vendredi 29 janvier 2016

New Animation Takes a Colorful Flight Over Ceres












NASA - Dawn Mission patch.

Jan. 29, 2016

video
Flight Over Dwarf Planet Ceres

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

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

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

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

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

Ceres flyover

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

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

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

http://dawn.jpl.nasa.gov/mission

More information about Dawn is available at the following sites:

http://dawn.jpl.nasa.gov

http://www.nasa.gov/dawn

Image, Video, Text, Credits: NASA/Tony Greicius/JPL/Elizabeth Landau.

Greetings, Orbiter.ch

Hubble Finds Misbehaving Spiral

NASA - Hubble Space Telescope patch.

Jan. 29, 2016


Despite its unassuming appearance, the edge-on spiral galaxy captured in the left half of this NASA/ESA Hubble Space Telescope image is actually quite remarkable.

Located about one billion light-years away in the constellation of Eridanus, this striking galaxy — known as LO95 0313-192 — has a spiral shape similar to that of the Milky Way. It has a large central bulge, and arms speckled with brightly glowing gas mottled by thick lanes of dark dust. Its companion, sitting in the right of the frame, is known rather unpoetically as [LOY2001] J031549.8-190623.

Jets, outbursts of superheated gas moving at close to the speed of light, have long been associated with the cores of giant elliptical galaxies, and galaxies in the process of merging. However, in an unexpected discovery, astronomers found LO95 0313-192, even though it is a spiral galaxy, to have intense radio jets spewing out from its center. The galaxy appears to have two more regions that are also strongly emitting in the radio part of the spectrum, making it even rarer still.

The discovery of these giant jets in 2003 — not visible in this image, but indicated in this earlier Hubble composite — has been followed by the unearthing of a further three spiral galaxies containing radio-emitting jets in recent years. This growing class of unusual spirals continues to raise significant questions about how jets are produced within galaxies, and how they are thrown out into the cosmos.

For images and more information about Hubble, visit:

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

Text credits: ESA (European Space Agency)/Rob Garner/Image credits: ESA/Hubble & NASA; acknowledgement, Judy Schmidt.

Greetings, Orbiter.ch

ILS Proton launches Eutelsat-9B satellite















ILS - Eutelsat-9B EDRS satellite launch poster.


Jan. 29, 2016

EDRS-A liftoff

The first laser node of the European Data Relay System lifted off from Baikonur, Kazakhstan atop a Proton rocket on 29 January at 22:20 GMT / 4:20 am local time.

ILS Proton launches Eutelsat-9B satellite

Dubbed the ‘SpaceDataHighway’, EDRS will uniquely provide near-realtime Big Data relay services using cutting-edge laser technology. It will dramatically improve access to time-critical data, aiding disaster response by emergency services and maritime surveillance.

Eutelsat-9B satellite or European Data Relay System (EDRS)

Both the Proton launch vehicle and Breeze-M upper stage were designed, and are serially produced, at the Khrunichev Space Center. The modernized Proton-M / Breeze-M upper stage configuration is capable of providing a GTO delivery for payloads with a mass in excess of 6 MT.

For more information about European Data Relay System (EDRS), visit:
http://www.esa.int/Our_Activities/Telecommunications_Integrated_Applications/EDRS

For more information about International Launch Services (ILS), visit:
http://www.ilslaunch.com/

Images, Video, Text, Credits: ILS/Eutelsat/ROSCOSMOS TV/Orbiter.ch Aerospace/Roland Berga.

Best regards, Orbiter.ch

Curiosity Self-Portrait at Martian Sand Dune












NASA - Mars Science Laboratory (MSL) patch.

Jan. 29, 2016


This self-portrait of NASA's Curiosity Mars rover shows the vehicle at "Namib Dune," where the rover's activities included scuffing into the dune with a wheel and scooping samples of sand for laboratory analysis.

The scene combines 57 images taken on Jan. 19, 2016, during the 1,228th Martian day, or sol, of Curiosity's work on Mars. The camera used for this is the Mars Hand Lens Imager (MAHLI) at the end of the rover's robotic arm.

Namib Dune is part of the dark-sand "Bagnold Dune Field" along the northwestern flank of Mount Sharp. Images taken from orbit have shown that dunes in the Bagnold field move as much as about 3 feet (1 meter) per Earth year.

The location of Namib Dune is show on a map of Curiosity's route at http://mars.nasa.gov/msl/multimedia/images/?ImageID=7640. The relationship of Bagnold Dune Field to the lower portion of Mount Sharp is shown in a map at http://photojournal.jpl.nasa.gov/catalog/PIA16064.

The view does not include the rover's arm. Wrist motions and turret rotations on the arm allowed MAHLI to acquire the mosaic's component images. The arm was positioned out of the shot in the images, or portions of images, that were used in this mosaic. This process was used previously in acquiring and assembling Curiosity self-portraits taken at sample-collection sites, including "Rocknest" (http://photojournal.jpl.nasa.gov/catalog/PIA16468), "Windjana" (http://photojournal.jpl.nasa.gov/catalog/PIA18390) and "Buckskin" (http://photojournal.jpl.nasa.gov/catalog/PIA19807).

For scale, the rover's wheels are 20 inches (50 centimeters) in diameter and about 16 inches (40 centimeters) wide.

MAHLI was built by Malin Space Science Systems, San Diego. NASA's Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the Mars Science Laboratory Project for the NASA Science Mission Directorate, Washington. JPL designed and built the project's Curiosity rover.

More information about Curiosity is online at http://www.nasa.gov/msl and http://mars.jpl.nasa.gov/msl/.

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

Greetings, Orbiter.ch

jeudi 28 janvier 2016

Pluto’s Widespread Water Ice & Blue Atmosphere in the Infrared












NASA - New Horizons Mission logo.

Jan. 28, 2016

Pluto’s Widespread Water Ice

New data from NASA’s New Horizons spacecraft point to more prevalent water ice on Pluto’s surface than previously thought.

This false-color image, derived from observations in infrared light by the Ralph/Linear Etalon Imaging Spectral Array (LEISA) instrument, shows where the spectral features of water ice are abundant on Pluto’s surface. It is based on two LEISA scans of Pluto obtained on July 14, 2015, from a range of about 67,000 miles (108,000 kilometers).

The scans, taken about 15 minutes apart, were stitched into a combined multispectral Pluto “data cube” covering the full hemisphere visible to New Horizons as it flew past Pluto. A data cube like this is a three-dimensional array in which an image of Pluto is formed at each LEISA-sensitive wavelength.

Water ice is Pluto's crustal "bedrock,” the canvas on which its more volatile ices paint their seasonally changing patterns. Initial New Horizons maps of Pluto's water ice bedrock compared LEISA spectra with a pure water ice template spectrum, resulting in the map at left.

A disadvantage of that technique is that water ice's spectral signature is easily masked by methane ice, so that map was only sensitive to areas that were especially rich in water ice and/or depleted in methane. The much more sensitive method used on the right involves modeling the contributions of Pluto's various ices all together. This method, too, has limitations in that it can only map ices included in the model, but the team is continually adding more data and improving the model.

The new map shows exposed water ice to be considerably more widespread across Pluto's surface than was previously known — an important discovery. But despite its much greater sensitivity, the map still shows little or no water ice in the informally named places called Sputnik Planum (the left or western region of Pluto’s “heart”) and Lowell Regio (far north on the encounter hemisphere). This indicates that at least in these regions, Pluto's icy bedrock is well hidden beneath a thick blanket of other ices such as methane, nitrogen and carbon monoxide.

Pluto's Blue Atmosphere in the Infrared

This image from NASA’s New Horizons spacecraft is the first look at Pluto’s atmosphere in infrared wavelengths, and the first image of the atmosphere made with data from the New Horizons Ralph/Linear Etalon Imaging Spectral Array (LEISA) instrument.

In this image, sunlight is coming from above and behind Pluto. The image was captured on July 14, 2015, while New Horizons was about 112,000 miles (180,000 kilometers) away. The image covers LEISA’s full spectral range (1.25 to 2.5 microns), which is divided into thirds, with the shortest third being put into the blue channel, middle third into the green channel, and longest into the red channel. North in this image is around the 10 o’clock position.

The blue ring around Pluto is caused by sunlight scattering from haze particles common in Pluto's atmosphere; scientists believe the haze is a photochemical smog resulting from the action of sunlight on methane and other molecules, producing a complex mixture of hydrocarbons such as acetylene and ethylene. These hydrocarbons accumulate into small particles – a fraction of a micrometer in size – which scatter sunlight to make the blue haze. The new infrared image, when combined with earlier images made at shorter, visible wavelengths, gives scientists new clues into the size distribution of the particles.

The whitish patches around Pluto’s limb in this image are sunlight bouncing off more reflective or smoother areas on Pluto's surface – with the largest patch being the western section of the informally named Cthulhu Regio. Future LEISA observations returned to Earth should capture the remainder of the haze, missing from the lower section of the image.

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

Images, Text, Credits: NASA/JHUIAPL/SwRI/Tricia Talbert.

Greetings, Orbiter.ch

Hubble Sees Monstrous Cloud Boomerang Back to our Galaxy











NASA - Hubble Space Telescope patch.

Jan. 28, 2016

Hubble Space Telescope astronomers are finding that the old adage “what goes up must come down” even applies to an immense cloud of hydrogen gas outside our Milky Way galaxy. The invisible cloud is plummeting toward our galaxy at nearly 700,000 miles per hour.


Image above: This composite image shows the size and location of the Smith Cloud on the sky. The cloud appears in false-color, radio wavelengths as observed by the Green Bank Telescope in West Virginia. The visible-light image of the background star field shows the cloud's location in the direction of the constellation Aquila. Image Credits: Saxton/Lockman/NRAO/AUI/NSF/Mellinger.

Though hundreds of enormous, high-velocity gas clouds whiz around the outskirts of our galaxy, this so-called “Smith Cloud” is unique because its trajectory is well known. New Hubble observations suggest it was launched from the outer regions of the galactic disk, around 70 million years ago. The cloud was discovered in the early 1960s by doctoral astronomy student Gail Smith, who detected the radio waves emitted by its hydrogen.

The cloud is on a return collision course and is expected to plow into the Milky Way’s disk in about 30 million years. When it does, astronomers believe it will ignite a spectacular burst of star formation, perhaps providing enough gas to make 2 million suns.


Images above: This diagram shows the 100-million-year-long trajectory of the Smith Cloud as it arcs out of the plane of our Milky Way galaxy and then returns like a boomerang. Hubble Space Telescope measurements show that the cloud came out of a region near the edge of the galaxy's disk of stars 70 million years ago. The cloud is now stretched into the shape of a comet by gravity and gas pressure. Following a ballistic path, the cloud will fall back into the disk and trigger new star formation 30 million years from now. Image Credits: NASA/ESA/A. Feild (STScI).

“The cloud is an example of how the galaxy is changing with time,” explained team leader Andrew Fox of the Space Telescope Science Institute in Baltimore, Maryland. “It’s telling us that the Milky Way is a bubbling, very active place where gas can be thrown out of one part of the disk and then return back down into another.

"Our galaxy is recycling its gas through clouds, the Smith Cloud being one example, and will form stars in different places than before. Hubble’s measurements of the Smith Cloud are helping us to visualize how active the disks of galaxies are,” Fox said.

Astronomers have measured this comet-shaped region of gas to be 11,000 light-years long and 2,500 light-years across. If the cloud could be seen in visible light, it would span the sky with an apparent diameter 30 times greater than the size of the full moon.

Astronomers long thought that the Smith Cloud might be a failed, starless galaxy, or gas falling into the Milky Way from intergalactic space. If either of these scenarios proved true, the cloud would contain mainly hydrogen and helium, not the heavier elements made by stars. But if it came from within the galaxy, it would contain more of the elements found within our sun.


Image above: Hubble's Cosmic Origins Spectrograph can measure how the light from distant background objects is affected as it passes through the cloud, yielding clues to the chemical composition of the cloud. Astronomers trace the cloud's origin to the disk of our Milky Way. Combined ultraviolet and radio observations correlate to the cloud's infall velocities, providing solid evidence that the spectral features link to the cloud's dynamics. Image Credits: NASA/ESA/A. Feild (STScI).

The team used Hubble to measure the Smith Cloud’s chemical composition for the first time, to determine where it came from. They observed the ultraviolet light from the bright cores of three active galaxies that reside billions of light-years beyond the cloud. Using Hubble’s Cosmic Origins Spectrograph, they measured how this light filters through the cloud.

In particular, they looked for sulfur in the cloud, which can absorb ultraviolet light. “By measuring sulfur, you can learn how enriched in sulfur atoms the cloud is compared to the sun,” Fox explained. Sulfur is a good gauge of how many heavier elements reside in the cloud.

The astronomers found that the Smith Cloud is as rich in sulfur as the Milky Way’s outer disk, a region about 40,000 light-years from the galaxy’s center (about 15,000 light-years farther out than our sun and solar system). This means that the Smith Cloud was enriched by material from stars. This would not happen if it were pristine hydrogen from outside the galaxy, or if it were the remnant of a failed galaxy devoid of stars. Instead, the cloud appears to have been ejected from within the Milky Way and is now boomeranging back.

Though this settles the mystery of the Smith Cloud’s origin, it raises new questions: How did the cloud get to where it is now? What calamitous event could have catapulted it from the Milky Way’s disk, and how did it remain intact? Could it be a region of dark matter — an invisible form of matter — that passed through the disk and captured Milky Way gas? The answers may be found in future research.

The team’s research appears in the Jan. 1, 2016, issue of The Astrophysical Journal Letters.

The Hubble Space Telescope is a project of international cooperation between NASA and the European Space Agency (ESA). 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, D.C.

For images and more information about Hubble, visit:

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

Images (mentioned), Text, Credits: NASA/Ashley Morrow/Space Telescope Science Institute/Ann Jenkins/Ray Villard/Andrew Fox.

Best regards, Orbiter.ch

Martian labyrinth












ESA - Mars Express Mission patch.

28 January 2016

Perspective view in Noctis Labyrinthus

This block of martian terrain, etched with an intricate pattern of landslides and wind-blown dunes, is a small segment of a vast labyrinth of valleys, fractures and plateaus.

The region, known as Noctis Labyrinthus – the “labyrinth of the night” – lies on the western edge of Valles Marineris, the grand canyon of the Solar System. It was imaged by ESA’s Mars Express on 15 July 2015.

It is part of a complex feature whose origin lies in the swelling of the crust owing to tectonic and volcanic activity in the Tharsis region, home to Olympus Mons and other large volcanoes.

Noctis Labyrinthus context

As the crust bulged in the Tharsis province it stretched apart the surrounding terrain, ripping fractures several kilometres deep and leaving blocks – graben – stranded within the resulting trenches.

The entire network of graben and fractures spans some 1200 km, about the equivalent length of the river Rhine from the Alps to the North Sea.

The segment presented here captures a roughly 120 km-wide portion of that network, with one large, flat-topped block taking centre stage.

Noctis Labyrinthus plan view

Landslides are seen in extraordinary detail in the flanks of this unit and along the valley walls (most notable in the perspective view, top), with eroded debris lying at the base of the steep walls.

Noctis Labyrinthus topography

In some places, particularly notable in the lower-right corner of the plan view image (above), wind has drawn the dust into dune fields that extend up onto the surrounding plateaus.

3D view in Noctis Labyrinthus

Near-linear features are also visible on the flat elevated surfaces: fault lines crossing each other in different directions, suggesting many episodes of tectonic stretching in the complex history of this region.

Related links:

Looking at Mars: http://www.esa.int/Our_Activities/Space_Science/Mars_Express

More about...

Mars Express overview: http://www.esa.int/Our_Activities/Space_Science/Mars_Express_overview

Mars Express 10 year brochure: http://esamultimedia.esa.int/multimedia/publications/BR-312/

Images, Text, Credits: ESA/DLR/FU Berlin, CC BY-SA 3.0 IGO/NASA MGS MOLA Science Team.

Best regards, Orbiter.ch

Ariane 5’s first launch of 2016


















Arianespace - Flight VA228 launch poster.


28 January 2016

Ariane 5 liftoff on VA228

An Ariane 5 last night delivered telecom satellite Intelsat-29e into its planned orbit. Liftoff of Ariane flight VA228 occurred on 27 January at 23:20 GMT (20:20 local time, 00:20 CET on 28 January) from Europe’s Spaceport in Kourou, French Guiana.

Intelsat-29e was the sole passenger on this launch. With a mass at liftoff of 6552 kg, it was released about 30 minutes into the mission.

video
Flight VA228: The successful launch of Intelsat 29e, and Ariane 5’s 70th success in a row

Positioned at 50ºW over Brazil in geostationary orbit, the satellite has a design life of 15 years and is the first of a new generation of telecom satellites that will provide the fastest commercially available connectivity to mobile network operators, aero and maritime mobility service providers and government customers. Coverage is the Americas and over the North Atlantic for shipping and aviation routes.

Intelsat 29e satellite

This is the first of two of Intelsat’s next-generation satellites that will be launched by Ariane 5 this year.

Flight VA228 was the 84th Ariane 5 mission.

For more information about Arianespace, visit: http://www.arianespace.com/

Images, Video, Text, Credits: ESA/Arianespace/Günter Space Page.

Greetings, Orbiter.ch

mercredi 27 janvier 2016

The Milky Way’s Clean and Tidy Galactic Neighbour












ESO - European Southern Observatory logo.

27 January 2016

The dwarf galaxy IC 1613

Many galaxies are chock-full of dust, while others have occasional dark streaks of opaque cosmic soot swirling in amongst their gas and stars. However, the subject of this new image, snapped with the OmegaCAM camera on ESO’s VLT Survey Telescope in Chile, is unusual — the small galaxy, named IC 1613, is a veritable clean freak! IC 1613 contains very little cosmic dust, allowing astronomers to explore its contents with great clarity. This is not just a matter of appearances; the galaxy’s cleanliness is vital to our understanding of the Universe around us.

IC 1613 is a dwarf galaxy in the constellation of Cetus (The Sea Monster). This VST image [1] shows the galaxy’s unconventional beauty, all scattered stars and bright pink gas, in great detail.

German astronomer Max Wolf discovered IC 1613’s faint glow in 1906. In 1928, his compatriot Walter Baade used the more powerful 2.5-metre telescope at the Mount Wilson Observatory in California to successfully make out its individual stars. From these observations, astronomers figured out that the galaxy must be quite close to the Milky Way, as it is only possible to resolve single pinprick-like stars in the very nearest galaxies to us.

The dwarf galaxy IC 1613 in the constellation of Cetus

Astronomers have since confirmed that IC 1613 is indeed a member of the Local Group, a collection of more than 50 galaxies that includes our home galaxy, the Milky Way. IC 1613 itself lies just over 2.3 million light-years away from us. It is relatively well-studied due to its proximity; astronomers have found it to be an irregular dwarf that lacks many of the features, such as a starry disc, found in some other diminutive galaxies.

However, what IC 1613 lacks in form, it makes up for in tidiness. We know IC 1613’s distance to a remarkably high precision, partly due to the unusually low levels of dust lying both within the galaxy and along the line of sight from the Milky Way — something that enables much clearer observations [2].

The sky around the dwarf galaxy IC 1613

The second reason we know the distance to IC 1613 so precisely is that the galaxy hosts a number of notable stars of two types: Cepheid variables and RR Lyrae variables [3]. Both types of star rhythmically pulsate, growing characteristically bigger and brighter at fixed intervals (eso1311).

As we know from our daily lives on Earth, shining objects such as light bulbs or candle flames appear dimmer the further they are away from us. Astronomers can use this simple piece of logic to figure out exactly how far away things are in the Universe— so long as they know how bright they really are, referred to as their intrinsic brightness.

video
Zooming in on the dwarf galaxy IC 1613

Cepheid and RR Lyrae variables have the special property that their period of brightening and dimming is linked directly to their intrinsic brightness. So, by measuring how quickly they fluctuate astronomers can work out their intrinsic brightness. They can then compare these values to their apparent measured brightness and work out how far away they must be to appear as dim as they do.

Stars of known intrinsic brightness can act like standard candles, as astronomers say, much like how a candle with a specific brightness would act as a good gauge of distance intervals based on the observed brightness of its flame’s flicker.

video
A close look at the dwarf galaxy IC 1613

Using standard candles — such as the variable stars within IC 1613 and the less-common Type Ia supernova explosions, which can seen across far greater cosmic distances — astronomers have pieced together a cosmic distance ladder, reaching deeper and deeper into space.

Decades ago, IC 1613 helped astronomers work out how to utilise variable stars to chart the Universe’s grand expanse. Not bad for a little, shapeless galaxy.

video
IC1613 Fulldome Flythrough

Notes:

[1] OmegaCAM is a 32-CCD, 256-million-pixel camera mounted on the 2.6-metre VLT Survey Telescope at Paranal Observatory in Chile. To view more images taken by OmegaCAM: http://www.eso.org/public/images/archive/search/?ranking=0&release_id=&minimum_size=0&description=&published_until_year=0&published_until_month=0&title=&instrument=46&subject_name=&credit=&published_until_day=0&published_since_day=0&published_since_month=0&id=&published_since_year=0

[2] Cosmic dust is made of various heavier elements, such as carbon and iron, as well as larger, grainier molecules. Not only does dust block out light, making dust-shrouded objects harder to see, it also preferentially scatters bluer light. As a result, cosmic dust makes objects appear redder when seen through our telescopes than they are in reality. Astronomers can factor out this reddening when studying objects. Still, the less reddening, the more precise an observation is likely to be.

[3] Other than the two Magellanic Clouds, IC 1613 is the only irregular dwarf galaxy in the Local Group in which RR Lyrae type variable stars have been identified.

More information:

ESO is the foremost intergovernmental astronomy organisation in Europe and the world’s most productive ground-based astronomical observatory by far. It is supported by 16 countries: Austria, Belgium, Brazil, the Czech Republic, Denmark, France, Finland, Germany, Italy, the Netherlands, Poland, Portugal, Spain, Sweden, Switzerland and the United Kingdom, along with the host state of Chile. ESO carries out an ambitious programme focused on the design, construction and operation of powerful ground-based observing facilities enabling astronomers to make important scientific discoveries. ESO also plays a leading role in promoting and organising cooperation in astronomical research. ESO operates three unique world-class observing sites in Chile: La Silla, Paranal and Chajnantor. At Paranal, ESO operates the Very Large Telescope, the world’s most advanced visible-light astronomical observatory and two survey telescopes. VISTA works in the infrared and is the world’s largest survey telescope and the VLT Survey Telescope is the largest telescope designed to exclusively survey the skies in visible light. ESO is a major partner in ALMA, the largest astronomical project in existence. And on Cerro Armazones, close to Paranal, ESO is building the 39-metre European Extremely Large Telescope, the E-ELT, which will become “the world’s biggest eye on the sky”.

Related article:

Galaxy Clusters Reveal New Dark Matter Insights
http://orbiterchspacenews.blogspot.ch/2016/01/galaxy-clusters-reveal-new-dark-matter.html

Related links:

German astronomer Max Wolf: https://en.wikipedia.org/wiki/Max_Wolf

German astronomer Walter Baade: https://en.wikipedia.org/wiki/Walter_Baade

Mount Wilson Observatory: https://en.wikipedia.org/wiki/Mount_Wilson_Observatory

eso1311: http://www.eso.org/public/news/eso1311/

Links:

Photos taken with the VST: http://www.eso.org/public/images/archive/search/?adv=&facility=62

Images of the VST:
http://www.eso.org/public/images/archive/search/?adv=subject_name=VLT%20Survey%20Telescope

Images, Text, Credits: ESO/AU and Sky & Telescope/Digitized Sky Survey 2. Acknowledgement: Davide De Martin/Videos: ESO/A. Fujii/Digitised Sky Survey 2. Music: Johan B. Monell (www.johanmonell.com)/T. Matsopoulos.

Best regards, Orbiter.ch

mardi 26 janvier 2016

Microcosm: the story of CERN












CERN - European Organization for Nuclear Research logo.

Jan. 26, 2016


Image above: The full-scale audio-visual screens in the new microcosm exhibition showcase the people behind the science at CERN, as they explain to the visitors what they do. (Image: Sophia Bennett/CERN).

The new microcosm exhibition takes CERN visitors on a journey through the laboratory’s key installations, following the path of the particles from the bottle of hydrogen, through the network of accelerators and on to collision inside vast experiments.

Objects, life-sized audio-visuals and high-definition photographs are used to recreate real CERN spaces, while live data feeds bring news of the Large Hadron Collider direct to the exhibitions.

Throughout the 500m2 of exhibitions, the focus is on the people who design and use this extraordinary technology to further our understanding of the universe.

video
CERN's new microcosm exhibition is now open

Video above: This time-lapse video shows how microcosm exhibition was constructed and completed (Video: Julien Ordan/CERN).

Microcosm underwent a major revamp in 2015 before fully reopening this January. Screen content continues to evolve and more games will be introduced into the exhibition during 2016.

The exhibition is free and open to all without reservation and visitors are encouraged to share their #microcosm @CERN experiences on social media.

For more details, including opening hours see the microcosm website:
http://microcosm.web.cern.ch/en

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 link:

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

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

Image (mentioned), Video (mentioned), Text, Credits: CERN/Kate Kahle/Corinne Pralavorio.

Greetings, Orbiter.ch

Integral X-Rays Earth's Aurora












ESA - Integral Mission patch.

26 January 2016

Normally busy with observing high-energy black holes, supernovas and neutron stars, ESA’s Integral space observatory recently had the chance to look back at our own planet’s aurora.

Auroras are well known as the beautiful light shows at polar latitudes as the solar wind interacts with Earth’s magnetic field.

As energetic particles from the Sun are drawn along Earth’s magnetic field, they collide with different molecules and atoms in the atmosphere to create dynamic, colourful light shows in the sky, typically in green and red.

But what may be less well known is that auroras also emit X-rays, generated as the incoming particles decelerate.

Integral detected high-energy auroral X-rays on 10 November 2015 as it turned to Earth – although it was looking for something else at the time.

Integral’s X-ray view of Earth’s aurora

Its task was to measure the diffuse cosmic X-ray background that arises naturally from supermassive black holes that are gobbling up material at the centres of some galaxies.

To achieve this, Integral records the X-ray brightness with and without the Earth in the way, blocking the background. These types of measurements help astronomers estimate how many distant supermassive black holes there are in the Universe.

Unfortunately, on this occasion, the X-rays from Earth’s aurora drowned out the cosmic background – but the observations were not a waste.

They also help us to understand the distribution of electrons raining into Earth’s upper atmosphere, and they reveal interactions between the solar wind and Earth’s protective magnetic bubble, or magnetosphere.

“Auroras are transient, and cannot be predicted on the timeframe that satellite observations are planned, so it was certainly an unexpected observation,” comments Erik Kuulkers, Integral project scientist.

“It’s also quite unusual for us to point the spacecraft at Earth: it requires innovative planning by the operations teams to coordinate such a dedicated set of manoeuvres to ensure it can operate safely with Earth inside the instruments’ field of view and then return to its standard observing programme.

 Artist's view of Integral

“Although the original background X-ray measurements didn’t go quite to plan this time, it was exciting to capture such intense auroral activity by chance.”

Related links:

ESA's INTErnational Gamma-Ray Astrophysics Laboratory (Integral): http://sci.esa.int/integral/

Integral in depth: http://sci.esa.int/science-e/www/area/index.cfm?fareaid=21

Images, Text, Credits: ESA/Integral/ E. Churazov (IKI/MPA)/ M. Türler (ISDC/Univ. of Geneva).

Best regards, Orbiter.ch

lundi 25 janvier 2016

Galaxy Clusters Reveal New Dark Matter Insights











NASA logo.

Jan. 25, 2016


Image above: This image from NASA's Hubble Space Telescope shows the inner region of Abell 1689, an immense cluster of galaxies. Scientists say the galaxy clusters we see today have resulted from fluctuations in the density of matter in the early universe. Image Credits: NASA/ESA/JPL-Caltech/Yale/CNRS.

Dark matter is a mysterious cosmic phenomenon that accounts for 27 percent of all matter and energy. Though dark matter is all around us, we cannot see it or feel it. But scientists can infer the presence of dark matter by looking at how normal matter behaves around it.

Galaxy clusters, which consist of thousands of galaxies, are important for exploring dark matter because they reside in a region where such matter is much denser than average. Scientists believe that the heavier a cluster is, the more dark matter it has in its environment. But new research suggests the connection is more complicated than that. 

"Galaxy clusters are like the large cities of our universe. In the same way that you can look at the lights of a city at night from a plane and infer its size, these clusters give us a sense of the distribution of the dark matter that we can't see," said Hironao Miyatake at NASA's Jet Propulsion Laboratory, Pasadena, California.

A new study in Physical Review Letters, led by Miyatake, suggests that the internal structure of a galaxy cluster is linked to the dark matter environment surrounding it. This is the first time that a property besides the mass of a cluster has been shown to be associated with surrounding dark matter.

Researchers studied approximately 9,000 galaxy clusters from the Sloan Digital Sky Survey DR8 galaxy catalog, and divided them into two groups by their internal structures: one in which the individual galaxies within clusters were more spread out, and one in which they were closely packed together. The scientists used a technique called gravitational lensing -- looking at how the gravity of clusters bends light from other objects -- to confirm that both groups had similar masses.

But when the researchers compared the two groups, they found an important difference in the distribution of galaxy clusters. Normally, galaxy clusters are separated from other clusters by 100 million light-years on average. But for the group of clusters with closely packed galaxies, there were fewer neighboring clusters at this distance than for the sparser clusters. In other words, the surrounding dark-matter environment determines how packed a cluster is with galaxies.


Images above: This comparison of galaxy clusters from the Sloan Digital Sky Survey DR8 galaxy catalog shows a spread-out cluster (left) and a more densely-packed cluster (right). A new study shows that these differences are related to the surrounding dark-matter environment. Images Credits: Sloan Digital Sky Survey.

"This difference is a result of the different dark-matter environments in which the groups of clusters formed. Our results indicate that the connection between a galaxy cluster and surrounding dark matter is not characterized solely by cluster mass, but also its formation history," Miyatake said. 

Study co-author David Spergel, professor of astronomy at Princeton University in New Jersey, added, “Previous observational studies had shown that the cluster’s mass is the most important factor in determining its global properties. Our work has shown that ‘age matters': Younger clusters live in different large-scale dark-matter environments than older clusters.”

The results are in line with predictions from the leading theory about the origins of our universe. After an event called cosmic inflation, a period of less than a trillionth of a second after the big bang, there were small changes in the energy of space called quantum fluctuations. These changes then triggered a non-uniform distribution of matter. Scientists say the galaxy clusters we see today have resulted from fluctuations in the density of matter in the early universe.

"The connection between the internal structure of galaxy clusters and the distribution of surrounding dark matter is a consequence of the nature of the initial density fluctuations established before the universe was even one second old," Miyatake said.

Researchers will continue to explore these connections.

“Galaxy clusters are remarkable windows into the mysteries of the universe. By studying them, we can learn more about the evolution of large-scale structure of the universe, and its early history, as well as dark matter and dark energy," Miyatake said.

Related links:

Dark Energy and Dark Matter: http://www.nasa.gov/subject/6891/dark-energy-and-dark-matter/

Galaxies: http://www.nasa.gov/subject/6894/galaxies

Universe: http://www.nasa.gov/topics/solarsystem/index.html

Images (mentioned), Text, Credits: NASA/JPL/Elizabeth Landau/Tony Greicius.

Best regards, Orbiter.ch

Cassini Heads for 'Higher Ground' at Saturn












NASA - Cassini Mission to Saturn patch.

Jan. 25, 2016

NASA's Cassini mission is entering its next chapter with an orbital choreography meant to tilt the spacecraft's orbit out of Saturn's ringplane.

The second of five large propulsive maneuvers in this campaign took place on Saturday, Jan. 23. Each maneuver in the series sets up a subsequent gravity-assist flyby of Saturn's massive moon Titan, which reshapes the spacecraft's orbit, sending it to increasingly higher inclination with respect to Saturn's equator.

The 35-second engine burn began at 2:47 p.m. PST (5:47 p.m. EST) on Jan. 23, and  changed Cassini's orbital speed around Saturn by about 22.3 feet per second (6.8 meters per second).

For comparison, the Feb. 1 encounter with Titan that follows this engine firing will change the velocity by 2,539 feet per second (774 meters per second).

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

Artist's view of the Cassini spacecraft

Cassini will not return again to an orbit near the plane of the rings. Engineers are slowly increasing the tilt of the spacecraft's orbit with respect to Saturn's equator to set up the mission's final, dramatic year. By late November, the spacecraft will be on a path that will carry it high above Saturn's poles, approaching just outside the planet's main rings -- a period the mission team calls the "F-ring orbits." After 20 F-ring orbits, Cassini will begin its Grand Finale event, in which the spacecraft will pass 22 times between the innermost rings and the planet before plunging into Saturn's atmosphere to end its journey on Sept. 15, 2017.

Cassini has been in an equatorial orbit around Saturn since spring 2015, when it began its final campaign of close encounters with the planet's large, icy moons. These flybys included the mission's last close brushes with Hyperion, Dione and Enceladus.

The mission began its current push toward higher inclinations with a burn on Dec. 30 that changed the spacecraft's speed by 9.8 feet per second (3 meters per second) in preparation for a Titan flyby on Jan. 15. Another large main engine maneuver, designed to result in a velocity change of 26.08 feet per second (7.95 meters per second), is planned for March 25, and sets up a Titan flyby on April 4.

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

The Cassini-Huygens mission is a cooperative project of NASA, ESA (European Space Agency) and the Italian Space Agency. JPL manages the mission for NASA's Science Mission Directorate in Washington.

For more information about Cassini, visit:

http://www.nasa.gov/cassini

http://saturn.jpl.nasa.gov

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

Image, Text, Credits: NASA/JPL/Preston Dyches/Tony Greicius.

Best regards, Orbiter.ch

Mars Rover Opportunity Busy Through Depth of Winter











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

Jan. 25, 2016

NASA's senior Mars rover, Opportunity, worked through the lowest-solar-energy days of the mission's seventh Martian winter, while using a diamond-toothed rock grinder and other tools in recent weeks to investigate clues about the Red Planet's environmental history.

The modern Mars environment lent a hand, providing wind that removed some dust from Opportunity's solar panels in the weeks before and after the Mars southern hemisphere's winter solstice on Jan. 2.

"Opportunity has stayed very active this winter, in part because the solar arrays have been much cleaner than in the past few winters," said Mars Exploration Rover Project Manager John Callas, of NASA's Jet Propulsion Laboratory, Pasadena, California.

With the winter solstice over, the amount of sunshine available to Opportunity will continue to increase for most of 2016.


Image above: The target beneath the tool turret at the end of the rover's robotic arm in this image from NASA's Mars Exploration Rover Opportunity is "Private John Potts." It lies high on the southern side of "Marathon Valley," which slices through the western rim of Endeavour Crater. Image Credits: NASA/JPL-Caltech.

The mission has just passed the 12th anniversary of its bouncy, hole-in-one landing on Mars. It landed on Jan. 24, 2004, PST (early Jan. 25, UTC). After the air-bag-cushioned craft stopped rolling inside Eagle Crater, which is about 72 feet (22 meters) in diameter, it opened to release the rover. Inspection of rocks in Eagle Crater during the originally planned mission of three months yielded evidence of wet, acidic environmental conditions on ancient Mars.

Researchers used Opportunity to examine a series of larger and ever more distant craters over the next few years, for access to deeper and older layers of Mars' history.

Each Martian year lasts about 1.9 Earth years. Because Mars is farther from the sun, it takes longer to complete each orbit. The north-south spin axis of Mars is tilted like Earth's, so Mars has summer and winter seasons, too. They are about twice as long as the seasons on Earth, though. That's why, 12 Earth years after Opportunity's landing, the rover is enduring its seventh Martian winter.

Opportunity has been exploring the western rim of a 14-mile-wide (22-kilometer-wide) crater named Endeavour since 2011. This winter, it is examining rocks on the southern side of "Marathon Valley," which slices through Endeavor Crater's rim from west to east. This is a location where observations by NASA's Mars Reconnaissance Orbiter have mapped concentrations of clay minerals that would have formed under wet, non-acidic conditions.

Researchers used Opportunity's rock abrasion tool this month to remove surface crust from a rock target called "Private John Potts." (The team is using names of members of the Lewis and Clark Expedition's Corps of Discovery as informal names for targets in Marathon Valley.) The composition and texture of the rock's exposed interior have been examined with instruments on Opportunity's robotic arm.

Artist's view of Mars Exploration Rover "Opportunity"

The winter work area on the valley's south side keeps the rover's solar panels tilted toward the sun crossing the northern sky. The benefits of dust-clearing events and the strategy of choosing winter locations on north-facing slopes are two key factors in extending Opportunity's productive career 48 times longer, so far, than the originally planned mission of three months after landing.

The solar panels are currently generating more than 460 watt hours per day. That is up about 40 percent from earlier in this Martian winter, but Opportunity has been able to conduct power-intensive operations such as driving and rock-grinding throughout the winter. By contrast, during Opportunity's first Martian winter on the Endeavour rim, power generation dipped below 300 watt-hours for more than two months, and the mission refrained from driving or rock-grinding for more than four months.

"With healthy power levels, we are looking forward to completing the work in Marathon Valley this year and continuing onward with Opportunity," Callas said.

For more information about Opportunity, visit:

http://www.nasa.gov/rovers

http://marsrovers.jpl.nasa.gov

Images, Text, Credits: NASA/Dwayne Brown/Laurie Cantillo/Tony Greicius/JPL/Guy Webster.

Best regards, Orbiter.ch

A Half-Enceladus










NASA - Cassini International logo.

Jan. 25, 2016


This half-lit view of Enceladus bears a passing resemblance to similar views of Earth's own natural satellite, but the similarities end there. Earth's rocky moon is covered in dark, volcanic basins and brighter, mountainous highlands -- both exceedingly ancient. The surface of icy Enceladus is uniformly bright, far brighter than Earth's moon. Large areas of Enceladus' surface are characterized by youthful (on geologic timescales), wrinkled terrains.

Although the north pole of Enceladus (313 miles or 504 kilometers across) was dark when Cassini arrived at Saturn, the march of the seasons at Saturn have brought sunlight to the north and taken it from the south.

This view looks toward the leading hemisphere of Enceladus. North on Encealdus is up. The image was taken in visible light with the Cassini spacecraft narrow-angle camera on Sept. 8, 2015.

The view was acquired at a distance of approximately 80,000 miles (129,000 kilometers) from Enceladus. Image scale is 2,530 feet (772 meters) per pixel.

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

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

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

Greetings, Orbiter.ch

Exploring Imhotep












ESA - Rosetta Mission patch.

Jan. 25, 2016


This beautiful landscape feels within arm’s reach in this stunning view across the Imhotep region on Comet 67P/Churyumov–Gerasimenko.

The view was captured by Rosetta’s OSIRIS narrow-angle camera on 17 January 2016, from a distance of 86.8 km. Measuring 3.2 km across, it captures one of the most geologically diverse areas of the comet.

Imhotep is perhaps most easily identified by the broad smooth area that occupies the centre-right portion of this view. This smooth dusty terrain, which covers about 0.8 sq km, is etched with curvilinear features stretching hundreds of metres and which have been found to change in appearance over time.

Many large boulders are also seen scattered within the smooth terrain, including the boulder Cheops in the foreground. Smaller but more numerous boulders are associated with exposed cliff faces and are most likely the product of erosion. In some debris falls, detailed analysis has revealed the presence of water ice.

Particularly eye-catching is the distinctive layered and fractured material to the left of centre in the background. Similar patterns are also seen in the exposed cliff-like faces towards the right of the scene too, where Imhotep transitions into the Khepry region.

Layers like this are seen in various locations on the comet and scientists are trying to understand how they might be related to the comet’s formation and/or evolution.

Just in front of the prominent left-hand stack of layers a number of small round features can be found. They have a well-defined rim with a smooth interior and appear slightly raised from the surrounding material. One explanation for their appearance is that they are ancient sites of active regions covered by dust and are now being revealed by varying erosion of the overlying layers.

Further in the foreground again and a relatively smooth ‘pathway’ appears to lead towards a more consolidated summit. To the left of this path is the Ash region, while the sheer apex at the top left of the view marks the boundary with Apis.

Use the comet viewer tool to aid navigation around the comet’s regions:  http://sci.esa.int/comet-viewer/

For more information about Rosetta mission, visit: http://www.esa.int/Our_Activities/Space_Science/Rosetta

Rosetta overview: http://www.esa.int/Our_Activities/Space_Science/Rosetta_overview

Rosetta in depth:http://sci.esa.int/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

Rosetta factsheet: http://www.esa.int/Our_Activities/Space_Science/Rosetta/Rosetta_factsheet

Frequently asked questions: http://www.esa.int/Our_Activities/Space_Science/Rosetta/Frequently_asked_questions

Image, Text, Credits: ESA/Rosetta/MPS for OSIRIS Team MPS/UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA.

Greetings, Orbiter.ch

dimanche 24 janvier 2016

Blue Origin - Launch. Land. Repeat.








Blue Origin logo.

Jan 24, 2016


Image above: The same New Shepard booster that flew to space and then landed vertically in November 2015 has now flown and landed again. Image Credit: Blue Origin.

On January 22, 2016 the very same New Shepard booster that flew above the Karman line and then landed vertically at its launch site last November has now flown and landed again, demonstrating reuse. This time, New Shepard reached an apogee of 333,582 feet (101.7 kilometers) before both capsule and booster gently returned to Earth for recovery and reuse.

video
Launch. Land. Repeat.

Data from the November mission matched our preflight predictions closely, which made preparations for today’s re-flight relatively straightforward. The team replaced the crew capsule parachutes, replaced the pyro igniters, conducted functional and avionics checkouts, and made several software improvements, including a noteworthy one. Rather than the vehicle translating to land at the exact center of the pad, it now initially targets the center, but then sets down at a position of convenience on the pad, prioritizing vehicle attitude ahead of precise lateral positioning. It’s like a pilot lining up a plane with the centerline of the runway. If the plane is a few feet off center as you get close, you don’t swerve at the last minute to ensure hitting the exact mid-point. You just land a few feet left or right of the centerline. Our Monte Carlo sims of New Shepard landings show this new strategy increases margins, improving the vehicle’s ability to reject disturbances created by low-altitude winds.


Image above: After a clean separation from the propulsion module, the New Shepard crew capsule descends to a gentle landing in the west Texas desert. Image Credit: Blue Origin.

Though wings and parachutes have their adherents and their advantages, I’m a huge fan of rocket-powered vertical landing. Why? Because — to achieve our vision of millions of people living and working in space — we will need to build very large rocket boosters. And the vertical landing architecture scales extraordinarily well. When you do a vertical landing, you’re solving the classic inverted pendulum problem, and the inverted pendulum problem gets a bit easier as the pendulum gets a bit bigger. Try balancing a pencil on the tip of your finger. Now try it with a broomstick. The broomstick is simpler because its greater moment of inertia makes it easier to balance. We solved the inverted pendulum problem on New Shepard with an engine that dynamically gimbals to balance the vehicle as it descends. And since New Shepard is the smallest booster we will ever build, this carefully choreographed dance atop our plume will just get easier from here. We’re already more than three years into development of our first orbital vehicle. Though it will be the small vehicle in our orbital family, it’s still many times larger than New Shepard. I hope to share details about this first orbital vehicle this year.


Image above: Blue Origin's New Shepard booster executes a controlled vertical landing at 4,2 mph. Image Credit: Blue Origin.

Also this year, we’ll start full-engine testing of the BE-4 and launch and land our New Shepard rocket – again and again. If you want to stay up to date with all the interesting work that our team is doing, sign up for email updates at http://www.blueorigin.com/interested.

For more information about Blue Origin, visit: https://www.blueorigin.com/

Images (mentioned), Video, Text, Credits: Blue Origin.

Best regards, Orbiter.ch