vendredi 16 novembre 2012

GOCE’s second mission improving gravity map









ESA - GOCE Mission logo.

16 November 2012

ESA’s GOCE gravity satellite has already delivered the most accurate gravity map of Earth, but its orbit is now being lowered in order to obtain even better results.

The Gravity field and steady-state Ocean Circulation Explorer (GOCE) has been orbiting Earth since March 2009, reaching its ambitious objective to map our planet’s gravity with unrivalled precision.

Improved spatial resolution

Although the planned mission has been completed, the fuel consumption was much lower than anticipated because of the low solar activity over the last two years. This has enabled ESA to extend GOCE’s life, improving the quality of the gravity model.

To be able to measure the strength of Earth’s gravity, the satellite was flying in an extraordinarily low orbit about 255 km high – about 500 km lower than most Earth observation satellites.

Based on a clear preference from the GOCE user community, ESA’s Earth Scientific Advisory Committee recommended lowering the orbit to 235 km starting in August.

video
Counteracting drag

Lowering the orbit increases the accuracy and resolution of GOCE’s measurements, improving our view of smaller ocean dynamics such as eddy currents.

The control team began the manoeuvres in August, lowering GOCE by about 300 m per day.

After coming down by 8.6 km, the satellite’s performance and new environment were assessed. Now, GOCE is again being lowered while continuing its gravity mapping. Finally, it is expected to reach 235 km in February.

As the orbit drops, atmospheric drag increasingly pulls the satellite towards Earth. But GOCE was designed to fly low, the tiny thrust of its ion engine continuously compensating for any drag.

The expected increase in data quality is so high that scientists are calling it GOCE’s ‘second mission.’

New GOCE geoid

“For us at ESA, GOCE has been a fantastic mission and it continues to surprise us,” said Volker Liebig, ESA’s Director of Earth Observation Programmes.

“What the team of ESA engineers is now doing has not been done before and it poses a challenge. But it will also trigger new research in the field of gravity based on the high-resolution data we are expecting.”

The first ‘geoid’ based on GOCE’s gravity measurements was unveiled in June 2010. It is the surface of an ideal global ocean in the absence of tides and currents, shaped only by gravity.

ESA’s GOCE gravity satellite

A geoid is a crucial reference for conducting precise measurements of ocean circulation, sea-level change and ice dynamics.

The mission has also been providing new insight into air density and wind in space, and its information was recently used to produce the first global high-resolution map of the boundary between Earth’s crust and mantle.

More information:

GOCE: http://www.esa.int/SPECIALS/GOCE/index.html

Access GOCE data: http://earth.esa.int/GOCE/

Images, Video, Text, Credits: ESA / AOES Medialab / GOCE+ Theme 2 / HPF / DLR.

Best regards, Orbiter.ch

jeudi 15 novembre 2012

NASA Rover Providing New Weather and Radiation Data About Mars












NASA - Mars Science Laboratory (MSL) patch.

Nov. 15, 2012


Image above: NASA's Mars rover Curiosity used a mechanism on its robotic arm to dig up five scoopfuls of material from a patch of dusty sand called "Rocknest," producing the five bite-mark pits visible in this image from the rover's left Navigation Camera (Navcam). Image credit: NASA/JPL-Caltech.

Observations of wind patterns and natural radiation patterns on Mars by NASA's Curiosity rover are helping scientists better understand the environment on the Red Planet's surface.

Researchers using the car-sized mobile laboratory have identified transient whirlwinds, mapped winds in relation to slopes, tracked daily and seasonal changes in air pressure, and linked rhythmic changes in radiation to daily atmospheric changes. The knowledge being gained about these processes helps scientists interpret evidence about environmental changes on Mars that might have led to conditions favorable for life.

During the first 12 weeks after Curiosity landed in an area named Gale Crater, an international team of researchers analyzed data from more than 20 atmospheric events with at least one characteristic of a whirlwind recorded by the Rover Environmental Monitoring Station (REMS) instrument. Those characteristics can include a brief dip in air pressure, a change in wind direction, a change in wind speed, a rise in air temperature or a dip in ultraviolet light reaching the rover. Two of the events included all five characteristics.

In many regions of Mars, dust-devil tracks and shadows have been seen from orbit, but those visual clues have not been seen in Gale Crater. One possibility is that vortex whirlwinds arise at Gale without lifting as much dust as they do elsewhere.


This diagram illustrates Mars' "thermal tides," a weather phenomenon responsible for large, daily variations in pressure at the Martian surface. Image credit: NASA/JPL-Caltech/Ashima Research/SWRI.

"Dust in the atmosphere has a major role in shaping the climate on Mars," said Manuel de la Torre Juarez of NASA's Jet Propulsion Laboratory in Pasadena, Calif. He is the investigation scientist for REMS, which Spain provided for the mission. "The dust lifted by dust devils and dust storms warms the atmosphere."

Dominant wind direction identified by REMS has surprised some researchers who expected slope effects to produce north-south winds. The rover is just north of a mountain called Mount Sharp. If air movement up and down the mountain's slope governed wind direction, dominant winds generally would be north-south. However, east-west winds appear to predominate. The rim of Gale Crater may be a factor.

"With the crater rim slope to the north and Mount Sharp to the south, we may be seeing more of the wind blowing along the depression in between the two slopes, rather than up and down the slope of Mount Sharp," said Claire Newman, a REMS investigator at Ashima Research in Pasadena. "If we don't see a change in wind patterns as Curiosity heads up the slope of Mount Sharp -- that would be a surprise."

Mars Science Laboratory (MSL) description

REMS monitoring of air pressure has tracked both a seasonal increase and a daily rhythm. Neither was unexpected, but the details improve understanding of atmospheric cycles on present-day Mars, which helps with estimating how the cycles may have operated in the past.

The seasonal increase results from tons of carbon dioxide, which had been frozen into a southern winter ice cap, returning into the atmosphere as southern spring turns to summer. The daily cycle of higher pressure in the morning and lower pressure in the evening results from daytime heating of the atmosphere by the sun. As morning works its way westward around the planet, so does a wave of heat-expanded atmosphere, known as a thermal tide.

video
Wind and Radiation on Mars. Credit: NASA/JPL-Caltech

Effects of that atmospheric tide show up in data from Curiosity's Radiation Assessment Detector (RAD). This instrument monitors high-energy radiation considered to be a health risk to astronauts and a factor in whether microbes could survive on Mars' surface.

"We see a definite pattern related to the daily thermal tides of the atmosphere," said RAD Principal Investigator Don Hassler of the Southwest Research Institute's Boulder, Colo., branch. "The atmosphere provides a level of shielding, and so charged-particle radiation is less when the atmosphere is thicker. Overall, Mars' atmosphere reduces the radiation dose compared to what we saw during the flight to Mars."

The overall goal of NASA's Mars Science Laboratory mission is to use 10 instruments on Curiosity to assess whether areas inside Gale Crater ever offered a habitable environment for microbes.

JPL, a division of the California Institute of Technology in Pasadena, manages the project for NASA's Science Mission Directorate, Washington, and built Curiosity.

For more information about Curiosity and its mission, visit: http://www.nasa.gov/msl and http://mars.jpl.nasa.gov/msl .

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

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

Greetings, Orbiter.ch

Hubble helps find candidate for most distant object in the Universe yet observed












ESA - Hubble Space Telescope logo.

15 November 2012

 Hubble spots candidate for most distant known galaxy

By combining the power of the NASA/ESA Hubble Space Telescope, NASA’s Spitzer Space Telescope and one of nature’s zoom lenses, astronomers have found what is probably the most distant galaxy yet seen in the Universe. The object offers a peek back into a time when the Universe was only 3 percent of its present age of 13.7 billion years.

We see the newly discovered galaxy, named MACS0647-JD, as it was 420 million years after the Big Bang. Its light has travelled for 13.3 billion years to reach Earth, which corresponds to a redshift of approximately 11 [1].

Hubble spots three magnified views of most distant known galaxy

This is the latest discovery from the Cluster Lensing And Supernova survey with Hubble (CLASH) [2], which uses massive galaxy clusters as cosmic telescopes to magnify distant galaxies behind them, an effect called gravitational lensing.

“While one occasionally expects to find an extremely distant galaxy using the tremendous power of gravitational lensing, this latest discovery has outstripped even my expectations of what would be possible with the CLASH program,” said Rychard Bouwens (Leiden University, Netherlands), a co-author of the study. “The science output in this regard has been incredible.”

Galaxy cluster MACS J0647.7+7015

Along the way, 8 billion years into its journey, the galaxy’s light took a detour along multiple paths around the massive galaxy cluster MACS J0647.7+7015. Due to the gravitational lensing, the team observed three magnified images of MACS0647-JD with Hubble. The cluster’s gravity boosted the light from the faraway galaxy, making the images appear far brighter than they otherwise would, although they still appear as tiny dots in Hubble’s portrait.

“This cluster does what no manmade telescope can do,” said Marc Postman (Space Telescope Science Institute, USA), leader of the CLASH team. “Without the magnification, it would require a Herculean effort to observe this galaxy.”

The object is so small it may be in the first stages of galaxy formation, with analysis showing the galaxy is less than 600 light-years across. For comparison the Milky Way is 150 000 light-years across. The estimated mass of this baby galaxy is roughly equal to 100 million or a billion suns, or 0.1 - 1 percent the mass of our Milky Way’s stars.

video
Zoom on galaxy cluster MACS J0647.7+7015

“This object may be one of many building blocks of a galaxy,” explained Dan Coe (Space Telescope Science Institute), lead author of the study. “Over the next 13 billion years, it may have dozens, hundreds, or even thousands of merging events with other galaxies and galaxy fragments.”

The team spent months systematically ruling out all other alternative explanations for the object’s identity before concluding that it is the distance record holder. This was important, as nearby objects (such as red stars, brown dwarfs and old or dusty galaxies) can mimic the appearance of an extremely distant galaxy and must be carefully excluded.

The area around the galaxy was observed by Hubble through 17 filters — spanning near-ultraviolet to near-infrared wavelengths — with the galaxy appearing only in the two reddest filters. This was consistent with a highly redshifted galaxy, but did not fully exclude other possibilities. Images of the galaxy at longer infrared wavelengths taken by Spitzer were more conclusive, however: if the object were intrinsically red, it would appear bright in these images. Instead, the galaxy was barely detected, if at all.

MACS0647-JD may be too far away for any current telescope to confirm the distance with spectroscopy [3]. Nevertheless, all the evidence points towards the fledgling galaxy being the new distance record holder.

The galaxy will almost certainly be a prime target for the James Webb Space Telescope, scheduled for launch in 2018, which will be able to conduct spectroscopy to make a definitive measurement of its distance and study its properties in more detail.

Notes:

[1] Redshift is a consequence of the expansion of space over cosmic time, which stretches the wavelength of light. This has the consequence of making a distant object appear redder than it really is. Objects with a higher redshift have had their light stretched more, and are more distant. The previous candidate for the most distant object observed has a redshift of 10.3 (heic1103); confirmations of several objects with redshifts between 7 and 9 have been reported using spectroscopy, which gives more robust results (see for example eso1041). This newly discovered galaxy’s redshift has been calculated as being approximately 10.8, with a 95% confidence that it lies between 10.3 and 11.3.

[2] The new distance champion is the second remote galaxy uncovered in the CLASH survey, a multiwavelength census of 25 hefty galaxy clusters with Hubble's Advanced Camera for Surveys (ACS) and Wide Field Camera 3 (WFC3) instruments. Earlier this year, the CLASH team announced the discovery of a galaxy that existed when the universe was about 490 million years old (redshift 9.6), 70 million years later than the new record-breaking galaxy. So far, the survey has completed observations for 20 of the 25 clusters.

[3] Redshift can only be precisely measured using spectroscopy, in which an object’s light is dispersed and its colour probed in detail. However, it can be estimated by comparing images made of an object through different coloured filters, a method called photometric redshift. The galaxy will only be visible in some of the filters (having been redshifted out of some filters altogether), and the redshift is derived from the bluest filter in which the galaxy is visible. Photometric redshifts, as used in this study, provide less certainty, but they can be calculated for objects much fainter than is possible with spectroscopic redshifts. For this reason, the paper refers to the object as a 'candidate z≈11 galaxy'

More information:

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

The international team of astronomers in this study consists of:

Dan Coe (Space Telescope Science Institute, Baltimore, USA), Adi Zitrin (Institut für Theoretische Astrophysik, Heidelberg, Germany), Mauricio Carrasco (Institut für Theoretische Astrophysik, Heidelberg, Germany and Pontifica Universidad Católica de Chile, Santiago, Chile), Xinwen Shu (University of Science and Technology of China, Hefei, China), Wei Zheng (Johns Hopkins University, Baltimore, USA), Marc Postman (Space Telescope Science Institute, Baltimore, USA), Larry Bradley (Space Telescope Science Institute, Baltimore, USA), Anton Koekemoer (Space Telescope Science Institute, Baltimore, USA), Rychard Bouwens (Leiden University, Netherlands), Tom Broadhurst (University of the Basque Country, Bilbao, Spain and Ikerbasque Basque Foundation for Science, Bilbao, Spain) Anna Monna (Universitätssternwarter München, Munich, Germany), Ole Host (University College London, London, UK and Dark Cosmology Centre, Niels Bohr Institute, University of Copenhagen, Denmark), Leonidas A. Moustakas (Jet Propulsion Laboratory, California Institute of Technology, La Cañada Flintridge, USA), Holland Ford (Johns Hopkins University, Baltimore, USA), John Moustakas (Siena College, Loudonville, USA), Arjen van der Wel (Max Planck Institute for AStronomy, Heidelberg, Germany), Megan Donahue (Michigan State University, East Lansing, USA), Steven A. Rodney (Johns Hopkins University, Baltimore, USA), Narciso Bentez (Instituto de Astrofísica de Andalucía, Granada, Spain), Stephanie Jouvel (University College London, London, UK and Institut de Cincies de l’Espai, Bellaterra (Barcelona), Spain), Stella Seitz (Universitätssternwarte München, Munich, Germany and Max Planck Institute for Extraterrestrial Physics, Garching, Germany), Daniel D. Kelson (Carnegie Observatories, Pasadena, USA), and Piero Rosati (European Southern Observatory, Garching, Germany)

The research is presented in a paper entitled “CLASH: Three Strongly Lensed Images of a Candidate z≈11 Galaxy” to be published in the December 20 issue of the Astrophysical Journal.

Links:
    Images of Hubble: http://www.spacetelescope.org/images/archive/category/spacecraft/

    NASA press release: http://hubblesite.org/news/2012/36

    CLASH collaboration: http://www.stsci.edu/~postman/CLASH/

    Research paper: http://www.spacetelescope.org/static/archives/releases/science_papers/heic1217.pdf

Images, Text, Credits: NASA, ESA, and M. Postman and D. Coe (Space Telescope Science Institute), and the CLASH team / Video: NASA, ESA, G. Bacon.

Best regards, Orbiter.ch

Born-again star foreshadows fate of Solar System














ESA - Hubble Space Telescope logo / ESA - XMM-Newton Mission patch.

15 November 2012

 Abell 30: a born-again planetary nebula

Astronomers have found evidence for a dying Sun-like star coming briefly back to life after casting its gassy shells out into space, mimicking the possible fate our own Solar System faces in a few billion years.

This new picture of the planetary nebula Abell 30, located 5500 light-years from Earth, is a composite of visible images from the NASA/ESA Hubble Space Telescope and X-ray data from ESA’s XMM-Newton and NASA’s Chandra space telescopes.

‘Planetary nebula’ is the name given to the often-concentric shells of stellar material cast into space by dying stars. To astronomers of the 18th century, these objects looked like the colourful ‘blob’ of a planet through their telescopes, and the name stuck.

Astronomers now know that as a star with less than eight times the mass of the Sun swells into a red giant towards the end of its life, its outer layers are expelled via pulsations and winds.

Ultraviolet radiation shining out from the stripped-down hot stellar core then lights up the ejected shells, resulting in intricate artworks that can be seen by modern telescopes.

The star at the heart of Abell 30 experienced its first brush with death
12 500 years ago – as seen from Earth – when its outer shell was stripped off by a slow and dense stellar wind.

ESA / NASA Hubble Space Telescope in orbit

Optical telescopes see the remnant of this evolutionary stage as a large, near-spherical shell of glowing material expanding out into space.

Then, about 850 years ago, the star suddenly came back to life, coughing out knots of helium and carbon-rich material in a violent event.

The star’s outer envelope briefly expanded during this born-again episode, but then very rapidly contracted again witin 20 years.

This had the knock-on effect of accelerating the wind from the star to its present speed of 4000 kilometres per second – over 14 million kilometres per hour.

As this fast stellar wind catches up and interacts with the slower wind and clumps of previously ejected material, complex structures are formed, including the delicate comet-like tails seen near the central star in this image.

ESA XMM-Newton in orbit

The stellar wind bombarding dense clumps of material provides a chilling look at the possible fate of Earth and its fellow planets in our own Solar System in a few billion years’ time.

When our Sun emits its final gasps of life at the heart of a planetary nebula, its strong stellar wind and harsh radiation will blast and evaporate any planets that may have survived the red giant phase of stellar evolution.

If any distant civilisation is watching with high-power telescopes at the time, they might see the glowing embers of the planets light up in X-rays as they are engulfed in the stellar wind. 

Related links:

Hubble's Universe: http://spacetelescope.org/

Hubble overview: http://www.esa.int/esaSC/SEM106WO4HD_index_0_m.html

Hubble in depth: http://sci.esa.int/science-e/www/area/index.cfm?fareaid=31

XMM-Newton overview: http://www.esa.int/esaSC/120385_index_0_m.html

XMM-Newton factsheet: http://www.esa.int/esaSC/SEM14YS1VED_index_0.html

XMM-Newton in-depth: http://sci.esa.int/science-e/www/area/index.cfm?fareaid=23

Chandra at NASA: http://chandra.nasa.gov/

Chandra at Harvard: http://chandra.harvard.edu/

Images, Text. Credits: Main image: X-ray: ESA/XMM-Newton; optical: NSF/NOAO/KPNO; inset: NASA/CXC/IAA-CSIC/M. Guerrero et al; optical: NASA/STScI.

Greetings, Orbiter.ch

mercredi 14 novembre 2012

Life and death in a star-forming cloud














ESA - Herschel Mission patch / ESA - XMM-Newton Mission patch.

14 November 2012

The aftershock of a stellar explosion rippling through space is captured in this new view of supernova remnant W44, which combines far-infrared and X-ray data from ESA’s Herschel and XMM-Newton space observatories.

W44, located around 10 000 light-years away within a forest of dense star-forming clouds in the constellation of Aquila, the Eagle, is one of the best examples of a supernova remnant interacting with its parent molecular cloud.

W44 and its environment

The product of a massive star that has already reached the end of its life and expelled its outer layers in a dramatic explosion, all that remains of the stellar behemoth is the spinning core of a neutron star, or pulsar.

Identified as PSR B1853+01, the pulsar is the bright point to the top left in W44, coloured light blue in this image. 

It is thought to be around 20 000 years old and as it rapidly rotates it sweeps out a wind of highly energetic particles and beams of light ranging from radio to X-ray energies.

W44 in the far-infrared

The centre of the supernova remnant is also bright in X-rays, coming from the hot gas that fills the shell, at temperatures of several million degrees. Dense knots of high-energy emission reflect regions where heavier elements are more commonly found.

At the cooler edge of the cavity, gas is swept up as the supernova remnant propagates through space.

At the top right of the expanding shell, there is a smaller cavity, with the shock from the supernova remnant impacting the bight arc-shaped feature. This region is filled with hot gas that has been ionised by the intense ultraviolet radiation from embedded young massive stars.

W44 in X-rays

Herschel’s far-infrared eyes can also seek out regions of gently heated gas and dust further from W44, where new stars are congregating.

Examples include the arrowhead-shaped star-formation region to the right of W44, which appears to point to another trio of intricate clouds further to the right and above.

Annotated image of  W44

More broadly, a number of compact objects scattered across the scene map the cold seeds of future stars that will eventually emerge from their dusty cocoons.

Finally, diffuse purple emission towards the bottom left of the image provides a glimpse of the Galactic plane.

Related links:

Herschel: ESA's giant infrared observatory: http://www.esa.int/SPECIALS/Herschel/index.html

More about:

Herschel overview: http://www.esa.int/SPECIALS/Herschel/index.html

Online Showcase of Herschel Images OSHI: http://oshi.esa.int/

XMM-Newton overview: http://www.esa.int/esaSC/120385_index_0_m.html

Read more:
Observations: Seeing in infrared wavelengths: http://www.esa.int/esaSC/SEMS72T1VED_index_0.html

Why infrared astronomy is a hot topic: http://www.esa.int/esaSC/SEMX9PZO4HD_index_0.html

Images, Text, Credits: Herschel: Q. Nguyen Luong & F. Motte, HOBYS Key Program consortium, Herschel SPIRE/PACS/ESA consortia. XMM-Newton: ESA/XMM-Newton.

Best regards, Orbiter.ch

NASA's Kepler Completes Prime Mission, Begins Extended Mission












NASA - Kepler Mission patch.

Nov. 14, 2012

 (Click image for full resolution)

The timeline series includes a compilation of artist's concepts depicting milestones from the Kepler mission—NASA's first mission capable of detecting Earth-size planets around sun-like stars. Milestones include launch of the space telescope, the first transiting planetary system, the smallest planet with both radius and mass measurements, the first six-planet system, the first double-star planet, the smallest planet in the habitable zone of a star similar to our sun.
Image credit: NASA Ames Research Center/W. Stenzel.

NASA is marking two milestones in the search for planets like Earth -- the successful completion of the Kepler Space Telescope's 3 1/2- year prime mission and the beginning of an extended mission that could last as long as four years.

Scientists have used Kepler data to identify more than 2,300 planet candidates and confirm more than 100 planets – teaching us that the galaxy is teeming with planetary systems, that planets are prolific, and hints that nature makes small planets efficiently.

So far, hundreds of Earth-size planet candidates have been found as well as candidates that orbit in the habitable zone, the region in a planetary system where liquid water might exist on the surface of a planet. None of the candidates is exactly like Earth. With the completion of the prime mission, Kepler has now collected enough data to begin finding true sun-Earth analogs -- Earth-size planets with a one-year orbit around stars similar to the sun.

"The initial discoveries of the Kepler mission indicate that at least a third of the stars have planets and that the number of planets in our galaxy must number in the billions," said William Borucki, Kepler principal investigator at NASA's Ames Research Center in Moffett Field, Calif. "The planets of greatest interest are other Earths and these could already be in the data awaiting analysis. Kepler’s most exciting results are yet to come!"

NASA's Kepler Space Telescope searches for planet candidates orbiting distant suns, or exoplanets, by continuously measuring the brightness of more than 150,000 stars. When a planet candidate passes, or transits, in front of the star from the spacecraft's vantage point, light from the star is blocked. Different sized planets block different amounts of starlight. The amount of starlight blocked by a planet reveals its size relative to its star.

Kepler was launched March 6, 2009. Its mission was to survey a portion of the galaxy to determine what fraction of stars might harbor potentially habitable, Earth-sized planets. Planets orbiting in or near habitable zones are of particular interest.

Artist concept of Kepler in space. Image credit: NASA

Kepler began the search for small worlds like our own on May 12, 2009, after two months of commissioning. Within months, five exoplanets, known as hot Jupiters because of their enormous size and orbits close to their stars, were confirmed.

Kepler's exquisitely precise photometer, or light sensor, is designed to detect minute changes in brightness, to indicate an Earth-size planet. For a remote observer, Earth transiting the sun would dim its light by only 84 parts per million. That is less than 1/100th of one percent, or the equivalent of the amount of light blocked by a gnat crawling across a car’s headlight viewed from several miles away.

Transit data are rich with information. By measuring the depth of the dip in brightness and knowing the size of the star, scientists can determine the size or radius of the planet. The time the planet takes to orbit can be determined by measuring the elapsed time between transits. Once the period is known, Kepler's Third Law of Planetary Motion can be applied to determine the average distance of the planet from its star. Using this distance, and the temperature and size of the star, scientists can determine if the planet is in the habitable zone.

Results from Kepler data continue to expand our understanding of planets and planetary systems. Highlights from the prime mission include:

  • In August 2010, scientists confirmed the discovery of the first planetary system with more than one planet transiting the same star. The Kepler-9 system opened the door allowing the measurement of gravitational interactions between planets as observed by the variations in their transit timing. This powerful new technique enables astronomers, in many cases, to calculate the mass of planets directly from Kepler data, without the need of follow-up ground-based observations.

  • In January 2011, the Kepler team announced the discovery of the first unquestionably rocky planet outside the solar system. Measuring 1.4 times the size of Earth, Kepler-10b is the smallest confirmed planet with both a radius and mass measurement. Results from Kepler data have continued to uncover smaller and smaller planets, some nearly the size of Mars, and tell us that small rocky worlds may be common in the galaxy.

  • In February 2011, scientists announced it had found a very crowded and compact planetary system- a star with multiple transiting planets. Kepler-11 has six planets larger than Earth, all orbiting closer to their star than Venus orbits the sun. This and other subsequently identified compact multi-planet systems have orbital spacing relative to their host sun and neighboring planets unlike anything envisioned prior to the mission.

  • In September 2011, Kepler data confirmed the existence of a world with a double sunset like the one famously portrayed in the film Star Wars more than 35 years ago. The discovery of Kepler-16b made what once was the realm of science fiction, science fact. Since then, the discoveries of six additional worlds orbiting double stars further demonstrate that planets can form and persist in the environs of a double-star system.

  • In December 2011, Kepler announced the mission's first planet in the habitable zone. At approximately 2.4 times the size of Earth, Kepler-22b is the smallest radius planet yet found to orbit a sun-like star in the habitable zone. This discovery confirmed that we are getting continually closer to finding planets like our own.

  • In February 2012, the Kepler team announced more than 1,000 new transiting planet candidates for a cumulative total of 2,321. The data continues the trend toward identifying smaller planets at longer orbital periods, similar to Earth. The results include hundreds of planetary systems– stars with multiple transiting planet candidates.

  • Recently, citizen scientists participating in Planets Hunters, a Yale-led program that enlists the public to comb through Kepler data for signs of transiting planets, made their first planet discovery. The joint effort of amateur astronomers and scientists led to the first reported case of a planet orbiting a double-star that, in turn, are orbited by a second distant pair of stars.
"Kepler's bounty of new planet discoveries, many quite different from anything found previously, will continue to astound. But to me, the most wonderful discovery of the mission has not been individual planets, but the systems of two, three, even six planets crowded close to their stars, and, like the planets orbiting about our sun, moving in nearly the same plane," said Jack Lissauer, planetary scientist at Ames. "Like people, planets interact with and can be greatly affected by their neighbors. What are the neighborhoods of Earth-size exoplanets like? This is the question that I most hope Kepler will answer in the years to come."

In April 2012, NASA awarded Kepler an extended mission, through as late as 2016. More time will enable the continued search for worlds like our own -- worlds that are not too far and too close to their sun.

"The Earth isn't unique, nor the center of the universe. The diversity of other worlds is greater than depicted in all the science fiction novels and movies," said Geoff Marcy, professor of astronomy at the University of California, Berkeley. "Aristotle would be proud of us for answering some of the most profound philosophical questions about our place in the universe."

Ames manages Kepler's ground system development, mission operations and science data analysis. NASA's Jet Propulsion Laboratory in Pasadena, Calif., managed the Kepler mission development.

Ball Aerospace & Technologies Corp. in Boulder, Colo., developed the Kepler flight system and supports mission operations with the Laboratory for Atmospheric and Space Physics at the University of Colorado in Boulder.

The Space Telescope Science Institute in Baltimore archives, hosts and distributes Kepler science data. Kepler is NASA's 10th Discovery Mission and funded by NASA's Science Mission Directorate at the agency's headquarters in Washington.

For more information about the Kepler mission, visit: http://www.nasa.gov/kepler

Images (mentioned), Text, Credits: NASA / Ames Research Center / Michele Johnson.

Cheers, Orbiter.ch

Rover's 'SAM' Lab Instrument Suite Tastes Soil












NASA - Mars Science Laboratory (MSL) patch.

Nov. 14, 2012

A pinch of fine sand and dust became the first solid Martian sample deposited into the biggest instrument on NASA's Mars rover Curiosity: the Sample Analysis at Mars, or SAM.

Located inside the rover, SAM examines the chemistry of samples it ingests, checking particularly for chemistry relevant to whether an environment can support life. Curiosity's robotic arm delivered SAM's first taste of Martian soil to an inlet port on the rover deck on Nov. 9. During the following two days, SAM used mass spectrometry, gas chromatography and laser spectrometry to analyze the sample.

The sample came from the patch of windblown material called "Rocknest," which had provided a sample previously for mineralogical analysis by Curiosity's Chemistry and Mineralogy (CheMin) instrument. CheMin also received a new sample from the same Rocknest scoop that fed SAM. SAM has previously analyzed samples of the Martian atmosphere.


Image above: This subframe image from the left Mast Camera (Mastcam) on NASA's Mars rover Curiosity shows the covers in place over two sample inlet funnels of the rover's Sample Analysis at Mars (SAM) instrument suite. Image credit: NASA/JPL-Caltech/MSSS.

"We received good data from this first solid sample," said SAM Principal Investigator Paul Mahaffy of NASA Goddard Space Flight Center, Greenbelt, Md. "We have a lot of data analysis to do, and we are planning to get additional samples of Rocknest material to add confidence about what we learn."

The SAM Suite


Images above: The Sample Analysis at Mars (SAM) instrument, largest of the 10 science instruments for NASA's Mars Science Laboratory mission, examines samples of Martian rocks, soil and atmosphere for information about chemicals that are important to life and other chemical indicators about past and present environments.

SAM is in fact a suite of three different instruments supported by a complex set of components to process gases and solids. The instruments are: Quadrupole Mass Spectrometer (QMS), Tunable Laser Spectrometer (TLS), and Gas Chromatograph (GC).

Other components include: a sample manipulation system (SMS) with 74 cups; two solid sample inlet tubes (SSIT); two turbomolecular wide-range pumps (WRP); two ovens to release gas to SAM's instruments; 14 gas processing manifolds; two high conductance valves; 52 micro-valves; 51 gas line heaters; combustion and calibration gases; two scrubbers and two getters; four hydrocarbon traps; two helium tanks; four reflux heat pipes; an electronics stack consisting of eight separate modules; about 20 feet (600 meters) of harness wire; two gas inlets; and two vents to Curiosity's exterior.

The SAM instrument was developed at NASA Goddard Space Flight Center, Greenbelt, Md., with instrument contributions from NASA's Jet Propulsion Laboratory in Pasadena, Calif., and the University of Paris, France, collaborators. Image credit: NASA/JPL-Caltech.

Potential Sources and Sinks of Methane on Mars


Illustration above: If the atmosphere of Mars contains methane, various possibilities have been proposed for where the methane could come from and how it could disappear.

Potential non-biological sources for methane on Mars include comets, degradation of interplanetary dust particles by ultraviolet light, and interaction between water and rock. A potential biological source would be microbes, if microbes have ever lived on Mars. Potential sinks for removing methane from the atmosphere are photochemistry in the atmosphere and loss of methane to the surface. Image credit: NASA/JPL-Caltech, SAM/GSFC.

Volatiles on Mars


This illustration shows the locations and interactions of volatiles on Mars. Volatiles are molecules that readily evaporate, converting to their gaseous form, such as water and carbon dioxide. On Mars, and other planets, these molecules are released from the crust and planetary interior into the atmosphere via volcanic plumes. On Mars, significant amounts of carbon dioxide go back and forth between polar ice caps and the atmosphere depending on the season (when it's colder, this gas freezes into the polar ice caps).

New results from the Sample Analysis at Mars, or SAM, instrument on NASA's Curiosity rover show that the lighter forms of certain volatiles, also called isotopes, have preferentially escaped from the atmosphere, leaving behind a larger proportion of heavy isotopes. Scientists will continue to examine this phenomenon as the mission continues, looking for isotope signatures in rocks. One question they plan to address is: To what degree have atmospheric volatiles been incorporated into rocks in the crust through the action of fluids, perhaps in the distant past? Image credit: NASA/JPL-Caltech.


Image above: High-Resolution Self-Portrait by Curiosity Rover Arm Camera. Image Credit: NASA/JPL-Caltech/Malin Space Science Systems.

NASA's Jet Propulsion Laboratory, a division of the California Institute of Technology, Pasadena, manages the Mars Science Laboratory Project for NASA's Science Mission Directorate, Washington. JPL designed and built the rover.

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 (mentioned), Text, Credits: NASA / Jet Propulsion Laboratory / Guy Webster.

Best regards, Orbiter.ch

Long-Lived Orbiter Resumes Work With Fresh Equipment











NASA - 2001 Mars Odyssey patch.

Nov. 14, 2012

Mission Status Report

The NASA Mars Odyssey orbiter has resumed duty after switching to a set of redundant equipment, including a main computer, that had not been used since before the spacecraft's 2001 launch.

Odyssey relayed data to Earth late Sunday that it received from NASA's Opportunity rover on Mars using the orbiter's fresh "B-side" radio for UHF (ultra-high frequency) communications. In plans for this week are relay opportunities for the newest Mars rover, Curiosity, and resumption of Odyssey's own scientific observations.

"The side-swap has gone well. All the subsystems that we are using for the first time are performing as intended," said Odyssey Project Manager Gaylon McSmith of NASA's Jet Propulsion Laboratory, Pasadena, Calif.

Artist concept of Mars Odyssey. Image credit: NASA/JPL

Like many spacecraft, this orbiter carries a pair of redundant main computers, to have a backup available if one fails. Odyssey's A-side computer and B-side computer each have several other redundant subsystems linked to just that computer.

Odyssey is already the longest-working spacecraft ever sent to Mars. The side swap was initiated last week in response to months of diagnostic data indicating that the A side's inertial measurement unit shows signs of wearing out. This gyroscope-containing mechanism senses changes in the spacecraft's orientation, providing important information for control of pointing the antenna, solar arrays and instruments.

The diagnostics indicate that the A side's inertial measurement unit still has a few months or more of useful life. The reason for switching sides was to keep a fully functional A side available in case of any problem on the B side in coming years that can be dealt with by switching back to the A side temporarily for a few days or weeks.

"It is testimony to the excellent design of this spacecraft and operation of this mission in partnership with Lockheed Martin that we have brand-new major components available to begin using after more than 11 years at Mars," McSmith said.

JPL, a division of the California Institute of Technology in Pasadena, manages the Mars Odyssey project for NASA's Science Mission Directorate in Washington. Lockheed Martin Space Systems in Denver built the spacecraft. JPL and Lockheed Martin collaborate on operating the spacecraft.

The Mars Reconnaissance Orbiter, which shares with Odyssey the data-relay responsibility for NASA's Mars rovers, continued relay support while Odyssey was unavailable for a few days following the side swap.

Odyssey launched April 7, 2001, began orbiting Mars Oct. 24 that year, began systematic science observations of Mars in early 2002, and broke the previous record for longest-working Mars spacecraft in December 2010. Odyssey's longevity enables continued science by instruments on the orbiter, including the monitoring of seasonal changes on Mars from year to year, in addition to communication-relay service. For more about the Mars Odyssey mission, visit: http://mars.jpl.nasa.gov/odyssey .

Image (mentioned), Text, Credits: NASA / Jet Propulsion Laboratory / Guy Webster.

Best regards, Orbiter.ch

Spacecraft Meridian launched into the target orbit









ROSCOSMOS "FKA" logo.

11/14/2012

November 14 at 15 hours 42 minutes MSK from Launch Complex 43 site Plesetsk State Test joint calculation Forces aerospace defense and enterprise space industry the launch of a space rocket Soyuz-2.1a with the upper stage Fregat and spacecraft (SC) for the Ministry of Defence of the Russian Federation.

Soyuz-2.1a launch

The estimated time of the spacecraft launched into the target orbit and adopted by the management.

For SC injection into orbit used rocket Soyuz-2.1a (the leading developer and manufacturer - HNP RCC TsSKB Progress, Samara) and the upper stage Fregat, developed at the FSUE NPO. Lavochkin.

Meridian satellite

The spacecraft is manufactured by JSC ISS Academician Reshetnev (Zheleznogorsk) for assignments on behalf of the Ministry of Defense of the Russian Federation and connecting vessels and aircraft ice patrol in the North Sea route to coastal land stations as well as satellite communications northern regions of Siberia and the Far East.

The series of launches will replace Russia’s ageing Molniya guidance system. The country has almost 100 satellites in orbit. Most of them serve military or dual purposes.

Original text in Russian: http://www.federalspace.ru/main.php?id=2&nid=19689

Images, Text, Credits: Press Service of the Russian Federal Space Agency (Roscosmos PAO) / Translation: Orbiter.ch.

Greetings, Orbiter.ch

Russia without contact with its satellites and the ISS












ROSCOSMOS logo.

November 14, 2012

Spatial linkages Control Center for flights with Russian satellites are interrupted due to a cable break.

Operations undocking of a Soyuz spacecraft could be disrupted by the incident (photo: Space ISS)

Russia has lost touch with its satellites and can send commands to the International Space Station due to a cable break in the Moscow region, said Wednesday industry sources cited by the space agencies of Russia.

"A cable was broken, and the flight control center (Tsoup near Moscow, ed) is a private communication," said one of the sources to the Interfax news agency.

"Our specialists have the possibility to remotely control civilian satellites or the Russian segment of the International Space Station (ISS) crew and they are able to communicate with him, but can not send commands to the Russian segment" , said a source indicated to the public agency, Ria Novosti.

Impact

A source quoted by the same agency also said that this incident could have prevented the preparation of a Soyuz undocking must return to Earth three crew members of the ISS, scheduled for November 19.

The Russian space agency Roscosmos has required much more reassuring, saying that "redistribution" means ground control was underway.

"The failure of a cable at work (the Moscow region) does not affect the functioning of the Russian spacecraft and the International Space Station," said Alexei Kuznetsov, a head of Roscosmos, Interfax .

Image, Text, Credits: AFP / Space ISS / Translation: Orbiter.ch.

Greetings, Orbiter.ch

Lost in Space: Rogue Planet Spotted?












ESO - European Southern Observatory logo.

14 November 2012

Orphaned world may help to explain how planets and stars form

Artist’s impression of the free-floating planet CFBDSIR J214947.2-040308.9

Astronomers using ESO’s Very Large Telescope and the Canada-France-Hawaii Telescope have identified a body that is very probably a planet wandering through space without a parent star. This is the most exciting free-floating planet candidate so far and the closest such object to the Solar System at a distance of about 100 light-years. Its comparative proximity, and the absence of a bright star very close to it, has allowed the team to study its atmosphere in great detail. This object also gives astronomers a preview of the exoplanets that future instruments aim to image around stars other than the Sun.

Free-floating planets are planetary-mass objects that roam through space without any ties to a star. Possible examples of such objects have been found before [1], but without knowing their ages, it was not possible for astronomers to know whether they were really planets or brown dwarfs — “failed” stars that lack the bulk to trigger the reactions that make stars shine.

The free-floating planet CFBDSIR J214947.2-040308.9

But astronomers have now discovered an object, labelled CFBDSIR2149 [2], that seems to be part of a nearby stream of young stars known as the AB Doradus Moving Group. The researchers found the object in observations from the Canada-France-Hawaii Telescope and harnessed the power of ESO’s Very Large Telescope to examine its properties [3].

The AB Doradus Moving Group is the closest such group to the Solar System. Its stars drift through space together and are thought to have formed at the same time. If the object is associated with this moving group — and hence it is a young object — it is possible to deduce much more about it, including its temperature, mass, and what its atmosphere is made of [4]. There remains a small probability that the association with the moving group is by chance.

The free-floating planet CFBDSIR J214947.2-040308.9 (annotated)

The link between the new object and the moving group is the vital clue that allows astronomers to find the age of the newly discovered object [5]. This is the first isolated planetary mass object ever identified in a moving group, and the association with this group makes it the most interesting free-floating planet candidate identified so far.

“Looking for planets around their stars is akin to studying a firefly sitting one centimetre away from a distant, powerful car headlight,” says Philippe Delorme (Institut de planétologie et d’astrophysique de Grenoble, CNRS/Université Joseph Fourier, France), lead author of the new study. “This nearby free-floating object offered the opportunity to study the firefly in detail without the dazzling lights of the car messing everything up.”

The free-floating planet CFBDSIR J214947.2-040308.9

Free-floating objects like CFBDSIR2149 are thought to form either as normal planets that have been booted out of their home systems, or as lone objects like the smallest stars or brown dwarfs. In either case these objects are intriguing — either as planets without stars, or as the tiniest possible objects in a range spanning from the most massive stars to the smallest brown dwarfs.

“These objects are important, as they can either help us understand more about how planets may be ejected from planetary systems, or how very light objects can arise from the star formation process,” says Philippe Delorme. “If this little object is a planet that has been ejected from its native system, it conjures up the striking image of orphaned worlds, drifting in the emptiness of space.”

video
Artist's impression of the free-floating planet CFBDSIR J214947.2-040308.9

These worlds could be common — perhaps as numerous as normal stars [6]. If CFBDSIR2149 is not associated with the AB Doradus Moving Group it is trickier to be sure of its nature and properties, and it may instead be characterised as a small brown dwarf. Both scenarios represent important questions about how planets and stars form and behave.

“Further work should confirm CFBDSIR2149 as a free-floating planet,” concludes Philippe Delorme. “This object could be used as a benchmark for understanding the physics of any similar exoplanets that are discovered by future special high-contrast imaging systems, including the SPHERE instrument that will be installed on the VLT.”

Notes:

[1] Numerous candidates for these kinds of planets have been found before (with corresponding press releases and papers, e.g. from Science Magazine, Nature, Royal Astronomical Society). These objects started to become known in the 1990s, when astronomers found that the point at which a brown dwarf crosses over into the planetary mass range is difficult to determine. More recent studies have suggested that there may be huge numbers of these little bodies in our galaxy, a population numbering almost twice as many as the main sequence stars present.

[2] The object was identified as part of an infrared extension of the Canada-France Brown Dwarfs Survey (CFBDS), a project hunting for cool brown dwarf stars. It is also referred to as CFBDSIR J214947.2-040308.9.

[3] The team observed CFBDSIR2149 with both the WIRCam camera on the Canada France Hawaii Telescope on Hawaii, and the SOFI camera on the ESO New Technology Telescope in Chile. The images taken at different times allowed the object’s proper motion across the sky to be measured and compared to members of the AB Doradus Moving Group. The detailed study of the object’s atmosphere was made using the X-shooter spectrograph on ESO’s Very Large Telescope at the Paranal Observatory.

[4] The association with the AB Doradus Moving Group would pin down the mass of the planet to approximately 4–7 times the mass of Jupiter, with an effective temperature of approximately 430 degrees Celsius. The planet’s age would be the same as the moving group itself — 50 to 120 million years.

[5] The team’s statistical analysis of the object’s proper motion — its angular change in position across the sky each year — shows an 87% probability that the object is associated with the AB Doradus Moving Group, and more than 95% probability that it is young enough to be of planetary mass, making it much more likely to be a rogue planet rather than a small “failed” star. More distant free-floating planet candidates have been found before in very young star clusters, but could not be studied in detail.

[6] These free-floating objects can also reveal their presence when they pass in front of a star. The light travelling towards us from the background star is bent and distorted by the gravity of the object, causing the star to suddenly and briefly brighten — a process known as gravitational microlensing. Microlensing surveys of the Milky Way, such as OGLE, may have detected free-floating planets in this way (for example, a Microlensing Experiment published in Nature in 2011).

More information:

This research is presented in a paper, “CFBDSIR2149-0403: a 4-7 Jupiter-mass free-floating planet in the young moving group AB Doradus?” to appear in Astronomy & Astrophysics on 14 November 2012.

The team is composed of P. Delorme (Institut de planétologie et d’astrophysique de Grenoble, CNRS/Université Joseph Fourier, France [IPAG]), J. Gagné (Université de Montréal, Canada), L. Malo (Université de Montréal, Canada), C. Reylé (Institut UTINAM, CNRS/OSU THETA Franche-Comté-Bourgogne/Université de Franche Comté, France), E. Artigau (Université de Montréal, Canada), L. Albert (Université de Montréal, Canada), T. Forveille (Institut de planétologie et d’astrophysique de Grenoble, CNRS/Université Joseph Fourier, France [IPAG]), X. Delfosse (Institut de planétologie et d’astrophysique de Grenoble, CNRS/Université Joseph Fourier, France [IPAG]), F. Allard (Université Claude Bernard Lyon 1, France), D. Homeier (Université Claude Bernard Lyon 1, France).

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 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”.

The Canada-France-Hawaii Telescope (CFHT) is operated by the National Research Council of Canada, the Institut National des Sciences de l'Univers of the Centre National de la Recherche Scientifique of France, and the University of Hawaii.

Links:

Research paper: http://www.eso.org/public/archives/releases/sciencepapers/eso1245/eso1245a.pdf

Photos of the VLT: http://www.eso.org/public/images/archive/category/paranal/

More information about SPHERE: http://www.eso.org/sci/facilities/develop/instruments/sphere.html

Science Magazine: http://www.sciencemag.org/content/290/5489/103.abstract

Nature: http://www.nature.com/nature/journal/v473/n7347/full/nature10092.html

Royal Astronomical Society: http://www.ras.org.uk/news-and-press/71-news2001/405-pn01-12-nam5

Images, Video, Text, Credits: ESO / L. Calçada / P. Delorme / Nick Risinger (skysurvey.org) / R. Saito / VVV Consortium.

Best regards, Orbiter.ch

Proba-2 soaks up three solar eclipses







ESA - Proba-2 Mission logo.

14 November 2012

ESA’s Sun-watching Proba-2 satellite experienced three partial solar eclipses last night while lucky observers watching from northern Australia were treated to a total solar eclipse.

During a total solar eclipse, the Moon moves in front of the Sun as seen from Earth, their alignment and separation such that the much closer Moon appears large enough to temporarily block out the light from the much more distant Sun.

Totality

Since Proba-2 orbits the Earth about 14.5 times per day, it can dip in and out of the Moon’s shadow around the time of a solar eclipse. The constant change in viewing angle of Proba-2 meant that the satellite passed through the Moon’s shadow a total of three times during the eclipse yesterday, as shown in the video presented here.

As the Sun was never completely covered up from Proba-2’s vantage point, each eclipse was only partial. 

video
Proba-2 sees three partial solar eclipses

The video was produced from images taken by Proba-2’s SWAP imager, which snaps the Sun in ultraviolet light. Stormy active regions on the Sun’s face are revealed, including sunspots, the roots of some large solar flares and coronal mass ejections that are occasionally directed towards Earth.

The apparent noise in the movie results from high energy particles hitting Proba-2's electronics as the spacecraft passes through the South Atlantic Anomaly. The dimming in the movie is an effect as part of the satellite's orbit passes through the shadow of the Earth.

At the time of the total eclipse as seen from the ground, Proba-2 saw the full disc of the Sun.

“The satellite also spent hours collecting data of the solar environment further away from the Sun before and after the main eclipse event, providing context for the ground-based observations,” said Joe Zender, Proba-2 mission manager.

Observing in visible light extremely close to the solar surface is only possible from the ground during eclipses when the bright solar disc is temporarily obscured, briefly exposing the Sun’s bright atmosphere, or corona, and the red glow of the chromosphere.

“Combining visible light observations with the extreme ultraviolet images from Proba-2 gives us a unique opportunity to access difficult-to-see regions of the Sun at different wavelengths, during a rare event such as a total solar eclipse,” added Zender.

Partial solar eclipse

Observers on the ground watched in awe as darkness swept across the land for a little over 2 minutes. Proba-2 scientist Anik De Groof watched the event with thousands of others along the Australian coast at Palm Cove.

“We got all a bit nervous when after sunrise the partially eclipsed Sun was covered by a big cloud, but 5 minutes before totality, the cloud dissolved and we could watch ‘Baily’s beads’ form – the effect where beads of sunlight shine through the rugged lunar landscape,” said De Groof.

“At totality we could see the red chromosphere and the corona in the most beautiful conditions – it was fantastic!”

Australians will have another chance to see a solar eclipse in May 2013, although because the Moon will be slightly further away from the Earth, it won’t block the whole Sun, resulting in an ‘annular eclipse’. Europe will have to wait until November 2013 before the opportunity arises to see a partial solar eclipse across much of the south.

Proba-2 in orbit rear view

Meanwhile, ESA’s fleet of Sun-watching spacecraft will continue to monitor the Sun’s stormy behaviour as it unleashes its plasma load out into space and towards Earth. Scientists will get even closer to the action in 2017 with the launch of Solar Orbiter, which will travel to observe the Sun from a daring distance of just 42 million kilometres, inside the orbit of planet Mercury.

More about...

Proba-2: http://www.esa.int/SPECIALS/Proba/SEMJJ5ZVNUF_0.html

Image, Video, Text, Credits: ESA / Proba-2 Consortium / Anik De Groof.

Greetings, Orbiter.ch

mardi 13 novembre 2012

LHCb presents evidence of rare B decay












CERN - European Organization for Nuclear Research logo.

13 November 2012


Image above: A beam of protons enters the LHCb detector on the left, creating a B0s particle, which decays into two muons (purple tracks crossing the whole detector). (Image: LHCb/CERN).

Today at the Hadron Collider Physics Symposium in Kyoto, Japan, the Large Hadron Collider beauty (LHCb) collaboration presented evidence for one of the rarest particle decays ever observed.

The Standard Model of particle physics predicts that the B0S particle, which is made of a bottom antiquark bound to a strange quark, should decay into a pair of muons (μμ) about 3 times in every billion (109) decays. LHCb's measurement, from an analysis of data from 2011 and part of that from 2012, gives a value of (3.2+1.5-1.2) × 10-9.  LHCb spokesperson Pierluigi Campana told the CERN Bulletin that the value is "in very good agreement with the prediction."

Particle physicists describe the certainty of a result on a scale that goes up to 5 sigma. One sigma could be a random statistical fluctuation in the data, 3 sigma counts as evidence, but only a full 5-sigma result is a discovery. The significance of the LHCb measurement is 3.5 sigma and therefore is classified as the first evidence for the B0s →μμ decay.

 CERN LHC - To discover the secrets of the Universe

Note:

CERN, the European Organization for Nuclear Research, is one of the world’s largest and most respected centres for scientific research. Its business is fundamental physics, finding out what the Universe is made of and how it works. At CERN, the world’s largest and most complex scientific instruments are used to study the basic constituents of matter — the fundamental particles. By studying what happens when these particles collide, physicists learn about the laws of Nature.

The instruments used at CERN are particle accelerators and detectors. Accelerators boost beams of particles to high energies before they are made to collide with each other or with stationary targets. Detectors observe and record the results of these collisions.

Founded in 1954, the CERN Laboratory sits astride the Franco–Swiss border near Geneva. It was one of Europe’s first joint ventures and now has 20 Member States.

Find out more:

Conference website: http://www.icepp.s.u-tokyo.ac.jp/hcp2012/

LHCb: http://lhcb-public.web.cern.ch/lhcb-public/Welcome.html

CERN Bulletin: A rare sight: http://cdsweb.cern.ch/journal/CERNBulletin/2012/46/News%20Articles/1493237?ln=en

Images, Text, Credit: CERN / LHCb.

Best regards, Orbiter.ch