samedi 18 mars 2017

United Launch Alliance Successfully Launches of WGS-9 Mission


















ULA - Delta IV / WGS-9 Mission poster.


March 18, 2017

United Launch Alliance Commemorates U.S. Air Force 70th Anniversary with Successful Launch of WGS-9 Mission

Delta IV carrying WGS-9 launch

A United Launch Alliance (ULA) Delta IV rocket carrying the ninth Wideband Global SATCOM (WGS-9) satellite for the United States Air Force lifted off from Space Launch Complex-37 on March 18 at 8:18 p.m. EDT.

“This launch commemorates the 70th anniversary of the USAF.” said Laura Maginnis, ULA vice president of Government Satellite Launch. “We are absolutely honored to play a role in this important milestone, while safely delivering WGS-9 to orbit.”

Launch of Delta IV Rocket Carrying WGS-9 US Air Force Satellite

This mission was launched aboard a Delta IV Medium+ (5, 4) configuration Evolved Expendable Launch Vehicle (EELV) powered by one common booster core and four solid rocket motors built by Orbital ATK. The common booster core was powered by an RS-68A liquid hydrogen/liquid oxygen engine producing 705,250 pounds of thrust at sea level. A single RL10B-2 liquid hydrogen/liquid oxygen engine powered the second stage. The booster and upper stage engines are both built by Aerojet Rocketdyne. ULA constructed the Delta IV Medium+ (5,4) launch vehicle in Decatur, Alabama.

This is ULA’s 3rd launch in 2017 and the 118th successful launch since the company was formed in December 2006.

“Thank you to the women and men of United Launch Alliance and all of our teammates who have worked tirelessly together to ensure today's mission success,” said Maginnis. “The team’s number one priority was safely and reliably delivering one of our nation’s most critical satellites.”

WGS-9 satellite

WGS-9, the third Block II Follow-on satellite, supports communications links in the X-band and Ka-band spectra. The WGS-9 satellite will be able filter and downlink up to 8.088 GHz of bandwidth. WGS satellites are an important element of a new high-capacity satellite communications system providing enhanced communications capability to our troops in the field.

The EELV program was established by the U.S. Air Force to provide assured access to space for Department of Defense and other government payloads. The commercially developed EELV program supports the full range of government mission requirements, while delivering on schedule and providing significant cost savings over the heritage launch systems.

With more than a century of combined heritage, United Launch Alliance is the nation’s most experienced and reliable launch service provider. ULA has successfully delivered more than 115 satellites to orbit that provide critical capabilities for troops in the field, aid meteorologists in tracking severe weather, enable personal device-based GPS navigation and unlock the mysteries of our solar system.

For more information on ULA, visit the ULA website at http://www.ulalaunch.com. Join the conversation at http://www.facebook.com/ulalaunch, http://twitter.com/ulalaunch and http://instagram.com/ulalaunch.

Images, Video, Text, Credits: United Launch Alliance (ULA).

Greetings, Orbiter.ch

NASA Satellites Ready When Stars and Planets Align












NASA -  Goddard Space Flight Center logo.

March 18, 2017

The movements of the stars and the planets have almost no impact on life on Earth, but a few times per year, the alignment of celestial bodies has a visible effect. One of these geometric events — the spring equinox — is just around the corner, and another major alignment — a total solar eclipse — will be visible across America on Aug. 21, with a fleet of NASA satellites viewing it from space and providing images of the event.

To understand the basics of celestial alignments, here is information on equinoxes, solstices, full moons, eclipses and transits:

Equinox

Earth spins on a tilted axis. As our planet orbits around the sun, that tilt means that during half of the year, the Northern Hemisphere receives more daylight — its summertime — and during the other half of the year, the Southern Hemisphere does. Twice a year, Earth is in just the right place so that it's lined up with respect to the sun, and both hemispheres of the planet receive the same amount of daylight. On these days, there are almost equal amounts of day and night, which is where the word equinox — meaning "equal night" in Latin — comes from. The equinox marks the onset of spring with a transition from shorter to longer days for half the planet, along with more direct sunlight as the sun rises higher above the horizon. In 2017, in the Northern Hemisphere, the spring equinox occurs on March 20. Six months later, fall begins with the autumnal equinox on Sept. 22.


Image above: During the equinoxes, both hemispheres receive equal amounts of daylight. Image Credits: NASA's Goddard Space Flight Center/Genna Duberstein.

Solstice

As Earth continues along in its orbit after the equinox, it eventually reaches a point where its tilt is at the greatest angle to the plane of its orbit — and the point where one half of the planet is receiving the most daylight and the other the least. This point is the solstice — meaning “sun stands still” in Latin — and it occurs twice a year. These days are our longest and shortest days, and mark the change of seasons to summer and winter.


Image above: During the solstices, Earth reaches a point where its tilt is at the greatest angle to the plane of its orbit, causing one hemisphere to receive more daylight than the other. Image Credits: NASA's Goddard Space Flight Center/Genna Duberstein.

Full Moon and New Moon

As Earth goes around the sun, the moon is also going around Earth. There is a point each month when the three bodies align with Earth between the sun and the moon.  During this phase, viewers on Earth can see the full face of the moon reflecting light from the sun — a full moon. The time between full moons is about four weeks — 29.5 days to be exact. Halfway between full moons, the order of the three bodies reverses and the moon lies between the sun and Earth. During this time, we can't see the moon reflecting the sun's light, so it appears dark. This is the new moon.


Image above: When the moon, on its orbit around Earth, reaches the point farthest from the sun, we see a full moon. When the moon is on the side closest to the sun we can't see the moon reflecting the sun's light, so it appears dark. This is the new moon. Image Credits: NASA's Goddard Space Flight Center/Genna Duberstein.

Lunar Eclipse

Sometimes, during a full moon, Earth lines up perfectly between the moon and the sun, so its shadow is cast on the moon. From Earth's viewpoint, we see a lunar eclipse. The plane of the moon’s orbit around Earth isn’t precisely aligned with the plane of the Earth’s orbit around the sun so on most months we don't see an eclipse. The next lunar eclipse — which will be visible throughout much of Asia, Europe, Africa and Australia — will occur on Aug. 7.


Image above: When the moon falls completely in Earth’s shadow, a total lunar eclipse occurs. Only light travelling through Earth’s atmosphere, which is bent into the planet’s shadow, is reflected off the moon, giving it a reddish hue. Image Credits: NASA's Goddard Space Flight Center/Genna Duberstein.

Solar Eclipse

A solar eclipse happens when the moon blocks our view of the sun. This can only happen at a new moon, when the moon's orbit positions it between the sun and Earth — but this doesn't happen every month. As mentioned above, the plane of the moon’s orbit around Earth isn’t precisely aligned with the plane of the Earth’s orbit around the sun so, from Earth's view, on most months we see the moon passing above or below the sun. A solar eclipse happens only on those new moons where the alignment of all three bodies are in a perfectly straight line.

When the moon blocks all of the sun’s light, a total eclipse occurs, but when the moon is farther away — making it appear smaller from our vantage point on Earth — it blocks most, but not all of the sun.  This is called an annular eclipse, which leaves a ring of the sun’s light still visible from around the moon. This alignment usually occurs every year or two, but is only visible from a small area on Earth.

On Aug. 21, a total solar eclipse will move across America. While lunar eclipses are visible from entire hemispheres of Earth, a total solar eclipse is visible only from a narrow band along Earth’s surface. Since this eclipse will take about an hour and a half to cross an entire continent, it is particularly important scientifically, as it allows observations from many places for an extended duration of time. NASA has funded 11 projects to take advantage of the 2017 eclipse and study its effects on Earth as well as study the sun’s atmosphere.


Image above: When the moon’s orbit around Earth lines up on the same plane as Earth’s orbit around the sun, its shadow is cast across the planet. Image Credits: NASA's Goddard Space Flight Center/Genna Duberstein.

Transits

An eclipse is really just a special kind of transit — which is when any celestial body passes in front of another. From Earth we are able to watch transits such as Mercury and Venus passing in front of the sun. But such transits also offer a way to spot new distant worlds. When a planet in another star system passes in front of its host star, it blocks some of the star’s light — making it appear slightly dimmer. By watching for changes in the amount of light over time, we can deduce the presence of a planet. This method has been used to discover thousands of planets, including the TRAPPIST-1 planets.  


Image above: During a transit, a planet passes in between us and the star it orbits. This method is commonly used to find new exoplanets in our galaxy. Image Credits: NASA's Goddard Space Flight Center/Genna Duberstein.

For more information about how NASA looks at these events, visit: http://www.nasa.gov/sunearth

Related links:

NASA 11 projects: https://www.nasa.gov/feature/goddard/2017/eclipse-2017-nasa-supports-a-unique-opportunity-for-science-in-the-shadow

Eclipses and Transits: http://www.nasa.gov/topics/solarsystem/features/eclipse/index.html

Solar System: https://www.nasa.gov/topics/solarsystem/index.html

Images (mentioned), Text, Credits: NASA’s Goddard Space Flight Center, by Mara Johnson-Groh/Rob Garner.

Best regards, Orbiter.ch

Raising the (G)bar for antimatter exploration












CERN - European Organization for Nuclear Research logo.

 March 18, 2017

The absence of antimatter in the universe is a long-standing jigsaw puzzle in physics. Many experiments have been exploring this question by finding asymmetries between particles and their antimatter counterparts.

GBAR (Gravitational Behaviour of Antihydrogen at Rest), a new experiment at CERN, is preparing to explore one aspect of this puzzle – what is the effect of gravity on antimatter? While theories exist as to whether antimatter will behave like matter or not, a definitive experimental result is still missing.



Image above: Installation of the GBAR linac in its shielding bunker. The electrons accelerated to 10 MeV toward a target will produce the positrons that are necessary to form antihydrogen with the antiprotons coming from the ELENA decelerator. (Image: Max Brice/CERN).


GBAR will measure the effect of gravity on antihydrogen atoms. Located in the Antiproton Decelerator (AD) hall, GBAR is the first of five experiments that will be connected to the new ELENA deceleration ring. On 1 March, the first component of the experiment was installed – a linear accelerator (linac). In sharp contrast to the LHC’s chain of big accelerators and fast particles, the AD world of antimatter is small and its particles are as slow as they come. The GBAR linac is only 1.2 metres long and it will be used to create positrons, the antimatter equivalent of electrons.

The experiment will use antiprotons supplied by ELENA and positrons created by the linac to produce antihydrogen ions. They consist of one antiproton and two positrons, and their positive charge makes them significantly easier to manipulate. With the help of lasers, their velocity will be reduced to half a metre per second. This will allow them to be directed to a fixed point. Then, trapped by an electric field, one of their positrons will be removed with a laser, which will make them neutral again. The only force acting on them at this point will be gravity and they will be free to make a 20-centimetre fall, during which researchers will observe their behaviour.

The results might turn out to be very exciting. As the spokesperson of GBAR, Patrice Pérez, explains: “Einstein’s Equivalence Principle states that the trajectory of a particle is independent of its composition and internal structure when it is only submitted to gravitational forces. If we find out that gravity has a different effect on antimatter, this would mean that we still have a lot to learn about the universe.”

Five other experiments are based at the Antiproton Decelerator, two of which – AEGIS and ALPHA – are also studying the effect of gravity on antimatter.

Note:

CERN, the European Organization for Nuclear Research, is one of the world’s largest and most respected centres for scientific research. Its business is fundamental physics, finding out what the Universe is made of and how it works. At CERN, the world’s largest and most complex scientific instruments are used to study the basic constituents of matter — the fundamental particles. By studying what happens when these particles collide, physicists learn about the laws of Nature.

The instruments used at CERN are particle accelerators and detectors. Accelerators boost beams of particles to high energies before they are made to collide with each other or with stationary targets. Detectors observe and record the results of these collisions.

Founded in 1954, the CERN Laboratory sits astride the Franco–Swiss border near Geneva. It was one of Europe’s first joint ventures and now has 22 Member States.

Related links:

GBAR (Gravitational Behaviour of Antihydrogen at Rest): https://gbar.web.cern.ch/GBAR/public/index.html

Antiproton Decelerator (AD): https://home.cern/about/accelerators/antiproton-decelerator

ELENA: http://home.cern/about/updates/2016/11/new-ring-slow-down-antimatter

linear accelerator (linac): http://home.cern/tags/linear-accelerator

AEGIS: http://home.cern/about/experiments/aegis

ALPHA: https://home.cern/about/experiments/alpha

For more information about European Organization for Nuclear Research (CERN), Visit: http://home.cern/

Image (mentioned), Text, Credits: CERN/Iva Raynova.

Greetings, Orbiter.ch

LHCb observes an exceptionally large group of particles












CERN - European Organization for Nuclear Research logo.

March 18, 2017

The LHCb experiment at CERN is a hotbed of new and outstanding physics results. In just the last few months, the collaboration has announced the measurement of a very rare particle decay and evidence of a new manifestation of matter-antimatter asymmetry, to name just two examples.


Image above: A typical LHCb event fully reconstructed. Particles identified as pions, kaon, etc. are shown in different colours. (Image: LHCb collaboration).

In a paper released today, the LHCb collaboration announced the discovery of a new system of five particles all in a single analysis. The exceptionality of this discovery is that observing five new states all at once is a rather unique event.

The particles were found to be excited states – a particle state that has a higher energy than the absolute minimum configuration (or ground state) – of a particle called "Omega-c-zero", Ωc0. This Ωc0 is a baryon, a particle with three quarks, containing two “strange” and one “charm” quark. Ωc0 decays via the strong force into another baryon, called "Xi-c-plus", Ξc+ (containing a “charm”, a “strange” and an “up” quark) and a kaon K-. Then the Ξc+ particle decays in turn into a proton p, a kaon K- and a pion π+.

From the analysis of the trajectories and the energy left in the detector by all the particles in this final configuration, the LHCb collaboration could trace back the initial event – the decay of the Ωc0 – and its excited states. These particle states are named, according to the standard convention, Ωc(3000)0, Ωc(3050)0, Ωc(3066)0, Ωc(3090)0 and Ωc(3119)0. The numbers indicate their masses in megaelectronvolts (MeV), as measured by LHCb.


Image above:  The image above shows the data (black dots) of the reconstructed mass distribution resulting from the combination of the Ξc+ and K- particles. The five particle states are the five narrow peaks standing out from the distribution of data. (Image: LHCb collaboration).

This discovery was made possible thanks to the specialised capabilities of the LHCb detector in the precise recognition of different types of particles and also thanks to the large dataset accumulated during the first and second runs of the Large Hadron Collider. These two ingredients allowed the five excited states to be identified with an overwhelming level of statistical significance – meaning that the discovery cannot be just a statistical fluke of data.

The next step will be the determination of the quantum numbers of these new particles – characteristic numbers used to identify the properties of a specific particle – and the determination of their theoretical significance. This discovery will contribute to understanding how the three constituent quarks are bound inside a baryon and also to probing the correlation between quarks, which plays a key role in describing multi-quark states, such as tetraquarks and pentaquarks.

More information on this result can be found on the LHCb website and in the scientific paper: https://arxiv.org/abs/1703.04639

Note:

CERN, the European Organization for Nuclear Research, is one of the world’s largest and most respected centres for scientific research. Its business is fundamental physics, finding out what the Universe is made of and how it works. At CERN, the world’s largest and most complex scientific instruments are used to study the basic constituents of matter — the fundamental particles. By studying what happens when these particles collide, physicists learn about the laws of Nature.

The instruments used at CERN are particle accelerators and detectors. Accelerators boost beams of particles to high energies before they are made to collide with each other or with stationary targets. Detectors observe and record the results of these collisions.

Founded in 1954, the CERN Laboratory sits astride the Franco–Swiss border near Geneva. It was one of Europe’s first joint ventures and now has 22 Member States.

Related links:

LHCb website: http://lhcb-public.web.cern.ch/lhcb-public/Welcome.html#Omega_c

Large Hadron Collider (LHC): http://home.cern/topics/large-hadron-collider

For more information about European Organization for Nuclear Research (CERN), Visit: http://home.cern/

Images (mentioned), Text, Credits: CERN/Stefania Pandolfi.

Best regards, Orbiter.ch

vendredi 17 mars 2017

SAGE III Achieves First Light from Space Station Perch












ISS - International Space Station patch.

March 17, 2017

The Stratospheric Aerosol and Gas Experiment III, or SAGE III, reached another in a series of major recent milestones Friday, March 17, by collecting first light data from its new home on the International Space Station.

In an email sent to SAGE III team members early Friday afternoon, acting SAGE III Project Manager Joe Gasbarre said, “After the mission operations and science teams had a chance early this morning to review the data received overnight, it was clear several successful solar occultations occurred, thus proving First Light had been achieved on the instrument.”

SAGE III Scan Head Range of Motion Test

Video above: On March 16, the scan head of the Stratospheric Aerosol and Gas Experiment III, or SAGE III, on the International Space Station completed a range-of-motion test. Several hours later, the instrument collected first light data. Video Credit: NASA.

Solar occultation is a type of measurement that involves looking at the light from the sun as it passes through Earth’s atmosphere at the edge, or limb, of the planet. SAGE III uses both solar and lunar occultation to measure ozone and aerosols in Earth’s atmosphere.

Autonomous operations of the instrument will continue over the weekend. Next week, the mission operations team will settle into what Gasbarre referred to as a “cadence of adjustments and data analysis” as instrument commissioning moves into full swing. Complete commissioning and calibration of SAGE III will take approximately 90 days.

International Space Station (ISS). Image Credit: NASA

The SAGE III mission operations team is based at the Flight Mission Support Center at NASA’s Langley Research Center in Hampton, Virginia.

“I cannot say enough about the efforts of this entire team stretching back many years,” said Gasbarre in his email. “This success is only possible due to the hard work, sacrifice and support of the entire team as well as our stakeholders.”


Image above: The SAGE III mission operations team in the Flight Mission Support Center at NASA's Langley Research Center in Hampton, Virginia. Image Credits: NASA/David C. Bowman.

Once fully commissioned, SAGE III will take occultation measurements about 15 or 16 times a day. The space station’s unique orbital path will allow SAGE III to make observations during all seasons and over a large portion of the globe.

SAGE III launched to the station Feb. 19 from Kennedy Space Center in Florida aboard a SpaceX Falcon 9/Dragon spacecraft. Following docking of the Dragon capsule, the station’s robotic Canadarm2 removed the SAGE III instrument payload and its Nadir Viewing Platform and installed them on the station. Installation was completed March 7.

Related links:

Earth: https://www.nasa.gov/topics/earth/index.html

Ozone: https://www.nasa.gov/ozone

Space Station Research and Technology: https://www.nasa.gov/mission_pages/station/research/index.html

International Space Station (ISS): https://www.nasa.gov/mission_pages/station/main/index.html

Images (mentioned), Video (mentioned), Text, Credits: NASA’s Langley Research Center/Joe Atkinson.

Greetings, Orbiter.ch

Layered Deposits in Uzboi Vallis












NASA - Mars Reconnaissance Orbiter (MRO) patch.

March 17, 2017


Layered deposits in Uzboi Vallis sometimes occur in alcoves along the valley and/or below where tributaries enter it. These deposits may record deposition into a large lake that once filled Uzboi Vallis when it was temporarily dammed at its northern end by the rim Holden Crater and before it was overtopped and breached allowing water to drain back out of the valley.

Layered deposits similar to those here may remain preserved where they were protected from erosion during drainage of the lake. Data from the CRISM instrument onboard MRO shows that clays are within these deposits that may differ from clays found elsewhere on the valley floor. Hence, the clays in these layers may have been washed into the lake from surrounding clay-bearing surfaces.

This is a stereo pair with http://www.uahirise.org/PSP_008338_1525

The map is projected here at a scale of 50 centimeters (19.7 inches) per pixel. [The original image scale is 52.8 centimeters (20.8 inches) per pixel (with 2 x 2 binning); objects on the order of 158 centimeters (62.2 inches) across are resolved.] North is up.

The University of Arizona, Tucson, operates HiRISE, which was built by Ball Aerospace & Technologies Corp., Boulder, Colo. NASA's Jet Propulsion Laboratory, a division of Caltech in Pasadena, California, manages the Mars Reconnaissance Orbiter Project for NASA's Science Mission Directorate, Washington.

Mars Reconnaissance Orbiter (MRO): http://www.nasa.gov/mission_pages/MRO/main/index.html

Image, Text, Credits: NASA/Tony Greicius/JPL-Caltech/Univ. of Arizona.

Greetings, Orbiter.ch

New Hubble mosaic of the Orion Nebula












ESA - Hubble Space Telescope logo.

17 March 2017

Hunting for rogue planets and runaway stars

New Hubble image of Kleinmann-Low Nebula

In the search for rogue planets and failed stars astronomers using the NASA/ESA Hubble Space Telescope have created a new mosaic image of the Orion Nebula. During their survey of the famous star formation region, they found what may be the missing piece of a cosmic puzzle; the third, long-lost member of a star system that had broken apart.

The Orion Nebula is the closest star formation region to Earth, only 1400 light-years away. It is a turbulent place — stars are being born, planetary systems are forming and the radiation unleashed by young massive stars is carving cavities in the nebula and disrupting the growth of smaller, nearby stars.

Because of this ongoing turmoil, Hubble has observed the nebula many times to study the various intriguing processes going on there. This large composite image of the nebula’s central region, combining visual and near-infrared data, is the latest addition to this collection.

Ground-based image of Orion, Canis Minor and Canis major (ground-based image)

Astronomers used these new infrared data to hunt for rogue planets — free-floating in space without a parent star — and brown dwarfs in the Orion Nebula. The infrared capabilities of Hubble also allow it to peer through the swirling clouds of dust and gas and make the stars hidden within clearly visible; the unveiled stars appear with bright red colours in the final image. Among these, astronomers stumbled across a star moving at an unusually high speed — about 200 000 kilometres per hour [1]. This star could be the missing piece of the puzzle of a star system that had been broken apart 540 years ago.

Astronomers already knew about two other runaway stars in the Orion Nebula which were most likely once part of a now-defunct multiple-star system. For years it was suspected that the original system contained more than just these two stars. Now, by virtue of accident and curiosity, Hubble may have found the missing third piece of this cosmic puzzle.

Zoom-in on the Orion Nebula

Whether the new star is indeed the missing — and the last — piece of the puzzle will require further observations. So will the answer to the question of why the original star system broke apart in the first place. While there are several theories — interactions with other, nearby stellar groups, or two of the stars getting too close to each other — none can be ruled out or confirmed yet.

And while the astronomers are looking for the answers to these questions, who knows what mystery they will find next?

Notes:

[1] The relative speed of the star was calculated by comparing observations made in 1998 with the recent ones. The speed of the newly discovered star is almost 30 times the speed of most of the nebula’s stellar inhabitants.

More information:

The Hubble Space Telescope is a project of international cooperation between ESA and NASA.

Links:

Images of Hubble: http://www.spacetelescope.org/images/archive/category/spacecraft/

Hubblesite release: http://hubblesite.org/news_release/news/2017-11

Images, Text, Credits: NASA/ESA/Hubble/Akira Fujii/Video: Credit:ESA/Hubble, A. Fujii, M. Kornmesser/Music: Johan B. Monell (www.johanmonell.com).

Best regards, Orbiter.ch

Beautiful science with astronaut aurora












ISS - International Space Station logo.

17 March 2017

Some of the most wonderful pictures taken by astronauts from space are of aurora dancing over our planet. Now the photos are more than just pretty pictures thanks to an ESA project that makes them scientifically usable.

The Milky-Way and Aurora Australis

Aurora offer a visual means to study space weather, the conditions in the upper regions of our atmosphere. These colourful displays are produced when electrically charged particles from the Sun in the solar wind are channelled along Earth’s magnetic field lines and strike atoms high in the atmosphere.

Just as the Sun is instrumental to the weather on Earth, solar activity influences space weather, which in turn can interfere with radio transmissions, satellites and even our electricity supply.

From above and below - and straight through

Scientists study space weather and aurora using satellites such as ESA’s Cluster and Proba-2 but also through a network of cameras on the ground. These cameras are often obscured by cloud or snow and coverage from the southern hemisphere is poor because there is not much land at the best latitudes for observing the aurora.

 Thick green fog of aurora

Pictures taken from the International Space Station can provide context and add information by improving estimates of the height and length of aurora. Some reach 500 km high – meaning the Station sometimes flies right through them.

Looking to the stars to find out when an where

First, the images need to be turned into something that scientists can use. Most important is to know the exact time and where the camera was pointing.

The images are downloaded in the highest resolution and faulty camera pixels from cosmic radiation are removed. Software corrects distortion from the camera lens.

Geo-referencing astronauts' auroral photography to further their use in research

Just like 19th century explorers before navigation satellites existed, ESA’s team looked to the stars for reference, using software to identify the stars in the image, and from there calculate the precise position of each pixel and its scale.

Last, the image time is determined by linking cities with their calculated locations and the horizon.

Software engineer and ESA young graduate trainee Maik Riechert, who worked on the project, explains: “The ideal images for processing are pictures showing Earth and the stars with the horizon just above the middle.”

Putting it all together

When all the images are processed, the timelapse videos offer a way to check the process went smoothly. Any jitter or changes in star tracking will show up in the final video, so a smooth run proves that the individual images are ready for analysis.


Now it is over to the scientists who can use the extra information in their research. Find the full dataset on the automatic geo-referencing of astronaut auroral photography webpage. A paper describing the method is available here: http://www.geosci-instrum-method-data-syst.net/5/289/2016/

ESA’s Andrew Walsh, manager for this project, concludes “This project shows that nothing is wasted and you can get useful science from unusual sources.”

Related links:

International Space Station science reports: http://www.esa.int/Our_Activities/Human_Spaceflight/Columbus/ESA_ISS_Science_System_-_Operations_Status_Report_167_Increment_39_12_25_April_2014

International Space Station Benefits for Humanity: http://www.esa.int/Our_Activities/Human_Spaceflight/International_Space_Station_Benefits_for_Humanity

Erasmus Space Exhibition Centre: http://www.esa.int/Our_Activities/Human_Spaceflight/Research/Erasmus_Space_Exhibition_Centre

Images, Text, Credits: ESA/NASA/Animation courtesy of the Earth Science and Remote Sensing  Unit, NASA/JSC/Hirai Mamoru.

Best regards, Orbiter.ch

Japan launches spy satellite against Pyongyang










JAXA - Japan Aerospace Exploration Agency logo.

March 17, 2017

The launch took place from the Tanegashima Space Center (southwestern Japan)

This new satellite complements an intelligence gathering device to monitor the movements of North Korea.

Japan has placed a spy satellite in space on Friday, complementing an intelligence gathering system aimed at monitoring the movements of North Korea.

The launch took place as scheduled at 10:20 local time (01H20 GMT) with the 33rd H-2A rocket from Tanegashima base (southwestern Japan), according to live images on the NHK public channel. "The satellite has separated as planned, the mission is a success," a spokesman for the Japan Space Exploration Agency (Jaxa) told AFP.

Japan launches IGS Radar 5 spy satellite against Pyongyang

Due to the confidential nature of the mission carried out with Mitsubishi Heavy Industries (MHI), little information is given, except that it concerns the placement of an "information-gathering" radar satellite that joins A fleet already in place. It was the 33rd launches of the H-2A launcher, whose success rate now exceeds 97%. A single failure was deplored at the end of 2003 when he was due to orbit the first spy satellite of the device.

Surveillance imagined in the 90s

Several of the satellites of this nature launched since then have also suffered damage, but the whole is functional, with four operational and three replacements (the one sent this Friday and two others), half optical equipment and radar.

The surveillance of the North Korean neighbors' space had been imagined in the late 1990s because of the fears of North Korea, which had just been firing missiles. Since then, the Pyongyang regime has not calmed down, on the contrary, the threat has even intensified.

 IGS Radar satellite.Image Credits: p-island.com, S. Matsuura

On the orders of the leader Kim Jong-Un, the North Koreans fired on March 6 a salvo of ballistic missiles, three of which ended their race at sea near the Japanese archipelago. The ambition is to develop a ballistic intercontinental missile (ICBM) capable of carrying nuclear fire on the American continent.

Japan's spy satellites allow one-meter objects to be spotted on the ground at night, or through a cloudy ceiling, from an altitude of several hundred kilometers. They can also be used to collect data on the damage caused by natural disasters such as earthquakes, tsunamis or typhoons. The complete device is supposed to allow observing at least once a day each terrestrial zone.

In the future, the government plans to extend the fleet to 10 aircraft in order to have several views of the same land-based location on a daily basis.

For more information about Japan Aerospace Exploration Agency (JAXA), visit: http://global.jaxa.jp/

Images, Video, Text, Credits: Japan Aerospace Exploration Agency (JAXA)/AFP/p-island.com, S. Matsuura/Orbiter.ch Aerospace/Roland Berga.

Greetings, Orbiter.ch

jeudi 16 mars 2017

Symphonizing the Science: NASA Twins Study Team Begins Integrating Results












NASA - The Twins Study patch.

March 16, 2017

It begins with one instrument. Then another joins in. Before you know it a grand symphony is playing before your eyes. NASA Twins Study researchers are eager to integrate their results and create a symphony of science.

Preliminary findings were discussed during the Human Research Program Investigators’ Workshop in January, and now enthusiasm abounds as the integration process begins. The investigators are a unique group of researchers with different expertise associated with genetic and physiological areas of study.

While Scott Kelly spent a year in space aboard the space station, his identical twin brother, retired astronaut Mark Kelly, spent that year on Earth. Comparing the twins’ biological samples will yield important information on how spaceflight affects the human body. These trailblazing genetic studies will help NASA keep astronauts safe on a journey to Mars.

The symphony begins with data. Big data. The Twins Study was established as a multi-omics pilot study for sharing data. Typically, research is done individually and results are made public in scientific journals that kickoff discussions of findings. However, this study is different. From the start, the Twins Study investigators have planned to integrate their results before publishing.

Each investigation is like an instrument. On its own, it plays solo music. But put them all together and you have something incredible.


Image above: (Graphic) Symphonizing the Science: NASA Twins Study Team Begins Integrating Results Image Credit: NASA.

“The beauty of this study is when integrating rich data sets of physiological, neurobehavioral and molecular information, one can draw correlations and see patterns,” said Tejaswini Mishra, Ph.D., research fellow at Stanford University School of Medicine, who is creating the integrated database, recording results and looking for correlations. “No one has ever looked this deeply at a human subject and profiled them in this detail. Most researchers combine maybe two to three types of data but this study is one of the few that is collecting many different types of data and an unprecedented amount of information.”

The next step in the Twins Study is composing the symphony. As individual researchers analyze and compile their data they will be sharing their individual and integrative analyses with the Stanford team headed by Mike Snyder, Ph.D., who will apply different methods to further integrate it into big data sets and begin composing a masterful ensemble. After that, the investigators will begin to review the integrated data set to either confirm or modify their initial findings.

“There are a lot of firsts with this study and that makes it exciting,” said Brinda Rana, Ph.D., associate professor of psychiatry, University of California San Diego School of Medicine. “A comparative study with one twin in space and one on Earth has never been done before. Each investigation within the study complements the other.”

The researchers view the study as a new piece of music where they learn their individual parts and then join together with the conductor to play the musical score. Through the integration of data from biochemical markers, cognitive ability, gut bacterial composition, and biomolecules (DNA, RNA, proteins, metabolites), they hope to identify health-associated molecular effects of spaceflight to protect astronauts on future missions.

“The human systems in the body are all intertwined which is why we should view the data in a holistic way,” said Scott M. Smith, Ph.D., NASA manager for nutritional biochemistry at the Johnson Space Center. He conducts biochemical profiles on astronauts and his research is targeted to specific metabolites, end products of various biological pathways and processes.

“If we see protein changes then we can look at the RNA, and if we see RNA changes then we can look at the DNA, said Rana. “By integrating data we can make a timeline to give us an indication if it is a precursor or result of genetics. Does a specific gene regulate protein change or do other genes? Once we know we can establish cause and effect and use molecules to measure.”

Sometimes the science surprises us.

Susan Bailey, Ph.D., professor of radiation cancer biology and oncology, College of Veterinary Medicine and Biomedical Science, Colorado State University, received preliminary results contrary to her hypothesis. Telomeres shorten as we age so she expected to see Scott Kelly’s telomeres shorten after living in space almost a year. But to her surprise, the preliminary results showed an increase in average telomere length or an increase in the population of cells which have longer telomeres. Therefore, she is searching for mechanistic data to explain what she is seeing. To determine if it is an anomaly or not, she is looking at Scott’s exercise schedule, food logs and behavioral data. She also is looking at data from Andy Feinberg, M.D., M.P.H., director, Center of Epigenetics, Johns Hopkins University School of Medicine, who is analyzing methylation patterns, a major factor in gene regulation and gene expression, such as which genes are turned on and off.


Image above: Expedition 45/46 Commander, retired astronaut Scott Kelly (right) along with his twin brother, retired astronaut Mark Kelly (left) speak to media about the Twins Study and One-Year Mission. Image Credit: NASA.

Bailey will also look at data from Chris Mason, Ph.D., associate professor, Department of Physiology and Biophysics Weill Cornell Medicine, for mutations in the promoter region of the telomerase, to help form a correlation and confirm or refute her preliminary finding.

Mason said, “Both the universe and the human body are complicated systems and we are studying something hard to see. It’s like having a new flashlight that illuminates the previously dark gears of molecular interactions. It is a more comprehensive way to conduct research.”

“There is no doubt, the learnings from integrating our data will be priceless,” said Emmanuel Mignot, M.D., Ph.D., director of Center for Sleep Science and Medicine, Stanford University School of Medicine. He studies the immune system and is enthusiastic to study specific immune cell populations because many of the other immune studies focus only on general factors.

The orchestra is only warming up now. As the data from individual investigations start filtering into the integrated composition, researchers and NASA eagerly await the results. When the full score of integrated data is ready, the summary of results will be published in late 2017 or early 2018. After that, individual investigators will publish theme papers with more detailed findings of the various investigations. As NASA embarks on its next journey, the results of the Twins Study will provide a front-row seat in this grand performance of human exploration.

NASA's Human Research Program (HRP) is dedicated to discovering the best methods and technologies to support safe, productive human space travel. HRP enables space exploration by reducing the risks to human health and performance using ground research facilities, the International Space Station, and analog environments. This leads to the development and delivery of a program focused on: human health, performance, and habitability standards; countermeasures and risk mitigation solutions; and advanced habitability and medical support technologies. HRP supports innovative, scientific human research by funding more than 300 research grants to respected universities, hospitals and NASA centers to over 200 researchers in more than 30 states.

Related article:

How Stressful Will a Trip to Mars Be on the Human Body? We Now Have a Peek Into What the NASA Twins Study Will Reveal
http://orbiterchspacenews.blogspot.ch/2017/01/how-stressful-will-trip-to-mars-be-on.html

Related links:

NASA's Human Research Program (HRP): http://www.nasa.gov/hrp

Twins Study investigators: https://www.nasa.gov/twins-study/research

Journey to Mars: https://www.nasa.gov/topics/journeytomars/index.html

One-Year Crew: https://www.nasa.gov/content/one-year-crew/index.html

Space Station Research and Technology: https://www.nasa.gov/mission_pages/station/research/index.html

International Space Station (ISS): https://www.nasa.gov/mission_pages/station/main/index.html

Image (mentioned), Text, Credits: NASA Human Research Engagement & Communications/Amy Blanchett/Laurie Abadie/Timothy Gushanas.

Best regards, Orbiter.ch

SpaceX’s Falcon 9 successfully delivered EchoStar XXIII to a Geostationary Transfer Orbit











SpaceX - Falcon 9 / EchoStar XXIII Mission patch.

March 16, 2017


Image above: Falcon 9 lifted off from Launch Complex 39A at NASA’s Kennedy Space Center at 2:00 am EDT, 6:00 am UTC.

On March 16, 2017, SpaceX’s Falcon 9 successfully delivered EchoStar XXIII, a commercial communications satellite for EchoStar Corporation, to a Geostationary Transfer Orbit (GTO).

EchoStar XXIII

EchoStar XXIII is a highly flexible, Ku-band broadcast satellite services (BSS) satellite with four main reflectors and multiple sub-reflectors supporting multiple mission profiles. Initial commercial deployment of EchoStar XXIII will be at 45° West, and the Satellite End of Life (EOL) Power is 20 kilowatts (kW).

Liftoff! SpaceX launches Echostar XXIII communications satellite

Below is a summary of the mission in photos:


Image above: View of the engine end of the Falcon 9 first stage as the vehicle powers EchoStar XXIII to orbit.


Image above: Following a nearly 18 minute coast phase, the second stage engine relights to provide the final boost for the EchoStar XXIII satellite.


Image above: View of the EchoStar XXIII satellite as it deploys from the Falcon 9 second stage.

For more information about SpaceX, visit: http://www.spacex.com/

Images, Video, Text, Credits: SpaceX/Günter Space Page.

Best regards, Orbiter.ch

NASA Satellite Identifies Global Ammonia ‘Hotspots’












NASA - EOS Aqua Mission logo.

March 16, 2017

Study ties fertilizers, animal waste, changes to atmospheric chemistry and climate change to increased ammonia over the United States, Europe, China and India


Image above: Global atmospheric ammonia trends measured from space from 2002 to 2016. Hot colors represent increases from a combination of increased fertilizer application, reduced scavenging by acid aerosols and climate warming. Cool colors show decreases due to reduced agricultural burning or fewer wildfires. Image Credits: Juying Warner/GRL.

The first global, long-term satellite study of airborne ammonia gas has revealed “hotspots” of the pollutant over four of the world’s most productive agricultural regions. The results of the study, conducted using data from NASA’s Atmospheric Infrared Sounder (AIRS) instrument on NASA’s Aqua satellite, could inform the development of strategies to control pollution from ammonia and ammonia byproducts in Earth’s agricultural areas.

A University of Maryland-led team discovered steadily increasing ammonia concentrations from 2002 to 2016 over agricultural centers in the United States, Europe, China and India. Increased concentrations of atmospheric ammonia are linked to poor air and water quality.  

The NASA-funded study, published March 16 in Geophysical Research Letters, describes probable causes for the observed increased airborne ammonia concentrations in each region. Although specifics vary between areas, the increases are broadly tied to crop fertilizers, livestock animal wastes, changes to atmospheric chemistry, and warming soils that retain less ammonia.

“Measuring ammonia from the ground is difficult, but the satellite-based method we have developed allows us to track ammonia efficiently and accurately, said Juying Warner, University of Maryland associate research scientist in atmospheric and oceanic science. “We hope that our results will help guide better management of ammonia emissions.”

AIRS, in conjunction with the Advanced Microwave Sounding Unit (AMSU) also on Aqua, senses emitted infrared and microwave radiation from Earth to provide a 3-D look at our planet's weather and climate. Working in tandem, the instruments make simultaneous observations down to Earth's surface, even in the presence of heavy clouds. With more than 2,000 channels sensing different regions of the atmosphere, the system creates a global, 3-D map of atmospheric temperature and humidity, cloud amounts and heights, concentrations of selected greenhouse and other trace gases, and many other atmospheric phenomena.

"AIRS wasn’t designed to observe ammonia, but the instrument sensitivity and stability have allowed us to monitor ammonia trends,” said AIRS Project Scientist Eric Fetzer of NASA’s Jet Propulsion Laboratory, Pasadena, California. “The unexpected large ammonia increase is one example of rapid atmospheric changes from human activities that AIRS is observing."

Gaseous ammonia is a natural part of Earth’s nitrogen cycle, but excess ammonia is harmful to plants and reduces air and water quality. In the troposphere -- the lowest, most dense part of the atmosphere where all weather takes place and where people live -- ammonia gas reacts with nitric and sulfuric acids to form nitrate-containing particles. Those particles contribute to aerosol pollution that is damaging to human health. Ammonia gas can also fall back to Earth and enter lakes, streams and oceans, where it contributes to harmful algal blooms and “dead zones” with dangerously low oxygen levels.

“Little ammonia comes from tailpipes or smokestacks. It’s mainly agricultural, from fertilizer and animal husbandry,” said co-author and University of Maryland professor Russell Dickerson. “It has a profound effect on air and water quality -- and ecosystems.”

Each major agricultural region highlighted in the study experienced a slightly different combination of factors that correlate with increased ammonia in the air from 2002 to 2016.

The United States, for example, has not experienced a dramatic increase in fertilizer use or major changes in fertilizer application practices. But the study authors found that successful legislation to reduce acid rain in the early 1990s most likely had the unintended effect of increasing gaseous ammonia. The acids that cause acid rain also scrub ammonia gas from the atmosphere, and so the sharp decrease in these acids in the atmosphere is the most plausible explanation for the increase in ammonia over the same time frame.

Europe experienced the least dramatic increase in atmospheric ammonia of the major agricultural areas studied. The researchers suggest this is due in part to successful limits on ammonia-rich fertilizers and improved practices for treating animal waste. Much like the United States, a major potential cause for increased ammonia traces back to reductions in atmospheric acids that would normally remove ammonia from the atmosphere.

“The decrease in acid rain is a good thing. Aerosol loading has plummeted -- a substantial benefit to us all,” Dickerson said. “But it has also increased gaseous ammonia loading, which we can see from space.”

In China, a complex interaction of factors is tied to increased atmospheric ammonia. The authors suggest efforts to limit sulfur dioxide -- a key precursor of sulfuric acid, one of the acids that scrubs ammonia from the atmosphere -- could be partially responsible. But China has also greatly expanded agricultural activities since 2002, widening its use of ammonia-containing fertilizers and increasing ammonia emissions from animal waste. Warming of agricultural soils, due at least in part to global climate change, could also contribute.

Artist's view of Aqua satellite. Image Credit: NASA

“The increase in ammonia has spiked aerosol loading in China. This is a major contributor to the thick haze seen in Beijing during the winter, for example,” Warner said. “Also, meat is becoming a more popular component of the Chinese diet. As people shift from a vegetarian to a meat-based diet, ammonia emissions will continue to go up.”

In India, a broad increase in fertilizer use coupled with large contributions from livestock waste have resulted in the world’s highest concentrations of atmospheric ammonia. But the researchers note that ammonia concentrations have not increased nearly as quickly as over other regions. The study authors suggest that this is most likely due to increased emissions of acid rain precursors and, consequently, some increased scrubbing of ammonia from the atmosphere. This leads to increased levels of haze, a dangerous trend confirmed by other NASA satellite instruments, Dickerson said.

In all regions, the researchers attributed some of the increase in atmospheric ammonia to climate change, reflected in warmer air and soil temperatures. Ammonia vaporizes more readily from warmer soil, so as the soils in each region have warmed year by year, their contributions to atmospheric ammonia have also increased since 2002. The study also ascribes some ammonia fluctuations to wildfires, but these events are sporadic and unpredictable. As such, the authors excluded wildfires in their current analysis.

“This analysis has provided the first evidence for some processes we suspected were happening in the atmosphere for some time,” Warner said. “We would like to incorporate data from other sources in future studies to build a clearer picture.”

AIRS was built and is managed by JPL. Aqua is managed by NASA's Goddard Space Flight Center, Greenbelt, Maryland. For more on AIRS, visit: http://airs.jpl.nasa.gov

Aqua Satellite: https://www.nasa.gov/mission_pages/aqua/index.html

Images (mentioned), Text, Credits: NASA/Tony Greicius/JPL/Alan Buis/University of Maryland/Matthew Wright.

Greetings, Orbiter.ch

NASA Says Goodbye to a Pathfinder Earth Satellite After 17 Years











NASA - Earth Observing-1 Mission logo.

March 16, 2017

The first to map active lava flows from space.

The first to measure a facility’s methane leak from space.

The first to track re-growth in a partially logged Amazon forest from space.


After 17 years in orbit, one of NASA’s pathfinder Earth satellites for testing new satellite technologies and concepts comes to an end on March 30, 2017. The Earth Observing-1 (EO-1) satellite will be powered off on that date but will not enter Earth’s atmosphere until 2056.


Image above: This image taken by EO-1’s Advanced Land Imager on Feb. 10, 2012, shows an underwater volcanic eruption off El Hierro Island in the Atlantic Ocean. Image Credits: NASA's Earth Observatory.

Launched on Nov. 21, 2000, EO-1 was designed as a technology validation mission focused on testing cutting-edge satellite and instrument technologies that could be incorporated into future missions. Commissioned as part of NASA’s New Millennium Program, the satellite was part of a series of missions that were developed at a cheaper price tag to test new technologies and concepts that had never been flown before.

“EO-1 has changed the way spectral Earth measurements are being made and used by the science community,” said Betsy Middleton, EO-1’s Project Scientist at NASA's Goddard Space Flight Center in Greenbelt, Maryland.


Image above: This image taken by EO-1’s Advanced Land Imager (ALI) on Jan. 20, 2017, shows snowcap of the volcanic Mount Kilimanjaro. Image Credits: NASA's Earth Observatory.

EO-1 was launched with 13 new technologies, including three new instruments.  EO-1’s most important technology goal was to validate the Advanced Land Imager (ALI) for future Earth-observing satellites. The ALI provided a variety of Earth data including observations of forest cover, crops, coastal waters and aerosols. The ALI’s instrument design and onboard technology directly shaped the design of the Operational Land Imager (OLI) on Landsat 8, currently in orbit.

EO-1’s other key instrument is a hyperspectral instrument called Hyperion that allows scientists to see chemical constituents of Earth’s surface in fine detail with hundreds of wavelengths. These data allow scientists to identify specific minerals, track vegetation type and vigor of forests and monitor volcanic activity. The knowledge acquired and technology developed from Hyperion is being incorporated into a NASA concept for a potential future hyperspectral satellite, the Hyperspectral Infrared Imager, that will study the world’s ecosystems, such as identifying different types of plants and assessing wildfires and droughts.

With both of these instruments, the EO-1 team was able to acquire images with high spatial resolution of events and natural disasters around the world for anyone who requested it. The EO-1 team could point the instruments at any specific location and gather images every two to five days of a particular spot, which was very useful for scientists as well as disaster relief managers trying to stay informed of rapidly changing events. (Landsat typically looks at the same area once every 16 days.) EO-1 captured scenes such as the ash after the World Trade Center attacks, the flooding in New Orleans after Hurricane Katrina, volcanic eruptions and a large methane leak in southern California.


Image above: This artists sketch shows the Earth Observing-1 satellite over Earth. Image Credits: NASA/Goddard/SVS.

EO-1 also served as a valuable pathfinder for a variety of space technologies. Technologists installed and tested autonomy software on EO-1 that allowed the satellite to make its own decisions based on the content of the data it collected. For instance, if a scientist instructed EO-1 to take a picture of an area where a volcano was currently erupting, the software could decide to automatically take a follow-up image the next time it passed over the location.

The mission also validated software that allowed “formation flying” that kept EO-1 orbiting Earth exactly one minute behind the Landsat-7 satellite, already in orbit. The original purpose was to validate the new ALI technologies for use in Landsat 8, which was accomplished.

EO-1 was originally only supposed to last one year, but after that initial mission, the satellite had no major issues or breakdowns. On a shoestring budget contributed by NASA, the U.S. Geological Survey, the National Oceanic and Atmospheric Administration, National Reconnaissance Office and Naval Research Laboratory, the satellite continued to operate for sixteen more years, resulting in more than 1,500 papers published on EO-1 research.

On March 30, 2017, the satellite will be decommissioned, drained of its energy and become inert. Without enough fuel to keep EO-1 in its current orbit, the mission team will shut down the satellite and wait for it to return to Earth. When EO-1 does reenter the earth’s atmosphere in about 39 years, it is estimated that all the components will burn up in the atmosphere.

“We’ll probably just see EO-1 as a streak in the sky as it disintegrates,” said Middleton.

Related:

Hyperspectral Infrared Imager: https://hyspiri.jpl.nasa.gov/

For more information about EO-1 visit:

https://eo1.gsfc.nasa.gov/ or https://eospso.nasa.gov/missions/earth-observing-1

Images (mentioned), Text, Credits: NASA’s Goddard Space Flight Center, by Kasha Patel/Karl Hille.

Greetings, Orbiter.ch

Pan Anaglyph (3-D)










NASA - Cassini International logo.

March 16, 2017


These stereo views, or anaglyphs, highlight the unusual, quirky shape of Saturn's moon Pan. They appear three-dimensional when viewed through red-blue glasses with the red lens on the left.

The views show the northern and southern hemispheres of Pan, at left and right, respectively. They have been rotated to maximize the stereo effect.

Standard (non-stereo) versions of these views are presented in PIA21436.

Pan has an average diameter of 17 miles (28 kilometers). The moon orbits within the Encke Gap in Saturn's A ring. See PIA09868 and PIA11529 for more distant context views of Pan.

Both of these views look toward Pan's trailing side, which is the side opposite the moon's direction of motion as it orbits Saturn.

These views were acquired by the Cassini narrow-angle camera on March 7, 2017, at distances of approximately 16,000 miles or 25,000 kilometers (left view) and 21,000 miles or 34,000 kilometers (right view).

Image scale in the original images is about 500 feet (150 meters) per pixel (left view) and about 650 feet (200 meters) per pixel (right view). The images have been magnified by a factor of two from their original size.

For other 3-D images from the Cassini mission, see http://go.nasa.gov/2mudxQA.

The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington, D.C. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging operations center is based at the Space Science Institute in Boulder, Colo.

Related article:

Cassini Reveals Strange Shape of Saturn's Moon Pan
http://orbiterchspacenews.blogspot.ch/2017/03/cassini-reveals-strange-shape-of.html

Related links:

PIA21436: http://photojournal.jpl.nasa.gov/catalog/PIA21436

PIA09868: http://photojournal.jpl.nasa.gov/catalog/PIA09868

PIA11529: http://photojournal.jpl.nasa.gov/catalog/PIA11529

For more information about the Cassini-Huygens mission visit http://www.nasa.gov/cassini and http://saturn.jpl.nasa.gov/. The Cassini imaging team homepage is at http://ciclops.org and ESA's website http://www.esa.int/Our_Activities/Space_Science/Cassini-Huygens

Image, Text, Credits: NASA/Tony Greicius/JPL/Space Science Institute.

Greetings, Orbiter.ch