vendredi 11 octobre 2013

Water-rich Planetary Building Blocks Found Around White Dwarf












NASA - Hubble Space Telescope patch.

Oct. 10, 2013

Astronomers using NASA's Hubble Space Telescope have found the building blocks of solid planets that are capable of having substantial amounts of water. This rocky debris, currently orbiting a white dwarf star called GD 61, is considered a relic of a planetary system that survived the burnout of its parent star. The finding suggests that the star system — located about 150 light-years away and at the end of its life — had the potential to contain Earth-like exoplanets, the researchers say.

"These water-rich building blocks, and the terrestrial planets they assemble, may in fact be common. A system cannot create things as big as asteroids and avoid building planets, and GD 61 had the ingredients to deliver lots of water to their surfaces," according to Jay Farihi of the University of Cambridge, United Kingdom. Though it's hard to predict exactly what types of planets there might have been, Farihi emphasized that, "Our results demonstrate that there was definitely potential for habitable planets in this exoplanetary system. The system almost certainly had (and possibly still has) planets, and it had the ingredients to deliver lots of water to their surfaces."

The new research findings are reported today in the journal Science.


Image above: This is an artist's impression of a rocky and water-rich asteroid being torn apart by the strong gravity of the white dwarf star GD 61. Similar objects in our solar system likely delivered the bulk of water on Earth and represent the building blocks of the terrestrial planets.

Observations made with Hubble's Cosmic Origins Spectrograph (COS) allowed the team, led by Farihi, to do a robust chemical analysis of the debris falling into GD 61. The discovery complements other leading astronomical observations that measure the size and density of planets, but not their actual composition, say researchers.

"The only feasible way to see what a distant planet is made of is to take it apart, and nature does this for us using the strong gravitational tidal forces of white dwarf stars," said Farihi. "This technique allows us to look at the chemistry that builds rocky planets, and is a completely independent method from other types of exoplanet observations."

The white dwarf GD 61 is a relic of a star that once burned hotter and brighter than our Sun. The star exhausted its fuel in just 1.5 billion years. (Our Sun will last roughly ten times as long.)

NASA's Far Ultraviolet Space Explorer (FUSE) first found an abundance of oxygen in the dwarf's atmosphere in 2008. Eventually astronomers realized that this was the telltale signature of material falling into the star and polluting its atmosphere. White dwarfs typically have pure hydrogen or pure helium atmospheres. The "polluted white dwarf" scenario was bolstered by NASA Spitzer Space Telescope observations in 2011, which showed that the star has a tightly orbiting disk containing debris that falls onto the star and contaminates the otherwise pristine atmosphere.

The only way to obtain a more precise measurement of the amount of oxygen in the debris around GD 61 requires observations in the ultraviolet, which can only be carried out above Earth's atmosphere. The team used COS aboard Hubble to obtain the required data. The COS observations were then analyzed by Detlev Koester of the University of Kiel, in Germany, using a computer model of the white dwarf atmosphere to derive the elemental abundances.

Combing their results with a previous study that used the W. M. Keck Observatory on the summit of Mauna Kea, Hawaii, the team also detected magnesium, silicon, and iron, which, together with oxygen, are the main components of rocks. By counting the number of these elements relative to oxygen the researchers were able to predict how much oxygen should be in the atmosphere of the white dwarf. They found significantly more oxygen than should have been carried by rocky minerals alone. "The oxygen excess can be carried by either water or carbon mono- or dioxide. In this star there is virtually no carbon, indicating there must have been substantial water," said Boris Gnsicke of the University of Warwick, in Coventry, United Kingdom. He added that the small amount of carbon seen in the white dwarf rules out comets as the source of water. Comets are rich in both water and carbon compounds.

Artist's impression of the ESA / NASA Hubble Space Telescope in its orbit 600 km above the Earth

In their Hubble survey the team observed nearly 100 white dwarfs. Analysis is still ongoing, but the team estimates that at least 20 percent of the dwarfs show ongoing accretion of planetary debris, and it could possibly be as high as 50 percent.

How do the asteroids fall into the stellar remnant? The best model at present is based on how Jupiter perturbs members of our main asteroid belt. The Kirkwood Gaps in the asteroid belt represent areas where asteroids lose energy to Jupiter and sometimes fall into the Sun.

Infrared observations using the Spitzer telescope show that Sun-like stars that are similar to the parent star of GD 61 have inner debris belts analogous to our main asteroid belt. And, interestingly, these systems appear to have a gap just outside their inner belts that may be caused by one or more planets, say the investigators. "It looks like a pattern of a planet next to an asteroid belt whose members get thrown into the star may be a common feature of solar systems," said Farihi.

Earth is essentially a "dry" planet, with only 0.02 percent of its mass as surface water. So oceans came long after it had formed, most likely when water-rich asteroids in the solar system crashed into our planet.

The new discovery shows that the same water "delivery system" could have occurred in this distant, dying star's solar system — as this latest evidence points to it containing a similar type of water-rich asteroid that would have first brought water to Earth.

Six billion years from now an alien astronomer measuring similar abundances in the atmosphere of our burned-out Sun may reach the same conclusion that terrestrial planets once circled our parent star. Though the progenitor star was different from our Sun, nevertheless, "it's a look into our future," said Gänsicke.

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

For more information about Hubble Space Telescope, visit: http://hubblesite.org/ and http://www.spacetelescope.org/

Artwork Credits: NASA, ESA, M.A. Garlick (space-art.co.uk), University of Warwick, and University of Cambridge.

Science Credits: NASA, ESA, J. Farihi (University of Cambridge), B. Gänsicke (University of Warwick), and D. Koester (University of Kiel).

Text, Credits: Space Telescope Science Institute, Baltimore, Md. / Ray Villard / University of Cambridge, Institute of Astronomy / Jay Farihi.

Best regards, Orbiter.ch

Rosetta: 100 days to wake-up












ESA - Rosetta Mission patch.

11 October 2013

ESA’s comet-chasing mission Rosetta will wake up in 100 days’ time from deep-space hibernation to reach the destination it has been cruising towards for a decade.

Comets are the primitive building blocks of the Solar System and the likely source of much of Earth’s water, perhaps even delivering to Earth the ingredients that helped life evolve.

By studying the nature of a comet close up with an orbiter and lander, Rosetta will show us more about the role of comets in the evolution of the Solar System.

Rosetta’s twelve-year journey in space

Rosetta was launched on 2 March 2004, and through a complex series of flybys – three times past Earth and once past Mars – set course to its destination: comet 67P/Churyumov–Gerasimenko. It also flew by and imaged two asteroids, Steins on 5 September 2008 and Lutetia on 10 July 2010.

In July 2011 Rosetta was put into deep-space hibernation for the coldest, most distant leg of the journey as it travelled some 800 million kilometres from the Sun, close to the orbit of Jupiter. The spacecraft was oriented so that its solar wings faced the Sun to receive as much sunlight as possible, and it was placed into a slow spin to maintain stability.

Now, as both the comet and the spacecraft are on the return journey back into the inner Solar System, the Rosetta team is preparing for the spacecraft to wake up.

Rosetta’s internal alarm clock is set for 10:00 GMT on 20 January 2014.

Once it wakes up, Rosetta will first warm up its navigation instruments and then it must stop spinning to point its main antenna at Earth, to let the ground team know it is still alive.

“We don’t know exactly at what time Rosetta will make first contact with Earth, but we don’t expect it to be before about 17:45 GMT on the same day,” says Fred Jansen, ESA’s Rosetta mission manager.

Rosetta mission milestones 2014-2015

“We are very excited to have this important milestone in sight, but we will be anxious to assess the health of the spacecraft after Rosetta has spent nearly 10 years in space.”

After wake-up, Rosetta will still be about 9 million km from the comet. As it moves closer, the 11 instruments on the orbiter and 10 on the lander will be turned on and checked.

In early May, Rosetta will be 2 million km from its target, and towards the end of May it will execute a major manoeuvre to line up for rendezvous with the comet in August.

The first images of a distant 67P/Churyumov–Gerasimenko are expected in May, which will dramatically improve calculations of the comet’s position and orbit.

Closer in, Rosetta will take thousands of images that will provide further details of the comet’s major landmarks, its rotation speed and spin axis orientation.

Rosetta will also make important measurements of the comet’s gravity, mass and shape, and will make an initial assessment of its gaseous, dust-laden atmosphere, or coma.

Rosetta’s Philae lander on comet nucleus

Rosetta will also probe the plasma environment and analyse how it interacts with the Sun’s outer atmosphere, the solar wind.

After extensive mapping of the comet’s surface during August and September, a landing site for the 100 kg Philae probe will be chosen. It will be first time that landing on a comet has ever been attempted.

Given the almost negligible gravity of the comet’s 4 km-wide nucleus, Philae will ‘dock’ with it using ice screws and harpoons to stop it from rebounding back into space.

Philae will send back a panorama of its surroundings and very high-resolution pictures of the surface and will perform on-the-spot analysis of the composition of the ices and organic material. A drill will take samples from 20–30 cm below the surface, feeding them to the onboard laboratory for analysis.

“The focus of the mission then moves towards what we call the ‘escort’ phase, whereby Rosetta will stay alongside the comet as it moves closer to the Sun,” notes Fred.

The comet will reach its closest distance to the Sun on 13 August 2015 at about 185 million km, roughly between the orbits of Earth and Mars.

As the comet hurtles through the inner Solar System at around 100 000 km/h, the relative speed between orbiter and comet will remain equivalent to walking pace. During this ‘escort’ phase the orbiter will continue to analyse dust and gas samples while monitoring the ever-changing conditions on the surface as the comet warms up and its ices sublimate.

ESA Rosetta spacecraft

“This unique science period will reveal the dynamic evolution of the nucleus as never seen before, allowing us to build up a thorough description of all aspects of the comet, its local environment and revealing how it changes even on a daily basis,” says Matt Taylor, ESA’s Rosetta project scientist.

Rosetta will follow the comet throughout the remainder of 2015, as it heads away from the Sun and activity begins to subside.

“For the first time we will be able to analyse a comet over an extended period of time – it is not just a flyby. This will give us a unique insight into how a comet ‘works’ and ultimately help us to decipher the role of comets in the formation of the Solar System,” adds Matt.

Rosetta Flybys:

Images taken by Rosetta during flybys of Earth and Mars, and asteroids Steins and Lutetia: http://www.esa.int/Our_Activities/Space_Science/Highlights/Rosetta_flybys

Related links:

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

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

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

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

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

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

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

Images, Video, Text, Credits: ESA / AOES Medialab.

Greetings, Orbiter.ch

jeudi 10 octobre 2013

Astronaut Scott Carpenter, second American to orbit the Earth, dies at 88














NASA - Mercury 7 Mission patch.

Oct. 10, 2013

Scott Carpenter, the fourth U.S. astronaut to fly in space and the second to orbit the Earth, died Thursday at a Denver hospice.

Carpenter’s wife, Patty, confirmed his death to Fox News. Carpenter, 88, of Vail, Colo., recently suffered a stroke.

Along with John Glenn, who flew three months before him, Carpenter was one of the last two surviving original Mercury 7 astronauts for the fledgling U.S. space program.

Astronaut Scott Carpenter

He was chosen in 1959 to be one of NASA’s first astronauts and flew on his one and only space mission on May 24, 1962, circling the Earth three times while conducting scientific experiments.

As an astronaut and aquanaut who lived underwater for the U.S. Navy, Carpenter was the first man to explore both the depths of the ocean and the heights of space.

Carpenter gave the famous send-off -- "Godspeed, John Glenn" -- when Glenn became the first American in orbit in February 1962.

Three months later, Carpenter orbited the Earth three times. He lost contact with NASA during the off-target landing but was found safely floating in his life raft 288 miles away.

The fallout from that missed landing was a factor that kept NASA from launching Carpenter into space again. So he went from astronaut to "aquanaut" and lived at length on the sea floor -- the only man to ever formally explore the two frontiers.

Scott Carpenter in his spacesuit in 1962

The launch into space was nerve-racking for the Navy pilot on the morning of May 24, 1962.

"You're looking out at a totally black sky, seeing an altimeter reading of 90,000 feet and realize you are going straight up. And the thought crossed my mind: What am I doing?" Carpenter said 49 years later in a joint lecture with Glenn at the Smithsonian Institution.

For Carpenter, the momentary fear was worth it, he said in 2011: "The view of Mother Earth and the weightlessness is an addictive combination of senses."

Astronaut Bio: Scott Carpenter - NASA: http://www.jsc.nasa.gov/Bios/htmlbios/carpenter-ms.html

Images, Text, Credits: AP / NASA.

Greetings, Orbiter.ch

Soft shells and strange star clusters












ESA - Hubble Space Telescope logo.

10 October 2013

 Hubble image of PGC 6240

The beautiful, petal-like shells of galaxy PGC 6240 are captured here in intricate detail by the NASA/ESA Hubble Space Telescope, set against a sky full of distant background galaxies. This cosmic bloom is of great interest to astronomers due to both its uneven structure, and the unusual clusters of stars that orbit around it — two strong indications of a galactic merger in the recent past.

PGC 6240 is an elliptical galaxy that resembles a pale rose in the sky, with hazy shells of stars encircling a very bright centre. Some of these shells are packed close to the centre of the galaxy, while others are flung further out into space. Several wisps of material have been thrown so far that they appear to be almost detached from the galaxy altogether.

Wide field image of PGC 6240 (ground-based image)

Astronomers have studied PGC 6240 in detail due to this structure, and also because of its surrounding globular clusters — dense, tightly packed groups of gravitationally bound stars that orbit galaxies. Over 150 of these clusters orbit our own galaxy, the Milky Way, all composed of old stars.

All the globular clusters around a certain galaxy form at approximately the same time, giving them all the same age. This is echoed within the clusters — all the stars within a single cluster form at around the same time, too. Because of this, most galaxies have cluster populations of pretty similar ages, both in terms of overall cluster, and individual stars. However, PGC 6240 is unusual in that its clusters are varied — while some do contain old stars, as expected, others contain younger stars which formed more recently.

Zooming in on PGC 6240

The most likely explanation for both the galaxy’s stacked shell structure and the unexpectedly young star clusters is that PGC 6240 merged with another galaxy at some point in the recent past. Such a merger would send ripples through the galaxy and disrupt its structure, forming the concentric shells of material seen here. It would also ignite a strong burst of star formation in the galaxy, which would then trigger similar activity in nearby space — leading to the creation of new, younger globular clusters around PGC 6240.

PGC 6240 is an elliptical galaxy in the southern constellation of Hydrus (The Water Snake). Also visible in this region are numerous background galaxies, speckled across the sky behind PGC 6240. Even though these bodies are at such vast distances from us, it is possible to make out the structure of many of the galaxies, especially the small spirals that stand out colourfully against the dark sky.

Panning across PGC 6240

A version of this image was entered into the Hubble’s Hidden Treasures image processing competition by contestant Judy Schmidt.

Notes:

[1] 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 competition is now closed, and the list of winners is available here.
More information

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/

Hubble’s Hidden Treasures: http://www.spacetelescope.org/projects/hiddentreasures/contest/

Images, Text, Credits: ESA / Hubble & NASA / Acknowledgement: Judy Schmidt / Digitized Sky Survey 2 / Videos: NASA, ESA, Digitized Sky Survey 2. Music: movetwo. Acknowledgement: Judy Schmidt.

Best regards, Orbiter.ch

Martian scars












ESA - Mars Express Mission patch.

10 October 2013

 Hebes Chasma

Ripped apart by tectonic forces, Hebes Chasma and its neighbouring network of canyons bear the scars of the Red Planet’s early history.

ESA’s Mars Express has flown over this region of Mars on numerous occasions, but this new eight-image mosaic reveals Hebes Chasma in full and in greater detail than ever (click image for full mosaic).

Hebes Chasma is an enclosed, almost 8 km-deep trough stretching 315 km in an east–west direction and 125 km from north to south at its widest point. It sits about 300 km north of the vast Valles Marineris canyon complex.

Hebes Chasma in context

The origin of Hebes Chasma and neighbouring canyons is associated with the nearby volcanic Tharsis Region, home to the largest volcano in the Solar System, Olympus Mons.

As the Tharsis bulge swelled with magma during the planet’s first billion years, the surrounding crust was stretched, eventually ripping apart and collapsing into gigantic troughs, including Hebes Chasma. Intricate fault patterns can be seen all around the deep depression – they are especially evident in the main colour and 3D images.

In the centre of Hebes Chasma, there is a flat-topped ‘mesa’ that rises to level similar to that of the surrounding plains. It is shown from different angles in the two perspective images below.

 Hebes Chasma topography

No other canyon on Mars has a similar feature and its origin is not entirely clear. Its layers include volcanic materials – just like in the main canyon walls – but also wind-blow dust and lake sediments that were laid down over time.

A horseshoe-shaped chunk has been taken out of one side of the mesa, seen below, where material has slumped down onto the valley floor below.

A landslide may also be responsible for the dark patch in this image, which appears to pool like spilt ink across the debris. It is most likely loose dust that has slid down the walls, perhaps helped along where melting ice or ground-water weakened the rocks to create a flow-like feature. A similar feature is visible at the opposite end of the mound, as seen in the full-colour image.

Hebes Chasma in perspective (3D)

Other landslide deposits are seen all over the floor of Hebes Chasma, many coming from the main canyon walls. Numerous grooves are etched into both the canyon walls and the mesa, suggesting the material is weak and easily eroded.

Landslides and rock layers inside Hebes Chasma

In the second perspective view above, a thin band of darker material is seen between two layers of light material. One idea is that the material was blown or slid from the top of the mound and collected on the slopes below. Dark material is also seen around the base of the mesa, which either eroded away from the younger sediment layers located higher up in the mesa, or were deposited separately by wind or water.

Other layers revealed in the sides of the mesa may also have been deposited by water. Data from both Mars Express and NASA’s Mars Reconnaissance Orbiter reveal that some parts of Hebes Chasma are laced with minerals that can form only in the presence of water, suggesting that at some point in the Red Planet’s history the canyon might have been filled with a lake.

Hebes Chasma in 3D

However, it is apparent from the chaotic debris that fills the canyon floor that enormous landslides have also played a key role in shaping and widening this deep scar since its formation.

Related links:

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

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

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

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/

Mars Express blog: http://blogs.esa.int/mex/

Mars Webcam: http://blogs.esa.int/vmc

Images, Text, Credits: ESA / DLR / FU Berlin (G. Neukum)/NASA MGS MOLA Science Team.

Cheers, Orbiter.ch

mercredi 9 octobre 2013

ESA and NASA stumped by cosmic mystery














ESA - European Space Agency patch / NASA - JUNO Launch Mission patch.

9 October 2013

A mystery that has stumped scientists for decades might be one step closer to solution after ESA tracking stations carefully record signals from NASA’s Juno spacecraft as it swings by Earth today.

NASA’s deep-space probe will zip past to within 561 km at 19:21 GMT as it picks up a gravitational speed boost to help it reach Jupiter in 2016.

Juno approaching Earth

During the high-speed event, radio signals from the 3225 kg Juno will be carefully recorded by ESA tracking stations in Argentina and Australia.

Engineers hope that the new measurements will unravel the decades-old ‘flyby anomaly’ – an unexplained variation in spacecraft speeds detected during some swingbys.

“We detected the flyby anomaly during Rosetta’s first Earth visit in March 2005,” says Trevor Morley, flight dynamics expert at ESA’s ESOC operations centre in Darmstadt, Germany.

“Frustratingly, no anomaly was seen during Rosetta's subsequent Earth flybys in 2007 and 2011. This is a real cosmic mystery that no one has yet figured out.”

Sometimes there, sometimes not

Since 1990, mission controllers at ESA and NASA have noticed that their spacecraft sometimes experience a strange variation in the amount of orbital energy they pick up from Earth during flybys, a technique routinely used to fling satellites deep into our Solar System.

The unexplained variation is noticed as a tiny difference in the expected speed gained (or lost) during the passage.

Juno trajectory past Earth

The variations are extremely small: NASA’s Jupiter probe ended up just 3.9 mm/s faster than expected when it swung past Earth in December 1990.

The largest variation– a boost of 13.0 mm/s – was seen with NASA’s NEAR asteroid craft in January 1998. Conversely, the differences during swingbys of NASA’s Cassini in 1999 and Messenger in 2005 were so small that they could not be confirmed.

The experts are stumped.

ESA stations listen for Juno

On 9 October, engineers and the flight dynamics teams at ESOC will watch closely as the Agency’s new 35 m-diameter deep-space dish in Malargüe, Argentina, and a smaller 15 m dish in Perth, Australia, track Juno starting at about 16:00 GMT.

Malargüe station

The stations will record highly precise radio-signal information that will indicate whether Juno speeds up or slows down more or less than predicted by current theories.

The results will be studied closely by ESA and NASA as well as scientists worldwide, who are hoping to see whether the anomaly is again detected.

Juno spacecraft Earth flyby animation

“Our Malargüe station is designed to track very distant and relatively slow-moving spacecraft, while Juno will pass by moving very, very fast at just 561 km altitude,” says ESA’s Daniel Firre, responsible for the tracking support at ESOC.

“This makes tracking Juno technically very challenging, but it’s how the scientific process works. Gathering more data that can be analysed by experts is critical if we are ever to solve this perplexing mystery.”

Related links:

Estrack tracking stations: http://www.esa.int/Our_Activities/Operations/Estrack_tracking_stations

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

Ground Systems Engineering: http://www.esa.int/Our_Activities/Operations/Ground_Systems_Engineering

NASA Juno mission: http://www.esa.int/Our_Activities/Operations/www.nasa-usa.de/mission_pages/juno/overview/index.html%E2%80%8E

Juno mission at SWRI: http://missionjuno.swri.edu/

Images, Video, Text, Credits: ESA / S. Marti / NASA / JPL.

Best regards, Orbiter.ch

A Close Look at the Toby Jug Nebula












ESO - European Southern Observatory logo.

9 October 2013

 The Toby Jug Nebula as seen with ESO's Very Large Telescope

ESO’s Very Large Telescope (VLT) has captured a remarkably detailed image of the Toby Jug Nebula, a cloud of gas and dust surrounding a red giant star. This view shows the characteristic arcing structure of the nebula, which, true to its name, does indeed look a little like a jug with a handle.

Located about 1200 light-years from Earth in the southern constellation of Carina (The Ship’s Keel), the Toby Jug Nebula, more formally known as IC 2220, is an example of a reflection nebula. It is a cloud of gas and dust illuminated from within by a star called HD 65750. This star, a type known as a red giant, has five times the mass of our Sun but it is in a much more advanced stage of its life, despite its comparatively young age of around 50 million years [1].

Location of the Toby Jug Nebula in the southern constellation of Carina

The nebula was created by the star, which is losing part of its mass out into the surrounding space, forming a cloud of gas and dust as the material cools. The dust consists of elements such as carbon and simple, heat-resistant compounds such as titanium dioxide and calcium oxide (lime). In this case, detailed studies of the object in infrared light point to silicon dioxide (silica) being the most likely compound reflecting the star’s light.

IC 2220 is visible as the star’s light is reflected off the grains of dust. This celestial butterfly structure is almost symmetrical, and spans about one light-year. This phase of a star’s life is short-lived and such objects are thus rare.

Wide field view of the area around the Toby Jug Nebula

Red giants are formed from stars that are ageing and approaching the final stages of their evolution. They have almost depleted their reserves of hydrogen, which fuels the reactions that occur during most of the life of a star. This causes the atmosphere of the star to expand enormously. Stars like HD 65750 burn a shell of helium outside a carbon-oxygen core, sometimes accompanied by a hydrogen shell closer to the star’s surface.

Zooming in into the Toby Jug Nebula

Billions of years in the future, our Sun will also bloat into a red giant. It is expected that the solar atmosphere will inflate well beyond the current orbit of Earth, engulfing all the inner planets in the process. By then, Earth will be already in very bad shape. The huge increase of radiation and the strong stellar winds that will accompany the process of stellar inflation will destroy all life on Earth and evaporate the water in the oceans, before the entire planet is finally melted.

Panning across a VLT view of the Toby Jug Nebula

British astronomers Paul Murdin, David Allen and David Malin gave IC 2220 the nickname of the Toby Jug Nebula because of its shape, which is similar to an old English drinking vessel of a type called a Toby Jug with which they were familiar when young.

This image was produced as part of the ESO Cosmic Gems programme [2].

Notes:

[1] Stars with more mass run through their lives much more quickly than lighter ones such as the Sun, which have lives measured in billions, rather than millions, of years.

[2] This picture comes from the ESO Cosmic Gems programme, an outreach initiative to produce images of interesting, intriguing or visually attractive objects using ESO telescopes, for the purposes of education and public outreach. The programme makes use of telescope time that cannot be used for science observations. All data collected may also be suitable for scientific purposes, and are made available to astronomers through ESO’s science archive.

More information:

ESO is the foremost intergovernmental astronomy organisation in Europe and the world’s most productive ground-based astronomical observatory by far. It is supported by 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 the 39-metre European Extremely Large optical/near-infrared Telescope, the E-ELT, which will become “the world’s biggest eye on the sky”.

Link:

ESO Cosmic Gems Programme: http://www.eso.org/public/outreach/gems/

Images, Text, Credits: ESO / IAU and Sky & Telescope / Digitized Sky Survey 2. Acknowledgement: Davide De Martin / Videos: ESO / Nick Risinger (skysurvey.org). Music: movetwo.

Greetings, Orbiter.ch

lundi 7 octobre 2013

Russian Collider

 












Nuclotron-based Ion Collider facility (NICA) logo / JINR, Dubna - logo.

Oct. 7, 2013

In Dubna, at the Institute of Nuclear Research, create a new collider. Dubbed the project is simple and beautiful - NICA. It is an abbreviation of Nuclotron-based Ion Collider facility. At the same time, the goddess of victory. The plant NICA scientists to model the first moments of creation of the universe billions of years ago. In fact, the birth of our world.

"Younger brother" of the Large Hadron Collider will appear in Dubna near Moscow. At the Joint Institute for Nuclear Research, has begun construction of domestic nuclear particle accelerator.

Joint Institute for Nuclear Research. Founded in 1956 by the Institute of Nuclear Problems of the Academy of Sciences of the Soviet Union. Located in the city of Dubna. Here, for the first time in the world created by synchrotron, proton accelerator where scientists have reached a record high at the time of energy. For his great contribution to the Institute of modern physics 105- th element of the periodic table given the name "Dubna", and the 114 th - "Flerov", in honor of Academician Georgi Flerov.

Today, in the laboratories of the Institute 7. Main research areas - nuclear physics, elementary particle physics and condensed matter.

Nuclotron-based Ion Collider facility - NICA description

NICA - no less ambitious, but less expensive installation than the CERN. 500 meters of the perimeter of the ring. As a Swiss instrument , NICA will be created in international cooperation.
In Dubna do not have to dig and dig tunnels of the mine - a project developed on the basis of already existing nuclotron. In fact - it is a cascade of three accelerators.

One of them is already in place - a superconducting ion synchrotron nuclotron. The second stage - the booster, the particles will provide the necessary intensity. Previously, it housed a magnet synchrotron. Plus two collider ring, in which the protons will collide.


Video above (in Russian): Russian Collider - Space program from October 5, 2013 (Roscosmos TV studio).

Russian collider will be the best setting for experiments on heavy-ion physics. Scientists are hoping that after the launch of the project NICA center of such research will register in the suburbs.

"There are high-energy physics. It is no less interesting, it is very popular today among physicists in this area expected to be very bright interesting discovery, namely the phase transitions of nuclear matter. In order to study them, you need to create maximum density of baryonic matter, the one that exists in neutron stars. In order to study these processes is to maximize the baryon density does not need maximum energy as the LHC or at the Brookhaven machine. Theorists have calculated that it is very close to that which is achievable today on our nuclotron", - says the director of the Laboratory of High Energies, JINR Vladimir Kekelidze.

The main difference from the Russian Collider in Switzerland is that the CERN main forces left in search of the elusive Higgs boson - the particle that gives mass to all other particles.
As for Russia, its installation will explore another area of ​​the creation of the universe billions of years ago, the formation of quarks and gluons, the particles of baryonic matter. That is, our world.


Image above: In the Nuclotron tunnel, A Butenko, left, and H Khodzhibagiyan discussing details of the facility construction. Image credit: JINR.

"Theorists have formulated the conditions under which it was possible to form the universe for the way in which it has gone. The conditions are very simple - a certain temperature (or energy) of the particles and the density of nuclear matter. When theorists have formulated these conditions , it became clear what the experiment can be put in the laboratory here on Earth to try to simulate the conditions that were in the early stages of the Universe", - says deputy chief engineer of the JINR, corresponding member of the Russian Academy of Sciences Gregory Trubnikov.

It will allow scientists to NICA closer to the conditions of a "Big Bang ", from which, according to physicists, and did our universe.

"It needs a well-defined energy to disperse the heavy nuclei . We chose gold for gold, because it is technically easier to do. On the basis of nuclotron and creates a collider. The first booster will nuclotron, LINAC, then beams will be displayed, and will be organized by the meeting of two beams in two places. One thing we are going to study the heavy ion program , to try to achieve the maximum density of baryonic matter, and watch what happens. And another will study the spin physics. Also no less interesting project ", - says Vladimir Kekelidze.

The UNK dipole magnet in the cryostat

With NICA scientists hope to uncover the structure of the universe and the mystery of its fundamental forces: dark matter, dark energy, black holes, "wormholes" and extra-dimensions.
"When you know how to form a substance formed as a matter of how it was formed, you can predict what will happen with this matter, as it will continue to evolve as it will break down and die. Generally, it is the fundamental issues that will Otgadki to understanding the evolution of our universe", - says Gregory Trubnikov.

Today, the scientific program NICA is filled with new ideas. The setup is a high energy density of matter and the enormous diversity of varieties of particles studied, offer opportunities for a wide range of applications.

This carbon therapy, testing of electronics for space programs, the transmutation of radioactive waste, new approaches to energy generation.

But the important thing is that the LHC will work in our country, not abroad. And the young Russian scientists will have a good and interesting work at home.

Launch of the first phase of the project is planned to NICA two years. And already in 2017-th nuclear scientists from Dubna wait for the start of the whole complex.

ROSCOSMOS Press Release: http://www.federalspace.ru/19876/

For more information, read "Design and Construction of Nuclotron-based Ion Collider fAcility (NICA) PDF: http://nica.jinr.ru/files/NICA_CDR.pdf

Images, Video, Text, Credits: Roscosmos TV studio / ROSCOSMOS / NICA / JINR / Translation: Orbiter.ch Aerospace.

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