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Solar System News (miscellaneous articles)

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Unobscured Vision    2,666
Just now, Draggendrop said:

A few posts back, a post was made showing this...

 

Namib Dune, Gale Crater, Mars

 

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Namib Dune   NASA

 

This dune is approximately 20 ft at the face.  To the left and on another bank system we have this...

 

23982942340_55e767d1a1_o.jpg

same area around the corner, approximate 10 ft face, darker composition

 

here is a paper...

THE BAGNOLD DUNES AT GALE CRATER – A KEY TO READING THE GEOLOGIC RECORD OF
MOUNT SHARP

http://www.hou.usra.edu/meetings/lpsc2015/pdf/1634.pdf

 

From this and Nasa/JPL-Caltech articles, it appears Mars has two dune types. One type composed of larger granular material, which now, does not move due to losses of atmosphere, and the other type, composed of finer particulates. The outer dust layers are usually lighter colored and base material appears to be mostly darker compositions. They are composed of mafic mineral sands, such as pyroxenes. The light granular grains can be as small as "smoke dust" and the absence of water has maintained structure and ensured continued erosion from environmental forces.

 

In a nutshell...This stuff is going to be great for regolith construction techniques, even 3D printing.

 

This dark dunes reminds one of several places on earth with stained or volcanic granular dunes such as Hawaii...

 

black_sand_beach.jpg

This is not Mars........yet!

 

:)

But it will be. :shifty: See http://motherboard.vice.com/read/a-step-by-step-guide-to-terraforming-mars for a synopsis -- and it's the "Elon Musk" way. There's even a short video.

 

More reference material below.

 

https://en.wikipedia.org/wiki/Terraforming_of_Mars

http://science.howstuffworks.com/terraforming.htm

http://www.popularmechanics.com/space/moon-mars/a15410/terraform-mars-with-microbes/

 

Food for the brain. :yes: 

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Draggendrop    5,747

^ Just read them, neat concepts.....but, sadly far away yet. I think we'll do fine there, once boots on the ground. It will take time, but the natural resources are phenomenal. IMHO, we need manufacturing of in situ resources, into the structures, chemicals and gases required to sustain a colony...and we can do it now...just need the will.

 

:)

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Draggendrop    5,747

Probing the Mysterious Glacial Flow on Pluto's Frozen 'Heart'

 

icy_plains-1024x744.thumb.jpg.ad21fe0d11

A nearly top-down view of Pluto's icy plains, showing dark lanes reminiscent of glacial moraines. 

 

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Written 45 years ago, these words are more appropriate today than Moore could have ever imagined. Greetings, I'm Dr. Orkan Umurhan, a scientist on New Horizons' Geology and Geophysics Investigation (GGI) Team.

 

Pluto's surface geology alone - from the bladed terrain of Tartarus Dorsa to the mysterious dark mound of Morgoth Macula (just to mention a few informally named features with perplexing geologies) - continues to stump all of us on the New Horizons Geology and Geophysics Investigation (GGI) team.

 

Over the last month, I've been examining numerous theoretical and modeling questions to attempt to explain the processes at work within Pluto's frozen plains, known as Sputnik Planum (SP). In a separate, yet parallel vein, I'm also studying the nature of glacial flows onto SP from the highlands bordering its eastern shoreline. In this blog, I will talk about the glacial flow problem.

 

First, let's look at some pictures of glacial flow on Pluto's frozen plains.

 

These are two views of the same part of the eastern side of SP-one is a nearly overhead snapshot, while the other one is a very low-incidence angle image, dramatically displaying the relief of the landscape. In the overhead image you can see dark streaks emanating from the right leading onto the open plane tracing a lobate pattern - kind of like hot wax moving down an inclined plane.

 

The dark materials are reminiscent of glacial moraines seen on Earth, but because this is Pluto, we have no idea what this dark material is, and whether or not the patterns we see are indeed moraines in the traditional terrestrial sense.

 

However, we do know what our colleagues on the New Horizons Composition team tell us: they have pretty solidly (ahem!) determined that the surface material on and in the near vicinity of SP is mainly made up of nitrogen, carbon monoxide, and methane ices, although their relative proportions are not yet determined.

 

In my initial considerations, I assume the flowing material is made of mostly nitrogen with some carbon monoxide, both of which have similar molecular bond structures. Based on what little lab work has been done on their properties under cold temperatures characteristic of Pluto's surface (-390 degrees Fahrenheit or 38 Kelvin), these volatiles ought to flow more slowly than silly putty, but much faster than glacial water ice on Earth.

 

The response timescales appropriate for these volatiles with the scale and relief of the highlands seen around Sputnik Planum leads us to the geophysical insight that these high relief structures (icy mountains) are probably not made up of any of these pure volatile ices, because they would have flattened out a long time ago. Instead, we speculate that the highlands are more likely made of a very strong structurally rigid water ice "bedrock" covered by a very thin coating of nitrogen and/or carbon monoxide ice.

 

This is where I come in: I fold all of this laboratory information about the volatile ices, as well as various geophysical insights into a numerical simulation platform I built a year ago that models glacial flow. This tool is used to examine various scientific hypotheses from me and other members of the geology team.

 

For example, one task is to examine possible scenarios explaining how the observed lobate pattern (think hot wax) comes about, and whether or not a nitrogen glacial model can explain what we see. To accomplish this, I start with a Digital Elevation Model (DEM) seen above, using stereo imaging of Pluto's surface with vertical relief on the order of .6 miles (1 kilometer). I use this model as my bedrock surface-then I add nitrogen ice and study the response.

 

To show you an example of the kind of response the model can exhibit, consider the figure above, where I take this surface bedrock and add glacial nitrogen ice, indicated by the red ellipse on the left figure. To this model I also add a feature representing the uniform accumulation of deposited nitrogen ice, in the amount of about one yard (one meter) per year. The outflow state is shown in the right panel.

 

In this artificial example, I have put in nearly 400 yards (400 meters) of ice inside the circled red region. The final flow state - including nice frontal lobes - gets there in about 20 Earth years. This is fast! You can also see accumulation of nitrogen ice inside of craters; this is because the steady deposition of ice also runs down steep-sided slopes and collects inside.

 

In understanding complex Pluto, progress is slow, but we are making progress. Stick around for the next installment of my blog, in about a month, when I will have more cool results!

http://www.spacedaily.com/reports/Probing_the_Mysterious_Glacial_Flow_on_Plutos_Frozen_Heart_999.html

 

Sputnik_Planum_2-1024x413.thumb.jpg.49ac

This low incidence angle indicates flow patterns from the lower right of the image, extending to the center of Pluto’s informally-named Sputnik Planum. Credits: NASA/JHUAPL/SwRI

 

Quote

These are two views of the same part of the eastern side of SP—one is a nearly overhead snapshot, while the other one is a very low-incidence angle image, dramatically displaying the relief of the landscape. In the overhead image you can see dark streaks emanating from the right leading onto the open plane tracing a lobate pattern – kind of like hot wax moving down an inclined plane. The dark materials are reminiscent of glacial moraines seen on Earth, but because this is Pluto, we have no idea what this dark material is, and whether or not the patterns we see are indeed moraines in the traditional terrestrial sense.

 

However, we do know what our colleagues on the New Horizons Composition team tell us: they have pretty solidly (ahem!) determined that the surface material on and in the near vicinity of SP is mainly made up of nitrogen, carbon monoxide, and methane ices, although their relative proportions are not yet determined.

https://blogs.nasa.gov/pluto/2016/01/08/probing-the-mysterious-glacial-flow-on-plutos-frozen-heart/

 

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New Surface Details Revealed On Ceres

 

ooPIA20193.thumb.jpg.4f8187073480b6e222b

Vertical image, Ceres    NASA

 

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Features on dwarf planet Ceres that piqued the interest of scientists throughout 2015 stand out in exquisite detail in the latest images from NASA's Dawn spacecraft, which recently reached its lowest-ever altitude at Ceres.

 

Dawn took these images near its current altitude of 240 miles (385 kilometers) from Ceres, between Dec. 19 and 23, 2015. More imagery

Kupalo Crater, one of the youngest craters on Ceres, shows off many fascinating attributes at the high image resolution of 120 feet (35 meters) per pixel. The crater has bright material exposed on its rim, which could be salts, and its flat floor likely formed from impact melt and debris. Researchers will be looking closely at whether this material is related to the "bright spots" of Occator Crater. Kupalo, which measures 16 miles (26 kilometers) across and is located at southern mid-latitudes, is named for the Slavic god of vegetation and harvest.

 

"This crater and its recently-formed deposits will be a prime target of study for the team as Dawn continues to explore Ceres in its final mapping phase," said Paul Schenk, a Dawn science team member at the Lunar and Planetary Institute, Houston.

 

Dawn's low vantage point also captured the dense network of fractures on the floor of 78-mile-wide (126-kilometer-wide) Dantu Crater. One of the youngest large craters on Earth's moon, called Tycho, has similar fractures. This cracking may have resulted from the cooling of impact melt, or when the crater floor was uplifted after the crater formed.

 

A 20-mile (32-kilometer) crater west of Dantu is covered in steep slopes, called scarps, and ridges. These features likely formed when the crater partly collapsed during the formation process. The curvilinear nature of the scarps resembles those on the floor of Rheasilvia, the giant impact crater on protoplanet Vesta, which Dawn orbited from 2011 to 2012.

 

Dawn's other instruments also began studying Ceres intensively in mid-December. The visible and infrared mapping spectrometer is examining how various wavelengths of light are reflected by Ceres, which will help identify minerals present on its surface.

 

Dawn's gamma ray and neutron detector (GRaND) is also keeping scientists busy. Data from GRaND help researchers understand the abundances of elements in Ceres' surface, along with details of the dwarf planet's composition that hold important clues about how it evolved. 

 

The spacecraft will remain at its current altitude for the rest of its mission, and indefinitely afterward. The end of the prime mission will be June 30, 2016.

 

"When we set sail for Ceres upon completing our Vesta exploration, we expected to be surprised by what we found on our next stop. Ceres did not disappoint," said Chris Russell, principal investigator for the Dawn mission, based at the University of California, Los Angeles. "Everywhere we look in these new low- altitude observations, we see amazing landforms that speak to the unique character of this most amazing world."


Dawn is the first mission to visit a dwarf planet, and the first mission outside the Earth-moon system to orbit two distinct solar system targets. After orbiting Vesta for 14 months in 2011 and 2012, it arrived at Ceres on March 6, 2015.

 

Dawn's mission is managed by the Jet Propulsion Laboratory for NASA's Science Mission Directorate in Washington. Dawn is a project of the directorate's Discovery Program, managed by NASA's Marshall Space Flight Center in Huntsville, Alabama. UCLA is responsible for overall Dawn mission science. Orbital ATK Inc., in Dulles, Virginia, designed and built the spacecraft. The German Aerospace Center, Max Planck Institute for Solar System Research, Italian Space Agency and Italian National Astrophysical Institute are international partners on the mission team. For a complete list of mission participants, visit: http://dawn.jpl.nasa.gov/mission

 

More information about Dawn is available at the following sites: http://dawn.jpl.nasa.gov and http://www.nasa.gov/dawn

http://spaceref.com/ceres/new-surface-details-revealed-on-ceres.html

 

More images at... (nice images)

http://www.jpl.nasa.gov/news/news.php?release=2016-008

 

:)

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Draggendrop    5,747

Juno Spacecraft Breaks Solar Power Distance Record

 

PIA13746_ip.thumb.jpg.a45c20e775127cc87f

Launching from Earth in 2011, the Juno spacecraft will arrive at Jupiter in 2016 to study the giant planet from an elliptical, polar orbit. Juno will repeatedly dive between the planet and its intense belts of charged particle radiation, coming only 5,000 kilometers (about 3,000 miles) from the cloud tops at closest approach. Image courtesy NASA/JPL-Caltech.

 

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NASA's Juno mission to Jupiter has broken the record to become humanity's most distant solar-powered emissary. The milestone occurred at 11 a.m. PST (2 p.m. EST, 19:00 UTC) on Wednesday, Jan. 13, when Juno was about 493 million miles (793 million kilometers) from the sun.

 

The previous record-holder was the European Space Agency's Rosetta spacecraft, whose orbit peaked out at the 492-million-mile (792-million-kilometer) mark in October 2012, during its approach to comet 67P/Churyumov-Gerasimenko.

 

"Juno is all about pushing the edge of technology to help us learn about our origins," said Scott Bolton, Juno principal investigator at the Southwest Research Institute in San Antonio. "We use every known technique to see through Jupiter's clouds and reveal the secrets Jupiter holds of our solar system's early history. It just seems right that the sun is helping us learn about the origin of Jupiter and the other planets that orbit it."

 

Launched in 2011, Juno is the first solar-powered spacecraft designed to operate at such a great distance from the sun. That's why the surface area of solar panels required to generate adequate power is quite large. The four-ton Juno spacecraft carries three 30-foot-long (9-meter) solar arrays festooned with 18,698 individual solar cells.

 

At Earth distance from the sun, the cells have the potential to generate approximately 14 kilowatts of electricity. But transport those same rectangles of silicon and gallium arsenide to a fifth rock from the sun distance, and it's a powerfully different story.

 

"Jupiter is five times farther from the sun than Earth, and the sunlight that reaches that far out packs 25 times less punch," said Rick Nybakken, Juno's project manager from NASA's Jet Propulsion Laboratory in Pasadena, Calif.

 

"While our massive solar arrays will be generating only 500 watts when we are at Jupiter, Juno is very efficiently designed, and it will be more than enough to get the job done."

Prior to Juno, eight spacecraft have navigated the cold, harsh underlit realities of deep space as far out as Jupiter.

 

All have used nuclear power sources to get their job done. Solar power is possible on Juno due to improved solar-cell performance, energy-efficient instruments and spacecraft, a mission design that can avoid Jupiter's shadow, and a polar orbit that minimizes the total radiation.

 

Juno's maximum distance from the sun during its 16-month science mission will be about 517 million miles (832 million kilometers), an almost five percent increase in the record for solar-powered space vehicles.

 

"It is cool we got the record and that our dedicated team of engineers and scientists can chalk up another first in space exploration," said Bolton. "But the best is yet to come. We are achieving these records and venturing so far out for a reason - to better understand the biggest world in our solar system and thereby better understand where we came from."

 

Juno will arrive at Jupiter on July 4 of this year. Over the next year the spacecraft will orbit the Jovian world 33 times, skimming to within 3,100 miles (5,000 kilometers) above the planet's cloud tops every 14 days. During the flybys, Juno will probe beneath the obscuring cloud cover of Jupiter and study Jupiter's aurorae to learn more about the planet's origins, structure, atmosphere and magnetosphere.

http://www.solardaily.com/reports/Juno_Spacecraft_Breaks_Solar_Power_Distance_Record_999.html

 

larger images and overview....

http://www.jpl.nasa.gov/spaceimages/details.php?id=pia13746

 

:)

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Draggendrop    5,747
Draggendrop    5,747

Cascading Magnetic Arches on The Sun

 

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A dark solar filament above the sun's surface became unstable and erupted on Dec. 16-17, 2015, generating a cascade of magnetic arches.

 

A small eruption to the upper right of the filament was likely related to its collapse. The arches of solar material appear to glow as they emit light in extreme ultraviolet wavelengths, highlighting the charged particles spinning along the sun's magnetic field lines. This video was taken in extreme ultraviolet wavelengths of 193 angstroms, a type of light that is typically invisible to our eyes, but is colorized here in bronze.

 

Credit: NASA/SDO

NASA’s SDO Captures Cascading Magnetic Arches, video is 0:16 min.

 

 

 

 

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Get Up Early, See Five Planets at Once!

 

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Over the next two weeks, for the first time in more than a decade, you can see all of the naked-eye planets — from Mercury to Saturn — together in the predawn sky.

 

If you follow celestial comings and goings at all, you know that bright planets have been largely missing from the evening sky for a few months. Sure, with careful watching you could have spotted Saturn low in the southwest as late as November, and Mercury put in a brief appearance a few weeks ago.

 

But really all the action has been in the sky before sunrise. Anchored by bright Venus and Jupiter, joined by Mars and Saturn, this planetary fab four has been dominating skywatchers' attention for months. (Did you catch last October's triple play involving Venus, Jupiter, and Mars?)

 

The show far from over. In fact, during the next two weeks you'll have a good chance to view five planets at once. It's a real visual treat, so don't pass up the chance to see it.

 

(You might see posts elsewhere that suggest this event runs from January 20th to February 20th. Technically, that's true — in his book More Mathematical Morsels, celestial dynamical Jean Meeus notes these dates. But realistically you're not going to see Mercury for a whole month. Instead, I suggest that the last week of January and first week of February are your "best bets" for success.)

 

Let's set the stage. You'll need to be outside about 45 minutes before sunrise. This time of year, if you work or go to school, you're usually already up by then — maybe even well positioned to scan the predawn eastern horizon as you commute to work or head off to school.

 

5_planets_25Jan2016_m-630x318.thumb.jpg.

Get up before dawn between January 22 and February 10th to glimpse all five naked-eye planets at once. This view is plotted as they'll appear 45 minutes before sunrise on January 25th. In the days thereafter, Mercury will climb higher (closer to Venus) and get brighter — making it easier to spot. At month's end, the waning Moon will join the celestial party.
Sky & Telescope diagram

 

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Venus is obvious as it lingers above the southeastern horizon. It's actually in decline, not nearly as high up as you saw it toward the end of 2015. But Venus has no equal for brightness among the night's planets and stars. Way over to the right, on the southwestern side of the sky, is Jupiter. In between are four bright beacons: not far from Venus are Saturn and, below it, the star Antares. Shift your gaze farther right to sweep up Mars, then the star Spica, and finally Jupiter.

 

The fifth planet is Mercury, which was spotable low in the southwest after sunset just two weeks ago. But it's been racing rapidly from evening to morning visibility. (The fleetest of planets can do that, since it circles the Sun in just 88 days.) Your first good chance to spot Mercury before dawn comes later this week. By Friday, the 22nd, find a clear view toward southeast and look 5° above the horizon. That's about the width of your three middle fingers held together at arm's length. It's along a diagonal from Saturn through Venus, about as far from Venus as Saturn is. Day by day, Mercury will appear a little higher up and a little brighter. By month's end, it'll be easy to spot.

 

A Plane of Planets

As you sweep your gaze from Mercury toward Jupiter, an arc of roughly 110°, notice that all these planets line along a single arc across the sky. That's no accident. All of the major planets lie very near the plane of Earth's orbit, which projects as a line — the ecliptic — across the sky. By defniition, the Sun always lies on the ecliptic — and our Moon is never far from it either. It's the superhighway of planetary motion among the stars.

 

As you're gazing at all these planets, think about their varied distances from us? Astronomers use the average Earth-Sun distance, called an astronomical unit, as a handy yardstick for intra-solar-system distances. Of the five planets you're seeing, right now Mercury is closest (about 0.8 a.u.), followed by Venus (1.3), Mars (1.4), Jupiter (4.7) and Saturn (10.6). The reflected sunlight you see coming from mercury took a brief 6½ minutes to reach Earth, where that from Saturn took just under 1½ hours to get here.

 

But don't let the vastness of interplanetary space keep you from enjoying for the simple visual beauty that awaits you before dawn. We haven't had this opportunity since this time 11 years ago. Back then their order in the sky briefly matched their relative order outward from the Sun. This time, Mars and Saturn apparently didn't get the memo, but we'll happily overlook that, right?

http://www.skyandtelescope.com/astronomy-news/observing-news/get-up-early-see-five-planets-at-once-01182015/

 

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Rover uses Rock Abrasion Tool to grind rocks

 

mars-merb-rock-abrasion-tool-rock-gagari

File image: Rock Abrasion Tool (RAT).

 

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Opportunity is inside 'Marathon Valley' on north-facing slopes for improved solar array energy production.

 

The rover is engaged in an in-situ (contact) science campaign investigating the surface target 'Pvt. John Potts' (informally named for members of the Lewis and Clark expedition).

 

Opportunity is performing successive grinds into the target to prepare a clean surface for elemental analysis by the Alpha Particle X-ray Spectrometer (APXS).

 

An initial grid by the Rock Abrasion Tool (RAT) had been previously completed, so a survey of the grind was performed on Sol 4248 (Jan. 5, 2016), with the Microscopic Imager (MI) with an initial analysis with the APXS.

 

Color Pancam panoramas of various targets were collected on Sols 4249 and 4250 (Jan. 6 and 7, 2016).

 

On Sol 4253 (Jan. 10, 2016), a seek scan with the RAT bit was performed in setup to another RAT grind on a subsequent sol. On Sol 4255 (Jan. 12, 2016), two steps of a deeper grind were performed on the target.

 

The RAT was left in place so even deeper grinding could be performed later.

 

As of Sol 4255 (Jan. 12, 2016), the solar array energy production was 452 watt-hours with an atmospheric opacity (Tau) of 0.446 and an improved solar array dust factor of 0.666.

 

Total odometry is 26.50 miles (42.65 kilometers), more than a marathon.

http://www.marsdaily.com/reports/Rover_uses_Rock_Abrasion_Tool_to_grind_rocks_999.html

 

Mission site

http://mars.nasa.gov/mer/home/

 

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Opportunity, also known as MER-B (Mars Exploration Rover – B) or MER-1, is a robotic rover active on Mars since 2004.[1]

 

Launched on July 7, 2003 as part of NASA's Mars Exploration Rover program, it landed in Meridiani Planum on January 25, 2004, three weeks after its twin Spirit (MER-A) touched down on the other side of the planet.[7]

 

With a planned 90 sol duration of activity, Spirit functioned until getting stuck in 2009 and ceased communications in 2010, while Opportunity remains active as of 2016, having already exceeded its operating plan by 11 years, 268 days (in Earth time).

 

Opportunity has continued to move, gather scientific observations, and report back to Earth for over 47 times its designed lifespan.

https://en.wikipedia.org/wiki/Opportunity_(rover)

 

:)

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Draggendrop    5,747

Rings of Saturn and 2 Moons Shine in Gorgeous NASA Photo

 

saturn-rings-janus-tethys.thumb.jpg.0ab1

Saturn's moons Tethys (left) and Janus hang near the planet's rings in this image captured on Oct. 27, 2015 by NASA's Cassini spacecraft.
Credit: NASA/JPL-Caltech/Space Science Institute

 

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Two very different Saturn moons hang near the giant planet's iconic rings in a beatiful new photo from NASA's Cassini spacecraft.

The photo, which was taken on Oct. 27 but just released Tuesday (Jan. 19), shows the spherical Tethys and the lumpy Janus, whose disparate shapes are a direct result of their divergent sizes.

 

"Moons like Tethys (660 miles or 1,062 kilometers across) are large enough that their own gravity is sufficient to overcome the material strength of the substances they are made of (mostly ice in the case of Tethys) and mold them into spherical shapes," NASA officials wrote in a description of the image.

 

"But small moons like Janus (111 miles or 179 kilometers across) are not massive enough for their gravity to form them into a sphere," they added. "Janus and its like are left as irregularly shaped bodies."

 

Cassini was about 593,000 miles (955,000 km) from Janus and 810,000 miles (1.3 million km) from Tethys when it took the picture, NASA officials said. The new photo depics Janus with a resolution of 3.7 miles (6 km) per pixel, and Tethys with a resolution of 5 miles (8 km) per pixel.

 

Tethys is the fifth-largest of Saturn's 62 moons. The biggest Saturn satellite, Titan, is nearly five times wider than Tethys, at 3,200 miles (5,150 km) in diameter. (Titan is about 50 percent wider than Earth's moon, and is the second-largest moon in the solar system, behind the Jovian satellite Ganymede.)

 

The $3.2 billion Cassini mission is a joint effort involving NASA, the European Space Agency and the Italian Space Agency. The Cassini spacecraft launched in 1997, arrived in the Saturn system in 2004, and delivered a lander called Huygens to Titan's surface in early 2005.

 

Cassini will continue studying Saturn and its moons until September 2017, when the probe will intentionally plunge into the ringed planet's atmosphere.

http://www.space.com/31663-saturn-rings-moons-tethys-janus-photo.html

 

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NASA's Van Allen Probes Revolutionize View of Radiation Belts

 

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About 600 miles from Earth's surface is the first of two donut-shaped electron swarms, known as the Van Allen Belts, or the radiation belts. Understanding the shape and size of the belts, which can shrink and swell in response to incoming radiation from the sun, is crucial for protecting our technology in space. The harsh radiation isn't good for satellites' health, so scientists wish to know just which orbits could be jeopardized in different situations.

 

Since the 1950s, when scientists first began forming a picture of these rings of energetic particles, our understanding of their shape has largely remained unchanged - a small, inner belt, a largely-empty space known as the slot region, and then the outer belt, which is dominated by electrons and which is the larger and more dynamic of the two. But a new study of data from NASA's Van Allen Probes reveals that the story may not be so simple.

nasa-earth-radiation-belt-discovery.thum

Two giant swaths of radiation, known as the Van Allen Belts, surrounding Earth were discovered in 1958. In 2012, observations from the Van Allen Probes showed that a third belt can sometimes appear. The radiation is shown here in yellow, with green representing the spaces between the belts.
Credit: NASA/Van Allen Probes/Goddard Space Flight Center

 

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"The shape of the belts is actually quite different depending on what type of electron you're looking at," said Geoff Reeves from Los Alamos National Laboratory and the New Mexico Consortium in Los Alamos, New Mexico, lead author on the study published on Dec. 28, 2015, in the Journal of Geophysical Research. "Electrons at different energy levels are distributed differently in these regions."

 

Rather than the classic picture of the radiation belts - small inner belt, empty slot region and larger outer belt - this new analysis reveals that the shape can vary from a single, continuous belt with no slot region, to a larger inner belt with a smaller outer belt, to no inner belt at all. Many of the differences are accounted for by considering electrons at different energy levels separately.

 

"It's like listening to different parts of a song," said Reeves. "The bass line sounds different from the vocals, and the vocals are different from the drums, and so on."

 

The researchers found that the inner belt - the smaller belt in the classic picture of the belts - is much larger than the outer belt when observing electrons with low energies, while the outer belt is larger when observing electrons at higher energies. At the very highest energies, the inner belt structure is missing completely. So, depending on what one focuses on, the radiation belts can appear to have very different structures simultaneously.

 

These structures are further altered by geomagnetic storms. When fast-moving magnetic material from the sun - in the form of high-speed solar wind streams or coronal mass ejections - collide with Earth's magnetic field, they send it oscillating, creating a geomagnetic storm. Geomagnetic storms can increase or decrease the number of energetic electrons in the radiation belts temporarily, though the belts return to their normal configuration after a time.

 

These storm-driven electron increases and decreases are currently unpredictable, without a clear pattern showing what type or strength of storm will yield what outcomes. There's a saying in the space physics community: if you've seen one geomagnetic storm, you've seen one geomagnetic storm. As it turns out, those observations have largely been based on electrons at only a few energy levels.

 

"When we look across a broad range of energies, we start to see some consistencies in storm dynamics," said Reeves. "The electron response at different energy levels differs in the details, but there is some common behavior. For example, we found that electrons fade from the slot regions quickly after a geomagnetic storm, but the location of the slot region depends on the energy of the electrons."

 

Often, the outer electron belt expands inwards toward the inner belt during geomagnetic storms, completely filling in the slot region with lower-energy electrons and forming one huge radiation belt. At lower energies, the slot forms further from Earth, producing an inner belt that is bigger than the outer belt. At higher energies, the slot forms closer to Earth, reversing the comparative sizes.

 

The twin Van Allen Probes satellites expand the range of energetic electron data we can capture. In addition to studying the extremely high-energy electrons - carrying millions of electron volts - that had been studied before, the Van Allen Probes can capture information on lower-energy electrons that contain only a few thousand electron volts. Additionally, the spacecraft measure radiation belt electrons at a greater number of distinct energies than was previously possible.

 

"Previous instruments would only measure five or ten energy levels at a time," said Reeves. "But the Van Allen Probes measure hundreds."

Measuring the flux of electrons at these lower energies has proved difficult in the past because of the presence of protons in the radiation belt regions closest to Earth. These protons shoot through particle detectors, creating a noisy background from which the true electron measurements needed to be picked out. But the higher-resolution Van Allen Probes data found that these lower-energy electrons circulate much closer to Earth than previously thought.

 

"Despite the proton noise, the Van Allen Probes can unambiguously identify the energies of the electrons it's measuring," said Reeves.

Precise observations like this, from hundreds of energy levels, rather than just a few, will allow scientists to create a more precise and rigorous model of what, exactly, is going on in the radiation belts, both during geomagnetic storms and during periods of relative calm.

 

"You can always tweak a few parameters of your theory to get it to match observations at two or three energy levels," said Reeves. "But having observations at hundreds of energies constrain the theories you can match to observations."

http://www.spacedaily.com/reports/NASAs_Van_Allen_Probes_Revolutionize_View_of_Radiation_Belts_999.html

 

From 2 years ago...gives a background...

NASA Discovers New Radiation Belt Around Earth

http://www.space.com/20004-earth-radiation-belt-discovery.html

 

and generic description...

Van Allen radiation belt

http://www.britannica.com/science/Van-Allen-radiation-belt

 

6031-004-89E5D4FB.thumb.jpg.39da6a2536e8

 

:D

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Draggendrop    5,747

Curiosity gets a good taste of scooped, sieved sand

 

mars-curiosity-rover-sand-dune-bagnold-f

This view captures Curiosity's current work area where the rover continues its campaign to study an active sand dune on Mars. Image courtesy NASA/JPL-Caltech.

 

Quote

At its current location for inspecting an active sand dune, NASA's Curiosity Mars rover is adding some sample-processing moves not previously used on Mars. Sand from the second and third samples the rover is scooping from "Namib Dune" will be sorted by grain size with two sieves. The coarser sieve is making its debut, and using it also changes the way the treated sample is dropped into an inlet port for laboratory analysis inside the rover.

Positioning of the rover to grab a bite of the dune posed a challenge, too. Curiosity reached this sampling site, called "Gobabeb," on Jan. 12.

 

"It was pretty challenging to drive into the sloping sand and then turn on the sand into the position that was the best to study the dunes," said Michael McHenry of NASA's Jet Propulsion Laboratory, Pasadena, California. He is the Curiosity mission's campaign rover planner for collecting these samples.

 

Curiosity has scooped up sample material at only one other site since it landed on Mars in August 2012. It sampled dust and sand at a windblown drift site called "Rocknest" in October and November 2012. Between there and Gobabeb, the rover collected sample material for analysis at nine rock targets, by drilling rather than scooping.

 

The mission's current work is the first close-up study of active sand dunes anywhere other than Earth. Namib and nearby mounds of dark sand are part of the "Bagnold Dune Field," which lines the northwestern flank of a layered mountain where Curiosity is examining rock records of ancient environmental conditions on Mars. Investigation of the dunes is providing information about how wind moves and sorts sand particles in conditions with much less atmosphere and less gravity than on Earth.

 

Sand in dunes has a range of grain sizes and compositions. Sorting by wind will concentrate certain grain sizes and compositions, because composition is related to density, based on where and when the wind has been active.

 

The Gobabeb site was chosen to include recently formed ripples. Information about these aspects of Mars' modern environment may also aid the mission's interpretation of composition variations and ripple patterns in ancient sandstones that formed from wind or flowing water.

 

Curiosity scooped its first dune sample on Jan. 14, but the rover probed the dune first by scuffing it with a wheel. "The scuff helped give us confidence we have enough sand where we're scooping that the path of the scoop won't hit the ground under the sand," McHenry said.

 

That first scoop was processed much as Rocknest samples were: A set of complex moves of a multi-chambered device on the rover's arm passed the material through a sieve that screened out particles bigger than 150 microns (0.006 inch); some of the material that passed the sieve was dropped into laboratory inlet ports from a "portioner" on the device; material blocked by the sieve was dumped onto the ground.

 

The portioner is positioned directly over an opened inlet port on the deck of the rover to drop a portion into it when the processing device is vibrating and a release door is opened. Besides analyzing samples delivered to its internal laboratory instruments, Curiosity can use other instruments to examine sample material dumped onto the ground.

 

Curiosity collected its second scoop of Gobabeb on Jan. 19. This is when the coarser sieve came into play. It allows particles up to 1 millimeter (1,000 microns or 0.04 inch) to pass through.

 

Sand from the second scoop was initially fed to the 150-micron sieve. Material that did not pass through that sieve was then fed to the 1-millimeter sieve. The fraction routed for laboratory analysis is sand grains that did not pass through the finer sieve, but did pass through the coarser one.

"What you have left is predominantly grains that are smaller than 1 millimeter and larger than 150 microns," said JPL's John Michael Morookian, rover planning team lead for Curiosity.

 

This fraction is dropped into a laboratory inlet by the scoop, rather than the portioner. Morookian decribed this step: "We start the vibration and gradually tilt the scoop. The material flows off the end of the scoop, in more of a stream than all at once."

 

Curiosity reached the base of Mount Sharp in 2014 after fruitfully investigating outcrops closer to its landing site and then trekking to the layered mountain. On the lower portion of the mountain, the mission is studying how Mars' ancient environment changed from wet conditions favorable for microbial life to harsher, drier conditions.

http://www.marsdaily.com/reports/Curiosity_gets_a_good_taste_of_scooped_sieved_sand_999.html

 

:)

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Draggendrop    5,747

At Saturn, Cassini Spacecraft Adjusts Orbit for Titan-ic 'Grand Finale'

 

cassini-spacecraft-saturn-illustration.t

Artist's illustration of NASA's Cassini spacecraft at Saturn.

Credit: NASA/JPL-Caltech

 

Quote

NASA's Cassini probe has begun reshaping its orbit around Saturn in preparation for the spacecraft's "grand finale" at the ringed planet next year.

 

Cassini performed a 35-second engine burn on Saturday (Jan. 23) to set up an orbit-changing Feb. 1 flyby of Saturn's huge moon Titan. It was the second of five such burns Cassini will conduct, all of which will be followed by a close encounter with Titan.

 

"Titan does all the heavy lifting," Cassini project manager Earl Maize, of NASA's Jet Propulsion Laboratory (JPL) in Pasadena, California, said in a statement. "Our job is to get the spacecraft to a precise altitude and latitude above Titan, at a particular time, and these large propulsive maneuvers are what keep us on target to do that." 

 

The Jan. 23 burn changed Cassini's velocity by 22.3 feet (6.8 meters) per second, whereas the Feb. 1 Titan flyby will adjust the probe's speed by 2,539 feet (774 m) per second, NASA officials said.

 

The first engine firing occurred on Dec. 30, which set up a Jan. 15 Titan flyby. The next burn is planned for March 25, with the subsequent Titan encounter occurring on April 4, NASA officials said.

 

The overall goal of these maneuvers is to get Cassini to a higher plane above Saturn's equator, which the probe has been circling since 2015.

"By late November, the spacecraft will be on a path that will carry it high above Saturn's poles, approaching just outside the planet's main rings — a period the mission team calls the 'F-ring orbits,'" NASA officials wrote in the same statement. "After 20 F-ring orbits, Cassini will begin its Grand Finale event, in which the spacecraft will pass 22 times between the innermost rings and the planet before plunging into Saturn's atmosphere to end its journey on Sept. 15, 2017."

 

The $3.2 billion Cassini mission, a joint effort involving NASA, the European Space Agency and the Italian Space Agency, launched in 1997 and arrived in the Saturn system in 2004. In addition to its own science work, Cassini delivered a piggyback probe called Huygens onto Titan's surface in January 2005. 

 

Cassini has returned countless spectacular images of Saturn and its moons, and it has made a number of important discoveries. For example, in 2005, the spacecraft spotted geysers of water ice blasting from the south pole of the Saturn moon Enceladus. Cassini has flown through the plume generated by these geysers and found carbon-containing organic molecules — the building blocks of life as we know it — within it.

 

The mission's home stretch should be productive as well, Cassini team members said.

 

"We have an exciting year of Saturn science planned as we head for higher ground. And the views along the way should be spectacular," Cassini project scientist Linda Spilker, also of JPL, said in the same statement.

http://www.space.com/31740-saturn-cassini-spacecraft-titan-maneuvers.html

 

:)

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Draggendrop    5,747

Over the years, the mechanism for which the Earth and Moon, came about, has been battled for...here is the latest insight...

 

The Moon Was Produced by a Head-on Collision

 

ooTheia.thumb.jpg.867bcfd67256251c19f6a1

Moon Formation          WILLIAM K. HARTMANN

 

Quote

The Moon was formed by a violent, head-on collision between the early Earth and a "planetary embryo" called Theia approximately 100 million years after the Earth formed, UCLA geochemists and colleagues report.

 

Scientists had already known about this high-speed crash, which occurred almost 4.5 billion years ago, but many thought the Earth collided with Theia (pronounced THAY-eh) at an angle of 45 degrees or more -- a powerful side-swipe. New evidence reported Jan. 29 in the journal Science substantially strengthens the case for a head-on assault.

 

The researchers analyzed seven rocks brought to the Earth from the Moon by the Apollo 12, 15 and 17 missions, as well as six volcanic rocks from the Earth's mantle -- five from Hawaii and one from Arizona.

 

The key to reconstructing the giant impact was a chemical signature revealed in the rocks' oxygen atoms. (Oxygen makes up 90 percent of rocks' volume and 50 percent of their weight.) More than 99.9 percent of Earth's oxygen is O-16, so called because each atom contains eight protons and eight neutrons. But there also are small quantities of heavier oxygen isotopes: O-17, which have one extra neutron, and O-18, which have two extra neutrons. Earth, Mars and other planetary bodies in our solar system each has a unique ratio of O-17 to O-16 -- each one a distinctive "fingerprint."

In 2014, a team of German scientists reported in Science that the Moon also has its own unique ratio of oxygen isotopes, different from Earth's. The new research finds that is not the case.

 

"We don't see any difference between the Earth's and the Moon's oxygen isotopes; they're indistinguishable," said Edward Young, lead author of the new study and a UCLA professor of geochemistry and cosmochemistry.

 

Young's research team used state-of-the-art technology and techniques to make extraordinarily precise and careful measurements, and verified them with UCLA's new mass spectrometer.

 

The fact that oxygen in rocks on the Earth and our Moon share chemical signatures was very telling, Young said. Had Earth and Theia collided in a glancing side blow, the vast majority of the Moon would have been made mainly of Theia, and the Earth and Moon should have different oxygen isotopes. A head-on collision, however, likely would have resulted in similar chemical composition of both Earth and the Moon.

 

"Theia was thoroughly mixed into both the Earth and the Moon, and evenly dispersed between them," Young said. "This explains why we don't see a different signature of Theia in the Moon versus the Earth."

 

Theia, which did not survive the collision (except that it now makes up large parts of Earth and the Moon) was growing and probably would have become a planet if the crash had not occurred, Young said. Young and some other scientists believe the planet was approximately the same size as the Earth; others believe it was smaller, perhaps more similar in size to Mars.

 

Another interesting question is whether the collision with Theia removed any water that the early Earth may have contained. After the collision -- perhaps tens of millions of year later -- small asteroids likely hit the Earth, including ones that may have been rich in water, Young said. Collisions of growing bodies occurred very frequently back then, he said, although Mars avoided large collisions.

 

A head-on collision was initially proposed in 2012 by Matija Cuk, now a research scientist with the SETI Institute, and Sarah Stewart, now a professor at UC Davis; and, separately during the same year by Robin Canup of the Southwest Research Institute.

references/papers at the link

http://spaceref.com/moon/the-moon-was-produced-by-a-head-on-collision.html

 

:)

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Draggendrop    5,747

New Animation Takes a Colorful Flight Over Ceres

 

Quote

A colorful new animation shows a simulated flight over the surface of dwarf planet Ceres, based on images from NASA's Dawn spacecraft.

 

The movie shows Ceres in enhanced color, which helps to highlight subtle differences in the appearance of surface materials. Scientists believe areas with shades of blue contain younger, fresher material, including flows, pits and cracks.

 

The animated flight over Ceres emphasizes the most prominent craters, such as Occator, and the tall, conical mountain Ahuna Mons. Features on Ceres are named for earthly agricultural spirits, deities and festivals.

 

The movie was produced by members of Dawn's framing camera team at the German Aerospace Center, DLR, using images from Dawn's high-altitude mapping orbit. During that phase of the mission, which lasted from August to October 2015, the spacecraft circled Ceres at an altitude of about 900 miles (1,450 kilometers).

 

"The simulated overflight shows the wide range of crater shapes that we have encountered on Ceres. The viewer can observe the sheer walls of the crater Occator, and also Dantu and Yalode, where the craters are a lot flatter," said Ralf Jaumann, a Dawn mission scientist at DLR.

 

Dawn is the first mission to visit Ceres, the largest object in the main asteroid belt between Mars and Jupiter. After orbiting asteroid Vesta for 14 months in 2011 and 2012, Dawn arrived at Ceres in March 2015. The spacecraft is currently in its final and lowest mapping orbit, at about 240 miles (385 kilometers) from the surface.

 

Dawn's mission is managed by the Jet Propulsion Laboratory for NASA's Science Mission Directorate in Washington. Dawn is a project of the directorate's Discovery Program, managed by NASA's Marshall Space Flight Center in Huntsville, Alabama. UCLA is responsible for overall Dawn mission science. Orbital ATK Inc., in Dulles, Virginia, designed and built the spacecraft. The German Aerospace Center, Max Planck Institute for Solar System Research, Italian Space Agency and Italian National Astrophysical Institute are international partners on the mission team.

 

For a complete list of mission participants, visit: http://dawn.jpl.nasa.gov/mission

 

More information about Dawn is available at the following sites: http://dawn.jpl.nasa.gov
http://www.nasa.gov/dawn

http://spaceref.com/ceres/new-animation-takes-a-colorful-flight-over-ceres.html

 

Flight Over Dwarf Planet Ceres

video is 3:43 min.

 

 

 

:woot:

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Draggendrop    5,747

I was doing my usual gawking for science goodies, when I came across a reddit about a photo from 2014, from China's Yutu Rover, available online..This is one I don't remember and just had to post

 

this was the reddit...but the Chang'e 3 mission photo's from Mare Ibrium are online sourced.

https://www.reddit.com/r/space/comments/4393y0/the_moons_surface_in_true_color_and_high/

 

here is the photo...note: surface illumination was bright and decreases sensitivity, which is why no stars are visible..

 

9dfK0pK.jpg

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Draggendrop    5,747

NASA's New Planetary Defense Office Gets to Work Protecting Earth

 

neo-earth-illustration.thumb.jpg.286a0db

NASA's newly created Planetary Defense Coordination Office aims to deal with Earth-menacing space rocks.
Credit: ESA/P.Carril

 

 

Quote

A new NASA organization dedicated to protecting Earth from dangerous asteroids has hit the ground running.

 

In early January, NASA announced the establishment of a Planetary Defense Coordination Office (PDCO), which will synchronize U.S. efforts to deal with threatening near-Earth objects (NEOs) and will supervise all NASA-funded projects to find and characterize asteroids and comets that visit Earth's neighborhood.

 

"There is no identified threat that we know of right now," said Lindley Johnson, NASA's new planetary defense officer. 

 

"Our job is to look for that and identify a NEO as far in advance as we can," Johnson told Space.com in an exclusive interview. "Doing so means we have the maximum amount of time to appropriately deal with the object, be it a small impactor or something that's larger, calling for a kinetic impactor mission, or whatever needs to be done."

Large article..good read, with images...

http://www.space.com/31770-nasa-planetary-defense-office-asteroid-threat.html

 

Near Earth Objects list

http://neo.jpl.nasa.gov/ca/

 

:D

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Jim K    13,233
18 minutes ago, Draggendrop said:

NASA's New Planetary Defense Office Gets to Work Protecting Earth

About time.  Aside from humans (and maybe Yellowstone)...Asteroids are our biggest threat for survival.  Hopefully this is an everlasting venture that stays appropriately funded.  May not get hit by a "dinosaur killer" in the next hundreds or thousands of years ... then again we could get hit sometime sooner than that.

 

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Unobscured Vision    2,666

Ohhh yeah. The science returns the past year have been amazing. Drool-worthy. :yes: 

 

Now we need:

 

- JWST up there to find P-Nine, if it actually exists. That's the only instrument that'll be capable of resolving a disc -- depending on where it is in that theoretical orbit.

- Dedicated Uranus and Neptune missions like Cassini.

- Full-sky survey missions like Kepler and WISE, but better.

- Apply new technologies and advances in optics to upgrade existing observatories around the world

- OldSpace to get out of the way or adapt. (seriously)

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Draggendrop    5,747

Science returns are stunning. And to think that when I was in school, I was excited by a "black and white" artists impression of Pluto. Exciting times for all, particularly the young ones in school, who have a lot of resources for their studies now.

 

:)

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Unobscured Vision    2,666

Yep. And to think, we thought (and rightly so) that the Voyager I and II shots of Saturn and its' moons were "GQ Shots of the Century" ...

 

Then we got the Uranus System shots from Voyager II. Man, oh man. What a mind-blower.

 

And then Neptune and Triton .. nobody ever thought Neptune and Triton would be as they were. That was our first real look at an Ice Dwarf. :yes: Those cryo-plumes on Triton ... holy crap! I still remember the reactions of the scientists when they saw those. Goose bumps ... :D 

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Draggendrop    5,747

Dashcam captures fireball over DC

 

56af9e2ac461883f1d8b45d0.jpg

 

Quote

A bright meteor briefly lit up the skies over the US capital, before breaking up into fragments and fading away. Described as “huge” and “very bright,” the streak of fire could be seen as far away as Canada.
Dozens of people reported seeing the fiery streak in the sky, most likely a small meteor breaking up in Earth’s atmosphere, shortly after 6pm local time on Saturday.  Alexander Salvador captured it on his dashboard camera in the Washington, DC suburb of Falls Church, Virginia.

The fireball was visible from as far as Canada, but most reports came from the northeastern US. The Washington Post received tweets from Baltimore, New Jersey, New York, Michigan and Ontario.

https://www.rt.com/usa/330915-fireball-meteor-washington-virginia/

 

Fireball sighting in Falls Church, VA

video is 8 seconds...

 

 

 

//editor out to lunch just now....

:)

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Draggendrop    5,747

Understanding The Magnetic Sun

 

Quote

The surface of the sun writhes and dances.

Far from the still, whitish-yellow disk it appears to be from the ground, the sun sports twisting, towering loops and swirling cyclones that reach into the solar upper atmosphere, the million-degree corona - but these cannot be seen in visible light. Then, in the 1950s, we got our first glimpse of this balletic solar material, which emits light only in wavelengths invisible to our eyes.

 

Once this dynamic system was spotted, the next step was to understand what caused it. For this, scientists have turned to a combination of real time observations and computer simulations to best analyze how material courses through the corona. We know that the answers lie in the fact that the sun is a giant magnetic star, made of material that moves in concert with the laws of electromagnetism.

 

"We're not sure exactly where in the sun the magnetic field is created," said Dean Pesnell, a space scientist at NASA's Goddard Space Flight Center in Greenbelt, Maryland. "It could be close to the solar surface or deep inside the sun - or over a wide range of depths."

 

Getting a handle on what drives that magnetic system is crucial for understanding the nature of space throughout the solar system: The sun's magnetic field is responsible for everything from the solar explosions that cause space weather on Earth - such as auroras - to the interplanetary magnetic field and radiation through which our spacecraft journeying around the solar system must travel.

 

So how do we even see these invisible fields? First, we observe the material on the sun. The sun is made of plasma, a gas-like state of matter in which electrons and ions have separated, creating a super-hot mix of charged particles. When charged particles move, they naturally create magnetic fields, which in turn have an additional effect on how the particles move. The plasma in the sun, therefore, sets up a complicated system of cause and effect in which plasma flows inside the sun - churned up by the enormous heat produced by nuclear fusion at the center of the sun - create the sun's magnetic fields. This system is known as the solar dynamo.

 

We can observe the shape of the magnetic fields above the sun's surface because they guide the motion of that plasma - the loops and towers of material in the corona glow brightly in EUV images. Additionally, the footpoints on the sun's surface, or photosphere, of these magnetic loops can be more precisely measured using an instrument called a magnetograph, which measures the strength and direction of magnetic fields.

 

Next, scientists turn to models. They combine their observations - measurements of the magnetic field strength and direction on the solar surface - with an understanding of how solar material moves and magnetism to fill in the gaps. Simulations such as the Potential Field Source Surface, or PFSS, model - shown in the accompanying video - can help illustrate exactly how magnetic fields undulate around the sun. Models like PFSS can give us a good idea of what the solar magnetic field looks like in the sun's corona and even on the sun's far side.

 

A complete understanding of the sun's magnetic field - including knowing exactly how it's generated and its structure deep inside the sun - is not yet mapped out, but scientists do know quite a bit. For one thing, the solar magnetic system is known to drive the approximately-11-year activity cycle on the sun. With every eruption, the sun's magnetic field smooths out slightly until it reaches its simplest state. At that point the sun experiences what's known as solar minimum, when solar explosions are least frequent. From that point, the sun's magnetic field grows more complicated over time until it peaks at solar maximum, some 11 years after the previous solar maximum.

 

"At solar maximum, the magnetic field has a very complicated shape with lots of small structures throughout - these are the active regions we see," said Pesnell. "At solar minimum, the field is weaker and concentrated at the poles. It's a very smooth structure that doesn't form sunspots."

more at the link...

http://spaceref.com/solar-physics/understanding-the-magnetic-sun.html

 

and

 

http://www.eurekalert.org/pub_releases/2016-01/nsfc-nut012916.php

 

Understanding the Magnetic Sun

video is 1:56 min.

 

 

 

:)

 

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Draggendrop    5,747

A few post's back, there was a great "Moon image" from a collection that China has made available.

 

Fun with a new data set: Chang'e 3 lander and Yutu rover camera data

 

Quote

In a recent guest blog post, Quanzhi Ye pointed to the Chinese version of the Planetary Data System, and shared the great news that Chang'e 3 lander data are now public. The website is a little bit difficult to use, but last week I managed to download all of the data from two of the cameras -- a total of 35 Gigabytes of data! -- and I've spent the subsequent week figuring out what's there and how to handle it.

 

So, space fans, without further ado, here, for the first time in a format easily accessible to the public, are hundreds and hundreds of science-quality images from the Chang'e 3 lander and Yutu rover. I don't usually host entire data sets (PDS-formatted and all) but I made an exception in this case because the Chinese website is a bit challenging to use.

http://www.planetary.org/blogs/emily-lakdawalla/2016/01281656-fun-with-a-new-data-set-change.html?referrer=http://www.csmonitor.com/Science/2016/0201/China-shares-vivid-photos-of-the-moon-s-surface-with-the-world.-Why-now

 

Rover...

http://planetary.s3.amazonaws.com/data/change3/pcam.html

 

Lander...

http://planetary.s3.amazonaws.com/data/change3/tcam.html

 

here is a sample from each...

 

PCAML-C-026_SCI_N_20140112133751_0007_A_

 

TCAM-I-118_SCI_P_20131217162414_0004_A_2

 

Have fun...lots of pictures and formats....

 

:)

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Draggendrop    5,747

Today is methane day for Saturn.....

 

Viewing Methane On Saturn

 

pia18354-1041.jpg

Saturn    NASA

 

Quote

The soft, bright-and-dark bands displayed by Saturn in this view from NASA's Cassini spacecraft are the signature of methane in the planet's atmosphere.

 

This image was taken in wavelengths of light that are absorbed by methane on Saturn. Dark areas are regions where light travels deeper into the atmosphere (passing through more methane) before reflecting and scattering off of clouds and then heading back out of the atmosphere. In such images, the deeper the light goes, the more of it gets absorbed by methane, and the darker that part of Saturn appears.

 

The moon Dione (698 miles or 1,123 kilometers across) hangs below the rings at right. Shadows of the rings are also visible here, cast onto the planet's southern hemisphere, in an inverse view compared to early in Cassini's mission at Saturn.

 

This view looks toward the unilluminated side of the rings from about 0.3 degrees below the ringplane. The image was taken with the Cassini spacecraft wide-angle camera on Sept. 6, 2015, using a spectral filter which preferentially admits wavelengths of near-infrared light centered at 728 nanometers.

 

The view was acquired at a distance of approximately 819,000 miles (1.32 million kilometers) from Saturn. Image scale is 49 miles (79 kilometers) per pixel. Dione has been brightened by a factor of two to enhance its visibility.

http://spaceref.com/saturn/viewing-methane-on-saturn.html

 

 

Saturn Looks Regal in Cassini Photo, Methane Gas and All

 

saturn-the-mighty.thumb.jpg.89a6acc89648

An image of Saturn, taken by the Cassini probe on Sept. 15, 2015. The wavelength of light captured in this image is sensitive to the presence of methane. The moon Dione can be seen in the lower left of the image.
Credit: saturn, cassini, dione, saturn system, gas giant, Saturn methane, saturn rings

 

Quote

A new black-and-white photograph taken by the Cassini probe shows the methane gas on Saturn, and captures the planet's regal air.

 

The sixth planet from the sun is often defined by its system of rings, but the body of Saturn is also an incredible sight to behold. Though not as flamboyant as Jupiter, which seems to have countless number of colorful stripes and brilliant spots, Saturn still has a regal quality to it.

 

In this image, Cassini captured wavelengths of light that are absorbed by methane — darker regions indicate more methane. Looking down on the tiny moon Dione, Saturn is imposing and powerful, giving the impression of royalty, while its ring system serves as a finely crafted crown.

 

The Cassini mission is nearing the end of its incredible exploration of Saturn. In 2017, the probe will execute a series of death-defying dives through the planet's ring system, before crashing into the surface of the planet. This view was taken at a distance of about 819,000 miles (1.32 million kilometers) from Saturn.

 

In the new image, taken Sept. 6, 2015, the darker regions of the planet are places where the light travels deeper into Saturn's gaseous atmosphere. The deeper the light travels, the more of it is absorbed by methane, before bouncing off clouds and reflecting back out, away from the planet. 

Saturn's moon Dione is only 689 miles (1,123 km) across. It is one of 53 known moons orbiting Saturn. In the image, the light from Dione has been brightened to make it more visible.

 

The Cassini mission, a joint venture by NASA, the European Space Agency and the Italian Space Agency, began as the Cassini-Huygens mission. After dropping the Huygens probe onto the surface of Saturn's largest moon, Titan, in 2005, the Cassini probe continued to explore the Saturn system.

 

The Cassini-Huygens mission has led to many discoveries about the wild and wonderful Saturn system, including evidence of liquid water on the moon Enceladus, 50-mile landslides on the moon Iapetus, and a giant methane lake on Titan. The mission also discovered a new ring 8 million miles (12.9 million km) away from Saturn.

http://www.space.com/31804-saturn-cassini-photo-shows-methane.html

 

:D

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LOC    1,002

I'm always amazed at the beauty of Saturn whenever the rings shadow falls on the planet itself. So beautiful. Also, go Cassini!

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Draggendrop    5,747

Whenever I see those rings I want to suit up and float along with them....1:07 min mark of this 3:50 min video...

 

 

 

:D

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LOC    1,002

Carl Sagan, sigh. If he would have lived a bit longer, I could literally imagine his head exploding with all the things we've discovered over the last 15 years or so. He was such an important part of not only science education, but science in general. Plus, we got Contact out of him. One of my favorite movies ever. (and yes, I've read the novel as well :))

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