samedi 11 juillet 2015

New Horizons’ Last Portrait of Pluto’s Puzzling Spots












NASA - New Horizons Mission logo.

July 11, 2015


Image caption: New Horizons' last look at Pluto's Charon-facing hemisphere reveals intriguing geologic details that are of keen interest to mission scientists. This image, taken early the morning of July 11, 2015, shows newly-resolved linear features above the equatorial region that intersect, suggestive of polygonal shapes. This image was captured when the spacecraft was 2.5 million miles (4 million kilometers) from Pluto.

Three billion miles from Earth and just two and a half million miles from Pluto, NASA’s New Horizons spacecraft has taken its best image of four dark spots that continue to captivate.

The spots appear on the side of Pluto that always faces its largest moon, Charon—the face that will be invisible to New Horizons when the spacecraft makes its close flyby the morning of July 14. New Horizons principal investigator Alan Stern of the Southwest Research Institute, Boulder, Colorado, describes this image as “the last, best look that anyone will have of Pluto’s far side for decades to come.”

The spots are connected to a dark belt that circles Pluto’s equatorial region. What continues to pique the interest of scientists is their similar size and even spacing. “It’s weird that they’re spaced so regularly,” says New Horizons program scientist Curt Niebur at NASA Headquarters in Washington.  Jeff Moore of NASA’s Ames Research Center, Mountain View, California, is equally intrigued. “We can’t tell whether they’re plateaus or plains, or whether they’re brightness variations on a completely smooth surface.”

The large dark areas are now estimated to be 300 miles (480 kilometers) across, an area roughly the size of the state of Missouri.  In comparison with earlier images, we now see that the dark areas are more complex than they initially appeared, while the boundaries between the dark and bright terrains are irregular and sharply defined. 

In addition to solving the mystery of the spots, the New Horizons Geology, Geophysics and Imaging team is interested in identifying other surface features such as impact craters, formed when smaller objects struck the dwarf planet. Moore notes, “When we combine images like this of the far side with composition and color data the spacecraft has already acquired but not yet sent to Earth, we expect to be able to read the history of this face of Pluto.”

When New Horizons makes its closest approach to Pluto in just three days, it will focus on the opposing or “encounter hemisphere” of the dwarf planet. On the morning of July 14, New Horizons will pass about 7,800 miles (12,500 kilometers) from the face with a large heart-shaped feature that’s captured the imagination of people around the world.

New Image of Pluto: 'Houston, We Have Geology'


Image above: An annotated version indicates features described in the text, and includes a reference globe showing Pluto’s orientation in the image, with the equator and central meridian in bold.

It began as a point of light. Then, it evolved into a fuzzy orb. Now – in its latest portrait from NASA’s New Horizons spacecraft – Pluto is being revealed as an intriguing new world with distinct surface features, including an immense dark band known as the “whale.”

As the newest black and white image from New Horizons’ Long Range Reconnaissance Imager (LORRI) appeared on the morning of July 10, members of the science team reacted with joy and delight, seeing Pluto as never before. There will no doubt be many similar moments to come. New images and data are being gathered each day as New Horizons speeds closer to a July 14 flyby of Pluto, following a journey of three billion miles.


Image above: Science team members react to the latest image of Pluto at the Johns Hopkins University Applied Physics Lab on July 10, 2015. Left to right: Cathy Olkin, Jason Cook, Alan Stern, Will Grundy, Casey Lisse, and Carly Howett.

“We’re close enough now that we’re just starting to see Pluto’s geology,” said New Horizons program scientist Curt Niebur, NASA Headquarters in Washington, who’s keenly interested in the gray area just above the whale’s “tail” feature. “It’s a unique transition region with a lot of dynamic processes interacting, which makes it of particular scientific interest.”

New Horizons’ latest image of Pluto was taken on July 9, 2015 from 3.3 million miles (5.4 million kilometers) away, with a resolution of 17 miles (27 kilometers) per pixel. At this range, Pluto is beginning to reveal the first signs of discrete geologic features. This image views the side of Pluto that always faces its largest moon, Charon, and includes the so-called “tail” of the dark whale-shaped feature along its equator. (The immense, bright feature shaped like a heart had rotated from view when this image was captured.)

“Among the structures tentatively identified in this new image are what appear to be polygonal features; a complex band of terrain stretching east-northeast across the planet, approximately 1,000 miles long; and a complex region where bright terrains meet the dark terrains of the whale,” said New Horizons principal investigator Alan Stern. “After nine and a half years in flight, Pluto is well worth the wait.”

Pluto By Moonlight

It’s Antarctic winter on Pluto. The sun has not been visible for twenty years in this frigid south polar region; it will not shine again for another 80 years. The only source of natural light is starlight and moonlight from Pluto’s largest moon, Charon.

On July 14, New Horizons mission scientists will soon obtain the first images of the night region of Pluto, using only the light from Charon, itself softly illuminated by a Sun 1,000 times dimmer than it is at Earth. The images will provide New Horizons’ only view of Pluto’s lesser-known south polar region, currently in the midst of a numbingly-long winter. The pictures will be made with the LORRI and Ralph instruments, shortly after New Horizons passes its point of closest approach to Pluto.


Image caption: In this artist's rendering, Pluto's largest moon Charon rises over the frozen south pole surface of Pluto, casting a faint silvery luminescence across the distant planetary landscape.

If you stood on the night region of Pluto at that moment of closest approach by New Horizons – looking up at a distinctly gray Charon - it would appear seven times larger in the sky than Earth’s moon. Charon, although three billion miles from the sun, is so close to Pluto and so ice-covered that it would be only five times dimmer than the full moon seen from Earth. At your feet, the icy surface – resembling a sooty snow bank - would be bathed in Charon’s faint glow. The area around you would be dim, but not so dark that you would bump into things.

On your moonlight stroll on Pluto you’d notice that your shadow, cast by Charon, is much less defined than your shadow from moonlight on Earth. A wisp of cloud might even pass in front of Charon as you look up.

If you stood on Pluto’s Charon-facing side as New Horizons speeds by, you would see Charon go through a cycle of phases during a “Pluto Day” - 6 days and 10 hours—but not the complete set of phases our moon displays to us on Earth. Seen from Pluto during that time, Charon would go from a wide crescent, to a “quarter moon,” then to gibbous (partway between quarter and full phases), and back again.

New Horizons has been traveling for nine-and-a-half-years to bring humankind its first exploration of the Pluto system. While the sunlit features of Pluto are growing sharper every day, the shadowy winter region is still cloaked in mystery—but not for long.

“The only way for New Horizons to observe Pluto’s elusive night region is to see it in ‘Charonshine,’” says Cathy Olkin, New Horizons deputy project scientist. “It’s almost time for the big reveal, and I couldn’t be more excited.”

The Johns Hopkins University Applied Physics Laboratory in Laurel, Maryland, designed, built, and operates the New Horizons spacecraft, and manages the mission for NASA's Science Mission Directorate. The Southwest Research Institute, based in San Antonio, leads the science team, payload operations and encounter science planning. New Horizons is part of the New Frontiers Program managed by NASA's Marshall Space Flight Center in Huntsville, Alabama.

Artist's view of New Horizons spacecraft passing over Pluto

At 7:49 AM EDT on Tuesday, July 14 New Horizons will zip past Pluto at 30,800 miles per hour (49,600 kilometers per hour), with a suite of seven science instruments busily gathering data. The mission will complete the initial reconnaissance of the solar system with the first-ever look at the icy dwarf planet.

http://www.nasa.gov/multimedia/nasatv/index.html

Follow the path of the spacecraft in coming days in real time with a visualization of the actual trajectory data, using NASA’s online Eyes on Pluto: http://eyes.jpl.nasa.gov/eyes-on-pluto.html

Stay in touch with the New Horizons mission with #PlutoFlyby and on Facebook at: https://www.facebook.com/new.horizons1

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

Images, Text, Credits: NASA/JHUAPL/SWRI/Michael Soluri/Tricia Talbert.

Best regards, Orbiter.ch

A battery problem grounded in Hawaii Solar Impulse 2











SolarImpulse- Around The World patch.

July 11, 2015

The solar plane can not take back his world tour for at least two to three weeks, due to overheating of the batteries during his crossing of the Pacific.


Image Above: Solar Impulse landing in Hawaii. Solar Impulse 2 remain grounded in Hawaii for at least two to three weeks. Reason: overheating of the batteries during his crossing of the Pacific.

Repairs on Solar Impulse 2 is necessary, the organization said in a statement Saturday. The batteries were partially damaged irreversibly and replacement of defective parts could take several weeks.

Overheating occurs during the first ascent from Nagoya toward Hawaii in early oceanic flight record five days and five nights. Excess insulation is concerned, and the temperature could not be lowered for the remainder of the flight.

video
Solar Impulse Airplane: Landing in Hawaii

The team is studying different options to solve this problem, but no flights will be possible within two to three weeks, the statement said.

Departure from Abu Dhabi on March 9, Solar Impulse 2 has accomplished so far almost 18,000 kilometers. It landed on July 3 on the island of Oahu, Hawaii, after a Pacific crossing from Japan of 8,200 km. This stage was the longest of the world tour scheduled on 35,000 kilometers.

Still a chance to complete in 2015

The next destination was Phoenix, Arizona. Follow the crossing of the United States to the east coast.

Solar Impulse 2 landing in Hawaii, André Borschberg the pilot

This new setback, while the solar plane had already had to wait a month in China, reduces the chances of complete round the world in 2015. The deadline for the crossing of the Atlantic was set for mid-August, requires sunshine.

"But we still have a chance," said the ats spokeswoman Alexandra Gindroz. The crossing of the United States can be done in 48 hours, it can go very fast, she says. Otherwise, if Hawaii repairs were taking too much time, the epic would continue in 2016, as has already been suggested both pilots.

For more information about SolarImpulse Around The World, visit: http://www.solarimpulse.com/

Images, Video, Text, Credits: SolarImpulse/ATS/Orbiter.ch Aerospace.

Greetings, Orbiter.ch

vendredi 10 juillet 2015

PSLV C28 successfully launches five UK Satellites











ISRO - Indian Space Research Organisation logo.


Jul 10, 2015

The Indian Space Research Organisation (ISRO) Polar Satellite Launch Vehicle (PSLV) conducted its thirtieth flight on Friday evening local time, deploying five British satellites into a Sun-Synchronous orbit. Liftoff occurred at 21:58 local time (16:28 UTC) from the First Launch Pad at the Satish Dhawan Space Centre.

PSLV C-28 lifts off with five British satellites

The Polar Satellite Launch Vehicle (PSLV), in its thirtieth flight (PSLV-C28), launched three identical DMC3 optical earth observation satellites built by Surrey Satellite Technology Limited (SSTL), United Kingdom (UK). The three DMC3 satellites, each weighing 447 kg, launched into a 647 km Sun-Synchronous Orbit (SSO) using the high-end version of PSLV (PSLV-XL) from Satish Dhawan Space Centre, Sriharikota (SDSC-SHAR), the spaceport of India. PSLV-C28 will be the ninth flight of PSLV in ‘XL’ configuration.

The PSLV-C28, in addition to the three DMC3 satellites, also carried two auxiliary satellites from UK, viz., CBNT-1, a technology demonstrator earth observation micro satellite built by SSTL, and De-OrbitSail, a technology demonstrator nano satellite built by Surrey Space Centre.

With the overall lift-off mass of the five satellites amounting to about 1440 kg, this mission becomes the heaviest commercial mission undertaken by Antrix/ISRO till date.

video
 PSLV-C28 / DMC3 Launch - Rocket Successfully Launches 5 British Satellites

Accommodating the three DMC3 satellites each with a height of about 3 meter within the existing payload fairing of PSLV, was a challenge. To mount these satellites onto the launcher, a circular Launcher adaptor called as L-adaptor and a triangular deck called Multiple Satellite Adapter-Version 2 (MSA-V2), were newly designed and realized by ISRO for this specific purpose.

These international customer satellites have been launched as part of the arrangement entered into between DMC International Imaging (DMCii), a wholly owned subsidiary of SSTL, UK; and Antrix Corporation Limited (Antrix), the commercial arm of Indian Space Research Organisation (ISRO), a Government of India Company under Department of Space.

DMC3

The DMC3 constellation, comprising of three advanced mini-satellites DMC3-1, DMC3-2 and DMC3-3, is designed to address the need for simultaneous high spatial resolution and high temporal resolution optical Earth Observation. Launched into a single Low-Earth Orbit plane and phased with a separation of 120° between them, these satellites can image any target on the Earth’s surface every day. Major application areas include surveying the resources on earth and its environment, managing urban infrastructure and monitoring of disasters.


CBNT-1, weighing 91 kg, is an optical Earth Observation technology demonstration micro satellite built by SSTL. The 7 kg De-orbitSail from Surrey Space Centre, is an experimental nano satellite for demonstration of large thin membrane sail and drag deorbiting using this sail.

For more information about Indian Space Research Organisation (ISRO), visit: http://www.isro.gov.in/

Images, Video, Text, Credits: ISRO/Orbiter.ch Aerospace.

Best regards, Orbiter.ch

Curiosity Mars Rover Tracks Sunspots












NASA - Mars Science Laboratory (MSL) patch.

July 10, 2015

Fast Facts:

- Some sunspots are large enough to be visible in images from Curiosity's Mast Camera

- Information about sunspots on the side of the sun facing away from Earth is helpful for space weather forecasting

- Curiosity is investigating rocks near 'Marias Pass' and preparing for a drill test


Animations above: The sequence of seven images in this animation shows sunspots as viewed by NASA's Curiosity Mars rover from June 27 to July 8, 2015. Animations credits: NASA/JPL-Caltech/MSSS/Texas A&M University.

While busily investigating bedrock types on Mars' Mount Sharp and preparing for a drill test, NASA's Curiosity Mars rover has also been looking up frequently to monitor sunspots on the face of the sun that is turned away from Earth.

Large sunspots are evident in views from Curiosity's Mast Camera (Mastcam). Scientists temporarily have no other resource providing views of the sun from the opposite side of the solar system from Earth. The sun completes a rotation about once a month -- faster near its equator than near its poles. Information about sunspots that develop before they rotate into view of Earth and Earth-orbiting spacecraft is helpful in predicting space-weather effects of solar emissions related to sunspots.

Mars Rover Curiosity. Image Credit: NASA

A series of images from Curiosity showing sunspots rotating eastward in late June and early July is online at:

http://www.jpl.nasa.gov/spaceimages/details.php?id=PIA19801

One sunspot or cluster that rotated out of Curiosity's view over the July 4 weekend showed up by July 7 as a source area of a solar eruption observed by NASA's Earth-orbiting Solar Dynamics Observatory, as seen at:

http://www.jpl.nasa.gov/spaceimages/details.php?id=PIA19680

Another sunspot being tracked by Curiosity is on pace to face Earthward next week.

NASA's STEREO-A spacecraft, which monitors the sun, is currently almost exactly behind the sun from Earth's perspective, but for precisely that reason it is temporarily out of communication. The sun disrupts radio transmissions that pass too close to it. Communication with Curiosity was also suspended last month when Mars passed nearly behind the sun, but the rover resumed full communication and operations in late June. Daily information from STEREO-A is expected to begin again this month.


Image above: An eruption from the surface of the sun is conspicuous in the lower left portion of this July 6, 2015, image from NASA's Earth-orbiting Solar Dynamics Observatory. Image credit: NASA.

"Tracking the sunspot activity on the far side of the sun is useful for space-weather forecasting," said Yihua Zheng, project leader for NASA Space Weather Services at NASA Goddard Space Flight Center, Greenbelt, Maryland. "It helps us monitor how the sunspots evolve and grow before they become visible from this side."

Space weather forecasting aids in anticipating and taking precautions against possible effects of solar storms on spacecraft orbiting Earth and elsewhere in the solar system. Intense space weather can degrade telephone communications, broadcasting and other electronic technology on Earth.

The main purpose for most imaging of the sun by Curiosity and other Mars rovers has been to monitor how its apparent brightness is affected by dust in Mars' atmosphere above the rovers. Mark Lemmon of Texas A&M University, College Station, is a Mastcam team member who studies the Martian atmosphere. Three months ago, he coordinated sunset imaging by Curiosity for a Martian evening when Mercury was passing directly in front of the sun from Mars' viewpoint.


Animations above: The sequence of six images in this animation shows sunspots as viewed by NASA's Curiosity Mars rover from April 4 to April 15, 2015. Animations credits: NASA/JPL-Caltech/MSSS/Texas A&M University.

"We saw sunspots in the images during the Mercury transit, and I was trying to distinguish Mercury from a sunspot," Lemmon said. "I checked with heliophysicists who study sunspots and learned that STEREO-A was out of communications, so there was no current information about sunspots on that side of the sun. That's how we learned it would be useful for Curiosity to monitor sunspots."

In addition to its sunspot viewing, Curiosity is examining rocks near "Marias Pass." A test is planned this month for the percussion mechanism of the rover's sample-collecting drill, which exhibited a transient short circuit during transfer of sample material collected four months ago. The test is designed to provide diagnostic information for use in planning the rover's next drilling operation, possibly in the Marias Pass area.

Curiosity has been working on Mars since early August 2012. It reached the base of Mount Sharp last year after fruitfully investigating outcrops closer to its landing site and then trekking to the mountain. The main mission objective now is to examine successively higher layers of Mount Sharp.

JPL, a division of the California Institute of Technology in Pasadena, built the rover and manages the project for NASA's Science Mission Directorate in Washington. For more information about Curiosity, visit: http://www.nasa.gov/msl and http://mars.jpl.nasa.gov/msl

You can follow the mission on Facebook and Twitter at: http://www.facebook.com/marscuriosity and http://www.twitter.com/marscuriosity

Images (mentioned), Animations (mentioned), Text, Credits: NASA/Dwayne Brown/JPL/Guy Webster/GSFC/Karen Fox.

Best regards, Orbiter.ch

Hubble Looks at Stunning Spiral











NASA - Hubble Space Telescope patch.

July 10, 2015


This little-known galaxy, officially named J04542829-6625280, but most often referred to as LEDA 89996, is a classic example of a spiral galaxy. The galaxy is much like our own galaxy, the Milky Way. The disk-shaped galaxy is seen face on, revealing the winding structure of the spiral arms. Dark patches in these spiral arms are in fact dust and gas — the raw materials for new stars. The many young stars that form in these regions make the spiral arms appear bright and bluish.

The galaxy sits in a vibrant area of the night sky within the constellation of Dorado (The Swordfish), and appears very close to the Large Magellanic Cloud  — one of the satellite galaxies of the Milky Way.

The observations were carried out with the high resolution channel of Hubble’s Advanced Camera for Surveys.

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

Related links:

Hubble Space Telescope: http://www.nasa.gov/mission_pages/hubble/main/index.html

Hubble websites: http://www.spacetelescope.org/ and http://hubblesite.org/

Image credit: ESA/Hubble & NASA, Acknowledgement: Flickr user C. Claude/Text credit: European Space Agency (ESA).

Greetings, Orbiter.ch

jeudi 9 juillet 2015

LHC back in collision mode












CERN - European Organization for Nuclear Research logo.

July 9, 2015


Image above: Tuesday, 7 July: a proton-proton collision leaves multiple tracks in the different layers of the CMS detector. (Image: CMS).

All systems are go once again for physics at the Large Hadron Collider (LHC). On Saturday evening proton collisions resumed at the world’s most powerful accelerator and the experiments began collecting data once more. At present, 152 bunches of protons are circulating in each direction in the 27 kilometre machine, but the goal is to increase the number of protons over the next two weeks to close to 1000 bunches per beam.


Image above: An image of a proton-proton collision taken in the ALICE detector on Sunday 5 July. (Image: ALICE).

For several days, the LHC had temporarily halted data collection to “chase” electron clouds out of its beam pipes. These electrons, generated in cascades, destabilise the beam and compromise the operation of the accelerator at high intensity, i.e. at more than 1000 bunches per beam. The cleaning operation was successful, since the operators succeeded in circulating up to 1200 proton bunches in each beam at the LHC’s injection energy, 450 gigaelectronvolts (GeV). This phase allowed the electron clouds to be dissipated and the beam stability to be improved. Since Friday, the LHC has been back in operation at its nominal collision energy of 13 teraelectronvolts (TeV). The operators can now increase the number of bunches circulating in the machine, spaced apart by 50 nanoseconds.


Image above: An image of a proton-proton collision taken in the LHCb detector on Tuesday 7 July. (Image: LHCb).

The LHC experiments will continue to collect data until the end of July. A new cleaning phase is then scheduled to allow the beam intensity to be increased even further by reducing the amount of space between the bunches by 50%.

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:

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

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

Images (mentioned), Text, Credits: CERN/Corinne Pralavorio.

Greetings, Orbiter.ch

Distant Black Hole Wave Twists Like Giant Whip












NRAO - National Radio Astronomy Observatory logo.

July 9, 2015


Image above: This cartoon shows how magnetic waves, called Alfven S-waves, propagate outward from the base of black hole jets. The jet is a flow of charged particles, called a plasma, which is launched by a black hole. The jet has a helical magnetic field (yellow coil) permeating the plasma. The waves then travel along the jet, in the direction of the plasma flow, but at a velocity determined by both the jet¹s magnetic properties and the plasma flow speed. The BL Lac jet examined in a new study is several light-years long, and the wave speed is about 98 percent the speed of light. Image Credits: Caltech.

Fast-moving magnetic waves emanating from a distant supermassive black hole undulate like a whip whose handle is being shaken by a giant hand, according to a new study using data from the National Radio Astronomy Observatory’s Very Long Baseline Array. Scientists used this instrument to explore the galaxy/black hole system known as BL Lacertae (BL Lac) in high resolution.

"The waves are excited by a shaking motion of the jet at its base," said David Meier, a now-retired astrophysicist from NASA's Jet Propulsion Laboratory and the California Institute of Technology, both in Pasadena.

The team's findings, detailed in the April 10 issue of The Astrophysical Journal, mark the first time so-called Alfvén (pronounced Alf-vain) waves have been identified in a black hole system.

Alfvén waves are generated when magnetic field lines, such as those coming from the sun or a disk around a black hole, interact with charged particles, or ions, and become twisted or coiled into a helical shape. In the case of BL Lac, the ions are in the form of particle jets that are flung from opposite sides of the black hole at near light speed.


Image above: This artist's concept illustrates a supermassive black hole with millions to billions times the mass of our sun. Image Credits: NASA/JPL-Caltech.

"Imagine running a water hose through a slinky that has been stretched taut," said first author Marshall Cohen, an astronomer at Caltech. “A sideways disturbance at one end of the slinky will create a wave that travels to the other end, and if the slinky sways to and fro, the hose running through its center has no choice but to move with it."

A similar thing is happening in BL Lac, Cohen said. The Alfvén waves are analogous to the propagating sideways motions of the slinky, and as the waves propagate along the magnetic field lines, they can cause the field lines -- and the particle jets encompassed by the field lines -- to move as well.

It’s common for black hole particle jets to bend -- and some even swing back and forth. But those movements typically take place on timescales of thousands or millions of years. "What we see is happening on a timescale of weeks," Cohen said. "We're taking pictures once a month, and the position of the waves is different each month."

"By analyzing these waves, we are able to determine the internal properties of the jet, and this will help us ultimately understand how jets are produced by black holes," said Meier.

VLBA Antenna at Owens Valley. Image Credit: NRAO

Interestingly, from the vantage of astronomers on Earth, the Alfvén waves emanating from BL Lac appear to be traveling about five times faster than the speed of light, but it's only an optical illusion. The illusion is difficult to visualize but has to do with the fact that the waves are traveling slightly off our line of sight at nearly the speed of light. At these high speeds, time slows down, which can throw off the perception of how fast the waves are actually moving.

Other Caltech authors on the paper include Talvikki Hovatta, a former Caltech postdoctoral scholar. Scientists from the University of Cologne and the Max Planck Institute for Radioastronomy in Germany; the Isaac Newton Institute of Chile; Aalto University in Finland; the Astro Space Center of Lebedev Physical Institute, the Pulkovo Observatory, and the Crimean Astrophysical Observatory in Russia; Purdue University in Indiana and Denison University in Granville, Ohio.

Related link:

Very Long Baseline Array - National Radio Astronomy Observatory: https://science.nrao.edu/facilities/vlba

VLA and the VLBA - National Radio Astronomy Observatory: http://www.aoc.nrao.edu/intro/NM_astro.html

Caltech manages JPL for NASA.

NASA/JPL/Whitney Clavin/Tony Greicius.

Pluto and Charon: New Horizons’ Dynamic Duo












NASA - New Horizons Mission logo.

July 9, 2015


Image above: New Horizons was about 3.7 million miles (6 million kilometers) from Pluto and Charon when it snapped this portrait late on July 8, 2015. Most of the bright features around Pluto’s edge are a result of image processing, but the bright sliver below the dark “whale,” which is also visible in unprocessed images, is real. Image Credits: NASA-JHUAPL-SWRI.


Image above: This is the same image of Pluto and Charon from July 8, 2015; color information obtained earlier in the mission from the Ralph instrument has been added. Image Credits: NASA-JHUAPL-SWRI.


Image above: Image of Pluto only from the New Horizons’ Long Range Reconnaissance Imager (LORRI), July 8, 2015. Most of the bright features around Pluto’s edge are a result of image processing, but the bright sliver below the dark “whale,” which is also visible in unprocessed images, is real. Image Credits: NASA-JHUAPL-SWRI.


Image above: Image of Charon only from the New Horizons’ Long Range Reconnaissance Imager (LORRI), July 8, 2015. Image Credits: NASA-JHUAPL-SWRI.

They’re a fascinating pair: Two icy worlds, spinning around their common center of gravity like a pair of figure skaters clasping hands. Scientists believe they were shaped by a cosmic collision billions of years ago, and yet, in many ways, they seem more like strangers than siblings.

A high-contrast array of bright and dark features covers Pluto’s surface, while on Charon, only a dark polar region interrupts a generally more uniform light gray terrain. The reddish materials that color Pluto are absent on Charon. Pluto has a significant atmosphere; Charon does not. On Pluto, exotic ices like frozen nitrogen, methane, and carbon monoxide have been found, while Charon’s surface is made of frozen water and ammonia compounds. The interior of Pluto is mostly rock, while Charon contains equal measures of rock and water ice.

“These two objects have been together for billions of years, in the same orbit, but they are totally different,” said Principal Investigator Alan Stern of the Southwest Research Institute (SwRI), Boulder, Colorado

New Horizons spacecraft orbiting Pluto. Image Credits: NASA

Charon is about 750 miles (1200 kilometers) across, about half the diameter of Pluto—making it the solar system’s largest moon relative to its planet. Its smaller size and lower surface contrast have made it harder for New Horizons to capture its surface features from afar, but the latest, closer images of Charon’s surface show intriguing fine details.

Newly revealed are brighter areas on Charon that members of the mission’s Geology, Geophysics and Imaging team (GGI) suspect might be impact craters. If so, the scientists would put them to good use. “If we see impact craters on Charon, it will help us see what’s hidden beneath the surface,” said GGI leader Jeff Moore of NASA’s Ames Research Center. “Large craters can excavate material from several miles down and reveal the composition of the interior.”

In short, said GGI deputy team leader John Spencer of SwRI, “Charon is now emerging as its own world. Its personality is beginning to really reveal itself.”

video
 NASA's New Horizons spacecraft arrives at Pluto on July 14th

Video above: NASA's New Horizons spacecraft arrives at Pluto on July 14th; a journey lasting nearly 10 years and traveling over 3 billion miles. Watch coverage of the historic flyby of Pluto on NASA Television as NASA counts down to the Pluto encounter of a lifetime.
http://www.nasa.gov/multimedia/nasatv/index.html

The Johns Hopkins University Applied Physics Laboratory in Laurel, Maryland, designed, built, and operates the New Horizons spacecraft, and manages the mission for NASA's Science Mission Directorate. The Southwest Research Institute, based in San Antonio, leads the science team, payload operations and encounter science planning. New Horizons is part of the New Frontiers Program managed by NASA's Marshall Space Flight Center in Huntsville, Alabama.

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

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

Greetings, Orbiter.ch

NASA's Swift Reveals a Black Hole Bull's-eye












NASA - Swift Mission patch.

July 9, 2015

What looks like a shooting target is actually an image of nested rings of X-ray light centered on an erupting black hole. On June 15, NASA's Swift satellite detected the start of a new outburst from V404 Cygni, where a black hole and a sun-like star orbit each other. Since then, astronomers around the world have been monitoring the ongoing light show. 

On June 30, a team led by Andrew Beardmore at the University of Leicester, U.K., imaged the system using the X-ray Telescope aboard Swift, revealing a series concentric rings extending about one-third the apparent size of a full moon. A movie made by combining additional observations acquired on July 2 and 4 shows the expansion and gradual fading of the rings.


Animation above: Rings of X-ray light centered on V404 Cygni, a binary system containing an erupting black hole (dot at center), were imaged by the X-ray Telescope aboard NASA's Swift satellite from June 30 to July 4. A narrow gap splits the middle ring in two. Color indicates the energy of the X-rays, with red representing the lowest (800 to 1,500 electron volts, eV), green for medium (1,500 to 2,500 eV), and the most energetic (2,500 to 5,000 eV) shown in blue. For comparison, visible light has energies ranging from about 2 to 3 eV. The dark lines running diagonally through the image are artifacts of the imaging system. Animation Credits: Andrew Beardmore (Univ. of Leicester) and NASA/Swift.

Astronomers say the rings result from an "echo" of X-ray light. The black hole's flares emit X-rays in all directions. Dust layers reflect some of these X-rays back to us, but the light travels a longer distance and reaches us slightly later than light traveling a more direct path. The time delay creates the light echo, forming rings that expand with time.  

Detailed analysis of the expanding rings shows that they all originate from a large flare that occurred on June 26 at 1:40 p.m. EDT. There are multiple rings because there are multiple reflecting dust layers between 4,000 and 7,000 light-years away from us. Regular monitoring of the rings and how they change as the eruption continues will allow astronomers to better understand their nature.

"The flexible planning of Swift observations has given us the best dust-scattered X-ray ring images ever seen," Beardmore said. "With these observations we can make a detailed study of the normally invisible interstellar dust in the direction of this black hole."


Images above: The Swift X-ray image of V404 Cygni covers a patch of the sky equal to about half the apparent diameter of the full moon. This image shows the rings as they appeared on June 30. Images Credits: NASA's Scientific Visualization Studio (left), Andrew Beardmore (Univ. of Leicester); NASA/Swift (right).

V404 Cygni is located about 8,000 light-years away. Every couple of decades the black hole fires up in an outburst of high-energy light. Its previous eruption ended in 1989.

The investigating team includes scientists from the Universities of Leicester, Southampton, and Oxford in the U.K., the University of Alberta in Canada, and the European Space Agency in Spain.

Swift was launched in November 2004 and is managed by NASA's Goddard Space Flight Center in Greenbelt, Maryland. Goddard operates the spacecraft in collaboration with Penn State University in University Park, Pennsylvania, the Los Alamos National Laboratory in New Mexico and Orbital Sciences Corp. in Dulles, Virginia. International collaborators are located in the United Kingdom and Italy. The mission includes contributions from Germany and Japan.

Related Link:

Astronomers use cosmic gravity to create a ‘black-hole-scope’: http://orbiterchspacenews.blogspot.ch/2015/07/astronomers-use-cosmic-gravity-to.html

NASA Missions Monitor a Waking Black Hole: http://orbiterchspacenews.blogspot.ch/2015/06/nasa-missions-monitor-waking-black-hole.html

Monster black hole wakes up after 26 years: http://orbiterchspacenews.blogspot.ch/2015/06/monster-black-hole-wakes-up-after-26.html

NASA’s Chandra Captures X-Ray Echoes Pinpointing Distant Neutron Star: http://orbiterchspacenews.blogspot.ch/search?q=Chandra+Captures+X-Ray+Echoes+Pinpointing+Distant+Neutron+Star

For more information about Swift mission, visit: http://www.nasa.gov/mission_pages/swift/main/index.html

Animation (mentioned), Image (mentioned), Text, Credits: NASA's Goddard Space Flight Center/Francis Reddy/Rob Garner.

Cheers, Orbiter.ch

Huge New Survey to Shine Light on Dark Matter












ESO - European Southern Observatory logo.

9 July 2015

First results from VST KiDS Survey

The first results have been released from a major new dark matter survey of the southern skies using ESO’s VLT Survey Telescope (VST) at the Paranal Observatory in Chile. The VST KiDS survey will allow astronomers to make precise measurements of dark matter, the structure of galaxy halos, and the evolution of galaxies and clusters. The first KiDS results show how the characteristics of the observed galaxies are determined by the invisible vast clumps of dark matter surrounding them.

First Results from the KiDS Survey (montage)

Around 85% of the matter in the Universe is dark [1], and of a type not understood by physicists. Although it doesn’t shine or absorb light, astronomers can detect this dark matter through its effect on stars and galaxies, specifically from its gravitational pull. A major project using ESO’s powerful survey telescopes is now showing more clearly than ever before the relationships between this mysterious dark matter and the shining galaxies that we can observe directly [2].

The project, known as the Kilo-Degree Survey (KiDS), uses imaging from the VLT Survey Telescope and its huge camera, OmegaCAM. Sited at ESO’s Paranal Observatory in Chile, this telescope is dedicated to surveying the night sky in visible light — and it is complemented by the infrared survey telescope VISTA. One of the major goals of the VST is to map out dark matter and to use these maps to understand the mysterious dark energy that is causing our Universe's expansion to accelerate.

First Results from the KiDS Survey (visible light)

The best way to work out where the dark matter lies is through gravitational lensing — the distortion of the Universe's fabric by gravity, which deflects the light coming from distant galaxies far beyond the dark matter. By studying this effect it is possible to map out the places where gravity is strongest, and hence where the matter, including dark matter, resides.

As part of the first cache of papers, the international KiDS team of researchers, led by Koen Kuijken at the Leiden Observatory in the Netherlands [3], has used this approach to analyse images of over two million galaxies, typically 5.5 billion light-years away [4]. They studied the distortion of light emitted from these galaxies, which bends as it passes massive clumps of dark matter during its journey to Earth.

The first results come from only 7% of the final survey area and concentrate on mapping the distribution of dark matter in groups of galaxies. Most galaxies live in groups — including our own Milky Way, which is part of the Local Group — and understanding how much dark matter they contain is a key test of the whole theory of how galaxies form in the cosmic web. From the gravitational lensing effect, these groups turn out to contain around 30 times more dark than visible matter.

First Results from the KiDS Survey (dark matter)

"Interestingly, the brightest galaxy nearly always sits in the middle of the dark matter clump," says Massimo Viola (Leiden Observatory, the Netherlands) lead author of one of the first KiDS papers.

"This prediction of galaxy formation theory, in which galaxies continue to be sucked into groups and pile up in the centre, has never been demonstrated so clearly before by observations," adds Koen Kuijken.

The findings are just the start of a major programme to exploit the immense datasets coming from the survey telescopes and the data are now being made available to scientists worldwide through the ESO archive.

The KiDS survey will help to further expand our understanding of dark matter. Being able to explain dark matter and its effects would represent a major breakthrough in physics.

Notes:

[1] Astronomers have found that the total mass/energy content of the Universe is split in the proportions 68% dark energy, 27% dark matter and 5% “normal” matter. So the 85% figure relates to the fraction of “matter” that is dark.

[2] Supercomputer calculations show how a Universe filled with dark matter will evolve: over time dark matter will clump into a huge cosmic web structure, and galaxies and stars form where gas is sucked into the densest concentrations of dark matter.

[3] The international KiDS team of researchers includes scientists from the Netherlands, the UK, Germany,  Italy and Canada.

[4] This work made use of the 3D map of galaxy groups, provided by the Galaxy And Mass Assembly project (GAMA), following extensive observations on the Anglo-Australian Telescope.

More information:

This research was presented in a series of papers submitted to several leading journals. A list can be found here.

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”.

Links:

Links to research papers: http://kids.strw.leidenuniv.nl/papers.php

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

Related links:

Kilo-Degree Survey (KiDS): http://kids.strw.leidenuniv.nl/

VLT Survey Telescope: https://www.eso.org/public/teles-instr/surveytelescopes/vst/

OmegaCAM: http://www.eso.org/public/teles-instr/surveytelescopes/vst/camera/

VISTA: http://www.eso.org/public/teles-instr/surveytelescopes/vista/

Images, Text, Credits: ESO/Kilo-Degree Survey Collaboration/A. Tudorica & C. Heymans.

Best regards, Orbiter.ch

A galaxy in bloom












ESA - Hubble Space Telescope logo.

9 July 2015

New Hubble snap of ESO 381-12

Hubble image of ESO 381-12

The ghostly shells of galaxy ESO 381-12 are captured here in a new image from the NASA/ESA Hubble Space Telescope, set against a backdrop of distant galaxies. The strikingly uneven structure and the clusters of stars that orbit around the galaxy suggest that ESO 381-12 may have been part of a dramatic collision sometime in its relatively recent past.

Located roughly 270 million light-years from Earth in the constellation of Centaurus (The Centaur), a bright constellation in the southern sky, ESO 381-12, also known as PGC 42871, is categorised as a lenticular galaxy — a hybrid galaxy type that shares properties with both spiral galaxies and elliptical galaxies.

The area around ESO 381-12 (ground-based image)

The delicate shells that bloom outwards from ESO 381-12 are very rarely found around this type of galaxy and their cause is a bit of a cosmic mystery. It is thought that PGC 42871 may have recently interacted with another galaxy, sending shock waves through its structure much like ripples in a pond. These galactic mergers are violent processes, smashing together material within the clashing galaxies and completely changing how they look and how they will evolve in the future. This violent event likely triggered a wave of star formation throughout the galaxy, leading to the creation of many hot young stars.

video
Zooming in on ESO 381-12

Astronomers have studied ESO 381-12 in detail because of its very unusual structure. It was one of a sample of galaxies explored by Hubble’s Advanced Camera for Surveys during a recent study of the properties of shell galaxies created in merger events a billion or so years ago.

video
Panning across ESO 381-12

The prominent galaxy at the right of the frame, known as ESO 381-13 or PGC 42877, is a different beast altogether and both active star formation and dust can be seen within it. However, ESO 381-13 and the shell galaxy are at very similar distances from Earth and, despite their differences, may well be interacting.

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/

Related link:

Hubble’s Advanced Camera for Surveys: https://www.spacetelescope.org/about/general/instruments/acs/

Images, Text, Credits: NASA, ESA, P. Goudfrooij (STScI)/Digitized Sky Survey 2 (Acknowledgement: Davide De Martin)/Videos: NASA, ESA, Digitized Sky Survey 2.

Greetings, Orbiter.ch

Cutting through martian history












ESA - Mars Express Mission patch.

9 July 2015

Ascuris Planum topography

This colourful image resembles an abstract watercolour, but it is in fact a colour-coded topographic map of one of the most geologically diverse regions on Mars.

The images featured in this release were taken by the high-resolution stereo camera on ESA’s Mars Express on 10 November 2014, and focus on Tempe Fossae in the Ascuris Planum region of Mars.

Situated at the northeastern edge of the Tharsis volcanic province, this region is found close to the transitional zone between the ancient southern highlands and the young northern lowlands. It is characterised by a large variety of tectonic and volcanic structures with ages that span much of the Red Planet’s geologic history.

Ascuris Planum context

As can also be seen in the colour image above, the region is criss-crossed by large numbers of linear and curvilinear features. These are most likely ‘graben’, products of the planet’s crust having been stretched apart. Graben is the term given to the section of the crust at lower elevation, bordered by sets of parallel faults.

The relative heights and depths of the graben can be seen in the colour-coded topography map, where red/white represents the highest terrain, and blues and purples show lower terrain. They are a few kilometres wide and 1–2 km deep.

Ascuris Planum

The anaglyph image below also gives a good impression of the topography of these features.

While the majority of the troughs making up Tempe Fossae seem to follow a parallel NE–SW orientation, the small section showcased in the images presented here also reveals another set of troughs running almost perpendicular to these. The cross-cutting nature of these features indicates different periods of stress and strain over the history of the planet.

Ascuris Planum 3D

In addition to the tectonic features, a number of lava flows can be spotted, notably towards the south at higher elevations. These may have erupted from fissures and are perhaps associated with the nearby small shield volcano Labeatis Mons.

On the right (northern) side of the main image, and in perspective view in the image below, an interesting impact crater can be seen with its rim breached by a graben. Remnants of the crater’s ejecta blanket – the debris that is thrown out during an impact – have also been truncated and can be seen on the opposite side of the graben.

A smaller crater to the far right of the perspective view also exhibits a breached rim.

Ascuris Planum perspective

Nearby, there are strings of circular pit craters. Three main processes are known to form such pit-crater chain structures, involving volcanism, tectonic activity or groundwater.

If volcanic, then they may point to ancient lava tubes. Over time, segments of their roofs collapse, leaving circular features on the surface. This is sometimes seen on the flanks of shield volcanoes – on Earth this is seen in Hawaii, for example.

Pit crater chains are also formed during extension of the crust, such as during the formation of graben. When the crust is stretched apart linear fractures are formed and the weakened material drops down into void spaces, creating the appearance of a pit-chain.

Mars Express

Alternatively, groundwater can generate sinkholes: underground caverns are created via percolating groundwater, dissolving material until the ceilings can no longer support the weight above, and it collapses in a string of pits.

Regardless of how the pits in the Ascuris Planum region of Mars formed, it is clear that this region has a complex past, with many episodes of geological activity.

Related links:

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

High Resolution Stereo Camera: http://berlinadmin.dlr.de/Missions/express/indexeng.shtml

Behind the lens...: http://www.esa.int/Our_Activities/Space_Science/Mars_Express/Behind_the_lens

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

ESA Planetary Science archive (PSA): http://www.rssd.esa.int/PSA

NASA Planetary Data System: http://pds-geosciences.wustl.edu/missions/mars_express/hrsc.htm

HRSC data viewer: http://hrscview.fu-berlin.de/

In depth:

Mars Express in depth: http://sci.esa.int/science-e/www/area/index.cfm?fareaid=9

Mars Express top 10 discoveries: http://sci.esa.int/jump.cfm?oid=51820

Images, Text, Credits: ESA/DLR/FU Berlin, CC BY-SA 3.0 IGO.

Best regards, Orbiter.ch