vendredi 10 février 2017

Quark Matter 2017: understanding the early universe












CERN - European Organization for Nuclear Research logo.

10 Feb 2017

Geneva and Chicago, 9 February 2017. This week the LHC experiment collaborations presented their latest results at the Quark Matter 2017 conference on how matter behaved in the very early moments of the universe.

Each year a special heavy ion run of CERN’s Large Hadron Collider provides collisions with lead nuclei, recreating conditions similar to those just after the big bang. Such collisions generate temperatures more than 100,000 times hotter than the centre of the Sun and allow researchers to study a state of matter called the “quark-gluon plasma". Under the extreme conditions created, protons and neutrons that make up the lead ions "melt", freeing quarks from their bonds with the gluons. Studying the quark-gluon plasma, and how it expands and cools, is important as it can help explain how it progressively gave rise to the particles that make up our universe today. It is also essential to understand the theory of the strong interactions known as Quantum Chromodynamics (QCD), which is the fundamental force describing the interactions between quarks and gluons.

"Quark matter demonstrates the wealth of physics results on a topic which is inherently very complex, heavy ionphysics,” said Eckhard Elsen, CERN Director for Research and Computing. "With the LHC performing so well and in so many different beam constellations, we have the experimental tools at hand to shed light on the state of matter that dominated in the early beginning of our universe.”

ALICE Heavy Ion Event Displays - 25 November 2015. (Image: CERN)

Individual heavy ion collisions create only a small droplet of quark-gluon plasma; the multitude of tracks left by the particle collisions allows scientists to look at how particles behave in such a medium. As an example, among the new results presented, the ALICE collaboration has shown that heavy quarks directly “feel” the shape and size of the quark-gluon-plasma droplet created within the region of the collision. This means that even the heaviest quarks move with the plasma, which is primarily formed of light quarks and gluons. ALICE also presented new results on the distribution of particle species – e.g. pions and kaons, among a zoo of other particles – in collisions of lead nuclei that help to measure the pressure and density in the quark-gluon plasma.

Particles are also used as direct probes to measure characteristics of the plasma. This is done by different means such as precision measurements of the energy loss of particles travelling through the plasma – a phenomenon known as jet quenching. ALICE, ATLAS and CMS all presented new results in this area at a new lead collision energy per nucleon pair of 5 TeV. These have been compared to previous measurements at the collision energy of 2.76 TeV. Significant progress has been made on jet quenching with many new results reported at the Quark Matter 2017 conference.

All of the LHC experiments now collect large samples of collisions of lead nuclei and lead nuclei with protons. The ATLAS and CMS collaborations presented key features of collective particle behaviour in high-multiplicity collisions, which are key to better understanding the microscopic mechanisms at play in the quark-gluon plasma, as well as new methods for measuring the collective effects in small systems. The LHCb collaboration also presented its first public result from fixed-target collisions with argon – a completely new programme at the LHC also allowing for very high energy density where, again, particles containing heavy-quarks exquisitely reconstructed in their detector, play an important role.

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:

Quark Matter 2017: http://qm2017.phy.uic.edu/

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

ALICE: http://aliceinfo.cern.ch/Public/Welcome.html

ATLAS: http://atlas.cern/

CMS: http://cms.web.cern.ch/

LHCb: http://lhcb-public.web.cern.ch/lhcb-public/

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

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

Best regards, Orbiter.ch

Three Spaceships Targeting February and March Launches











ISS - Expedition 50 Mission patch.

February 10, 2017

Aurora above the International Space Station. Animation credits mentioned

The Expedition 50 crew is gearing up for three different spaceships in two months to resupply the International Space Station. The crew also worked today on a variety of research hardware and practiced an emergency drill.

Two U.S. companies are getting their rockets ready to deliver food, fuel, supplies and new science gear to the crew. SpaceX is first in line with a plan to launch their Dragon spacecraft atop its Falcon 9 rocket no earlier than Feb. 18. Next, Orbital ATK is targeting March 19 to launch their Cygnus spacecraft on its seventh resupply mission to the station. Both spaceships will be captured by the Canadarm2 robotic. The Dragon will be installed to the Harmony module and the Cygnus will be attached to the Unity module.


Image above: Stars, the aurora and the International Space Station’s solar arrays are seen in this picture taken Jan. 18, 2017. Image Credit: NASA.

Russia is preparing its Progress 66 (66P) cargo craft for a Feb. 22 launch from Kazakhstan. The 66P will take a two-day trip to the orbital laboratory before automatically docking to the Pirs Docking Compartment.

Onboard the station, Flight Engineer Thomas Pesquet spent the day in Japan’s Kibo lab module working on science gear maintenance. NASA astronaut Peggy Whitson installed a leak locator in Kibo’s airlock that will be used to locate the source of an ammonia leak outside the Japanese lab.

Commander Shane Kimbrough and his Soyuz crewmates cosmonauts Andrey Borisenko and Sergey Ryzhikov got together in the afternoon an emergency descent drill. The trio practiced the procedures necessary to evacuate the station quickly in the unlikely event of an emergency and return to Earth inside their Soyuz MS-02 spacecraft.

Related links:

Orbital ATK: https://blogs.nasa.gov/spacestation/tag/orbital-atk/

Progress: https://blogs.nasa.gov/spacestation/tag/progress/

Roscosmos: https://blogs.nasa.gov/spacestation/tag/roscosmos/

SpaceX: https://blogs.nasa.gov/spacestation/tag/spacex/

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

Imag (mentioned), Animation (mentioned), Text, Credits: NASA/Mark Garcia.

Best regards, Orbiter.ch

New Data from NOAA GOES-16’s Space Environment In-Situ Suite (SEISS) Instrument












NOAA & NASA - GEOS logo.

Feb. 10, 2017

The new Space Environment In‐Situ Suite (SEISS) instrument onboard NOAA’s GOES-16 is working and successfully sending data back to Earth.

A plot from SEISS data showed how fluxes of charged particles increased over a few minutes around the satellite on January 19, 2017. These particles are often associated with brilliant displays of aurora borealis at northern latitudes and australis at southern latitudes; however, they can pose a radiation hazard to astronauts and other satellites, and threaten radio communications.


Graphics above: This plot of SEISS data shows injections of protons and electrons observed by the Magnetospheric Particle Sensors MPS-HI and Solar and Galactic Proton Sensor (SGPS) on January 19, 2017. MPS-HI and SGPS are two of the individual sensor units on SEISS. The fluxes shown are from the MPS-HI telescopes that look radially outward from the Earth, and from the lowest-energy channel observed by the eastward-looking SGPS. Graphics Credits: NOAA/NASA.

Information from SEISS will help NOAA's Space Weather Prediction Center  provide early warning of these high flux events, so astronauts, satellite operators and others can take action to protect lives and equipment.

SEISS is composed of five energetic particle sensor units. The SEISS sensors have been collecting data continuously since January 8, 2017, with an amplitude, energy and time resolution that is greater than earlier generations of NOAA’s geostationary satellites. 

SEISS was built by Assurance Technology Corporation and its subcontractor, the University of New Hampshire.

NOAA’s GOES-16 satellite. Image Credits: NASA/NOAA

NASA successfully launched GOES-R at 6:42 p.m. EST on November 19, 2016 from Cape Canaveral Air Force Station in Florida and it was renamed GOES-16 when it achieved orbit. GOES-16 is now observing the planet from an equatorial view approximately 22,300 miles above the surface of the Earth.

NOAA’s satellites are the backbone of its life-saving weather forecasts. GOES-16 will build upon and extend the more than 40-year legacy of satellite observations from NOAA that the American public has come to rely upon.

For more information about GOES-16, visit: http://www.goes-r.gov/ or http://www.nasa.gov/goes

To learn more about the GOES-16 SEISS instrument, visit:

http://www.goes-r.gov/spacesegment/seiss.html

Image (mentioned), Graphics (mentioned), Text, Credits: NASA's Goddard Space Flight Center/Rob Gutro/Lynn Jenner.

Greetings, Orbiter.ch

Asteroid Resembles Dungeons and Dragons Dice










Asteroid Watch logo.

Feb. 10, 2017


Image above: This composite of 25 images of asteroid 2017 BQ6 was generated with radar data collected using NASA’s Goldstone Solar System Radar in California's Mojave Desert. The images were gathered on Feb. 7, 2017, between 8:39 and 9:50 p.m. PST (11:39 p.m. EST and 12:50 a.m., Feb. 7), revealing an irregular, angular-appearing asteroid about 660 feet (200 meters) in size that rotates about once every three hours. The images have resolutions as fine as 12 feet (3.75 meters) per pixel. Image Credits: NASA/JPL-Caltech/GSSR.

Radar images of asteroid 2017 BQ6 were obtained on Feb. 6 and 7 with NASA’s 70-meter (230-foot) antenna at the Goldstone Deep Space Communications Complex in California. They reveal an irregular, angular-appearing asteroid about 660 feet (200 meters) in size that rotates about once every three hours. The images have resolutions as fine as 12 feet (3.75 meters) per pixel.

“The radar images show relatively sharp corners, flat regions, concavities, and small bright spots that may be boulders,” said Lance Benner of NASA’s Jet Propulsion Laboratory in Pasadena, California, who leads the agency’s asteroid radar research program. “Asteroid 2017 BQ6 reminds me of the dice used when playing Dungeons and Dragons. It is certainly more angular than most near-Earth asteroids imaged by radar.”

Asteroid 2017 BQ6 safely passed Earth on Feb. 6 at 10:36 p.m. PST (1:36 a.m. EST, Feb. 7) at about 6.6 times the distance between Earth and the moon (about 1.6 million miles, or 2.5 million kilometers). It was discovered on Jan. 26 by the NASA-funded Lincoln Near Earth Asteroid Research (LINEAR) Project, operated by MIT Lincoln Laboratory on the Air Force Space Command’s Space Surveillance Telescope at White Sands Missile Range, New Mexico.


Image above: This composite of 11 images of asteroid 2017 BQ6 was generated with radar data collected using NASA’s Goldstone Solar System Radar in California's Mojave Desert on Feb. 5, 2017, between 5:24 and 5:52 p.m. PST (8:24 to 8:52 p.m. EST / 1:24 to 1:52 UTC). The images have resolutions as fine as 12 feet (3.75 meters) per pixel. Image Credits: NASA/JPL-Caltech/GSSR.

Radar has been used to observe hundreds of asteroids. When these small, natural remnants of the formation of the solar system pass relatively close to Earth, deep space radar is a powerful technique for studying their sizes, shapes, rotation, surface features, and roughness, and for more precise determination of their orbital path.

NASA's Jet Propulsion Laboratory, Pasadena, California, manages and operates NASA’s Deep Space Network, including the Goldstone Solar System Radar, and hosts the Center for Near-Earth Object Studies for NASA's Near-Earth Object Observations Program within the agency's Science Mission Directorate.

JPL hosts the Center for Near-Earth Object Studies for NASA's Near-Earth Object Observations Program within the agency's Science Mission Directorate.

More information about asteroids and near-Earth objects can be found at:

http://cneos.jpl.nasa.gov

http://www.jpl.nasa.gov/asteroidwatch

For more information about NASA's Planetary Defense Coordination Office, visit:

http://www.nasa.gov/planetarydefense

For asteroid and comet news and updates, follow AsteroidWatch on Twitter:

http://twitter.com/AsteroidWatch

Asteroids: https://www.nasa.gov/mission_pages/asteroids/main/index.html

Images (mentioned), Text, Credits: NASA/Tony Greicius/JPL/DC Agle.

Greetings, Orbiter.ch

Hubble Sees Spiral in Andromeda











NASA - Hubble Space Telescope patch.

Feb. 10, 2017


The Andromeda constellation is one of the 88 modern constellations and should not be confused with our neighboring Andromeda Galaxy. The Andromeda constellation is home to the pictured galaxy known as NGC 7640.

Many different classifications are used to identify galaxies by shape and structure — NGC 7640 is a barred spiral type. These are recognizable by their spiral arms, which fan out not from a circular core, but from an elongated bar cutting through the galaxy’s center. Our home galaxy, the Milky Way, is also a barred spiral galaxy. NGC 7640 might not look much like a spiral in this image, but this is due to the orientation of the galaxy with respect to Earth — or to Hubble, which acted as photographer in this case! We often do not see galaxies face on, which can make features such as spiral arms less obvious.

There is evidence that NGC 7640 has experienced some kind of interaction in its past. Galaxies contain vast amounts of mass, and therefore affect one another via gravity. Sometimes these interactions can be mild, and sometimes hugely dramatic, with two or more colliding and merging into a new, bigger galaxy. Understanding the history of a galaxy, and what interactions it has experienced, helps astronomers to improve their understanding of how galaxies — and the stars within them — form.

For images and more information about Hubble, visit:

http://hubblesite.org/
http://www.nasa.gov/hubble
http://www.spacetelescope.org/

Image, Text, Credits: ESA/Hubble & NASA/Text Credits: European Space Agency/NASA/Karl Hille.

Best regards, Orbiter.ch

New Horizons Exits Brief Safe Mode, Recovery Operations Continue












NASA - New Horizons Mission logo.

Feb. 10, 2017

NASA’s New Horizons spacecraft is operating normally after just over 24 hours in a protective “safe mode,” the result of a command-loading error that occurred early Thursday. The spacecraft is designed to automatically transition to safe mode under certain anomalous conditions to protect itself from harm. In safe mode, the spacecraft suspends its timeline of activities and keeps its antenna pointed toward Earth to listen for instructions from the Mission Operations Center at the Johns Hopkins University Applied Physics Laboratory (APL) in Laurel, Maryland.


Image above: Artist's impression of NASA's New Horizons spacecraft, en route to a January 2019 encounter with Kuiper Belt object 2014 MU69. Image Credits: NASA/JHUAPL/SwRI.

“Our rapid recovery was supported by other NASA missions that provided New Horizons with some of their valuable Deep Space Network [DSN] antenna time,” said Alice Bowman, New Horizons mission operations manager at APL. “This is the norm for missions using the DSN – we support one another when challenges arise.” 

New Horizons is healthy and continues to speed along toward its next target – the Kuiper Belt object 2014 MU69 – while its operations team works to restore it to full operations and resume scientific data collection. Due to the 10.5-hour round trip communications delay that results from operating a spacecraft more than 3.5 billion miles (5.7 billion kilometers) from Earth, the team expects New Horizons to be back on its activities timeline early Sunday, Feb. 12.

Related link:

SCaN (Space Communications and Navigation): https://www.nasa.gov/directorates/heo/scan/index.html

For more information about New Horizons, visit: http://www.nasa.gov/mission_pages/newhorizons/main/index.html

Image (mentioned), Text, Credits: NASA/Tricia Talbert.

Greetings, Orbiter.ch

Comet’s Trip Past Earth Offers First in a Trio of Opportunities












NASA patch.

Feb. 10, 2017

Comet hunters still have a chance to see comet 45P/Honda-Mrkos-Pajdušáková in the next few days using binoculars or a telescope. It’s the first of a trio of comets that will -- between now and the end of 2018 -- pass close enough to Earth for backyard observers to try to spot and for scientists to study using ground-based instruments.

Comet 45P will come closest to Earth on the morning of Saturday, Feb. 11, when it passes by at a distance of about 7.7 million miles (12.4 million kilometers), or more than roughly 30 times the distance between Earth and the moon. It is currently in the early morning eastern sky, though the full moon may make the comet more difficult to spot. The recommendation for backyard astronomers is to use binoculars or a telescope to look for the comet several times during the coming days.


Image above: Comet 45P/Honda-Mrkos-Pajdušáková is captured using a telescope on December 22 from Farm Tivoli in Namibia, Africa. Image Credit: Gerald Rhemann.

Discovered in 1948, 45P is a short-period comet, with an orbit that takes it around the sun and out by Jupiter about every 5-1/4 years. This weekend’s encounter will be the comet’s closest with Earth through the end of this century. The comet will pass by our planet again in 2032 but will be much farther away – at a distance of nearly 30 million miles (about 48 million kilometers).

Scientists have taken advantage of 45P’s approach, making observations using powerful ground-based telescopes such as NASA’s Infrared Telescope Facility to investigate the gases, dust and ice particles that are released from the comet nucleus and show up in the coma and tail. By looking for water, methane and other important compounds, astronomers get clues about how the comet is put together and where it originated in the cloud of material that surrounded the young sun as the solar system formed.

By observing the same comet more than once, astronomers can see how the object changes over time.

“Observing a comet multiple times over successive orbits is like taking snapshots at different stages of life,” said Joseph Nuth, a senior scientist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “And some comets have harder lives than others, depending on how close they get to the sun. We can learn about these effects by comparing different comets with varying perihelion distances over time.”

Ground-based observations also are planned for comet 41P/Tuttle-Giacobini-Kresak, which will pass closest to Earth on April 1, 2017, and for comet 46P/Wirtanen, passing closest to Earth on Dec. 16, 2018. By studying this trio of comets, astronomers can learn more about the differences among comets – information they use to fill in the comet family tree.

“Comet 46P in particular will remain within 10 million miles of Earth for several weeks, from December 4 through 28, 2018,” said Goddard researcher Michael DiSanti. “This will permit detailed studies of its material, as successive regions of the comet’s nucleus become exposed to sunlight.”

View 45P on Gerald Rhemann's page: http://www.astrostudio.at/2_Bright%20Comets.php?img=images/2_Bright%20Comets/361_45P_22_12C.jpg

Comet 45P was featured recently in Astronomy Photo of the Day: https://apod.nasa.gov/apod/ap170102.html

Another reason to check out the skies tonight and early Saturday is the full moon with a penumbral eclipse. For more information, see http://nasa.tumblr.com/post/157061320334/subtle-lunar-eclipse

Comets: http://www.nasa.gov/comets

Image (mentioned), Text, Credits: NASA’s Goddard Space Flight Center, by Elizabeth Zubritsky/Karl Hille.

Greetings, Orbiter.ch

Nine Kilometer Impact Crater & Unlocking an Impact Crater's Clues












NASA - Mars Reconnaissance Orbiter (MRO) patch.

Feb. 10, 2017

 Nine Kilometer Impact Crater

This image reveals an impact crater, nine kilometers in diameter, with a central peak. Impact craters of various sizes and ages can be found across the Martian surface. Each impact crater on Mars possesses a unique origin and composition, which makes the HiRISE team very interested in sampling as many of them as possible!

Like the impact of a droplet into fluid, once an impact has occurred on the surface of Mars, an ejecta curtain forms immediately after, contributing to the raised rim visible at the top of the crater's walls. After the formation of the initial crater, if it is large enough, then a central peak appears as the surface rebounds. These central peaks can expose rocks that were previously deeply buried beneath the Martian surface.

The blue and red colors in this enhanced-contrast image reflect the effects of post-impact sedimentation and weathering over time.

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.

Impact Crater & Unlocking an Impact Crater's Clues

Mars is a dynamic planet. HiRISE has witnessed many surface changes over the past ten years, including hundreds of new craters formed by ongoing impacts. Most of these impacts are likely caused by asteroids that have strayed into collision courses with Mars. The planet's much thinner atmosphere compared to Earth makes small asteroids less likely to burn up prior to hitting the Martian surface.

This new crater, which formed explosively at the point of impact, has a diameter of roughly 8 meters (about 25 feet), but its surrounding blast zone and ejecta extend over a kilometer (about one mile) beyond the crater itself. The materials exposed nearest the crater have distinctive yellowish and lighter grey appearances, while more distant ejected materials range from dark brown to bright bluish in an enhanced-color view. These varied materials may have originated from different layers penetrated by the impact.

This new impact was discovered using the lower-resolution Context Camera (CTX), also on board Mars Reconnaissance Orbiter. An older CTX image of this region from May 2012 shows a uniformly dust-covered surface, while a newer CTX image from September 2016 reveals the crater's dark blast zone. New craters on Mars are easiest to locate in such dust-coated terrains, where they provide opportunistic "road cuts" that allow scientists to see beneath the dust blanket and determine the underlying rock compositions and textures.

Artist's view of Mars Reconnaissance Orbiter (MRO). Image Credits: NASA/JPL-Caltech

This particular crater formed about 300 kilometers (roughly 200 miles) east of the Spirit rover's final resting spot in Gusev Crater.

Original image scale range: 26.2 cm/pixel (with 1 x 1 binning) so objects ~79 cm across are resolved. Map projected scale: 25 cm/pixel and 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

Images (mentioned), Text, Credits: NASA/JPL-Caltech/Univ. of Arizona/Tony Greicius.

Greetings, Orbiter.ch

A Valentine: From Cassini with Love










NASA - Cassini International logo.

February 10, 2017

Saturn mission invites public to share artistic creations with #CassiniInspires.


Image above: Saturn Mosaic by Ian Regan. Image credits: NASA/JPL-Caltech/SSI/Ian Regan.

Although the motivation behind NASA's Cassini mission to Saturn was scientific, part of the planet's allure has long been in its undeniable physical beauty.


Animation above: Ring Motion by Sergio Maria-Fagundez. Animation credits: NASA/JPL-Caltech/SSI/Sergio Maria-Fagundez.

Since Cassini arrived at Saturn in 2004, dramatic views from the spacecraft's imaging cameras -- and other sensors that observe in infrared, ultraviolet and radio frequencies -- have revealed the ringed planet and its moons in unprecedented detail for scientists to study.

video
Cassini Inspires

Images taken by Cassini's cameras are published directly to the web shortly after they're received from the spacecraft, making them available for anyone to peruse and enjoy. And thus, throughout the journey, a dedicated community of space exploration enthusiasts has ridden along, sharing and discussing Cassini's images, often processing them to create their own spectacular scenes.


Image above: Saturn's Polar Storm by Roseann Arabia. Image credits: NASA/JPL-Caltech/Space Science Institute/Roseann Arabia.

"We're so gratified that Cassini's images have inspired people to work with the pictures themselves to produce such beautiful creations," said Linda Spilker, Cassini project scientist at NASA's Jet Propulsion Laboratory, Pasadena, California. "It's been truly wonderful for us to feel the love for Cassini from the public. The feeling from those of us on the mission is mutual.

Cassini Inspires

To celebrate the many ways Cassini's exploration of Saturn has sparked curiosity and wonder, the mission is launching a campaign planned to continue through the mission's dramatic conclusion in September.


Image above: Enceladus in the E Ring by Val Klavans. Image credits: NASA/JPL-Caltech/SSI/Val Klavans.

The activity, called "Cassini Inspires" invites members of the public to share their original Saturn-inspired artistic creations in a variety of different media (including painting, music, poetry, fiction, video or any format that can be shared online). To participate, artists post their creations on the social media platform of their choice, and tag them #CassiniInspires. For more information, visit:

https://saturn.jpl.nasa.gov/cassiniinspires

Launched in 1997, Cassini has been touring the Saturn system since arriving in 2004 for an up-close study of the planet, its rings and moons, and its vast magnetosphere. Cassini has made numerous dramatic discoveries, including a global ocean with indications of hydrothermal activity within the moon Enceladus, and liquid methane seas on another moon, Titan.


Image above: Half-phase Dione in Approximate True Color by Emily Lakdawalla. Image credits: NASA/JPL-Caltech/SSI/Emily Lakdawalla.

The mission is in its penultimate phase, performing weekly ring-grazing dives just past the outer edge of Saturn's main rings. In April, the spacecraft will begin its Grand Finale, plunging through the gap between the rings and the planet itself, leading up to a fateful plunge into Saturn on September 15.


Image above: Crescent Titan by Jason Major. Image credits: NASA/JPL-Caltech/SSI/Jason Major.

The Cassini-Huygens mission is a cooperative project of NASA, ESA (European Space Agency) and the Italian Space Agency. NASA's Jet Propulsion Laboratory, a division of Caltech in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington. JPL designed, developed and assembled the Cassini orbiter.

More information about Cassini:

http://www.nasa.gov/cassini

http://saturn.jpl.nasa.gov

http://www.esa.int/Our_Activities/Space_Science/Cassini-Huygens

Images (mentioned), Animation (mentioned), Video, Text, Credits: NASA/JPL/Preston Dyches.

Best regards, Orbiter.ch

jeudi 9 février 2017

Probe May Improve Weather Forecasts












NASA Armstrong Flight Research Center Ikhana MQ-9 patch.

Feb. 9, 2017

A weather probe that eventually will relay atmospheric conditions as they are unfolding and provide data to improve weather forecasts and models, has begun to fly on NASA’s Ikhana remotely piloted aircraft.

The flights mark the first time that the Panasonic Tropospheric Airborne Meteorological Data Reporting, or TAMDAR, Edge probe system has flown on an unmanned aircraft system as large as the Ikhana, said Ed Diks, Ikhana deputy project manager. The Ikhana flights are based at NASA Armstrong Flight Research Center in California.

“The weather information can benefit any kind of commercial or military aircraft and it could have uses for unmanned aircraft systems in the future,” Diks said.


Image above: The Ikhana aircraft is flying a TAMDAR Edge probe that could significantly improve weather models and forecasts. Image Credits: NASA Photo/Lori Losey.

The TAMDAR Edge system is a miniaturized, lightweight version of the TAMDAR Edge probe that has been flying on commercial airliners for more than 12 years. Panasonic Weather Solutions and Armstrong have partnered under the Space Act Agreement to develop the technology to greatly enhance flight safety involving weather, Diks said.

Ikhana pilot Hernan Posada sees the value in good weather forecasts.

“Weather is vital to our safe operation of this aircraft,” Posada said. “We adhere to strict airspace rules and manufacturer limits and seeing weather and being able to avoid it is a plus.”

The full capability of the probe will begin later this year when TAMDAR and the Iridium communications satellite network will provide real-time weather to pilots and used to validate and improve weather forecasting models, Diks said. The TAMDAR Edge probe measures and detects real-time weather data including winds aloft, temperature, humidity, GPS position and altitude, pressure, altitude, airspeed, icing presence and turbulence, he added.

“We will verify that we can transmit data and that the recipients of the data can read it,” he explained. “At the moment we have to land, download the data and then complete the analysis. The best operational use for the developers of the system would be to access that information whenever they want it and help develop weather models to make better predictions,” Diks explained.

The benefit to aviation increases in remote areas without major airports that NASA Armstrong missions take place, where there is little or no local weather data, said Scott Wiley, a NASA Armstrong meteorologist.

“We have a lot of data at LAX (Los Angeles International Airport),” he explained. “We have a lot of data in Seattle. We have a lot of data in Chicago. However, we don’t have a lot of data in remote areas. We don’t have any data in the polar regions in places where the DC-8 flies or over hurricanes where the Global Hawk makes observations. We are filling the data gaps with TAMDAR to improve the weather models and forecasts. It’s a tremendous benefit to have this data.”

The TAMDAR Edge probe provides a way to provide weather data that is not available through traditional weather collection tools.

“Meteorologists use the weather data from a number of sources to gather temperature, pressure, wind speed and direction,” Wiley explained. “That data, surface data and radiosonde (sensor packages that usually travel through the atmosphere on weather balloons to gather weather details) data are incorporated into the weather model to come up with a forecast. We are not just forecasting for the surface, but also aloft. Other than the radiosondes that go up twice a day, we really don’t get a lot of airborne data.”

TAMDAR data includes vital moisture readings, Wiley said.


Image above: The TAMDAR Edge probe seen in the middle of the NASA Armstrong Ikhana is flying on a large remotely piloted aircraft for the first time. Image Credits: NASA Photo/Ken Ulbrich.

“Moisture is to the atmosphere as gasoline is to a fire,” Wiley explained. “We need the moisture data. An unstable atmosphere will result in a thunderstorm if we have met the threshold level of moisture, but if we don’t we don’t have a storm. You don’t have to guess with TAMDAR data Conventional weather data from modern aircraft do not often report moisture.”

It also could have a role in NASA’s Unmanned Aircraft Systems in the National Airspace System, or UAS in the NAS. Weather observation is the primary use now and although the probe will be collecting data during upcoming UAS in the NAS missions, it will not directly contribute to that effort or have connectivity with the Iridium satellite network, Diks said.

Another improvement to the TAMDAR Edge probe for NASA research is a heated probe, Wiley said. If a pilot encounters icing, the TAMDAR probe could be a backup detector. In fact, NASA Armstrong and NASA Glenn Research Center in Cleveland are considering working together to test the probe in Glenn’s icing wind tunnel to determine quantitative icing characteristics of trace icing, moderate icing or severe icing using the probe.

The TAMDAR Edge probe also can tie into another NASA Armstrong research project, the Weather Hazard Alert and Awareness Technology Radiation Radiosonde, or WHAATRR Glider, Wiley said. WHAATRR gliders are envisioned as reusable radiosondes that could provide real-time weather data to mission managers and pilots.

“We want to develop a dropsonde capable WHAATRR glider that would be dropped into weather hazards from the TAMDAR Edge equipped DC-8 and Global Hawk,” Wiley said. “The WHAATRR Gliders would fly in areas too dangerous for aircraft, while the Global Hawk and DC-8 motherships would fly all-around and especially upstream of the hazards and providing valuable data used to forecast changes in intensity, motion and size. Current costs of evacuating a coastline for hurricane warning costs $1 million a mile. Forecasting the exact hurricane landfall would save a lot of money for cities, states and emergency services.”

Armstrong Flight Research Center: https://www.nasa.gov/centers/armstrong/home/index.html

Aeronautics: https://www.nasa.gov/topics/aeronautics/index.html

Images (mentioned), Text, Credits: NASA Armstrong Flight Research Center/Jay Levine, X-Press editor/Monroe Conner.

Greetings, Orbiter.ch

NASA Spacecraft Prepares to Fly to New Heights












NASA - MMS Mission patch.

Feb. 9, 2017

On Feb. 9, 2017, NASA’s Magnetospheric Multiscale mission, known as MMS, began a three-month long journey into a new orbit. MMS flies in a highly elliptical orbit around Earth and the new orbit will take MMS twice as far out as it has previously flown. In the new orbit, which begins the second phase of its mission, MMS will continue to map out the fundamental characteristics of space around Earth, helping us understand this key region through which our satellites and astronauts travel. MMS will fly directly through regions – where giant explosions called magnetic reconnection occur – never before observed in high resolution.

Launched in March 2015, MMS uses four identical spacecraft to map magnetic reconnection – a process that occurs when magnetic fields collide and re-align explosively into new positions. NASA scientists and engineers fly MMS in an unprecedentedly close formation that allows the mission to travel through regions where the sun's magnetic fields interact with Earth's magnetic fields – but keeping four spacecraft in formation is far from easy.

“This is one of the most complicated missions Goddard has ever done in terms of flight dynamics and maneuvers,” said Mark Woodard, MMS mission director at NASA’s Goddard Flight Space Center in Greenbelt, Maryland. “No one anywhere has done formation flying like this before.”

video
MMS Phase 2b: Transitioning to Magnetosphere Science on the Darkside

Video above: Over three months, the MMS spacecraft transitions from the dayside magnetopause, to a new, larger orbit on the nightside, as shown in this visualization. Image Credits: NASA's Goddard Space Flight Center/Tom Bridgman, visualizer.

To form a three-dimensional picture of reconnection, the mission flies four individual satellites in a pyramid formation called a tetrahedron. While a previous joint ESA (European Space Agency)/NASA mission flew in a similar formation, MMS is the first to fly in such an extremely tight formation – only four miles apart on average. Maintaining this close separation allows for high-resolution mapping but adds an extra dimension of challenge to flying MMS, which is already a complex undertaking.

Flying a spacecraft, as one would suspect, is nothing like driving a car. Instead of focusing on just two dimensions – left and right, forward and backwards – you also must consider up and down. Add on to that, keeping the four MMS spacecraft in the specific tetrahedral formation necessary for three-dimensional mapping, and you’ve got quite a challenge. And don’t forget to avoid any space debris and other spacecraft that might cross your path. Oh, and each spacecraft is spinning like a top, adding another layer to the dizzying complexity.

“Typically, it takes about two weeks to go through the whole procedure of designing maneuvers,” said Trevor Williams, MMS flight dynamics lead at NASA Goddard.

Williams leads a team of about a dozen engineers to make sure MMS’s orbit stays on track. During a normal week of operations, the maneuvers, which have been carefully crafted and calculated beforehand, are finalized in a meeting at the start of the week.

To calculate its location, MMS uses GPS, just like a smart phone. The only difference is this GPS receiver is far above Earth, higher than the GPS satellites sending out the signals.

“We’re using GPS to do something it wasn’t designed for, but it works,” Woodard said.

Since GPS was designed with Earth-bound users in mind, signals are broadcast downwards, making it difficult to use from above. Fortunately, signals from GPS satellites are sent widely to blanket the entire planet and consequentially some from the far side of the planet sneak around Earth and continue up into space, where MMS can observe them. Using a special receiver that can pick up weak signals, MMS is able to stay in constant GPS contact. The spacecraft uses the GPS signals to automatically compute their location, which they send down to the flight control headquarters at Goddard. The engineers then use that positioning to design the maneuvers for the spacecraft’s orbits.

While the orbit for each MMS spacecraft is almost identical, small adjustments need to be made to keep the spacecraft in a tight formation. The engineers also rely on reports from NASA’s Conjunction Assessment Risk Analysis, which identifies the locations of space debris and provides notification when objects, like an old communications satellite, might cross MMS’s path. While nothing yet has been at risk for colliding with MMS, the crew has a prepared backup plan – a dodge maneuver – should the need arise.

On scheduled Wednesdays, one or two per month, the commands are sent up to the spacecraft to adjust the tetrahedral formation and make any necessary orbit adjustments. These commands tell MMS to fire its thrusters in short bursts, propelling the spacecraft to its intended location.

Moving MMS is a slow process. Each spacecraft is equipped with thrusters that provide four pounds of thrust, but they also weigh nearly a ton each. The spacecraft all spin like tops, so the timing of each burst needs to be precisely synchronized to push the spacecraft in the right direction.

The next day, once the spacecraft are in their proper locations, a second round of commands are given to fire the thrusters in the opposite direction, to fix the spacecraft in formation. Without this command, the spacecraft would overshoot their intended positions and drift apart with no resisting forces to stop them.  

Unlike airplanes, which constantly fire their engines to keep in motion, the spacecraft rely on their momentum to carry them around their orbit. Only short bursts from their thrusters, lasting just a few minutes, are required to maintain their formation and make minor adjustments to the orbit.

“We spend 99.9 percent of the time coasting because we need to be sparing with the fuel,” Williams said.

 The four MMS spacecrafts - Shown here in an artist's concept. Image Credit: NASA

Launched with 904 pounds of fuel, the spacecraft have only used about 140 pounds in their first two years of operation. However, sending MMS into a wider orbit for its second phase will consume about half the remaining fuel – and there are no gas stations in space for refueling. The operations crew carefully plan each maneuver to minimize fuel consumption. Typical maneuvers take less than half a pound of fuel and the crew hopes their fuel conservation efforts will save MMS enough fuel to allow extended studies past the end of the primary mission.  

The new elliptical orbit will take MMS to within 600 miles above the surface of Earth at its closest approach, and out to about 40 percent of the distance to the moon. Previously, the spacecraft went out only one-fifth (20 percent) of the distance to the moon.

In the first phase of the mission, MMS investigated the sun-side of Earth’s magnetosphere, where the sun's magnetic field lines connect to Earth's magnetic field lines, allowing material and energy from the sun to funnel into near-Earth space. In the second phase, MMS will pass through the night side, where reconnection is thought to trigger auroras.

In addition to helping us understand our own space environment, learning about the causes of magnetic reconnection sheds light on how this phenomenon occurs throughout the universe, from auroras on Earth, to flares on the surface of the sun, and even to areas surrounding black holes.

While MMS will not maintain its tetrahedral formation as it moves to its new orbit, it will continue taking data on the environments it flies through. The operations crew expects MMS to reach its new orbit on May 4, 2017, at which point it will be back in formation and ready to collect new 3-D science data, as its elliptical orbit carries it through specific areas thought to be sites for magnetic reconnection.

Learn more about the MMS mission and its science discoveries here: https://www.nasa.gov/mission_pages/mms/index.html

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

Greetings, Orbiter.ch

NASA's OSIRIS-REx Begins Earth-Trojan Asteroid Search











NASA - OSIRIS-REx Mission patch.

Feb. 9, 2017

A NASA spacecraft begins its search Thursday for an enigmatic class of near-Earth objects known as Earth-Trojan asteroids. OSIRIS-REx, currently on a two-year outbound journey to the asteroid Bennu, will spend almost two weeks searching for evidence of these small bodies.

Trojan asteroids are trapped in stable gravity wells, called Lagrange points, which precede or follow a planet. OSIRIS-REx is currently traveling through Earth's fourth Lagrange point, which is located 60 degrees ahead in Earth's orbit around the sun, about 90 million miles (150 million kilometers) from our planet. The mission team will use this opportunity to take multiple images of the area with the spacecraft’s MapCam camera in the hope of identifying Earth-Trojan asteroids in the region.

video
Searching for Earth’s Trojan Asteroids

Video above: Trojan asteroids are common at the L4 and L5 Lagrange points of other planets, leading or following the planet in its orbit. But detecting our own Trojan asteroids from Earth is difficult since they appear close to the sun from our perspective. Video Credits: NASA's Goddard Space Flight Center/Dan Gallagher, producer.

Although scientists have discovered thousands of Trojan asteroids accompanying other planets, only one Earth-Trojan has been identified to date, asteroid 2010 TK7. Scientists predict that there should be more Trojans sharing Earth’s orbit, but they are difficult to detect from Earth as they appear near the sun on the Earth’s horizon.

“Because the Earth’s fourth Lagrange point is relatively stable, it is possible that remnants of the material that built Earth are trapped within it,” said Dante Lauretta. “So this search gives us a unique opportunity to explore the primordial building blocks of Earth.”

The search commences today and continues through Feb. 20. On each observation day, the spacecraft’s MapCam camera will take 135 survey images that will be processed and examined by the mission’s imaging scientists at the University of Arizona, Tucson. The study plan also includes opportunities for MapCam to image Jupiter, several galaxies, and the main belt asteroids 55 Pandora, 47 Aglaja and 12 Victoria.

Artist's view of OSIRIS-REx spacecraft arrives at Bennu. Image Credit: NASA

Whether or not the team discovers any new asteroids, the search is a beneficial exercise. The operations involved in searching for Earth-Trojan asteroids closely resemble those required to search for natural satellites and other potential hazards around Bennu when the spacecraft approaches its target in 2018. Being able to practice these mission-critical operations in advance will help the OSIRIS-REx team reduce mission risk once the spacecraft arrives at Bennu.

NASA's Goddard Space Flight Center provides overall mission management, systems engineering and the safety and mission assurance for OSIRIS-REx. Dante Lauretta of the University of Arizona, Tucson, is the principal investigator, and the University of Arizona also leads the science team and the mission's observation planning and processing. Lockheed Martin Space Systems in Denver built the spacecraft and is providing flight operations. Goddard and KinetX Aerospace are responsible for navigating the OSIRIS-REx spacecraft. OSIRIS-REx is the third mission in NASA's New Frontiers Program. NASA's Marshall Space Flight Center in Huntsville, Alabama, manages the agency's New Frontiers Program for its Science Mission Directorate in Washington.

For more information on OSIRIS-Rex, visit: http://www.nasa.gov/osirisrex  and http://www.asteroidmission.org

Image (mentioned), Video (mentioned), Text, Credits: NASA’s Goddard Space Flight Center/Nancy Neal Jones/Karl Hille/University of Arizona/Erin Morton.

Greetings, Orbiter.ch

Hubble Witnesses Massive Comet-Like Object Pollute Atmosphere of a White Dwarf












NASA - Hubble Space Telescope patch.

Feb. 9, 2017

For the first time, scientists using NASA’s Hubble Space Telescope have witnessed a massive object with the makeup of a comet being ripped apart and scattered in the atmosphere of a white dwarf, the burned-out remains of a compact star. The object has a chemical composition similar to Halley’s Comet, but it is 100,000 times more massive and has a much higher amount of water. It is also rich in the elements essential for life, including nitrogen, carbon, oxygen, and sulfur.

These findings are evidence for a belt of comet-like bodies orbiting the white dwarf, similar to our solar system’s Kuiper Belt. These icy bodies apparently survived the star’s evolution as it became a bloated red giant and then collapsed to a small, dense white dwarf.


Image above: This artist's concept shows a massive, comet-like object falling toward a white dwarf. New Hubble Space Telescope findings are evidence for a belt of comet-like bodies orbiting the white dwarf, similar to our solar system's Kuiper Belt. The findings also suggest the presence of one or more unseen surviving planets around the white dwarf, which may have perturbed the belt to hurl icy objects into the burned-out star. Image Credits: NASA, ESA, and Z. Levy (STScI).

As many as 25 to 50 percent of white dwarfs are known to be polluted with infalling debris from rocky, asteroid-like objects, but this is the first time a body made of icy, comet-like material has been seen polluting a white dwarf’s atmosphere.

The results also suggest the presence of unseen, surviving planets which may have perturbed the belt and worked as a “bucket brigade” to draw the icy objects into the white dwarf. The burned-out star also has a companion star, which may disturb the belt, causing objects from the belt to travel toward the burned-out star.

Siyi Xu of the European Southern Observatory in Garching, Germany, led the team that made the discovery. According to Xu, this was the first time that nitrogen was detected in the planetary debris that falls onto a white dwarf. “Nitrogen is a very important element for life as we know it,” Xu explained. “This particular object is quite rich in nitrogen, more so than any object observed in our solar system.”

Our own Kuiper Belt, which extends outward from Neptune’s orbit, is home to many dwarf planets, comets, and other small bodies left over from the formation of the solar system. Comets from the Kuiper Belt may have been responsible for delivering water and the basic building blocks of life to Earth billions of years ago.

The new findings are observational evidence supporting the idea that icy bodies are also present in other planetary systems, and have survived throughout the history of the star’s evolution.

video
Hubble and the sunrise

To study the white dwarf’s atmosphere, the team used both Hubble and the W. M. Keck Observatory. The measurements of nitrogen, carbon, oxygen, silicon, sulfur, iron, nickel, and hydrogen all come from Hubble, while Keck provides the calcium, magnesium, and hydrogen. The ultraviolet vision of Hubble’s Cosmic Origins Spectrograph (COS) allowed the team to make measurements that are very difficult to do from the ground.

This is the first object found outside our solar system that is akin to Halley’s Comet in composition. The team used the famous comet for comparison because it has been so well studied.

The white dwarf is roughly 170 light-years from Earth in the constellation Bootes, the Herdsman. It was first recorded in 1974 and is part of a wide binary system, with a companion star separated by 2,000 times the distance that the Earth is from the sun.

The Hubble Space Telescope is a project of international cooperation between NASA and the European Space Agency. NASA Goddard manages the telescope. The Space Telescope Science Institute (STScI) in Baltimore, Maryland, conducts Hubble science operations. STScI is operated for NASA by the Association of Universities for Research in Astronomy in Washington, D.C.

For images and more information about Hubble, visit:

http://hubblesite.org/
http://www.nasa.gov/hubble
http://www.spacetelescope.org/

Image (mentioned), Video (ESA), Text, Credits: NASA/Karl Hille/STSI/Ann Jenkins/Ray Villard/ESO/Siyi Xu.

Best regards, Orbiter.ch

Dragon Training and Brain Imaging for Astronauts











ISS - Expedition 50 Mission patch.

February 9, 2017

The Expedition 50 crew trained yesterday for the robotic capture of the SpaceX Dragon and studied how the brain adapts to living in space. Three crew members also conducted an emergency drill aboard the International Space Station.

Flight Engineers Peggy Whitson and Thomas Pesquet joined Commander Shane Kimbrough to study the robotics maneuvers they will use when the SpaceX Dragon resupply ship arrives later this month. Dragon is targeted to liftoff mid-February atop a Falcon 9 rocket from Launch Pad 39A at Kennedy Space Center. The tenth commercial resupply mission from SpaceX will deliver advanced space research to improve disease-fighting drugs, observe Earth’s climate and automate spacecraft navigation.


Image above: Astronaut Thomas Pesquet, from the European Space Agency, works to load gear inside the Kibo laboratory module’s airlock. Image Credit: NASA.

Whitson also set up magnetic resonance brain imaging hardware for the NeuroMapping experiment. The study, which has been ongoing since 2014, is exploring changes in the brain and how an astronaut’s cognition, perception and motion are affected by long-term space missions.

Veteran station residents Oleg Novitskiy and Whitson along with first-time space flyer Pesquet practiced an emergency Soyuz descent today. The trio entered their Soyuz MS-03 spacecraft and simulated a scenario in the unlikely event the crew would have to evacuate the station quickly and return to Earth.

Related links:

Advanced space research to improve disease-fighting drugs: https://www.nasa.gov/mission_pages/station/research/experiments/1972.html

Observe Earth’s climate: https://www.nasa.gov/feature/sage-iii-to-look-back-at-earths-atmospheric-sunscreen

Automate spacecraft navigation: https://www.nasa.gov/mission_pages/station/research/experiments/1995.html

NeuroMapping experiment: https://www.nasa.gov/mission_pages/station/research/experiments/1007.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/Mark Garcia.

Best regards, Orbiter.ch

Jupiter From Below (Enhanced Color)












NASA - JUNO Mission logo.

Feb. 9, 2017


This enhanced-color image of Jupiter’s south pole and its swirling atmosphere was created by citizen scientist Roman Tkachenko using data from the JunoCam imager on NASA’s Juno spacecraft.

Juno acquired the image, looking directly at the Jovian south pole, on February 2, 2017, at 6:06 a.m. PST (9:06 a.m. EST) from an altitude of about 63,400 miles (102,100 kilometers) above Jupiter's cloud tops. Cyclones swirl around the south pole, and white oval storms can be seen near the limb -- the apparent edge of the planet.

JunoCam's raw images are available at http://www.missionjuno.swri.edu/junocam for the public to peruse and process into image products.

JPL manages the Juno mission for the principal investigator, Scott Bolton, of Southwest Research Institute in San Antonio. Juno is part of NASA's New Frontiers Program, which is managed at NASA's Marshall Space Flight Center in Huntsville, Alabama, for NASA's Science Mission Directorate. Lockheed Martin Space Systems, Denver, built the spacecraft. Caltech in Pasadena, California, manages JPL for NASA.

More information about Juno is online at http://www.nasa.gov/juno and http://missionjuno.swri.edu.

Image, Text, Credits: NASA/JPL-Caltech/SwRI/MSSS/Roman Tkachenko/Tony Greicius.

Greetings, Orbiter.ch

mercredi 8 février 2017

NASA Receives Science Report on Europa Lander Concept











NASA logo.

Feb. 8, 2017

A report on the potential science value of a lander on the surface of Jupiter’s icy moon Europa has been delivered to NASA, and the agency is now engaging the broader science community to open a discussion about its findings.   


Image above: This artist's rendering illustrates a conceptual design for a potential future mission to land a robotic probe on the surface of Jupiter's moon Europa. The lander is shown with a sampling arm extended, having previously excavated a small area on the surface. The circular dish on top is a dual-purpose high-gain antenna and camera mast, with stereo imaging cameras mounted on the back of the antenna. Three vertical shapes located around the top center of the lander are attachment points for cables that would lower the rover from a sky crane, which is envisioned as the landing system for this mission concept. Image Credits: NASA/JPL-Caltech.

In early 2016, in response to a congressional directive, NASA’s Planetary Science Division began a pre-Phase A study to assess the science value and engineering design of a future Europa lander mission. NASA routinely conducts such studies -- known as Science Definition Team (SDT) reports -- long before the beginning of any mission to gain an understanding of the challenges, feasibility and science value of the potential mission. In June 2016, NASA convened a 21-member team of scientists for the SDT. Since then, the team has deliberated to define a workable and worthy set of science objectives and measurements for the mission concept, submitting a report to NASA on Feb. 7.

The report lists three science goals for the mission. The primary goal is to search for evidence of life on Europa. The other goals are to assess the habitability of Europa by directly analyzing material from the surface, and to characterize the surface and subsurface to support future robotic exploration of Europa and its ocean. The report also describes some of the notional instruments that could be expected to perform measurements in support of these goals.

Europa Mission Spacecraft - Artist's Rendering

Image above: This artist's rendering shows NASA's Europa mission spacecraft, the mission would place a spacecraft in orbit around Jupiter in order to perform a detailed investigation of the giant planet's moon Europa -- a world that shows strong evidence for an ocean of liquid water beneath its icy crust and which could host conditions favorable for life. The highly capable, radiation-tolerant spacecraft would enter into a long, looping orbit around Jupiter to perform repeated close flybys of Europa. Image credit: NASA/JPL-Caltech.

Scientists agree that the evidence is quite strong that Europa, which is slightly smaller than Earth’s moon, has a global saltwater ocean beneath its icy crust. This ocean has at least twice as much water as Earth’s oceans. While recent discoveries have shown that many bodies in the solar system either have subsurface oceans now, or may have in the past, Europa is one of only two places where the ocean is understood to be in contact with a rocky seafloor (the other being Saturn's moon Enceladus). This rare circumstance makes Europa one of the highest priority targets in the search for present-day life beyond Earth.

The SDT was tasked with developing a life-detection strategy, a first for a NASA mission since the Mars Viking mission era more than four decades ago. The report makes recommendations on the number and type of science instruments that would be required to confirm if signs of life are present in samples collected from the icy moon's surface.

The team also worked closely with engineers to design a system capable of landing on a surface about which very little is known. Given that Europa has no atmosphere, the team developed a concept that could deliver its science payload to the icy surface without the benefit of technologies like a heat shield or parachutes.


Images above: This mosaic of images includes the most detailed view of the surface of Jupiter's moon Europa obtained by NASA's Galileo mission. The topmost footprint is the highest resolution image taken by Galileo at Europa. It was obtained at an original image scale of 19 feet (6 meters) per pixel. The other seven images in this observation were obtained at a resolution of 38 feet (12 meters) per pixel, thus the mosaic, including the top image, has been projected at the higher image scale. The top image is also provided at its original resolution, as a separate image file. It includes a vertical black line that resulted from missing data that was not transmitted by Galileo. This is the highest resolution view of Europa available until a future mission visits the icy moon. The right side of the image was previously published as PIA01180. Although this data has been publicly available in NASA's Planetary Data System archive for many years, NASA scientists have not previously combined these images into a mosaic for public release. This observation was taken with the sun relatively high in the sky, so most of the brightness variations visible here are due to color differences in the surface material rather than shadows. Bright ridge tops are paired with darker valleys, perhaps due to a process in which small temperature variations allow bright frost to accumulate in slightly colder, higher-elevation locations. Images Credits: NASA/JPL-Caltech.

The concept lander is separate from the solar-powered Europa multiple flyby mission, now in development for launch in the early 2020s. The spacecraft will arrive at Jupiter after a multi-year journey, orbiting the gas giant every two weeks for a series of 45 close flybys of Europa. The multiple flyby mission will investigate Europa’s habitability by mapping its composition, determining the characteristics of the ocean and ice shell, and increasing our understanding of its geology. The mission also will lay the foundation for a future landing by performing detailed reconnaissance using its powerful cameras.

NASA has announced two upcoming town hall meetings to discuss the Science Definition Team report and receive feedback from the science community. The first will be on March 19, in conjunction with the 2017 Lunar and Planetary Science Conference (LPSC) at The Woodlands, Texas. The second event will be on April 23 at the Astrobiology Science Conference (AbSciCon) in Mesa, Arizona.

To read the complete report visit: http://solarsystem.nasa.gov/europa/technical.cfm

Related links:

Mars Viking mission: http://mars.nasa.gov/programmissions/missions/past/viking/

Europa multiple flyby mission: https://www.nasa.gov/press-release/all-systems-go-for-nasas-mission-to-jupiter-moon-europa

2017 Lunar and Planetary Science Conference (LPSC): http://www.hou.usra.edu/meetings/lpsc2017/

Astrobiology Science Conference (AbSciCon): http://www.hou.usra.edu/meetings/abscicon2017/

Europa (Moon): https://www.nasa.gov/subject/3148/europa-moon

Europa Mission: http://www.nasa.gov/europa

Images (mentioned), Text, Credits: NASA/Tricia Talbert.

Greetings, Orbiter.ch

One Role of Mars Orbiter: Check Possible Landing Sites












NASA - Mars Reconnaissance Orbiter (MRO) logo.

Feb. 8, 2017


Animation above: NASA's Mars Reconnaissance Orbiter has been observing Mars since 2006, enabling it to document many types of changes, such as the way winds alter the appearance of this recent impact site. The orbiter's HiRISE camera took the four images used in this animated sequence in 2007, 2008, 2010 and 2012. Animation Credits: NASA/JPL-Caltech/Univ. of Arizona.

At an international workshop this week about where NASA's next Mars rover should land, most of the information comes from a prolific spacecraft that's been orbiting Mars since 2006.

Observations by NASA's Mars Reconnaissance Orbiter (MRO) provide the basis for evaluating eight candidate landing sites for the Mars 2020 rover mission. The landing site workshop this week in Monrovia, California, will narrow the Mars 2020 candidate list to four or fewer sites. MRO observations have been used to identify, characterize and certify past landing sites and are also in use to assess possible sites for future human-crew missions.

"From the point of view of evaluating potential landing sites, the Mars Reconnaissance Orbiter is the perfect spacecraft for getting all the information needed," said the workshop's co-chair, Matt Golombek of NASA's Jet Propulsion Laboratory, Pasadena, California. "You just can't overstate the importance of MRO for landing-site selection."

Engineers use MRO data to evaluate the safety of a candidate landing site. For example, stereoscopic 3-D information can reveal whether slopes are too steep, and some detailed images can show individual boulders big enough to be a landing hazard. Scientists use MRO data to evaluate how well a site could serve the research goals of a mission, such as the distribution of minerals that may have originated in wet environments.

"Missions on the surface of Mars give you the close-up view, but what you see depends on where you land. MRO searches the globe for the best sites," said MRO Deputy Project Scientist Leslie Tamppari of JPL.

Images, terrain models and mineral maps from the orbiter help the teams that operate NASA's two active Mars rovers plan driving routes. The Mars 2020 team has already used MRO data to evaluate driving options in the eight candidate sites for that rover, which is on track for launch in the summer of 2020 and landing in early 2021. The site evaluations even use MRO's capability to study the atmosphere above each site and probe underground features with ground-penetrating radar.

In the progress toward selecting a landing site for a future human mission to Mars, NASA is using MRO data to evaluate about 45 suggested sites that could support human exploration zones, which are areas that could support astronauts as they explore up to a 60-mile radius.

Still, the hundreds of MRO observations targeted specifically for study of potential landing sites make up a small fraction of all the data the mission has provided about Mars. MRO has acquired more than 224,000 images and millions of other observations during its nearly 50,000 orbits around Mars. This month, the mission will reach and pass a milestone of 300 terabits of total science data sent to Earth from the orbiter. That tops the combined total from all other interplanetary missions, past and present. It is more data than would be included in four months of nonstop high-definition video.

"Whether it is looking at the surface, the subsurface or the atmosphere of the planet, MRO has viewed Mars from orbit with unprecedented spatial resolution, and that produces huge volumes of data," said MRO Project Scientist Rich Zurek of JPL."These data are a treasure trove for the whole Mars scientific community to study as we seek to answer a broad range of questions about the evolving habitability, geology and climate of Mars."

Mars Reconnaissance Orbiter (MRO). Image Credits: NASA/JPL-Caltech

One of the orbiter’s six instruments has provided images of 99 percent of Mars -- equivalent to 97 percent of Earth’s land area -- in resolution sufficient to show features smaller than a tennis court. One-fifth of this coverage area has been imaged at least twice, providing stereo, 3-D information. Another instrument has returned several multi-spectral data sets for mapping surface composition, including one covering nearly 85 percent of Mars.The highest-resolution camera onboard has returned images revealing details as small as a desk in swaths covering a carefully chosen 2.8 percent of Mars’s surface. That's more than the areas of Texas, California, and all the states east of the Mississippi River combined.

Other instruments on MRO have provided daily weather maps of the entire planet since 2006, more than 20,000 radar-observing strips to examine subsurface layers of ice and rock, and more than 8.8 million atmospheric profiles of temperatures, clouds and dust.

New discoveries flow from the copious MRO data. Some are:

•  Minerals mapped by MRO indicate a diversity of ancient water-related environments, many apparently habitable.

•  There is enough carbon-dioxide ice buried in the south polar cap that, if released, it could more than double the planet’s present atmosphere.

•  Mars is a dynamic planet today, with dust storms, moving sand dunes, avalanches, new gullies and fresh impact craters.

•  Reservoirs of buried water ice that are remnants of past climates, including buried glaciers, have been confirmed and discovered.

•  Dark flows that appear in warm seasons on some slopes suggest brine activity, though they are still enigmatic and hold scant water at most.

•  Mars’ north polar cap is geologically young -- about five million years old -- and contains unequally spaced layers of dust and ice that are apparently related to cyclical changes in the planet’s tilt.

•  Large dust storms during southern spring and summer appear to have a pattern of three types, in sequence.

•  Seasonal surface changes at mid to high latitudes appear related to freezing and thawing of carbon dioxide.

In addition to MRO’s observations, whether for landing-site assessment or direct science investigations, the orbiter also provides communication relay service for robots on the Martian surface, whether mobile or stationary. This month, MRO will reach and pass a milestone of 6,000 relay sessions for Mars-surface missions.

Related link:

Eight candidate landing sites for the Mars 2020: http://mars.nasa.gov/mars2020/mission/timeline/prelaunch/landing-site-selection/

For additional information about MRO, visit: http://nasa.gov/mro and  Mars Reconnaissance Orbiter (MRO): http://www.nasa.gov/mission_pages/MRO/main/index.html

Animation (mentioned), Image (mentioned), Text, Credits: NASA/Laurie Cantillo/Dwayne Brown/Tony Greicius/JPL/Guy Webster.

Greetings, Orbiter.ch