vendredi 27 avril 2012

CMS discovers new particle – Meet the Ξb*0 beauty baryon












CERN - European Organization for Nuclear Research logo.

April 27, 2012


Image above: The Ξb*0 particle shows a clear signal (blue) above the background level (red) (Image: CMS) The Compact Muon Solenoid (CMS) experiment at CERN has submitted a paper for publication describing the first observation of a new particle, an excited beauty baryon called the Ξb*0 (Ξb is pronounced "Csai - bee").

Baryons are subatomic particles whose mass is equal to or greater than that of a proton. The Standard Model of particle physics predicts the existence of Ξb baryons in charged, neutral or excited states. Though charged and neutral Ξb baryons have been seen in detectors before, this is the first time the an excited Ξb beauty baryon has been observed. CMS measured the mass of the new particle to be 5945.0 ± 2.8 MeV.

 LHC - CERN

CMS physicists found the Ξb*0 signal in a sample of about 530 trillion proton—proton collisions (an integrated luminosity of 5.3 inverse femtobarns) which were delivered by the Large Hadron Collider (LHC) operating at a centre-of-mass energy of 7 TeV in 2011.

The Ξb*0 adds to a growing list of discoveries at CERN in recent months. In December the ATLAS experiment announced the observation of a new "quarkonium state" containing a beauty quark bound with its antiquark, and in November the LHCb experiment reported a new effect in the decays of particles containing a charm quark (or antiquark).
With the LHC now running at 4TeV per beam, the collision number is set to increase, which enhances the machine's discovery potential considerably, and opens up new possibilities for searches for new and heavier particles.

Note:

1. CERN, the European Organization for Nuclear Research, is the world's leading laboratory for particle physics. It has its headquarters in Geneva. At present, its Member States are Austria, Belgium, Bulgaria, the Czech Republic, Denmark, Finland, France, Germany, Greece, Hungary, Italy, the Netherlands, Norway, Poland, Portugal, Slovakia, Spain, Sweden, Switzerland and the United Kingdom. Romania is a candidate for accession. Israel is an Associate Member in the pre-stage to Membership. India, Japan, the Russian Federation, the United States of America, Turkey, the European Commission and UNESCO have Observer status.

Find out more:
    CMS news: http://cms.web.cern.ch/news/observation-new-xib-beauty-particle
    The CMS experiment: http://cms.web.cern.ch/
    Quantum diaries: CMS observes a new beauty particle: http://www.quantumdiaries.org/2012/04/27/cms-observes-a-new-beauty-particle/
    ATLAS: http://atlas.ch/
    LHCb: http://lhcb-public.web.cern.ch/lhcb-public/

Image, Graphic, Text, Credit: CERN.

Greetings, Orbiter.ch

100 Days and Counting to NASA's Curiosity Mars Rover Landing










NASA Mars Science Laboratory (MSL) Mission patch.

 04.27.12

Mars Science Laboratory Spacecraft During Cruise, Artist's Concept

At 10:31 p.m. PDT today, April 27, (1:31 p.m. EDT), NASA's Mars Science Laboratory, carrying the one-ton Curiosity rover, will be within 100 days from its appointment with the Martian surface. At that moment, the mission has about 119 million miles (191 million kilometers) to go and is closing at a speed of 13,000 mph (21,000 kilometers per hour).

"Every day is one day closer to the most challenging part of this mission," said Pete Theisinger, Mars Science Laboratory project manager at NASA's Jet Propulsion Laboratory in Pasadena, Calif. "Landing an SUV-sized vehicle next to the side of a mountain 85 million miles from home is always stimulating. Our engineering and science teams continue their preparations for that big day and the surface operations to follow."

On Sunday, April 22, a week-long operational readiness test concluded at JPL. The test simulated aspects of the mission's early surface operations. Mission planners and engineers sent some of the same commands they will send to the real Curiosity rover on the surface of Mars to a test rover used at JPL.


Image above: Curiosity, the big rover of This artist's concept depicts the moment that NASA's Curiosity rover touches down onto the Martian surface. Image credit: NASA/JPL-Caltech.

"Our test rover has a central computer identical to Curiosity's currently on its way to Mars," said Eric Aguilar, the mission's engineering test lead at JPL. "We ran all our commands through it and watched to make sure it drove, took pictures and collected samples as expected by the mission planners. It was a great test and gave us a lot of confidence moving forward."

The Mars Science Laboratory spacecraft, launched Nov. 26, 2011, will deliver Curiosity to the surface of Mars on the evening of Aug. 5, 2012, PDT (early on Aug. 6, Universal Time and EDT) to begin a two-year prime mission. Curiosity's landing site is near the base of a mountain inside Gale Crater, near the Martian equator. Researchers plan to use Curiosity to study layers in the mountain that hold evidence about wet environments of early Mars.

video
The Cruise to Mars

JPL, a division of the California Institute of Technology in Pasadena, manages the mission for the NASA Science Mission Directorate, Washington. More information about Curiosity is online at http://www.nasa.gov/msl and http://mars.jpl.nasa.gov/msl/ .

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

Images, Text, Video, Credit: NASA / JPL / JPL-Caltech  / DC Agle / Guy Webster.

 Best regards, Orbiter.ch

Within the Realm of a Dying Star












NASA - Hubble Space Telescope patch.

April 27, 2012


The NASA/ESA Hubble Space Telescope has been on the forefront of research into the lives of stars like our sun. At the ends of their lives, these stars run out of nuclear fuel in a phase that is called the preplanetary or protoplanetary nebula stage. This Hubble image of the Egg Nebula shows one of the best views to date of this brief, but dramatic, phase in a star’s life.

During the preplanetary nebula phase, the hot remains of an aging star in the center of the nebula heat it up, excite the gas and make it glow over several thousand years. The short lifespan of preplanetary nebulae means there are relatively few of them in existence at any one time. Moreover, they are very dim, requiring powerful telescopes to be seen. This combination of rarity and faintness means they were only discovered comparatively recently. The Egg Nebula, the first to be discovered, was first spotted less than 40 years ago, and many aspects of this class of object remain shrouded in mystery.

At the center of this image, and hidden in a thick cloud of dust, is the nebula’s central star. While scientists can’t see the star directly, four searchlight beams of light coming from it shine out through the nebula. Researchers hypothesize that ring-shaped holes in the thick cocoon of dust, carved by jets coming from the star, let the beams of light emerge through the otherwise opaque cloud. The precise mechanism by which stellar jets produce these holes is not known, but one explanation is that a binary star system, rather than a single star, exists at the center of the nebula.

The onion-like layered structure of the more diffuse cloud surrounding the central cocoon is caused by periodic bursts of material being ejected from the dying star. The bursts typically occur every few hundred years.

This image is produced from exposures in visible and infrared light from Hubble’s Wide Field Camera 3.

 Hubble Space Telescope

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

For more information about Hubble visit: http://www.nasa.gov/hubble and http://hubblesite.org/

ESA Hubble site: http://www.spacetelescope.org/

Images, Text, Credit: ESA / Hubble, NASA.

Cheers, Orbiter.ch

Expedition 30 Lands in Kazakhstan














ISS - Expedition 30 Mission patch / ROSCOSMOS - Soyuz TMA-22 Mission patch.

April 27, 2012

The Soyuz TMA-22 spacecraft carrying Expedition 30 Commander Dan Burbank and Flight Engineers Anton Shkaplerov and Anatoly Ivanishin landed in Kazakhstan at 7:45 a.m. EDT. They undocked from the International Space Station at 4:18 a.m. officially ending their stay.

The Soyuz performed a deorbit burn at 6:49 a.m. before the descent module separated from the rest of the Russian spacecraft and entered the Earth’s atmosphere. Afterward, the Soyuz deployed several parachutes, slowing its descent, and then fired three small engines to soften its landing.


Image above: Expedition 30 Commander Dan Burbank is carried to a medical tent after being extracted from the Soyuz TMA-22 spacecraft he and Flight Engineers Anton Shkaplerov and Anatoly Ivanishin landed in. Credit: NASA TV.

video
Soyuz TMA-22 landing full

Read more about Soyuz landings: http://www.nasa.gov/mission_pages/station/structure/elements/soyuz/landing.html

The Soyuz TMA-22 descent

Support personnel have extracted the Expedition 30 crew members from the Soyuz and they are now being monitored by flight surgeons.

Expedition 31 began when Burbank, Shkaplerov and Ivanishin undocked from the station. Commander Oleg Kononenko and Flight Engineers Don Pettit and Andre Kuipers will continue their stay aboard the orbital laboratory until July 1. Scheduled to join them in mid-May are Flight Engineers Gennady Padalka, Joe Acaba and Sergei Revin, who will launch and arrive in the Soyuz TMA-04M spacecraft.

Read more about Expedition 31: http://www.nasa.gov/mission_pages/station/expeditions/expedition31/index.html

The new crewmates are completing their mission training at the Gagarin Cosmonaut Training Center in Star City, Russia. They will launch from the Baikonur Cosmodrome in Kazakhstan on May 15, and plan to stay in space until Sept. 17.

Images, Video, Text, Credits: ROSCOSMOS / Roscosmos TV / NASA TV / NASA.

Greetings, Orbiter.ch

Soyuz TMA-22 in the free flight

ROSCOSMOS - Soyuz TMA-22 Mission patch.

27/04/2012

In accordance with the schedule of the flight the International Space Station today at 12:18 GMT performed undocking of manned spacecraft Soyuz TMA-22 with the International Space Station (on the modulus of the "Search").

The Soyuz will perform a deorbit burn before the descent module separates from the rest of the Russian spacecraft and enters the Earth’s atmosphere. Afterwards, the Soyuz will deploy several parachutes slowing its descent and then fire three small engines to soften its landing in the steppe of Kazakhstan.


Image above: Expedition 31 Commander Oleg Kononenko (left) and Expedition 30 Commander Dan Burbank prepare to close the hatches between the International Space Station and the Soyuz TMA-22 spacecraft. Credit: NASA.

A landing capsule with a crew consisting of commander Anton Shkaplerova (Roscosmos), Anatoly Ivanishin flight engineers (Roscosmos) and Daniel Burbank (NASA) is expected in 15 hours 45 minutes Moscow time 88 kilometers north-east of the town of Arkalyk in Kazakhstan.

video
Soyuz TMA-22 Undocking

After undock Soyuz TMA-22 from the Russian segment of ISS and prior to the arrival on board the next Expedition will continue to work on the orbiting crew consisting of Russian Federal Space Agency cosmonaut Oleg Kononenko, astronauts André Cowper (ESA) and Donald Pettit (NASA).

The new crewmates are completing their mission training at the Gagarin Cosmonaut Training Center in Star City, Russia. They will launch from the Baikonur Cosmodrome in Kazakhstan on May 15, and plan to stay in space until Sept. 17.

Original text in Russian: http://www.federalspace.ru/main.php?id=2&nid=19019

For more information about International Space Station (ISS), visit: http://www.nasa.gov/mission_pages/station/main/index.html

Press-service of Federal Space Agency and the PCO (Roscosmos PAO) / NASA / NASA TV / Roscosmos TV / Translation: Orbiter.ch.

Greetings, Orbiter.ch

jeudi 26 avril 2012

NASA's Cassini Finds Saturn's Moon Phoebe Has Planet-Like Qualities












NASA / ESA - Cassini - Huygens Mission to Saturn & Titan patch.

April 26, 2012

 The Face of Phoebe

Image above: Phoebe's true nature is revealed in startling clarity in this mosaic of two images taken during Cassini's flyby on June 11, 2004. Image credit: NASA/JPL/Space Science Institute.

Scientists had their first close-up look at Phoebe when Cassini began exploring the Saturn system in 2004. Using data from multiple spacecraft instruments and a computer model of the moon's chemistry, geophysics and geology, scientists found Phoebe was a so-called planetesimal, or remnant planetary building block. The findings appear in the April issue of the Journal Icarus.

"Unlike primitive bodies such as comets, Phoebe appears to have actively evolved for a time before it stalled out," said Julie Castillo-Rogez, a planetary scientist at NASA's Jet Propulsion Laboratory in Pasadena, Calif. "Objects like Phoebe are thought to have condensed very quickly. Hence, they represent building blocks of planets. They give scientists clues about what conditions were like around the time of the birth of planets and their moons."

Cassini images suggest Phoebe originated in the far-off Kuiper Belt, the region of ancient, icy, rocky bodies beyond Neptune's orbit. Data show Phoebe was spherical and hot early in its history, and has denser rock-rich material concentrated near its center. Its average density is about the same as Pluto, another object in the Kuiper Belt. Phoebe likely was captured by Saturn's gravity when it somehow got close to the giant planet.


Image above: This panel of images shows the nearly spherical shape of Saturn's moon Phoebe, as derived from imaging obtained from NASA's Cassini spacecraft. Each image represents a 90-degree turn. Image credit: NASA/JPL-Caltech/SSI/Cornell.

Saturn is surrounded by a cloud of irregular moons that circle the planet in orbits tilted from Saturn's orbit around the sun, the so-called equatorial plane. Phoebe is the largest of these irregular moons and also has the distinction of orbiting backward in relation to the other moons. Saturn's large moons appear to have formed from gas and dust orbiting in the planet's equatorial plane. These moons currently orbit Saturn in that same plane.

"By combining Cassini data with modeling techniques previously applied to other solar system bodies, we've been able to go back in time and clarify why it is so different from the rest of the Saturn system," said Jonathan Lunine, a co-author on the study and a Cassini team member at Cornell University, Ithaca, N.Y.

Analyses suggest that Phoebe was born within the first 3 million years of the birth of the solar system, which occurred 4.5 billion years ago. The moon may originally have been porous but appears to have collapsed in on itself as it warmed up. Phoebe developed a density 40 percent higher than the average inner Saturnian moon.

A Skyline View. Image Credit: NASA/JPL/Space Science Institute

Objects of Phoebe's size have long been thought to form as "potato-shaped" bodies and remained that way over their lifetimes. If such an object formed early enough in the solar system's history, it could have harbored the kinds of radioactive material that would produce substantial heat over a short timescale. This would warm the interior and reshape the moon.

"From the shape seen in Cassini images and modeling the likely cratering history, we were able to see that Phoebe started with a nearly spherical shape, rather than being an irregular shape later smoothed into a sphere by impacts," said co-author Peter Thomas, a Cassini team member at Cornell.

Phoebe likely stayed warm for tens of millions of years before freezing up. The study suggests the heat also would have enabled the moon to host liquid water at one time. This could explain the signature of water-rich material on Phoebe's surface previously detected by Cassini.

The new study also is consistent with the idea that several hundred million years after Phoebe cooled, the moon drifted toward the inner solar system in a solar-system-wide rearrangement. Phoebe was large enough to survive this turbulence.

Artist's concept of Cassini's Saturn Orbit Insertion

More than 60 moons are known to orbit Saturn, varying drastically in shape, size, surface age and origin. Scientists using both ground-based observatories and Cassini's cameras continue to search for others.

The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. JPL manages the mission for the agency's Science Mission Directorate in Washington. The California Institute of Technology in Pasadena manages JPL for NASA.

For more information on the Cassini mission, visit: http://saturn.jpl.nasa.gov and http://www.nasa.gov/cassini and http://www.esa.int/esaMI/Cassini-Huygens/

Images (mentioned), Text, Credits: NASA / Dwayne Brown / JPL / Jia-Rui C. Cook.

Cheers, Orbiter.ch

NASA's WISE Catches Aging Star Erupting With Dust









NASA - WISE Mission patch.

04.26.12


It's a dust bunny of cosmic proportions. Astronomers used images from NASA's Wide-field Infrared Survey Explorer, or WISE, to locate an aging star shedding loads of dust (orange dot at upper left). Image credit: NASA/JPL-Caltech.

Images from NASA's Wide-field Infrared Survey Explorer (WISE) reveal an old star in the throes of a fiery outburst, spraying the cosmos with dust. The findings offer a rare, real-time look at the process by which stars like our sun seed the universe with building blocks for other stars, planets and even life.

The star, catalogued as WISE J180956.27-330500.2, was discovered in images taken during the WISE survey in 2010, the most detailed infrared survey to date of the entire celestial sky. It stood out from other objects because it glowed brightly with infrared light. When compared to images taken more than 20 years ago, astronomers found the star was 100 times brighter.

"We were not searching specifically for this phenomenon, but because WISE scanned the whole sky, we can find such unique objects," said Poshak Gandhi of the Japan Aerospace Exploration Agency (JAXA), lead author of a new paper to be published in the Astrophysical Journal Letters.

Results indicate the star recently exploded with copious amounts of fresh dust, equivalent in mass to our planet Earth. The star is heating the dust and causing it to glow with infrared light.

"Observing this period of explosive change while it is actually ongoing is very rare," said co-author Issei Yamamura of JAXA. "These dust eruptions probably occur only once every 10,000 years in the lives of old stars, and they are thought to last less than a few hundred years each time. It's the blink of an eye in cosmological terms."

The aging star is in the "red giant" phase of its life. Our own sun will expand into a red giant in about 5 billion years. When a star begins to run out of fuel, it cools and expands. As the star puffs up, it sheds layers of gas that cool and congeal into tiny dust particles. This is one of the main ways dust is recycled in our universe, making its way from older stars to newborn solar systems. The other way, in which the heaviest of elements are made, is through the deathly explosions, or supernovae, of the most massive stars.

"It's an intriguing glimpse into the cosmic recycling program," said Bill Danchi, WISE program scientist at NASA Headquarters in Washington. "Evolved stars, which this one appears to be, contribute about 50 percent of the particles that make up humans."

Astronomers know of one other star currently pumping out massive amounts of dust. Called Sakurai's Object, this star is farther along in the aging process than the one discovered recently by WISE.

After Poshak and his team discovered the unusual, dusty star with WISE, they went back to look for it in previous infrared all-sky surveys. The object was not seen at all by the Infrared Astronomical Satellite (IRAS), which flew in 1983, but shows up brightly in images taken as part of the Two Micron All-Sky Survey (2MASS) in 1998.

Artist view of Wide-field Infrared Survey Explorer or WISE

Poshak and his colleagues calculated the star appears to have brightened dramatically since 1983. The WISE data show the dust has continued to evolve over time, with the star now hidden behind a very thick veil. The team plans to follow up with space- and ground-based telescopes to confirm its nature and to better understand how older stars recycle dust back into the cosmos.

NASA's Jet Propulsion Laboratory, Pasadena, Calif., manages and operates WISE for NASA's Science Mission Directorate in Washington. The spacecraft was put into hibernation mode after it scanned the entire sky twice, completing its main objectives. The principal investigator for WISE, Edward Wright, is at the University of California, Los Angeles. The mission was selected competitively under NASA's Explorers Program managed by the agency's Goddard Space Flight Center in Greenbelt, Md. The science instrument was built by the Space Dynamics Laboratory in Logan, Utah. The spacecraft was built by Ball Aerospace & Technologies Corp. in Boulder, Colo. Science operations and data processing take place at the Infrared Processing and Analysis Center at the California Institute of Technology (Caltech) in Pasadena. Caltech manages JPL for NASA.

The IRAS mission was a collaborative effort between NASA (JPL), the Netherlands and the United Kingdom. The 2MASS mission was a joint effort between Caltech, the University of Massachusetts and NASA (JPL). Data are archived at the Infrared Processing and Analysis Center at Caltech.

More information about WISE is online at http://www.nasa.gov/wise , http://wise.astro.ucla.edu and http://jpl.nasa.gov/wise

Images, Text, Credits: NASA / J.D. Harrington / JPL / Whitney Clavin.

Best regards, Orbiter.ch

First Mars Express gravity results plot volcanic history












ESA - Mars Express Mission patch.

26 April 2012

Five years of Mars Express gravity mapping data are providing unique insights into what lies beneath the Red Planet’s largest volcanoes. The results show that the lava grew denser over time and that the thickness of the planet's rigid outer layers varies across the Tharsis region.

The measurements were made while Mars Express was at altitudes of between 275–330 km above the Tharsis volcanic ‘bulge’ during the closest points of its eccentric orbit, and were combined with data from NASA’s Mars Reconnaissance Orbiter.

video
Mars Express radio science experiment

The Tharsis bulge includes Olympus Mons – the tallest volcano in the Solar System, at 21 km – and the three smaller Tharsis Montes that are evenly spaced in a row.

The region is thought to have been volcanically active until 100-250 million years ago, relatively recent on a geological timescale.

The large mass of the volcanoes caused tiny ‘wobbles’ in the trajectory of Mars Express as it flew overhead; these were measured from Earth via radio tracking and translated into measurements of density variations below the surface. 

Overall, the high density of the volcanoes corresponds to a basaltic composition that is in agreement with the many martian meteorites that have fallen to Earth.

Tharsis Montes trio and Olympus Mons

The new data also reveal how the lava density changed during the construction of the three Tharsis Montes volcanoes. They started with a lighter andesitic lava that can form in the presence of water, and were then overlaid with heavier basaltic lava that makes up the visible surface of the martian crust.

“Combined with the varying height of the volcanoes, we can say that Arsia Mons is the oldest, then Pavonis Mons formed and finally Ascraeus Mons,” says Mikael Beuthe of the Royal Observatory of Belgium and lead author of the paper published in the Journal of Geophysical Research.

At Ascraeus Mons, however, the density of the lava decreased at a later stage, so that the top of the volcano is of lower density.”

The transition could reflect changes in heating beneath the surface in the form of a single mantle plume – an upwelling of abnormally hot rock from deeper within the viscous mantle, created in a process that can be likened to a lava lamp but on a gigantic scale – that slowly moved sideways to create each of the three Tharsis Montes in turn. This is the exact opposite of Earth where ‘plates’ of crust move above a stationary plume to form chains of volcanoes, such as the Hawaiian islands.

The data also describe the thickness of the lithosphere – the outermost shell of the planet, including the upper portion of the mantle – and find surprising lateral variations between Olympus Mons and the Tharsis Montes, with the three smaller volcanoes having a much higher density underground ‘root’ than Olympus Mons.

Olympus Mons topography

These roots could be dense pockets of solidified lava or an ancient network of underground magma chambers.

“The lack of a high-density root below Olympus Mons indicates it was built on a lithosphere of high rigidity, while the other volcanoes partially sank into a less rigid lithosphere,” says co-author Veronique Dehant, also of the Royal Observatory of Belgium. “This tells us that there were large spatial variations in the heat flux from the mantle at the time of their formation.”

Since the three Tharsis Montes sit on top of the Tharsis bulge, whereas Olympus Mons stands on the edge, the greater crustal thickness at the centre may have acted as an insulating lid to increase the temperature, creating a less rigid lithosphere. Here rising magma interacted with the pre-existing bulge, whereas the magma forming Olympus Mons ascended through the older crust that is supporting the Tharsis bulge, perhaps creating the observed density differences between the volcanoes.

“These results show that data on the Mars interior are key to understanding the evolution of the Red Planet,” says Olivier Witasse, ESA Mars Express Project Scientist. “One option for a future mission to Mars would be a network of small landers, simultaneously measuring seismic activity in order to probe the interior.

Related links:

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

Behind the lens: http://www.esa.int/SPECIALS/Mars_Express/SEMSXE1PGQD_0.html

Frequently asked questions: http://www.esa.int/SPECIALS/Mars_Express/SEM76D9OY2F_0.html

For specialists:

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/

Images, Animation, Credits: ESA / NASA / DLR / FU Berlin (G. Neukum) / Royal Observatory of Belgium.

Greetings, Orbiter.ch

mercredi 25 avril 2012

Adjusted! The orbit of the ISS












ESA - ATV-3 Edoardo Amaldi Mission patch.

April 25, 2012

Mission Control Center (MCC) has completed an operation to increase the average altitude of the International Space Station (ISS).

Adjustments be conducted using two main engines of the orbital control system (Orbital Control System - OCS) of the European cargo spacecraft ATV-3 "Edoardo Amaldi." Maintaining the desired spatial position of the ISS provides orientation engines of the Russian Service Module "Zvezda" and the cargo ship "Progress M-15M."

ATV re-boost ISS. Credit: ESA

The operation carried out in order to form a working orbit station to provide the necessary conditions for landing manned spacecraft "Soyuz TMA-22", which is scheduled for April 27.

The average height of the orbit of the ISS increased by 4.1 kilometers and is 395.3 kilometers.

Original text in Russian: http://www.federalspace.ru/main.php?id=2&nid=19008

Image, Text, Credits: Press-service of Federal Space Agency (Roscosmos PAO) and the PCO / ESA / Translation: Orbiter.ch.

Best regards, Orbiter.ch

NASA Dawn Spacecraft Reveals Secrets of Giant Asteroid Vesta












NASA - Dawn Mission patch.

April 25, 2012

Findings from NASA's Dawn spacecraft reveal new details about the giant asteroid Vesta, including its varied surface composition, sharp temperature changes and clues to its internal structure. The findings were presented today at the European Geosciences Union meeting in Vienna, Austria and will help scientists better understand the early solar system and processes that dominated its formation.


Image above: These composite images from the framing camera aboard NASA’s Dawn spacecraft show three views of a terrain with ridges and grooves near Aquilia crater in the southern hemisphere of the giant asteroid Vesta. Image credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA.

Spacecraft images, taken 420 miles (680 kilometers) and 130 miles (210 kilometers) above the surface of the asteroid, show a variety of surface mineral and rock patterns. Coded false-color images help scientists better understand Vesta's composition and enable them to identify material that was once molten below the asteroid's surface.

Researchers also see breccias, which are rocks fused during impacts from space debris. Many of the materials seen by Dawn are composed of iron- and magnesium-rich minerals, which often are found in Earth's volcanic rocks. Images also reveal smooth pond-like deposits, which might have formed as fine dust created during impacts settled into low regions.


Image above: These composite images from the framing camera aboard NASA’s Dawn spacecraft show three views of the comparatively fresh crater named Vibidia on the giant asteroid Vesta. Image credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA.

"Dawn now enables us to study the variety of rock mixtures making up Vesta's surface in great detail," said Harald Hiesinger, a Dawn participating scientist at Münster University in Germany. "The images suggest an amazing variety of processes that paint Vesta's surface."

At the Tarpeia crater near the south pole of the asteroid, Dawn revealed bands of minerals that appear as brilliant layers on the crater's steep slopes. The exposed layering allows scientists to see farther back into the geological history of the giant asteroid.


Image above: This colorized image from NASA’s Dawn mission shows temperature variations at Tarpeia crater, near the south pole of the giant asteroid Vesta. Image credit: NASA/JPL-Caltech/UCLA/INAF.

The layers closer to the surface bear evidence of contamination from space rocks bombarding Vesta's surface. Layers below preserve more of their original characteristics. Frequent landslides on the slopes of the craters also have revealed other hidden mineral patterns.


These images of Tarpeia crater, near the south pole of the giant asteroid Vesta, were obtained by the visible and infrared mapping spectrometer on NASA’s Dawn spacecraft. Image credit: NASA/JPL-Caltech/UCLA/INAF.

"These results from Dawn suggest Vesta's 'skin' is constantly renewing," said Maria Cristina De Sanctis, lead of the visible and infrared mapping spectrometer team based at Italy's National Institute for Astrophysics in Rome.

Dawn has given scientists a near 3-D view into Vesta's internal structure. By making ultrasensitive measurements of the asteroid's gravitational tug on the spacecraft, Dawn can detect unusual densities within its outer layers. Data now show an anomalous area near Vesta's south pole, suggesting denser material from a lower layer of Vesta has been exposed by the impact that created a feature called the Rheasilvia basin. The lighter, younger layers coating other parts of Vesta's surface have been blasted away in the basin.


Image above: This set of images from NASA's Dawn mission shows topography of the southern hemisphere of the giant asteroid Vesta and a map of Vesta’s gravity variations that have been adjusted to account for Vesta’s shape. Image credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA.

Dawn obtained the highest-resolution surface temperature maps of any asteroid visited by a spacecraft. Data reveal temperatures can vary from as warm as -10 degrees Fahrenheit (-23 degrees Celsius) in the sunniest spots to as cold as -150 degrees Fahrenheit (-100 degrees Celsius) in the shadows. This is the lowest temperature measurable by Dawn. These findings show the surface responds quickly to illumination with no mitigating effect of an atmosphere.

video

Video above: Vesta Shape and Gravity - This video from NASA's Dawn mission shows that the gravity field of Vesta closely matches the surface topography of the giant asteroid Vesta. The video shows shaded topography from Dawn's framing camera on the left, with troughs and craters visible, and color-contoured data from Dawn's gravity experiment on the right. Red shows the areas with a higher than average gravity field and blue-purple shows the areas where the field is weaker on average. The highest topography, on the rim of the Rheasilvia basin deep in the southern hemisphere, shows a particularly strong gravity field.

"After more than nine months at Vesta, Dawn's suite of instruments has enabled us to peel back the layers of mystery that have surrounded this giant asteroid since humankind first saw it as just a bright spot in the night sky," said Carol Raymond, Dawn deputy principal investigator at NASA's Jet Propulsion Laboratory (JPL) in Pasadena, Calif. "We are closing in on the giant asteroid's secrets."

Launched in 2007, Dawn began its exploration of the approximately 330-mile- (530-kilometer-) wide asteroid in mid-2011. The spacecraft's next assignment will be to study the dwarf planet Ceres in 2015. These two icons of the asteroid belt have been witness to much of our solar system's history.

Dawn's mission is managed by JPL 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, Ala. UCLA is responsible for overall Dawn mission science. Orbital Sciences Corp. in Dulles, Va., designed and built the spacecraft. The German Aerospace Center, the Max Planck Institute for Solar System Research, the Italian Space Agency and the Italian National Astrophysical Institute are international partners on the mission team.

To view the new images and for more information about Dawn, visit: http://www.nasa.gov/dawn and http://dawn.jpl.nasa.gov

Images (mentioned), Video, Text, Credits:  NASA / Dwayne Brown / JPL / Jia-Rui Cook.

Greetings, Orbiter.ch

A Cluster Within a Cluster












ESO - European Southern Observatory logo.

25 April 2012

 The star cluster NGC 6604 and its surroundings

The star cluster NGC 6604 is shown in this new image taken by the Wide Field Imager attached to the MPG/ESO 2.2-metre telescope at the La Silla Observatory in Chile. It is often overlooked in favour of its more prominent neighbour, the Eagle Nebula (also known as Messier 16), that lies a mere wingspan away. But the framing of this picture, which places the star cluster in a landscape of surrounding gas and dust clouds, shows what a beautiful object NGC 6604 is in its own right.

The star cluster NGC 6604 in the constellation of Serpens

NGC 6604 is the bright grouping towards to the upper left of the image. It is a young star cluster that is the densest part of a more widely scattered association containing about one hundred brilliant blue-white stars [1]. The picture also shows the cluster’s associated nebula — a cloud of glowing hydrogen gas that is called Sh2-54 [2] — as well as dust clouds.

NGC 6604 lies about 5500 light-years away in the constellation of Serpens (The Serpent) and is located about two degrees north of the Eagle Nebula in the night sky (eso0926). The bright stars are easily seen in a small telescope and were first catalogued by William Herschel in 1784. However, the faint gas cloud escaped attention until the 1950s when it was catalogued by Stewart Sharpless on photographs from the National Geographic–Palomar Sky Atlas.

Wide-field view of the sky around the cluster NGC 6604

The cluster’s hot young stars are helping a new generation of stars to form in NGC 6604, by collecting star-making material into a compact region with their strong stellar winds and radiation. This second generation of stars will quickly replace the older generation, as although the brightest young stars are massive, they consume their fuel copiously and live short lives.

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Zooming in on the star cluster NGC 6604

Aside from aesthetics, NGC 6604 has other reasons to draw the gaze of astronomers, as it has a strange column of hot ionised gas emanating from it. Similar columns of hot gas, which channel outflowing material from young star clusters, have been found elsewhere in the Milky Way and other spiral galaxies, but the example in NGC 6604 is relatively nearby, allowing astronomers to study it in detail.

video
Panning across the region of the star cluster NGC 6604

This particular column (often referred to by astronomers as a “chimney”) is perpendicular to the galactic plane and stretches an incredible 650 light-years in length. Astronomers think that the hot stars within NGC 6604 are responsible for producing the chimney, but more research is needed to fully understand these unusual structures.

Notes:

[1] This stellar association is called Serpens OB. The first part of the name refers to the constellation in which it lies and the letters OB refer to the spectral type of the stars. O and B are the two hottest stellar classifications and most stars of these types are very brilliant blue-white stars, and relatively young.

[2] The name Sh2-54 means that the object is the 54th in the second Sharpless catalogue of HII regions, published in 1959.

More information:

The year 2012 marks the 50th anniversary of the founding of the European Southern Observatory (ESO). ESO is the foremost intergovernmental astronomy organisation in Europe and the world’s most productive astronomical observatory. It is supported by 15 countries: Austria, Belgium, Brazil, the Czech Republic, Denmark, France, Finland, Germany, Italy, the Netherlands, Portugal, Spain, Sweden, Switzerland and the United Kingdom. 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 the European partner of a revolutionary astronomical telescope ALMA, the largest astronomical project in existence. ESO is currently planning a 40-metre-class European Extremely Large optical/near-infrared Telescope, the E-ELT, which will become “the world’s biggest eye on the sky”.

Links:

    Photos of the MPG/ESO 2.2-metre Telescope: http://www.eso.org/public/images/archive/search/?adv=&subject_name=mpg

    Other photos taken with the MPG/ESO 2.2-metre Telescope: http://www.eso.org/public/images/archive/search/?adv=&facility=15

    Photos of La Silla: http://www.eso.org/public/images/archive/category/lasilla/

Images, Text, Credit: ESO / IAU and Sky & Telescope / Digitized Sky Survey 2 / Richard Hook / Videos: ESO / Digitized Sky Survey 2 / Nick Risinger (skysurvey.org). Music: John Dyson (from the album Moonwind).

Best regards, Orbiter.ch

mardi 24 avril 2012

Latest CryoSat result revealed







ESA - CRYOSAT Mission logo.

25 April 2012

After nearly a year and a half of operations, CryoSat has yielded its first seasonal variation map of Arctic sea-ice thickness. Results from ESA’s ice mission were presented today at the Royal Society in London.

In June 2011, the first map of Arctic sea-ice thickness was unveiled, using CryoSat data acquired between January and February of that year.

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Changes in sea-ice thickness

Now, the complete 2010–11 winter season data have been processed to produce a seasonal variation map of sea-ice thickness.

This is the first map of its kind generated using data from a radar altimeter at such a high resolution compared to previous satellite measurements.

CryoSat’s altimeter makes precise measurements of its height above the ice by measuring the time interval between the transmission and reception of very short radar pulses.

Readings over the Arctic from October 2010 to March 2011 were processed to map the seasonal formation of floating ice.

ESA and NASA have been collaborating to perform carefully coordinated flights directly under CryoSat’s orbit over the Arctic, gathering data to ensure the accuracy of the satellite measurements.

This first validated CryoSat dataset demonstrates the full potential of this innovative ice mission. 

Owing to the high rate of change in the Arctic Ocean, this has a special relevance for climate change research.

Other significant results from this collaborative European mission will be presented and discussed, with perspectives from UK industrial and scientific communities.

This event is being jointly organised by ESA and the UK Space Agency as part of the wider celebration of the 50th anniversary of the UK in space.

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CryoSat in orbit

The map, along with a full digital elevation model of Greenland and other scientific results from the collaborative European mission, were presented today at the Royal Society in London.

The event was jointly organised by ESA and the UK Space Agency as part of the wider celebration of the 50th anniversary of the UK in space.

“Within the 50th anniversary celebrations of space activities in the UK, we have today seen how the UK has been able to contribute to and lead in the many aspects of ESA’s CryoSat mission,” said David Williams, Chief Executive of the UK Space Agency.

Director of ESA’s Earth Observation Programmes, Volker Liebig, outlined the dramatic effects that climate change has had on the Arctic, and how satellites have been monitoring sea-ice for over 30 years.

"In the coming years, the Arctic will become a very important geo-political region," said Prof. Liebig.

"15 to 20 per cent of the world’s oil and gas reserves are expected there, and we will find shorter shipping routes as the ice melts. Satellites will play and ever-important role in the sustainable management of this sensitive region."

Every year, the Arctic Ocean experiences the seasonal formation and then melting of vast amounts of floating ice. Over the past decade, satellites have seen an acceleration in the rate of overall sea ice loss.

Radars on satellites such as ESA’s CryoSat can acquire high-resolution images through clouds and darkness. This is particularly useful when observing the inaccessible Arctic, which is prone to long periods of bad weather and extended darkness.

In the coming years, CryoSat data will map precise changes in sea-ice thickness year to year, furthering our understanding of the effects that climate change has on the Arctic.

ESA’s SMOS mission is providing complementary information on sea-ice cover and the thickness of thin ice.

Related links:

UK 50 years in space: http://www.bis.gov.uk/ukspaceagency/50-years-in-space

Royal Society: http://royalsociety.org/

CryoSat: http://www.esa.int/SPECIALS/Cryosat/index.html

Access CryoSat data: https://earth.esa.int/web/guest/missions/esa-operational-eo-missions/cryosat

Animations, Text, Credits: ESA / CPOM / UCL / AOES Medialab / Planetary Visions.

Greetings, Orbiter.ch

Hubble Peeks Inside a Stellar Cloud

NASA - Hubble Space Telescope patch.

04.24.12


Bright stars, shining through what looks like a haze in the night sky, are part of a young stellar grouping in one of the largest known star formation regions of the Large Magellanic Cloud, a dwarf satellite galaxy of the Milky Way. The image was captured by the NASA/ESA Hubble Space Telescope's Wide Field Planetary Camera 2.

The stellar grouping, known to stargazers as NGC 2040 or LH 88, is a loose star cluster whose stars have a common origin and are drifting together through space. There are three different types of stellar associations defined by their stellar properties. NGC 2040 is an OB association, a grouping that usually contains 10–100 stars of type O and B--these are high-mass stars that have short but brilliant lives. It is thought that most of the stars in the Milky Way were born in OB associations.

A version of this image was entered into the Hubble’s Hidden Treasures Image Processing Competition by contestant Eedresha Sturdivant. Hidden Treasures is an initiative to invite astronomy enthusiasts to search the Hubble archive for stunning images that have never been seen by the general public.

The Hubble Space Telescope is a project of international cooperation between NASA and the European Space Agency.

For more information about Hubble visit: http://www.nasa.gov/hubble and http://hubblesite.org/

ESA Hubble site: http://www.spacetelescope.org/

Image, Text, Credit: ESA / Hubble, NASA and D. A Gouliermis. Acknowledgement: Flickr user Eedresha Sturdivant.

Greetings, Orbiter.ch

NASA's Spitzer Finds Galaxy with Split Personality












NASA - Spitzer Space Telescope patch.

04.24.12


The infrared vision of NASA's Spitzer Space Telescope has revealed that the Sombrero galaxy -- named after its appearance in visible light to a wide-brimmed hat -- is in fact two galaxies in one. Image credit: NASA/JPL-Caltech.

While some galaxies are rotund and others are slender disks like our spiral Milky Way, new observations from NASA's Spitzer Space Telescope show that the Sombrero galaxy is both. The galaxy, which is a round elliptical galaxy with a thin disk embedded inside, is one of the first known to exhibit characteristics of the two different types. The findings will lead to a better understanding of galaxy evolution, a topic still poorly understood.

"The Sombrero is more complex than previously thought," said Dimitri Gadotti of the European Southern Observatory in Chile and lead author of a new paper on the findings appearing in the Monthly Notices of the Royal Astronomical Society. "The only way to understand all we know about this galaxy is to think of it as two galaxies, one inside the other."

The Sombrero galaxy, also known as NGC 4594, is located 28 million light-years away in the constellation Virgo. From our viewpoint on Earth, we can see the thin edge of its flat disk and a central bulge of stars, making it resemble a wide-brimmed hat. Astronomers do not know whether the Sombrero's disk is shaped like a ring or a spiral, but agree it belongs to the disk class.

"Spitzer is helping to unravel secrets behind an object that has been imaged thousands of times," said Sean Carey of NASA's Spitzer Science Center at the California Institute of Technology in Pasadena. "It is intriguing Spitzer can read the fossil record of events that occurred billions of years ago within this beautiful and archetypal galaxy."


Image above: New observations from NASA's Spitzer Space Telescope reveal the Sombrero galaxy is not simply a regular flat disk galaxy of stars as previously believed, but a more round elliptical galaxy with a flat disk tucked inside. Image credit: NASA/JPL-Caltech.

Spitzer captures a different view of the galaxy than visible-light telescopes. In visible views, the galaxy appears to be immersed in a glowing halo, which scientists had thought was relatively light and small. With Spitzer's infrared vision, a different view emerges. Spitzer sees old stars through the dust and reveals the halo has the right size and mass to be a giant elliptical galaxy.

While it is tempting to think the giant elliptical swallowed a spiral disk, astronomers say this is highly unlikely because that process would have destroyed the disk structure. Instead, one scenario they propose is that a giant elliptical galaxy was inundated with gas more than nine billion years ago. Early in the history of our universe, networks of gas clouds were common, and they sometimes fed growing galaxies, causing them to bulk up. The gas would have been pulled into the galaxy by gravity, falling into orbit around the center and spinning out into a flat disk. Stars would have formed from the gas in the disk.

"This poses all sorts of questions," said Rubén Sánchez-Janssen from the European Southern Observatory, co-author of the study. "How did such a large disk take shape and survive inside such a massive elliptical? How unusual is such a formation process?"

Spitzer Space Telescope

Researchers say the answers could help them piece together how other galaxies evolve. Another galaxy, called Centaurus A, appears also to be an elliptical galaxy with a disk inside it. But its disk does not contain many stars. Astronomers speculate that Centaurus A could be at an earlier stage of evolution than the Sombrero and might eventually look similar.

The findings also answer a mystery about the number of globular clusters in the Sombrero galaxy. Globular clusters are spherical nuggets of old stars. Ellipticals typically have a few thousand, while spirals contain a few hundred. The Sombrero has almost 2,000, a number that makes sense now but had puzzled astronomers when they thought it was only a disk galaxy.

NASA's Jet Propulsion Laboratory, Pasadena, Calif., manages the Spitzer Space Telescope mission for NASA's Science Mission Directorate, Washington. Science operations are conducted at the Spitzer Science Center at the California Institute of Technology in Pasadena. Data are archived at the Infrared Science Archive housed at the Infrared Processing and Analysis Center at Caltech. Caltech manages JPL for NASA. For more information about Spitzer, visit http://spitzer.caltech.edu/ and http://www.nasa.gov/spitzer 

Images (mentioned), Text, Credits: NASA / Whitney Clavin / JPL / J.D. Harrington.

Best regards, Orbiter.ch

lundi 23 avril 2012

Cassini Spacecraft Sees New Objects Blazing Trails in Saturn Ring












NASA / ESA - Cassini Mission to Saturn patch.

April 24, 2012

Scientists working with images from NASA's Cassini spacecraft have discovered strange, half-mile-sized objects punching through one of Saturn's rings and leaving glittering trails behind them. The results will be presented tomorrow at the European Geosciences Union meeting in Vienna, Austria.

video

Video above: Images from NASA's Cassini spacecraft have revealed half-mile-sized (kilometer-sized) objects punching through parts of Saturn's F ring, leaving glittering trails behind them. These trails in the rings, which scientists are calling "mini-jets," fill in a missing link in our story of the curious behavior of the F ring. NASA/JPL-Caltech.

The penetration occurred in the outermost of Saturn's main rings, called the F ring, which has a circumference of 550,000 miles (881,000 kilometers). Scientists are calling the trails in the F ring "mini-jets." Cassini scientists combed through 20,000 images and found 500 examples of these rogues during the seven years Cassini has been at Saturn.

"Beyond just showing us the strange beauty of the F ring, Cassini's studies of this ring help us understand the activity that occurs when solar systems evolve out of dusty disks that are similar to, but obviously much grander than, the disk we see around Saturn," said Linda Spilker, Cassini project scientist at NASA's Jet Propulsion Laboratory (JPL) in Pasadena, Calif.


Image above: This set of six images obtained by NASA's Cassini spacecraft shows trails that were dragged out from Saturn's F ring by objects about a half mile (1 kilometer) in diameter. NASA/JPL-Caltech/SSI/QMUL.

Scientists have known relatively large objects can create channels, ripples and snowballs, or clumps of icy material, in the F ring. However, scientists did not know what happened to these snowballs after they were created. Some were broken up by collisions or tidal forces in their orbit around Saturn. Scientists now have evidence some of the smaller ones survived, and their differing orbits mean they go on to strike through the F ring on their own.

"I think the F ring is Saturn's weirdest ring, and these latest Cassini results go to show how the F ring is even more dynamic than we ever thought," said Carl Murray, a Cassini imaging team member based at Queen Mary University of London, U.K. "These findings show us that the F ring region is like a bustling zoo of objects from a half-mile (0.8-kilometer) in size to moons like Prometheus a hundred miles (160.9 kilometers) in size, creating a spectacular show."


Image above: The constant change in Saturn's wavy, wiggly F ring is on display in this set of images obtained by NASA's Cassini spacecraft. Image credit: NASA/JPL-Caltech/SSI/QMUL.

These small objects appear to collide with the F ring at gentle speeds about 4 mph (2 meters per second). The collisions drag glittering ice particles out of the F ring with them, leaving a trail of 20-110 miles (40-180 kilometers) long.

In some cases, the objects traveled in packs, creating mini-jets that looked exotic, like the barb of a harpoon. Other new images show grand views of the entire F ring and the swirls and eddies from the different kinds of objects moving through and around it.


Image above: This image obtained by NASA's Cassini spacecraft around the time it went into orbit around Saturn in 2004 shows a short trail of icy particles dragged out from Saturn's F ring. Image Credit: NASA/JPL-Caltech/SSI/QMUL.

Saturn's rings are comprised primarily of water ice. The chunks of ice that make up the main rings spread out 85,000 miles (140,000 kilometers) from the center of Saturn. Scientists believe the rings' average thickness is approximately 30 feet (10 meters).


This set of four images obtained by NASA's Cassini spacecraft shows some of the more bizarre trails that were dragged out from Saturn's F ring by objects about a half mile (1 kilometer) in diameter. Image credit: NASA/JPL-Caltech/SSI/QMUL.

The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. JPL manages the mission for NASA's Science Mission Directorate in Washington. The imaging team is based at the Space Science Institute in Boulder, Colo.

New images and movies of the mini-jets are available at: http://www.nasa.gov/mission_pages/cassini/whycassini/cassini20120423.html

For information about Cassini, visit: http://www.nasa.gov/cassini and http://www.esa.int/esaMI/Cassini-Huygens/

Images (mentioned), Video (mentioned), Text, Credits: NASA / Dwayne Brown / JPL / Jia-Rui C. Cook.

Greetings, Orbiter.ch