vendredi 25 septembre 2015

Hubble Shears a "Woolly" Galaxy











NASA - Hubble Space Telescope patch.

Sept. 25, 201


This new image of the spiral galaxy NGC 3521 from the NASA/ESA Hubble Space Telescope is not out of focus. Instead, the galaxy itself has a soft, woolly appearance as it a member of a class of galaxies known as flocculent spirals.

Like other flocculent galaxies, NGC 3521 lacks the clearly defined, arcing structure to its spiral arms that shows up in galaxies such as Messier 101, which are called grand design spirals. In flocculent spirals, fluffy patches of stars and dust show up here and there throughout their disks. Sometimes the tufts of stars are arranged in a generally spiraling form, as with NGC 3521, but illuminated star-filled regions can also appear as short or discontinuous spiral arms.

About 30 percent of galaxies share NGC 3521's patchiness, while approximately 10 percent have their star-forming regions wound into grand design spirals.

NGC 3521 is located almost 40 million light-years away in the constellation of Leo (The Lion). The British astronomer William Herschel discovered the object in 1784. Through backyard telescopes, NGC 3521 can have a glowing, rounded appearance, giving rise to its nickname, the Bubble Galaxy.

video
Hubble and the sunrise over Earth

The Hubble Space Telescope is a project of international cooperation between NASA and the European Space Agency. NASA's Goddard Space Flight Center in Greenbelt, Maryland, 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.

For more information on the Hubble Space Telescope, visit:

http://www.nasa.gov/hubble

http://hubblesite.org/

http://www.spacetelescope.org/

Image Credits: ESA/Hubble & NASA and S. Smartt (Queen's University Belfast); Acknowledgement: Robert Gendler/Text, Video, Credit: European Space Agency (ESA).

Best regards, Orbiter.ch

Opportunity Mars Rover Preparing for Active Winter











NASA - Mars Exploration Rover B (MER-B) patch.

September 25, 2015

NASA's Mars Exploration Rover Opportunity is conducting a "walkabout" survey of "Marathon Valley," where the rover's operators plan to use the vehicle through the upcoming Martian winter, and beyond, to study the context for outcrops bearing clay minerals.

'Hinners Point' Above Floor of 'Marathon Valley' on Mars

Image above: This Martian scene shows contrasting textures and colors of "Hinners Point," at the northern edge of "Marathon Valley," and swirling reddish zones on the valley floor to the left. Image Credits: NASA/JPL-Caltech/Cornell Univ./Arizona State Univ.

Marathon Valley slices downhill from west to east for about 300 yards or meters through the western rim of Endeavour Crater. Opportunity has been investigating rock targets in the western portion of the valley since late July, working its way eastward in a thorough reconnaissance of the area.

The rover's panoramic camera has captured a scene dominated by a summit called "Hinners Point," forming part of the valley's northern edge. The image also shows a portion of the valley floor with swirling reddish zones that have been a target for study. It is online at:

http://www.jpl.nasa.gov/spaceimages/details.php?id=PIA19819

For several months starting in mid- to late October, the rover team plans to operate Opportunity on the southern side of the valley to take advantage of the sun-facing slope. The site is in Mars' southern hemisphere, so the sun is to the north during fall and winter days. Tilting the rover toward the sun increases power output from its solar panels. The shortest-daylight period of this seventh Martian winter for Opportunity will come in January 2016.

"Our expectation is that Opportunity will be able to remain mobile through the winter," said Mars Exploration Rover Project Manager John Callas of NASA's Jet Propulsion Laboratory, Pasadena, California.

The walkabout is identifying investigation targets in and near the valley floor. Rocks in reddish zones there contain more silica and less iron than most rocks in the area.

'Hinners Point' Above Floor of 'Marathon Valley' on Mars (Enhanced Color)

Image above: This Martian scene shows contrasting textures and colors of "Hinners Point," at the northern edge of "Marathon Valley," and swirling reddish zones on the valley floor to the left. Image Credits: NASA/JPL-Caltech/Cornell Univ./Arizona State Univ.

"We have detective work to do in Marathon Valley for many months ahead," said Opportunity Deputy Principal Investigator Ray Arvidson, of Washington University in St. Louis. "During the Martian late fall and winter seasons Opportunity will conduct its measurements and traverses on the southern side of the valley. When spring arrives the rover will return to the valley floor for detailed measurements of outcrops that may host the clay minerals."

Endeavour Crater spans about 14 miles (22 kilometers) in diameter. Opportunity has been studying its western rim since 2011. Marathon Valley became a high priority destination after a concentration of clay minerals called smectites was mapped there based on observations by the Compact Reconnaissance Imaging Spectrometer for Mars aboard NASA's Mars Reconnaissance Orbiter. Smectites form under wetter, milder conditions than most rocks at the Opportunity site. Opportunity is investigating relationships among clay-bearing and neighboring deposits for clues about the history of environmental changes.

'Hinners Point' Above Floor of 'Marathon Valley' on Mars (Stereo)

Image above: This stereo view from NASA's Mars Exploration Rover Opportunity shows contrasting textures and tones of "Hinners Point," at the northern edge of "Marathon Valley," and brighter outcrop on the valley floor to the left. Image Credits: NASA/JPL-Caltech/Cornell Univ./Arizona State Univ.

The rover team has been dealing for more than a year with Opportunity's tendency to undergo unplanned computer resets when using the type of onboard memory that retains information when power is off: flash memory. For three months until mid-September, operators fully avoided use of flash memory. In this mode, images and other data cannot be stored overnight, when the rover is powered off to conserve energy. To gain operational flexibility in a trade-off with possible "lost" days from resets, the team has resumed occasional use of flash memory.

Mars Exploration Rover. Image Credits: NASA/JPL Caltech

NASA's Mars Exploration Rover Project landed twin rovers Spirit and Opportunity on Mars in 2004 to begin missions planned to last three months. Both rovers far exceeded those plans. Spirit worked for six years, and Opportunity is still active. Findings about ancient wet environments on Mars have come from both rovers. The project is one element of NASA's ongoing and future Mars missions preparing for a human mission to the planet in the 2030s. JPL, a division of the California Institute of Technology, manages the project for NASA's Science Mission Directorate in Washington.

For more information about Opportunity, visit:

http://www.nasa.gov/rovers

http://marsrovers.jpl.nasa.gov

Follow the project on Twitter and Facebook at:

http://twitter.com/MarsRovers

http://www.facebook.com/mars.rovers

Images (mentioned), Text, Credits: NASA/JPL/Guy Webster.

Greetings, Orbiter.ch

Comet Report From Rosetta












ESA - Rosetta Mission patch.

Sept. 25, 2015

New images from Rosetta’s NAVCAM on 21 September 2015, about 330 km from the nucleus of Comet 67P/Churyumov-Gerasimenko.


Image above: Single frame enhanced NAVCAM image of Comet 67P/C-G taken on 21 September 2015. Image Credits: ESA/Rosetta/NAVCAM – CC BY-SA IGO 3.0.

The scale is 28.1 m/pixel and the image measures 28.8 km across. The contrast was increased to enhance the comet's activity; the original image is provided below.

The comet is oriented with the small lobe to the left and the large lobe to the right. Jets of gas and dust are seen all around the sunlit portion of the nucleus and are particularly clear around the central neck region with the ejected material seen extending towards the edge of the image frame.

This week Rosetta embarked on a new trajectory that will take it 1500 km away from the comet nucleus by 30 September in order to study the broader scale of the coma and to investigate the comet’s plasma environment. It will return to closer distances in mid-October.

Related links:

Rosetta Mission: http://www.esa.int/Our_Activities/Space_Science/Rosetta

Rosetta at Astrium: http://www.astrium.eads.net/en/programme/rosetta-1go.html

Rosetta at DLR: http://www.dlr.de/dlr/en/desktopdefault.aspx/tabid-10394/

Ground-based comet observation campaign: http://www.rosetta-campaign.net/home

ESA Rosetta blog: http://blogs.esa.int/rosetta/

Image (mentioned), Text, Credit: ESA.

Greetings, Orbiter.ch

Making (less of) an impact












ESA - Clean Space Programme logo.

25 September 2015

When a rocket is launched into space it crosses all layers of the atmosphere and interacts with them. How much impact does a launch have on the atmosphere and can we quantify the effect in such a way that we can take mitigation measures? These are only a few of the questions raised by the Clean Space AtILa (Atmospheric Impact of Launchers) project.

Neil Murray explains: "It is difficult to use computer modelling to precisely monitor what happens when a rocket is launched as the size of the plume is far smaller than the scale of the climate models that we use to model the atmosphere".

Picture perfect liftoff

Therefore two strategies were worked out to model the impact, one started from the size of the plume and this was allowed to develop over time and space to the size of the climate model and used as the boundary conditions of the climate model. Another strategy started from the size of the larger model and introduced sub-grid models which modelled the plume within the climate model grids.

Both models gave surprisingly similar results. So far it has been thought that chlorine, which is converted from the oxidizer (ammonia perchlorate) in the solid booster fuel mixture, has had the main effect on ozone depletion in the immediate area where the plume is emitted.

Computations conducted at ONERA using the CEDRE code

The latest studies have shown that alumina particles, i.e., oxidised aluminium, which is also present in the solid rocket fuel, may also have a significant ozone depletion effect depending on the particle size.

"If the particles are on the micrometer scale they would quickly fall out of the sky and have little impact on the atmosphere. However, the smaller the particles, the higher their combined surface area and the longer they remain suspended in the air, which means that their potential catalytic effect in ozone reduction could also be much higher."

Therefore it is imperative that quantitative data is collected to be able to accurately measure and predict the impact by mathematical models.

Computations conducted at ONERA using the CEDRE code

The first step towards quantitative data is the kick-off of an activity organised in cooperation with DLR whereby a solid rocket motor model in a wind tunnel will be used to simulate the evolution of particles in a representative rocket chamber and to then interpolate this to the conditions at launch. From these measurements accurate models will be developed for predicting the development of alumina particles under real launch conditions.

So why not just use real launch data? "It is not that easy to make these measurements during a real launch and so far no data has been collected for European launchers. Up to now we have mainly been relying on data measured by NASA during launches in the 1990s, however, the representativeness of this data with respect to European launchers is questionable. This ultimately leaves us with the task of somehow collecting such flight data and it is something that we are discussing at length." 

Ariane 5 ECA V184 climbout

"Even when we are able to make real-time measurements during a launch it still is a large task to interpret this data correctly and extrapolate this to all launches, as daily changes in the atmosphere and the time of the launch are just a few parameters that severely influence the effect. Luckily we are working with some of Europe’s experts in climatology!"

The AtILa project aims to understand the impact of launching its rockets into space by modelling the rocket plumes from their origin in the rocket chamber up to their impact on a global scale using climate models. This is one of the projects that ESA carries out under the Clean Space initiative which has carried out life cycle assessments for the space industry in order to monitor the effect of each space project on the environment. Implementing eco-design strategies into every phase of a space project is the ultimate aim of this initiative.

ESA links:

Life cycle assessment training at ESA: http://www.esa.int/Our_Activities/Space_Engineering_Technology/Clean_Space/Life_Cycle_Assessment_training_at_ESA

Virtual rocket launches will probe atmospheric effects: http://www.esa.int/Our_Activities/Space_Engineering_Technology/Clean_Space/Virtual_rocket_launches_will_probe_atmospheric_effects

Considering hydrazine-free satellite propulsion: http://www.esa.int/Our_Activities/Space_Engineering_Technology/Clean_Space/Considering_hydrazine-free_satellite_propulsion

'Green' satellite fuel designed to make space safer: http://www.esa.int/Our_Activities/Space_Engineering_Technology/Green_satellite_fuel_designed_to_make_space_safer

About Clean Space:

What is Clean Space?: http://www.esa.int/Our_Activities/Space_Engineering_Technology/Clean_Space/What_is_Clean_Space

Why is it needed?: http://www.esa.int/Our_Activities/Space_Engineering_Technology/Clean_Space/Why_is_it_needed

What are its objectives?: http://www.esa.int/Our_Activities/Space_Engineering_Technology/Clean_Space/What_are_its_objectives

Images, Text, Credits: ESA/CNES/ARIANESPACE/Photo Optique Vidéo CSG/Service POV du CSG.

Best regards, Orbiter.ch

Galileo satellites handed over to operator












ESA - Galileo Programme logo.

25 September 2015

Europe’s latest pair of Galileo satellites has passed its initial check out in space, allowing control to be handed over to the main control centre and join the growing fleet.

“This was a beautifully smooth start to the mission,” comments ESA mission director, Richard Lumb. 

“From liftoff through to handover to the constellation operator and beyond, this has been a textbook performance not only of the satellites but also for all the operations and manufacturer teams on the ground.”

Galileo satellite

Galileos 9 and 10 were launched on the morning of 11 September. Their individual lives began within four hours, as they separated from their rocket’s final stage, overseen from ESA’s ESOC operations centre in Darmstadt, Germany.

Days of round-the-clock effort followed, to bring the satellites to life, beginning with closely monitoring the unfolding of their solar wings and their pointing towards the Sun.

The various satellite elements were methodically switched on, their health checked and readied for work. 

Liviu Stefanov, an ESA flight director, described the process as “one of the smoothest yet.”

The satellites fired their thrusters to drift towards their target orbital positions at around 23 222 km altitude – helped along in this case by a near-perfect orbital injection to begin with.

Controlling Galileo

Firings will resume around the end of October to stop the drift and achieve fine positioning in orbit, guided by ESOC’s specialist flight dynamics team.

The accuracy of the Galileo system relies on the orbital position of its satellites being fixed to a very high level of precision.

Once on their way, the satellites were handed over on 19 and 20 September, respectively, to the Galileo Control Centre in Oberpfaffenhofen, Germany managed by SpaceOpal.

The team of engineers from ESA and France’s CNES space agency are preparing for the next launch, scheduled for December. The early phase for Galileos 11 and 12 will be overseen from CNES in Toulouse, France, which alternates with ESOC as hosts.

Galileo control centre

The navigation payloads on Galileos 9 and 10 still need to undergo detailed testing, led from ESA’s Redu centre in Belgium with the support of both Oberpfaffenhofen and the second Galileo Control Centre in Fucino, Italy, which has oversight of Galileo’s navigation mission.

This phase ensures the latest satellites’ navigation and search and rescue payloads are operating normally, giving them a clean bill of health before they can join the Galileo constellation.

Related links:

ESOC: http://www.esa.int/About_Us/ESOC

Galileo Control Centre Oberpfaffenhofen: http://www.dlr.de/gfr/en/desktopdefault.aspx/tabid-9565/16483_read-40351/

Images, Text, Credits: ESA/OHB/DLR.

Cheers, Orbiter.ch

jeudi 24 septembre 2015

Rokot launches with three Rodnik satellites







Eurockot Launch Services logo.

Sept. 24, 2015

Russian Rokot launch with three Rodnik satellites. Image Credit: Eurorockot

A Russian Rokot launch vehicle – with a Briz-KM Upper Stage – has successfully launched from the Plesetsk space center in northern Russia, carrying three Rodnik satellites along with potentially another – as yet unnamed – bird. The launch took place at 22:00 UTC on Wednesday.

video
Carrier rocket "Rokot" orbited three satellites for the Russian Defense Ministry

The Rokot’s latest mission was military by nature, as such little is known about the payloads. However, the Rodnik satellites are believed to be a version of the Gonets-M spacecraft.

Gonets-M or Rodnik satellite. Image Credit: Tsenki

The Gonets-M satellites – according to the Russian Space Agency – are intended to provide digital user terminal GLONASS positioning data, as well as electronic mail services. However, this is understood to be inaccurate, with Gonets-M having no role in the GLONASS operation.

The Gonets-M satellites are upgraded versions of the Gonets satellites, a derivative of the military Strela-3 satellite system. Rodnik satellites are believed to be the military version of the spacecraft family.

Artist's interpretation of the Rokot rocket launch. Image Credit: Eurorockot

Based on the Russian RS-18 (U.S. designation SS-19) Stiletto Intercontinental Ballistic Missile, the world first got a glimpse of the Rockot launch vehicle when it was launched from Baikonur in December of 1994. Designed to fill the gap between the workhorse Kosmos (1,500 kg to LEO) and Tsyklon (3,600 kg to LEO) vehicles, Rokot's payload capacity of 1,900 kg is perfect for launching two medium-sized satellites into Low Earth Orbit.

For more information about Eurorockot Launch Services, visit: http://www.eurockot.com/

Images, Video, Text, Credits: Eurorockot / tvzvezda.ru / Tsenki / Orbiter.ch Aerospace.

Greetings, Orbiter.ch

NASA Identifies Tropical Storm Dujuan's Strongest Side












NASA - ISS-RapidScat mission logo / NASA - Aqua EOS Mission logo.

Sept. 24, 2015

Tropical Storm Dujuan

 
Image above: The MODIS instrument aboard Aqua captured a visible image of Tropical Storm Dujuan at 04:40 UTC (12:40 a.m. EDT) on Sept 24. The MODIS image showed Dujuan has the signature comma shape of a tropical cyclone.
Image Credits: NASA Goddard MODIS Rapid Response Team.

The RapidScat instrument that flies aboard the International Space Station is an important tool for forecasters because it identifies where the strongest winds are located in a tropical cyclone when it is over open waters. RapidScat saw that Tropical Storm Dujuan's strongest side was in the southeastern quadrant.

On Sept. 23 at 4:11 p.m. EDT, RapidScat saw Tropical Storm Dujuan east of the Philippines and its strongest winds (red) were south and southeast of the center. Maximum sustained winds in both areas were as strong as 30 meters per second (67 mph/108 kph).


Image above: On Sept. 23 at 4:11 p.m. EDT, RapidScat saw Tropical Storm Dujuan east of the Philippines and its strongest winds (red) were southeast of the center. Image Credits: NASA JPL/Doug Tyler.

At 04:40 UTC (12:40 a.m. EDT) on Sept 24, the Moderate Resolution Imaging Spectroradiometer or MODIS instrument aboard Aqua captured a visible image of Tropical Storm Dujuan. The MODIS image showed Dujuan has the signature comma shape of a tropical cyclone.

Images from RapidScat are created at NASA's Jet Propulsion Laboratory in Pasadena, California, and MODIS images are created at NASA's Goddard Space Flight Center in Greenbelt, Maryland. 

ISS-RapidScat instrument in action. Animation Credit: NASA

At 11 a.m. EDT (1500 UTC), the center of Tropical Storm Dujuan was located near latitude 18.6 North, longitude 132.0 East. Dujuan is moving toward the west-southwest near 3 knots (3.4 mph/5.5 kph). Maximum sustained winds were near 55 knots (63.2 mph/ 101.9 kph) and Dujuan is expected to become a typhoon in the next couple of days peaking on September 27 with maximum sustained winds near 115 knots (132 mph/213 kph). Dujuan is moving to the north-northwest and is expected to track near Ishigakikima Island, Japan on September 27, and pass just north of Taiwan before making landfall in southeastern China on September 29.

For updated forecast tracks visit the Joint Typhoon Warning Center page: http://www.usno.navy.mil/JTWC/.

Related links:

ISS-RapidScat: http://www.nasa.gov/mission_pages/station/research/experiments/1067.html

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

Images (mentioned), Animation (mentioned), Text, Credits: NASA's Goddard Space Flight Center/Rob Gutro.

Greetings, Orbiter.ch

Antihydrogen at CERN: 20 years and going strong












CERN - European Organization for Nuclear Research logo.

Sept. 24, 2015

Twenty years ago a team of scientists at CERN led by Walter Oelert succeeded in producing the first atoms made of antimatter particles.

The nine atoms of antihydrogen – the antimatter counterpart of the simplest atom, hydrogen – were made at CERN’s Low Energy Antiproton Ring (LEAR) facility. This world premiere happened exactly 30 years after the discovery of the antiproton and opened a new chapter in the study of antimatter.

Low Energy Antiproton Ring (LEAR) facility. Image Credit: CERN

Comparisons of hydrogen and antihydrogen atoms constitute one of the best ways to make precise tests of differences between matter and antimatter. Their spectra are predicted to be identical, so any tiny differences would open a window to new physics, and could help in solving the antimatter mystery.

The atoms produced in 1995 remained in existence for about 40 billionths of a second, travelling for 10 metres at nearly the speed of light before being annihilated by ordinary matter and producing the signal that showed the anti-atoms had been formed.

Seven years later, CERN's Antiproton Decelerator (AD) made headlines around the world when the ATHENA and ATRAP experiments successfully produced large numbers of antihydrogen atoms for the first time.


Image above: The ALPHA experiment, one of five experiments that are studying antimatter at CERN (Image: Maximilien Brice/CERN).

Today, the AD serves five experiments that are studying antimatter in different ways: AEgIS, ALPHA, ASACUSA, ATRAP and BASE.

ALPHA – ATHENA’s successor – is specifically designed to trap antihydrogen particles for longer than its predecessors, so they can be studied in finer detail than ever before. The ALPHA collaboration has already measured the electric charge of an antiatom to a much higher precision than before. The ASACUSA collaboration, which also has high-precision studies of antihydrogen in its sights, has demonstrated the first-ever production of a beam of antiatoms.

Earlier this year further advances were made when the Baryon Antibaryon Symmetry Experiment (BASE) reported the most precise comparison of the charge-to-mass ratio of the proton to that of its antimatter equivalent, the antiproton. The study, which took 13,000 measurements over a 35-day period, showed that protons and antiprotons have identical mass-to-charge ratios.

The AEgIS experiment, which has just started operation this year, is designed specifically to measure the gravitational interaction of antimatter. Another, future experiment, GBAR, will make similar investigations.

These recent successes mark a growth in antimatter research that CERN’s AD can no longer keep up with, as more and more low-energy antiprotons are needed for experiments. An upgrade to the AD, called ELENA, will become operational in 2017. This is where GBAR will be installed.

ELENA will decelerate the antiprotons from the AD still further, allowing many more to be trapped by the experiments. With the additional ability to serve four experiments almost simultaneously, ELENA will usher in a new era in the investigation of the relationship between matter and antimatter in the universe.

For more read: "In the steps of the antiproton": http://cerncourier.com/cws/article/cern/62197

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:

CERN's Antiproton Decelerator (AD): http://home.web.cern.ch/about/accelerators/antiproton-decelerator

ATRAP experiment: http://home.web.cern.ch/about/experiments/atrap

ALPHA experiment: http://home.web.cern.ch/about/experiments/alpha

ELENA experiment: https://cds.cern.ch/journal/CERNBulletin/2011/30/News%20Articles/1368905

Related article:

BASE compares protons to antiprotons with high precision: http://orbiterchspacenews.blogspot.ch/2015/08/base-compares-protons-to-antiprotons.html

For more information about the European Organization for Nuclear Research (CERN), visit: http://home.web.cern.ch/

Images (mentioned), Text, Credits: CERN/Harriet Jarlett.

Best regards, Orbiter.ch

Perplexing Pluto: New ‘Snakeskin’ Image and More from New Horizons












NASA - New Horizons Mission logo.

Sept. 24, 2015

The newest high-resolution images of Pluto from NASA’s New Horizons are both dazzling and mystifying, revealing a multitude of previously unseen topographic and compositional details. The image below -- showing an area near the line that separates day from night -- captures a vast rippling landscape of strange, aligned linear ridges that has astonished New Horizons team members.

Artist's view of the New Horizons spacecraft passing over Pluto. Image Credit: NASA

“It’s a unique and perplexing landscape stretching over hundreds of miles,” said William McKinnon, New Horizons Geology, Geophysics and Imaging (GGI) team deputy lead from Washington University in St. Louis. “It looks more like tree bark or dragon scales than geology. This’ll really take time to figure out; maybe it’s some combination of internal tectonic forces and ice sublimation driven by Pluto’s faint sunlight.”

The “snakeskin” image of Pluto’s surface is just one tantalizing piece of data New Horizons sent back in recent days. The spacecraft also captured the highest-resolution color view yet of Pluto, as well as detailed spectral maps and other high-resolution images.


Image above: In this extended color image of Pluto taken by NASA’s New Horizons spacecraft, rounded and bizarrely textured mountains, informally named the Tartarus Dorsa, rise up along Pluto’s day-night terminator and show intricate but puzzling patterns of blue-gray ridges and reddish material in between. This view, roughly 330 miles (530 kilometers) across, combines blue, red and infrared images taken by the Ralph/Multispectral Visual Imaging Camera (MVIC) on July 14, 2015, and resolves details and colors on scales as small as 0.8 miles (1.3 kilometers). Image Credits: NASA/JHUAPL/SWRI.

The new “extended color” view of Pluto – taken by New Horizons’ wide-angle Ralph/Multispectral Visual Imaging Camera (MVIC) on July 14 and downlinked to Earth on Sept. 19 – shows the extraordinarily rich color palette of Pluto.

“We used MVIC’s infrared channel to extend our spectral view of Pluto,” said John Spencer, a GGI deputy lead from Southwest Research Institute (SwRI) in Boulder, Colorado. “Pluto’s surface colors were enhanced in this view to reveal subtle details in a rainbow of pale blues, yellows, oranges, and deep reds. Many landforms have their own distinct colors, telling a wonderfully complex geological and climatological story that we have only just begun to decode.”


Image above: This cylindrical projection map of Pluto, in enhanced, extended color, is the most detailed color map of Pluto ever made. It uses recently returned color imagery from the New Horizons Ralph camera, which is draped onto a base map of images from the NASA’s spacecraft’s Long Range Reconnaissance Imager (LORRI). The map can be zoomed in to reveal exquisite detail with high scientific value. Color variations have been enhanced to bring out subtle differences. Colors used in this map are the blue, red, and near-infrared filter channels of the Ralph instrument. Image Credits: NASA/JHUAPL/SWRI.

Additionally, a high-resolution swath across Pluto taken by New Horizons’ narrow-angle Long Range Reconnaissance Imager (LORRI) on July 14, and downlinked on Sept. 20, homes in on details of Pluto’s geology. These images -- the highest-resolution yet available of Pluto -- reveal features that resemble dunes, the older shoreline of a shrinking glacial ice lake, and fractured, angular water ice mountains with sheer cliffs. Color details have been added using MVIC’s global map shown above.

(Click on the image for enlarge)

Image above: High-resolution images of Pluto taken by NASA’s New Horizons spacecraft just before closest approach on July 14, 2015, reveal features as small as 270 yards (250 meters) across, from craters to faulted mountain blocks, to the textured surface of the vast basin informally called Sputnik Planum. Enhanced color has been added from the global color image. This image is about 330 miles (530 kilometers) across. For optimal viewing, zoom in on the image on a larger screen. Image Credits: NASA/JHUAPL/SWRI.

This closer look at the smooth, bright surface of the informally named Sputnik Planum shows that it is actually pockmarked by dense patterns of pits, low ridges and scalloped terrain. Dunes of bright volatile ice particles are a possible explanation, mission scientists say, but the ices of Sputnik may be especially susceptible to sublimation and formation of such corrugated ground.


Image above: High-resolution images of Pluto taken by NASA’s New Horizons spacecraft just before closest approach on July 14, 2015, are the sharpest images to date of Pluto’s varied terrain—revealing details down to scales of 270 meters. In this 75-mile (120-kilometer) section of the taken from the larger, high-resolution mosaic above, the textured surface of the plain surrounds two isolated ice mountains. Image Credits: NASA/JHUAPL/SWRI.

Beyond the new images, new compositional information comes from a just-obtained map of methane ice across part of Pluto's surface that reveals striking contrasts: Sputnik Planum has abundant methane, while the region informally named Cthulhu Regio shows none, aside from a few isolated ridges and crater rims. Mountains along the west flank of Sputnik lack methane as well.

The distribution of methane across the surface is anything but simple, with higher concentrations on bright plains and crater rims, but usually none in the centers of craters or darker regions.  Outside of Sputnik Planum, methane ice appears to favor brighter areas, but scientists aren’t sure if that’s because methane is more likely to condense there or that its condensation brightens those regions.


Image above: The Ralph/LEISA infrared spectrometer on NASA’s New Horizons spacecraft mapped compositions across Pluto’s surface as it flew by on July 14. On the left, a map of methane ice abundance shows striking regional differences, with stronger methane absorption indicated by the brighter purple colors here, and lower abundances shown in black. Data have only been received so far for the left half of Pluto’s disk. At right, the methane map is merged with higher-resolution images from the spacecraft’s Long Range Reconnaissance Imager (LORRI). Image Credits: NASA/JHUAPL/SWRI.

“It's like the classic chicken-or-egg problem,” said Will Grundy, New Horizons surface composition team lead from Lowell Observatory in Flagstaff, Arizona. “We’re unsure why this is so, but the cool thing is that New Horizons has the ability to make exquisite compositional maps across the surface of Pluto, and that’ll be crucial to resolving how enigmatic Pluto works.”

The Rich Color Variations of Pluto

Image above: NASA’s New Horizons spacecraft captured this high-resolution enhanced color view of Pluto on July 14, 2015. The image combines blue, red and infrared images taken by the Ralph/Multispectral Visual Imaging Camera (MVIC). Pluto’s surface sports a remarkable range of subtle colors, enhanced in this view to a rainbow of pale blues, yellows, oranges, and deep reds. Many landforms have their own distinct colors, telling a complex geological and climatological story that scientists have only just begun to decode. The image resolves details and colors on scales as small as 0.8 miles (1.3 kilometers).  The viewer is encouraged to zoom in on the image on a larger screen to fully appreciate the complexity of Pluto’s surface features. Image Credits: NASA/JHUAPL/SwRI.

“With these just-downlinked images and maps, we’ve turned a new page in the study of Pluto beginning to reveal the planet at high resolution in both color and composition,” added New Horizons Principal Investigator Alan Stern, of SwRI. “I wish Pluto’s discoverer Clyde Tombaugh had lived to see this day.”

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

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

Greetings, Orbiter.ch

Fish reveal details of bone density loss during space missions








JAXA - Japan Aerospace Exploration Agency logo.

September 24, 2015

Studies of medaka fish raised on the International Space Station shed light on how bone responds to sustained exposure to microgravity.

Spending time in space in a reduced gravity environment can have lasting effects on the body. For example, it is known that gravity plays a key role in the correct formation and maintenance of bone structure. Studies have shown that astronauts experience a significant drop in bone mineral density when they have been on space missions, but the exact molecular mechanisms responsible for this are unclear.

Now, Akira Kudo at Tokyo Institute of Technology, together with scientists across Japan, have shown that medaka fish reared on the International Space Station for 56 days experienced increased osteoclast activity – bone cells involved in the re-absorption of bone tissue - likely leading to a subsequent reduction of bone density. They also found several genes that were upregulated in the fish during the space mission.

The team generated fish with osteoclasts that emit a fluorescent signal. They sent 24 fish into space as juveniles, and monitored their development for 56 days under microgravity. The results were compared with a fish control group kept on Earth.

Figure

Scientists at Tokyo Institute of Technology have shown how osteoclast volume and activity is enhanced in the upper and lower jaw bones of medaka fish after 56 days spent on the International Space Station. The team found subsequent reduction in bone density in the space fish compared with a control group of fish kept on Earth.
Reference

Kudo and his team found that bone mineral density in the pharyngeal bone (the jaw bone at the back of the throat) and the teeth of the fish reduced significantly, with decreased calcification by day 56 compared with the control group. This thinning of bone was accompanied by an increase in the volume and activity of osteoclasts. The team conducted whole transcriptome analysis of the fish jaws, and uncovered two strongly upregulated genes (fkbp5 and ddit4), together with 15 other mitochondria-related genes whose expression was also enhanced.

Reduced movement under microgravity also has an influence. The fish began to exhibit unusual behavior towards the latter stages of their stay in space, showing motionless at day 47.

International Space Station (ISS) during STS-134 Mission

The findings provide valuable details of bone structure physiology and the abnormalities caused by the stress to the body at reduced gravity.

Background

The impact of reduced gravity on bone tissues

Time spent in so-called ‘microgravity’ environments – where the force of gravity is considerably less than on Earth – can cause significant problems for the human body. Astronauts who spend a number of weeks in space have been shown to suffer from reduced bone mineral density, leading to skeletal problems. Other issues include problems with skin structure and a reduced ability to heal when wounded.

The precise molecular mechanisms responsible for loss of bone density are not yet fully understood. The current study by Kudo and his team is a first step towards uncovering the reasons why bone structure is affected. Their results show that osteoclast formation and activity in medaka fish increased after they spent more than two weeks in a microgravity environment. Osteoclasts are responsible for the re-absorption of bone tissue, resulting in demineralisation and decalcification of the skeleton.

Methodology

Kudo and his team generated 312 modified fish whose osteoclasts and osteoblasts (cells responsible for bone formation) would emit two different fluorescent signals when activated. They sent 24 of the healthiest fish on a 56-day mission to the International Space Station (ISS), and retained a control group of modified fish on Earth.

The fish on the space station were filmed for the full two-month period in order to record unusual behavior stemming from time spent at reduced gravity. With help of the astronauts aboard the ISS, the team extracted genetic material from the fish at different stages of the process, alongside monitoring osteoclast/osteoblast activity. They performed X-ray analysis of the bones of the fish at day 56 to ascertain mineral density changes. Growth was also monitored, although overall growth tendencies remained the same regardless of gravity changes.

Future work

This study highlights the stress caused to bone structure (and the subsequent knock-on effects on functional ability) by microgravity. The researchers liken the situation to disuse osteoporosis on the ground. Their findings hold implications for longer space missions and the impact of microgravity on the human body.

Authors:

Masahiro Chatani, Akiko Mantoku, Kazuhiro Takeyama, Dawud Abduweli, Yasutaka Sugamori, Kazuhiro Aoki, Keiichi Ohya, Hiromi Suzuki, Satoko Uchida, Toru Sakimura, Yasushi Kono, Fumiaki Tanigaki, Masaki Shirakawa, Yoshiro Takano and Akira Kudo.

Title of original paper:

Microgravity promotes osteoclast activity in medaka fish reared at the international space station: http://www.nature.com/articles/srep14172

Journal:

Scientific Reports 5 (14172) (2015). DOI: 10.1038/srep14172.

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

Images, Text, Credits: Japan Aerospace Exploration Agency (JAXA)/National Research and Development Agency/Tokyo Institute of Technology/NASA.

Greetings, Orbiter.ch

Revisiting the Veil Nebula












ESA - Hubble Space Telescope logo.

24 September 2015

Revisiting the Veil Nebula

The NASA/ESA Hubble Space Telescope imaged three magnificent sections of the Veil Nebula in 1997. Now, a stunning new set of images from Hubble’s Wide Field Camera 3 capture these scattered stellar remains in spectacular new detail and reveal its expansion over the last years.

The Veil Nebula (ground-based view)

Deriving its name from its delicate, draped filamentary structures, the beautiful Veil Nebula is one of the best-known supernova remnants. It formed from the violent death of a star twenty times the mass of the Sun that exploded about 8000 years ago. Located roughly 2100 light-years from Earth in the constellation of Cygnus (The Swan), this brightly coloured cloud of glowing debris spans approximately 110 light-years.

3D image of the Veil Nebula

In 1997, Hubble’s Wide Field and Planetary Camera 2 (WFPC2) photographed the Veil Nebula, providing detailed views of its structure. Now, overlaying WFPC2 images with new Wide Field Camera 3 (WFC3) data provides even greater detail and allows scientists to study how far the nebula has expanded since it was photographed over 18 years ago.

Stereo image of the Veil Nebula

Despite the nebula’s complexity and distance from us, the movement of some of its delicate structures is clearly visible — particularly the faint red hydrogen filaments. In this image, one such filament can be seen as it meanders through the middle of the brighter features that dominate the image.

video
Zooming in on the Veil Nebula

Astronomers suspect that before the Veil Nebula’s source star exploded it expelled a strong stellar wind. This wind blew a large cavity into the surrounding interstellar gas. As the shock wave from the supernova expands outwards, it encounters the walls of this cavity — and forms the nebula’s distinctive structures. Bright filaments are produced as the shock wave interacts with a relatively dense cavity wall, whilst fainter structures are generated by regions nearly devoid of material. The Veil Nebula’s colourful appearance is generated by variations in the temperatures and densities of the chemical elements present.

video
Panning across the Veil Nebula

The blue coloured features — outlining the cavity wall — appear smooth and curved in comparison to the fluffy green and red coloured ones. This is because the gas traced by the blue filter has more recently encountered the nebula’s shock wave, thus still maintain the original shape of the shock front. These features also contain hotter gas than the red and green coloured ones [1]. The latter excited longer ago and have subsequently diffused into more chaotic structures.

video
Moving filaments of the Veil Nebula

Hidden amongst these bright, chaotic structures lie a few thin, sharply edged, red coloured filaments. These faint hydrogen emission features are created through a totally different mechanism than that which generates their fluffy red companions, and they provide scientists with a snapshot of the shock front. The red colour arises after gas is swept into the shock wave — which is moving at almost 1.5 million kilometres per hour! — and the hydrogen within the gas is excited by particle collisions right at the shock front itself.

Hubble Space Telescope

Despite utilising six full Hubble fields of view, these new WFC3 images cover just a tiny fraction of the nebula’s outer limb. Located on the west side of the supernova remnant, this section of the outer shell is in a region known as NGC 6960 or — more colloquially — the Witch’s Broom Nebula.

Notes:

[1] The colours in the image have been chosen to help identifying the three different species of gas; they do not represent the real colours of the nebula.

Notes for editors:

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/

Link to HubbleSite release: http://hubblesite.org/newscenter/archive/releases/2015/29

Uncovering the Veil nebula: https://www.spacetelescope.org/news/heic0712/

NASA release: http://www.nasa.gov/image-feature/veil-nebula-supernova-remnant

Related links:

Hubble’s Wide Field and Planetary Camera 2 (WFPC2): https://en.wikipedia.org/wiki/Wide_Field_and_Planetary_Camera_2

Hubble’s Wide Field Camera 3 (WFC3): https://www.spacetelescope.org/about/general/instruments/wfc3/

Image credit: NASA, ESA, Hubble Heritage Team/Digitized Sky Survey 2.

Greetings, Orbiter.ch

Forty years of European space tracking








ESA - European Space Agency patch.

24 September 2015

Today, ESA celebrates the 40th anniversary of the Agency’s ground station network, the indispensable link to spacecraft that are helping us to learn about our planet, our Solar System and our Universe.

Over four decades, Estrack has expanded globally and today employs cutting-edge technology to link scientists and mission controllers with spacecraft orbiting Earth, watching our Sun, studying stars and voyaging deep into our Solar System.

Celebrating at Cebreros

Estrack has stations on three continents, all remotely operated from the European Space Operations Centre in Darmstadt, Germany. The network is now tracking more than a dozen science and Earth observation missions, including Swarm, the Sentinels, Rosetta, Gaia and Mars Express.

Celebrating European spacecraft tracking

The anniversary was celebrated in a ceremony at the Cebreros deep-space station, near Madrid, today.

In the presence of invited dignitaries and media, ESA’s Director for Human Spaceflight and Operations, Thomas Reiter, welcomed guest speakers Alvaro Giménez, ESA’s Director of Science and Robotic Exploration, Valeriano Claros-Guerra, the former Director of Villafranca Tracking Station, and Alaudin Bhanji, project manager for NASA’s Deep Space Network.

Cebreros station

“With the strong and continuous support of European industry, the network’s technological capability is evolving to meet the increasing operational requirements of future science and Earth missions,” noted Thomas Reiter.

“This includes the capability to determine the position of spacecraft millions of kilometres away from our planet with extremely high precision, which is crucial, for example, for missions like Rosetta, and perform radio science with a number of missions including Mars Express.”

Going to Jupiter

In the near future, Estrack deep-space stations will provide crucial support for European missions to Mars, Mercury, Jupiter and its moons and our Sun.

Returning scientific data from deep space

With the 2012 inauguration of a third 35 m-diameter antenna, at Malargüe, Argentina, joining the others at New Norcia, Australia, and Cebreros, Spain, Estrack achieved global deep-space coverage.

These stations can communicate with spacecraft orbiting out to some 800 million km.

“ESA ground stations and their superb technology are indispensable for space scientists, who could not do their research without the reliable return of precious data,” said Alvaro Giménez.

“Whether downloading images of a 4.5 billion-year-old comet, fundamental physical data about black holes or a map showing our Universe just after birth, Estrack provides the links to spacecraft travelling to the frontiers of human knowledge.”

Estrack40 music video

Guests at the event were treated to the first showing of a music video composed especially for the 40th anniversary, the audio of which was selected from among 117 entries in an international competition via Sound Cloud.

video
Ground station chillax

The composer, Gautier Acher, aged 17, from Paris, was invited to introduce his work and view first hand the impressive dish at Cebreros. His music will now be adopted as the official Estrack theme.

Made-in-Europe expertise

Over the decades, some of the world’s best tracking technology has been developed, from cryogenically cooled amplifiers to digital signal processors, and precision pointing systems.

“This has allowed European industry to spin off technology developed through ESA into global commercial markets and gain a strong competitive advantage,” said Klaus-Juergen Schulz, responsible for ESA’s station technology development.

Estrack's challenging evolution

To download increased amounts of science data, stations will be upgraded to use higher frequencies, the latest-technology beam waveguide systems and highly accurate signal acquisition aids.

ESA will also exploit next-generation technologies such as laser links and creating arrays of antennas.

The network is already adapting to expected future demands, taking into consideration the growing capabilities of commercial services.

Estrack’s advanced capabilities are enabling ESA to share tracking capacity with other space agencies, who respond in kind for ESA missions. Estrack regularly supports missions from the US, Europe, Japan, Russia and China.

More information esa.int/estrack: http://www.esa.int/Our_Activities/Operations/Estrack

Related links:

Cebreros deep-space station: http://www.esa.int/Our_Activities/Operations/Estrack/Cebreros_-_DSA_2

Cebreros webcam: http://www.esa.int/Our_Activities/Operations/Estrack/ESTRACK_Cebreros_webcam

Malargüe webcam: http://www.esa.int/Our_Activities/Operations/Estrack/ESTRACK_Malarguee_webcam

Images, Video, Text, Credits: ESA/Guillermo Cruzado/S. Marti/AOES.

Best regards, Orbiter.ch