21.0 m and corresponding to a 1 x 1 m square region on the surface.

 

In the meantime, the altitude of the previously published last image has been revised to 23.3–26.2 m. The uncertainty arises from the exact method of altitude calculation and the comet shape model used.

 

The sequence of images progressively reveals more and more detail of the boulder-strewn surface, providing a lasting impression of Rosetta’s touchdown site.

 

Last Image:

 

In context to others:

 

 

Article at the European Space Agency

[DocM]

Via Unibersity of Michigan News

 

http://ns.umich.edu/new/releases/25192-thruster-for-mars-mission-breaks-records

 

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Thruster for Mars Mission Breaks Records

 

ANN ARBOR, Mich. (University of Michigan PR) — An advanced space engine in the running to propel humans to Mars has broken the records for operating current, power and thrust for a device of its kind, known as a Hall thruster.

The development of the thruster was led by Alec Gallimore, University of Michigan professor of aerospace engineering and the Robert J. Vlasic Dean of Engineering.

Hall thrusters offer exceptionally efficient plasma-based spacecraft propulsion by accelerating small amounts of propellant very quickly using electric and magnetic fields. They can achieve top speeds with a tiny fraction of the fuel required in a chemical rocket.

“Mars missions are just on the horizon, and we already know that Hall thrusters work well in space,” Gallimore said. “They can be optimized either for carrying equipment with minimal energy and propellant over the course of a year or so, or for speed—carrying the crew to Mars much more quickly.”

The challenge is to make them larger and more powerful. The X3, a Hall thruster designed by researchers at U-M, NASA and the U.S. Air Force, shattered the previous thrust record set by a Hall thruster, coming in at 5.4 newtons of force compared with 3.3 newtons. The improvement in thrust is especially important for crewed mission—it means faster acceleration and shorter travel times. The X3 also more than doubled the operating current record (250 amperes vs. 112 amperes) and ran at a slightly higher power (102 kilowatts vs. 98 kilowatts).

The X3 is one of three prototype “Mars engines” to be turned into a full propulsion system with funding from NASA. Scott Hall, a doctoral student in aerospace engineering at U-M, carried out the tests at the NASA Glenn Research Center in Cleveland, along with Hani Kamhawi, a NASA Glenn research scientist who has been heavily involved in the development of the X3. The experiments were the culmination of more than five years of building, testing and improving the thruster.

NASA Glenn, which specializes in solar electric propulsion, is currently home to the only vacuum chamber in the U.S. that can handle the X3 thruster. The thruster produces so much exhaust that vacuum pumps at other chambers can’t keep up. Then, xenon that has been shot out the back of the engine can drift back into the plasma plume, muddying the results. But as of January 2018, an upgrade of the vacuum chamber in Gallimore’s lab will enable X3 testing right at U-M.

For now, the X3 team snagged a test window from late July through August this year, starting with four weeks to set up the thrust stand, mount the thruster and connect the thruster with xenon and electrical power supplies. Hall had built a custom thrust stand to bear the X3’s 500-pound weight and withstand its force, as existing stands would collapse under it. Throughout the process, Hall and Kamhawi were supported by NASA researchers, engineers and technicians.

“The big moment is when you close the door and pump down the chamber,” Hall said.

After the 20 hours of pumping to achieve a space-like vacuum, Hall and Kamhawi spent 12-hour days testing the X3.

Even small breakages feel like big problems when it takes days to gradually bring air back into the chamber, get in to make the repair and pump the air back out again. But in spite of the challenges, Hall and Kamhawi brought the X3 up to its record-breaking power, current and thrust over the 25 days of testing.

Looking ahead, the X3 will at last be integrated with the power supplies under development by Aerojet Rocketdyne, a rocket and missile propulsion manufacturer and lead on the propulsion system grant from NASA. In spring 2018, Hall expects to be back at NASA Glenn running a 100-hour test of the X3 with Aerojet Rocketdyne’s power processing system.

The project is funded through NASA’s Next Space Technologies for Exploration Partnership, which supports not just propulsion systems but also habitat systems and in-space manufacturing.

Gallimore is also the Richard F. and Eleanor A. Towner Professor, an Arthur F. Thurnau Professor and a professor of applied physics. Kamhawi is also Hall’s NASA mentor as part of the NASA Space Technology Research Fellowship. The $1 million upgrade of the test facility in Gallimore’s lab is funded in part by the Air Force Office of Scientific Research, with additional support from NASA’s Jet Propulsion Laboratory and U-M.

 

 

Edited October 25, 2017 by DocM

[Jim K Global Moderator]

...a first (well a first observation)....

 

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Small Asteroid or Comet 'Visits' from Beyond the Solar System

 

A small, recently discovered asteroid -- or perhaps a comet -- appears to have originated from outside the solar system, coming from somewhere else in our galaxy. If so, it would be the first "interstellar object" to be observed and confirmed by astronomers.

 

This unusual object – for now designated A/2017 U1 – is less than a quarter-mile (400 meters) in diameter and is moving remarkably fast. Astronomers are urgently working to point telescopes around the world and in space at this notable object. Once these data are obtained and analyzed, astronomers may know more about the origin and possibly composition of the object.

 

A/2017 U1 was discovered Oct. 19 by the University of Hawaii's Pan-STARRS 1 telescope on Haleakala, Hawaii, during the course of its nightly search for near-Earth objects for NASA. Rob Weryk, a postdoctoral researcher at the University of Hawaii Institute for Astronomy (IfA), was first to identify the moving object and submit it to the Minor Planet Center. Weryk subsequently searched the Pan-STARRS image archive and found it also was in images taken the previous night, but was not initially identified by the moving object processing.

 

Weryk immediately realized this was an unusual object. "Its motion could not be explained using either a normal solar system asteroid or comet orbit," he said. Weryk contacted IfA graduate Marco Micheli, who had the same realization using his own follow-up images taken at the European Space Agency's telescope on Tenerife in the Canary Islands. But with the combined data, everything made sense. Said Weryk, "This object came from outside our solar system."  

 

"This is the most extreme orbit I have ever seen," said Davide Farnocchia, a scientist at NASA's Center for Near-Earth Object Studies (CNEOS) at the agency's Jet Propulsion Laboratory in Pasadena, California. "It is going extremely fast and on such a trajectory that we can say with confidence that this object is on its way out of the solar system and not coming back."

 

The CNEOS team plotted the object's current trajectory and even looked into its future. A/2017 U1 came from the direction of the constellation Lyra, cruising through interstellar space at a brisk clip of 15.8 miles (25.5 kilometers) per second.

 

The object approached our solar system from almost directly "above" the ecliptic, the approximate plane in space where the planets and most asteroids orbit the Sun, so it did not have any close encounters with the eight major planets during its plunge toward the Sun. On Sept. 2, the small body crossed under the ecliptic plane just inside of Mercury's orbit and then made its closest approach to the Sun on Sept. 9. Pulled by the Sun's gravity, the object made a hairpin turn under our solar system, passing under Earth's orbit on Oct. 14 at a distance of about 15 million miles (24 million kilometers) -- about 60 times the distance to the Moon. It has now shot back up above the plane of the planets and, travelling at 27 miles per second (44 kilometers per second) with respect to the Sun, the object is speeding toward the constellation Pegasus.   

"We have long suspected that these objects should exist, because during the process of planet formation a lot of material should be ejected from planetary systems. What's most surprising is that we've never seen interstellar objects pass through before," said Karen Meech, an astronomer at the IfA specializing in small bodies and their connection to solar system formation.

 

The small body has been assigned the temporary designation A/2017 U1 by the Minor Planet Center (MPC) in Cambridge, Massachusetts, where all observations on small bodies in our solar system -- and now those just passing through -- are collected. Said MPC Director Matt Holman, "This kind of discovery demonstrates the great scientific value of continual wide-field surveys of the sky, coupled with intensive follow-up observations, to find things we wouldn't otherwise know are there."

 

Since this is the first object of its type ever discovered, rules for naming this type of object will need to be established by the International Astronomical Union.

 

"We have been waiting for this day for decades," said CNEOS Manager Paul Chodas. "It's long been theorized that such objects exist -- asteroids or comets moving around between the stars and occasionally passing through our solar system -- but this is the first such detection. So far, everything indicates this is likely an interstellar object, but more data would help to confirm it."

 

NASA

97K mph (with respect to the sun) ... that is booking.

 

__________

 

 

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Dawn Finds Possible Ancient Ocean Remnants at Ceres

 

Minerals containing water are widespread on Ceres, suggesting the dwarf planet may have had a global ocean in the past. What became of that ocean? Could Ceres still have liquid today? Two new studies from NASA's Dawn mission shed light on these questions.

 

The Dawn team found that Ceres' crust is a mixture of ice, salts and hydrated materials that were subjected to past and possibly recent geologic activity, and that this crust represents most of that ancient ocean. The second study builds off the first and suggests there is a softer, easily deformable layer beneath Ceres' rigid surface crust, which could be the signature of residual liquid left over from the ocean, too.

 

"More and more, we are learning that Ceres is a complex, dynamic world that may have hosted a lot of liquid water in the past, and may still have some underground," said Julie Castillo-Rogez, Dawn project scientist and co-author of the studies, based at NASA's Jet Propulsion Laboratory, Pasadena, California.

 

What's inside Ceres? Gravity will tell.

 

Landing on Ceres to investigate its interior would be technically challenging and would risk contaminating the dwarf planet. Instead, scientists use Dawn's observations in orbit to measure Ceres' gravity, in order to estimate its composition and interior structure.

 

The first of the two studies, led by Anton Ermakov, a postdoctoral researcher at JPL, used shape and gravity data measurements from the Dawn mission to determine the internal structure and composition of Ceres. The measurements came from observing the spacecraft's motions with NASA's Deep Space Network to track small changes in the spacecraft's orbit. This study is published in the Journal of Geophysical Research: Planets.

 

Ermakov and his colleagues' research supports the possibility that Ceres is geologically active -- if not now, then it may have been in the recent past. Three craters -- Occator, Kerwan and Yalode -- and Ceres' solitary tall mountain, Ahuna Mons, are all associated with "gravity anomalies." This means discrepancies between the scientists' models of Ceres' gravity and what Dawn observed in these four locations can be associated with subsurface structures.

 

"Ceres has an abundance of gravity anomalies associated with outstanding geologic features," Ermakov said. In the cases of Ahuna Mons and Occator, the anomalies can be used to better understand the origin of these features, which are believed to be different expressions of cryovolcanism.

 

The study found the crust's density to be relatively low, closer to that of ice than rocks. However, a study by Dawn guest investigator Michael Bland of the U.S. Geological Survey indicated that ice is too soft to be the dominant component of Ceres' strong crust. So, how can Ceres' crust be as light as ice in terms of density, but simultaneously much stronger? To answer this question, another team modeled how Ceres' surface evolved with time.

 

A 'Fossil' Ocean at Ceres

 

The second study, led by Roger Fu at Harvard University in Cambridge, Massachusetts, investigated the strength and composition of Ceres' crust and deeper interior by studying the dwarf planet's topography. This study is published in the journal Earth and Planetary Science Letters

 

By studying how topography evolves on a planetary body, scientists can understand the composition of its interior. A strong, rock-dominated crust can remain unchanged over the 4.5-billion-year-old age of the solar system, while a weak crust rich in ices and salts would deform over that time.

 

By modeling how Ceres' crust flows, Fu and colleagues found it is likely a mixture of ice, salts, rock and an additional component believed to be clathrate hydrate. A clathrate hydrate is a cage of water molecules surrounding a gas molecule. This structure is 100 to 1,000 times stronger than water ice, despite having nearly the same density.

 

The researchers believe Ceres once had more pronounced surface features, but they have smoothed out over time. This type of flattening of mountains and valleys requires a high-strength crust resting on a more deformable layer, which Fu and colleagues interpret to contain a little bit of liquid.

 

The team thinks most of Ceres' ancient ocean is now frozen and bound up in the crust, remaining in the form of ice, clathrate hydrates and salts. It has mostly been that way for more than 4 billion years. But if there is residual liquid underneath, that ocean is not yet entirely frozen. This is consistent with several thermal evolution models of Ceres published prior to Dawn's arrival there, supporting the idea that Ceres' deeper interior contains liquid left over from its ancient ocean.

 

NASA

 

 

 

________

 

 

[Unobscured Vision]

The results are in, and they're very, very good. I suppose it was just a matter of time ...  Now we're directly looking at it.

 

Huge Subsurface Water Reserves Found All Over Mars

Article link | National Geographic website

Awww yeah.  

[Unobscured Vision]

I've been looking at the above image for a few minutes ... fairly consistent water level(s) there. I betcha we can get an average global surface water height now.  Also seeing where the shorelines were when the climate stabilized at various points as the atmosphere was fizzling out.

[DocM]

More,

 

 

[Unobscured Vision]

And best of all, candidate sites for landings just got a whole lot more interesting. And narrowed-down, I think.  

[DocM]

The first machines there should be  remote controllable roadheaders with a selection of cutter heads & spare cutters. A real Jack of all trades,

 

Trenching

Mining

Tunneling

Chamber shaping

Subsurface road leveling

Etc.

 

Faster than a TBM and they spit the cuttings out their rear for other vehicles to remove.

[Unobscured Vision]

Ironic ... and here I've been taking Geology and Mining Science modules in addition to my regular classload...

 

(Sorry, I really wanna go! )

[Unobscured Vision]

A follow-up to the recent finding of immediate-surface ice deposits on Mars, this time from Phys.org. Worth a read, and has lots of specific info. Literally all that's needed is a shovel, a pickaxe and a wheelbarrow to haul the ice away.  

 

Phys.org article link

A cross-section of a thick sheet of underground ice is exposed at the steep slope (or scarp) that appears bright blue in this enhanced-color view from the High Resolution Imaging Science Experiment (HiRISE) camera on NASA's Mars Reconnaissance Orbiter. The view covers an area about 550 yards (500 meters) wide. Figure 1 includes a 100-meter (109-yard) scale bar. North is toward the top. The upper third of the image shows level ground that is about 140 yards (130 meters) higher in elevation than the ground in the bottom third. In between, the scarp descends sharply, exposing about 260 vertical feet (80 vertical meters) of water ice. Color is exaggerated to make differences in surface materials easier to see. The presence of exposed water ice at this site was confirmed by observation with the same orbiter's Compact Reconnaissance Imaging Spectrometer for Mars (CRISM). Credit: NASA/JPL-Caltech/UA/USGS

 

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Researchers using NASA's Mars Reconnaissance Orbiter (MRO) have found eight sites where thick deposits of ice beneath Mars' surface are exposed in faces of eroding slopes. These eight scarps, with slopes as steep as 55 degrees, reveal new information about the internal layered structure of previously detected underground ice sheets in Mars' middle latitudes.

 

The ice was likely deposited as snow long ago. The deposits are exposed in cross section as relatively pure water ice, capped by a layer one to two yards (or meters) thick of ice-cemented rock and dust. They hold clues about Mars' climate history. They also may make frozen water more accessible than previously thought to future robotic or human exploration missions. Researchers who located and studied the scarp sites with the High Resolution Imaging Science Experiment (HiRISE) camera on MRO reported the findings today in the journal Science. The sites are in both northern and southern hemispheres of Mars, at latitudes from about 55 to 58 degrees, equivalent on Earth to Scotland or the tip of South America.

(I strongly suggest reading the rest of the article by following the link above. It's worth the read.)

[Unobscured Vision]

It just occurred to me that the landing sites on missions are going to really want to take advantage of these exposed glacier faces. If we can get away with not needing to bother with bringing H2O with us and/or using Sabatier conversion to make H2O ... that frees up a LOT of, well, everything. It's less of a priority since it's right there on Mars, in QUITE abundant supply and it appears to be clean.

 

Yeah ... that'll do.  

[DocM]

 

 

Roadheaders rule...

[Beittil]

Yes yes, we know... You are a fan of road headers

[LOC Veteran]

It occurs to me, that its awesome they found water ice underground like that and how it might make things much easier for us to go to Mars. But, isn't anyone thinking that the H2O that is there, might not be ok for Humans to ingest? For whatever reason, add in anything from contamination of foreign contaminants (I mean we have been to the planet for years now who knows what could have survived the trip and might have mutated in the Sunlight on Mars) to just "its dirty water ice" etc. Not to mention, what if the water contains alien lifeforms that spread to everyone and then the crew have to nuke the base to protect Earth from infection! (Doctor Who says hi)

[Unobscured Vision]

Then we take water purifiers. Problem solved.

[LOC Veteran]

What if its not that simple though?

[devn00b]

Boil the water, collect steam. Add some minerals back to said steam, and you have drinking water. Can then even filter the steam if you are not sure. 

[Unobscured Vision]

8 minutes ago, LOC said:

What if its not that simple though?

Nothing gets past the filtration techniques that NASA uses. NOTHING. Those techniques put everything else to shame ... contaminants like urea, etc are it's specialty. The stuff at Mars will be no problem.

 

Only deal with the NASA gear is that it's a bit slow, relatively speaking, but the gear has improved as time has gone on. They're using it at the ISS now. For Mars, they'll have plenty of H2O supply to bring to the recycler (where in the case of the ISS they have to bring it to-station). That's part of the process.

 

Now that Sabatier Conversion is a thing for H2O as much as O2, the game has changed. They're still working on making the system automated though. Not quite there yet.