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martes, 30 de julio de 2013


Hola amigos: A VUELO DE UN QUINDE EL BLOG., una de  las virtudes de un pueblo se demuestra en preparar la comida para invitar al visitante, justamente en Chiclayo, "La Tierra de la Amistad", tierra que prepara una rica y variada gastronomía, que la distinguen los propios y los turistas como la ciudad de comer muy bien, entonces, las familias chiclayanas haciendo un honor a la celebración de las Fiestas Patrias, escogen un plato para compartirlo con toda la familia.
Doña Flor de María Vargas Rodríguez, tuvo la feliz idea de preparar un plato llamado "Causa a la Chiclayana", que fue el último de los platos que nos sirvió hoy 30 de julio de 2013.

Aquí en la imagen observamos a Flor de María Vargas Rodríguez , haciendo un descanso en su casa días antes de su onomástico; 2 de febrero de 2011. Fuente: Archivos del blog/Foto de Oscar Vidal Sánchez Vargas.
Aquí en la imagen observamos un plato de "Causa a la Chiclayana", preparado por Flor de María Vargas Rodríguez el 30 de julio de 2013. Foto: Milagros del Carmen Sánchez Vargas.

- Una porción de peje seco, desaguado
- Una porción de papa batida
- Dos camote  pelados de tamaña mediano
- Tres aceitunas
- Dos plátanos de freír sancochados medianos
- Medio huevo sancochado
- Un trozo de choclo
- Cuatro trozos de yuca sancochada
- Una porción de cebolla frita y sazonada
. Al fondo del plato dos hojas de lechuga

Se sugiere beber chicha de jora, para asentar la exquisita Causa a la Chiclayana.

Guillermo Gonzalo Sánchez Achutegui
Inscríbete en el Foro del blog y participa : A Vuelo De Un Quinde - El Foro!

lunes, 29 de julio de 2013

NASA - NASA's Chandra Sees Eclipsing Planet in X-rays for First Time

A Nearby Stellar Cradle
The Milky Way and other galaxies in the universe harbor many young star clusters and associations that each contain hundreds to thousands of hot, massive, young stars known as O and B stars. The star cluster Cygnus OB2 contains more than 60 O-type stars and about a thousand B-type stars. Deep observations with NASA's Chandra X-ray Observatory have been used to detect the X-ray emission from the hot outer atmospheres, or coronas, of young stars in the cluster and to probe how these fascinating star factories form and evolve. About 1,700 X-ray sources were detected, including about 1,450 thought to be stars in the cluster. In this image, X-rays from Chandra (blue) have been combined with infrared data from NASA's Spitzer Space Telescope (red) and optical data from the Isaac Newton Telescope (orange).
Image Credit: NASA
NASA's Chandra Sees Eclipsing Planet in X-rays for First Time
For the first time since exoplanets, or planets around stars other than the sun, were discovered almost 20 years ago, X-ray observations have detected an exoplanet passing in front of its parent star.
An advantageous alignment of a planet and its parent star in the system HD 189733, which is 63 light-years from Earth, enabled NASA’s Chandra X-ray Observatory and the European Space Agency’s XMM Newton Observatory to observe a dip in X-ray intensity as the planet transited the star.
"Thousands of planet candidates have been seen to transit in only optical light," said Katja Poppenhaeger of Harvard-Smithsonian Center for Astrophysics (CfA) in Cambridge, Mass., who led a new study to be published in the Aug. 10 edition of The Astrophysical Journal. "Finally being able to study one in X-rays is important because it reveals new information about the properties of an exoplanet."
The team used Chandra to observe six transits and data from XMM Newton observations of one.
The planet, known as HD 189733b, is a hot Jupiter, meaning it is similar in size to Jupiter in our solar system but in very close orbit around its star. HD 189733b is more than 30 times closer to its star than Earth is to the sun. It orbits the star once every 2.2 days.
HD 189733b is the closest hot Jupiter to Earth, which makes it a prime target for astronomers who want to learn more about this type of exoplanet and the atmosphere around it. They have used NASA's Kepler space telescope to study it at optical wavelengths, and NASA's Hubble Space Telescope to confirm it is blue in color as a result of the preferential scattering of blue light by silicate particles in its atmosphere.
The study with Chandra and XMM Newton has revealed clues to the size of the planet's atmosphere. The spacecraft saw light decreasing during the transits. The decrease in X-ray light was three times greater than the corresponding decrease in optical light.
"The X-ray data suggest there are extended layers of the planet's atmosphere that are transparent to optical light but opaque to X-rays," said co-author Jurgen Schmitt of Hamburger Sternwarte in Hamburg, Germany. "However, we need more data to confirm this idea."
The researchers also are learning about how the planet and the star can affect one another.
Astronomers have known for about a decade ultraviolet and X-ray radiation from the main star in HD 189733 are evaporating the atmosphere of HD 189733b over time. The authors estimate it is losing 100 million to 600 million kilograms of mass per second. HD 189733b's atmosphere appears to be thinning 25 percent to 65 percent faster than it would be if the planet's atmosphere were smaller.
"The extended atmosphere of this planet makes it a bigger target for high-energy radiation from its star, so more evaporation occurs," said co-author Scott Wolk, also of CfA.
The main star in HD 189733 also has a faint red companion, detected for the first time in X-rays with Chandra. The stars likely formed at the same time, but the main star appears to be 3 billion to 3 1/2 billion years younger than its companion star because it rotates faster, displays higher levels of magnetic activity and is about 30 times brighter in X-rays than its companion.
"This star is not acting its age, and having a big planet as a companion may be the explanation," said Poppenhaeger. "It's possible this hot Jupiter is keeping the star's rotation and magnetic activity high because of tidal forces, making it behave in some ways like a much younger star."
The paper is available online at:
For Chandra images, multimedia and related materials, visit:
For an additional interactive image, podcast, and video on the finding, visit:
Guillermo Gonzalo Sánchez Achutegui

NASA - Exoplanet HD 189733b

Exoplanet HD 189733b
This graphic depicts HD 189733b, the first exoplanet caught passing in front of its parent star in X-rays. As described in our press release , NASA’s Chandra X-ray Observatory and the European Space Agency’s XMM Newton Observatory have been used to observe a dip in X-ray intensity as HD 189733b transits its parent star.
The main figure is an artist’s impression showing the HD 189733 system, containing a Sun-like star orbited by HD 189733b, an exoplanet about the size of Jupiter. This “hot Jupiter” is over 30 times closer to its star than Earth is to the Sun and goes around the star once every 2.2 days, as determined from previous observations. Also in the illustration is a faint red companion star, which was detected for the first time in X-rays with these observations. This star orbits the main star about once every 3,200 years.
The inset contains the Chandra image of HD 189733. The source in the middle is the main star and the source in the lower right is the faint companion star. The source at the bottom of the image is a background object not contained in the HD 189733 system.
The exoplanet itself cannot be seen in the Chandra image, as the transits involve measuring small decreases in X-ray emission from the main star. The authors estimate that the percentage decrease in X-ray light during the transits is about three times greater than the corresponding decrease in optical light. This tells them that the region blocking X-rays from the star is substantially larger than the region blocking optical light from the star, helping to determine the size of the planet's atmosphere. The extended atmosphere implied by these results is shown by the light blue color around the planet. Recent observations of HD 189733b with the Hubble Space Telescope have confirmed that the lower atmosphere of the planet has a deep blue color, due to the preferential scattering of blue light by silicate particles in its atmosphere.
For about a decade astronomers have known that ultraviolet and X-ray radiation from the main star in HD 189733 are evaporating the atmosphere of its closely orbiting planet over time. The authors of the new study estimate that HD 189733b is losing between 100 million and 600 million kilograms per second. This rate is about 25% to 65% higher than it would be if the planet's atmosphere were not extended.
At a distance of just 63 light years, HD 189733b is the closest hot Jupiter to Earth, which makes it a prime target for astronomers who want to learn more about this type of exoplanet and the atmosphere around it.
Chandra was used to make observations of six transits by HD 189733b and the team also used archival data from XMM-Newton for one transit. These results are available online and will appear in the August 10th issue of The Astrophysical Journal.
Credit: X-ray: NASA/CXC/SAO/K. Poppenhaeger et al; Illustration: NASA/CXC/M. Weiss
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Guillermo Gonzalo Sánchez Achutegui

NASA - Black Hole Outburst

Black Hole Outburst
NASA's Chandra X-ray Observatory has discovered an extraordinary outburst by a black hole in the spiral galaxy M83, located about 15 million light years from Earth. Using Chandra, astronomers found a new ultraluminous X-ray source, or ULX. These objects give off more X-rays than most normal binary systems in which a companion star is in orbit around a neutron star or black hole.

Image Credit: NASA/CXC/Curtin University/R.Soria et al.
Guillermo Gonzalo Sánchez Achutegui
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NASA - A Surprisingly Bright Superbubble

A Surprisingly Bright Superbubble
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A Surprisingly Bright Superbubble
This composite image shows a superbubble in the Large Magellanic Cloud (LMC), a small satellite galaxy of the Milky Way located about 160,000 light years from Earth. Many new stars, some of them very massive, are forming in the star cluster NGC 1929, which is embedded in the nebula N44, so named because it is the 44th nebula in a catalog of such objects in the Magellanic Clouds. The massive stars produce intense radiation, expel matter at high speeds, and race through their evolution to explode as supernovas. The winds and supernova shock waves carve out huge cavities called superbubbles in the surrounding gas. X-rays from NASA's Chandra X-ray Observatory (blue) show hot regions created by these winds and shocks, while infrared data from NASA's Spitzer Space Telescope (red) outline where the dust and cooler gas are found. The optical light from the 2.2-m Max-Planck-ESO telescope (yellow) in Chile shows where ultraviolet radiation from hot, young stars is causing gas in the nebula to glow.

A long-running problem in high-energy astrophysics has been that some superbubbles in the LMC, including N44, give off a lot more X-rays than expected from models of their structure. These models assume that hot, X-ray emitting gas has been produced by winds from massive stars and the remains of several supernovas. A Chandra study published in 2011 showed that there are two extra sources of N44's X-ray emission not included in these models: supernova shock waves striking the walls of the cavities, and hot material evaporating from the cavity walls. The Chandra observations also show no evidence for an enhancement of elements heavier than hydrogen and helium in the cavities, thus ruling out this possibility as a third explanation for the bright X-ray emission. Only with long observations making full use of the capabilities of Chandra has it now become possible to distinguish between different sources of the X-rays produced by superbubbles.

Image credit: X-ray: NASA/CXC/U.Mich./S.Oey, IR: NASA/JPL, Optical: ESO/WFI/2.2-m

Caption credit: Harvard-Smithsonian Center for Astrophysics
Guillermo Gonzalo Sánchez Achutegui
Inscríbete en el Foro del blog y participa : A Vuelo De Un Quinde - El Foro!

NASA - X-rays From A Young Supernova Remnant

X-rays From A Young Supernova Remnant
More than fifty years ago, a supernova was discovered in M83, a spiral galaxy about 15 million light years from Earth. Astronomers have used NASA's Chandra X-ray Observatory to make the first detection of X-rays emitted by the debris from this explosion.

Named SN 1957D because it was the fourth supernova to be discovered in the year 1957, it is one of only a few located outside of the Milky Way galaxy that is detectable, in both radio and optical wavelengths, decades after its explosion was observed. In 1981, astronomers saw the remnant of the exploded star in radio waves, and then in 1987 they detected the remnant at optical wavelengths, years after the light from the explosion itself became undetectable.

A relatively short observation - about 14 hours long - from NASA's Chandra X-ray Observatory in 2000 and 2001 did not detect any X-rays from the remnant of SN 1957D. However, a much longer observation obtained in 2010 and 2011, totaling nearly 8 and 1/2 days of Chandra time, did reveal the presence of X-ray emission. The X-ray brightness in 2000 and 2001 was about the same as or lower than in this deep image.

This new Chandra image of M83 is one of the deepest X-ray observations ever made of a spiral galaxy beyond our own. This full-field view of the spiral galaxy shows the low, medium, and high-energy X-rays observed by Chandra in red, green, and blue respectively.

The new X-ray data from the remnant of SN 1957D provide important information about the nature of this explosion that astronomers think happened when a massive star ran out of fuel and collapsed. The distribution of X-rays with energy suggests that SN 1957D contains a neutron star, a rapidly spinning, dense star formed when the core of pre-supernova star collapsed. This neutron star, or pulsar, may be producing a cocoon of charged particles moving at close to the speed of light known as a pulsar wind nebula.

If this interpretation is confirmed, the pulsar in SN 1957D is observed at an age of 55 years, one of the youngest pulsars ever seen. The remnant of SN 1979C in the galaxy M100 contains another candidate for the youngest pulsar, but astronomers are still unsure whether there is a black hole or a pulsar at the center of SN 1979C.

Image Credits: X-ray: NASA/CXC/STScI/K.Long et al., Optical: NASA/STScI
Guillermo Gonzalo Sánchez Achutegui

NASA - Cloud Streets over the Bering Sea

The Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Terra satellite captured this natural-color image of clouds stretched in parallel rows over the Bering Sea on April 7, 2013. Image Credit: NASA GSFC
Cloud Streets over the Bering Sea
In early April 2013, clouds stretched in parallel rows for hundreds of kilometers over the Bering Sea. The Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Terra satellite captured this natural-color image of the phenomenon on April 7, 2013.
The parallel clouds, known as cloud streets, originated along the edge of the sea ice, which extended southward from the snow-covered expanses of Russia and Alaska. The location of the cloud formation was not a coincidence. When cold air blows over ice and snow and encounters moist air over open water, the meeting of the air masses can cause the formation of parallel cylinders of spinning air. Clouds form along the upward cycle in the cylinders, where air is rising, and skies remain clear along the downward cycle, where air is falling.
In the north, light cloud cover partially obscured the sea ice, but its characteristic tendril shapes could still be seen through the clouds.
Image Credit: Jeff Schmaltz, LANCE/EOSDIS MODIS Rapid Response Team at NASA GSFC
Caption: Michon Scott
Guillermo Gonzalo Sánchez Achutegui
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nsf.gov - News - NSF Awards Third Round of Grants to Advance Digitization of Biodiversity Collections

Funding will shed light on "dark data," and integrate organismal, vocal, fossil, and ecological information.-

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Aresearcher using the Rapid Image Processing with Voice Recognition
Rapid Image Processing with Voice Recognition aids steps in specimen processing.
Credit: Susan Butts, Yale Peabody Museum
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Fossilized damselfly from the 34-million-year-old Florissant Formation of Colorado.
Fossilized damselfly from the 34-million-year-old Florissant Formation of Colorado.
Credit: University of Colorado Museum of Natural History
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Scientists Roy Tsuda and Varnelle Magoon study a red algae specimen in Hawaii.
Scientists Roy Tsuda and Varnelle Magoon study a red algae specimen in Hawaii.
Credit: Shelley James, Bishop Museum
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Curator Kathy Ann Miller looks at seaweed collected along the coast of Washington.
Curator Kathy Ann Miller looks at seaweed collected along the coast of Washington.
Credit: Sheraz Sadiq, KQED Science
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Fly specimen
NSF's ADBC Program will foster advances in digitizing biological specimen collections.
Credit: Santiago Ramirez, Museum of Comparative Zoology, Harvard University
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Researcher Clare Loughran takes a digital photo of a red seaweed using a special light box.
Researcher Clare Loughran takes a digital photo of a red seaweed using a special light box.
Credit: Sheraz Sadiq, KQED Science
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Over centuries of discovery, the diversity of life on Earth has been documented in numerous ways.
Records of that biodiversity are, however, often obscured in varied and distinct natural history collections, making accessing the information a difficult task.
The National Science Foundation (NSF), through its Advancing Digitization of Biodiversity Collections (ADBC) Program, is responding to the need for greater accessibility of biodiversity collections data by awarding major new grants.
The funding will expand the scope of the national resource of digital data documenting existing biodiversity collections.
The awards are part of the National Resource for Digitization of Biological Collections; all data resulting from the awards will be available through the national resource.
Biological diversity is critical to the future of planet Earth, say researchers. Incomplete information on species, their distributions and environmental and biological changes over time make it difficult, however, to assess the status of and changes in biodiversity.
Much of the relevant information exists in research collections, scientists say, but the majority isn't integrated and isn't readily available online.
It's "dark data"--inaccessible to most biologists, policy-makers and the general public.
"The ADBC program continues to grow in the breadth of its collections, including fossils, and in the depth of additional information about each specimen," says John Wingfield, NSF assistant director for Biological Sciences.
"The collections being digitized are unprecedented in their worth to research and education and hold huge potential for future development and integration with other biological data from genomes to phenomes," says Wingfield.
"With the diversity of information digitized, these projects are addressing issues of interoperability, access and analysis--'big data.' The benefits will be felt for many generations to come."
The program will result in more efficient and innovative ways of providing access to information in biological and paleontological research collections.
It will also help speed up the process of integrating diverse information on the genetic, ecological, organismal (including vocalizations), molecular biology and evolutionary history of specimens in collections.
"During the past 200 or more years, an abundance of fossil collections that are scientifically documented, biotically diverse and geologically distributed in time and space has been accessioned into non-federal museums across the U.S.," says Wendy Harrison, director of NSF's Division of Earth Sciences.
Such collections, she says, are the building blocks for paleontology, stratigraphy, paleogeography, paleoceanography and paleoecology.
"These scientific 'treasures' are of great importance to our search and production of fossil fuels and minerals, as well as to unraveling the history of the Earth and life itself," says Harrison.
"Having the vital statistics and visuals of these collections available on the Web will place these sciences on a new level of integration and understanding."
Standardized digital photos of specimens will be linked with, for example, sound recordings, pathogens found on the specimens, stratigraphic information for fossils, environmental variables at the collecting localities and electron micrographs.
"Insects, for example, have a long geologic history, providing a deep-time record of ecological and evolutionary responses to environmental changes," says H. Richard Lane, program director in NSF's Division of Earth Sciences.
"With current models of future climate change and the important role insects play in human society, the ability to access modern and fossil archived data to make predictions about future insect populations becomes urgent."
Training for future researchers on collections techniques, informatics technology and data integration is part of ADBC efforts.
The awards provide graduate and undergraduate training opportunities and outreach to K-12 educators, students and non-scientists.
Each of the three Thematic Collections Networks (TCN) focuses on "grand challenge," or major scientific, questions in biodiversity, and offers multiple research opportunities as data become widely available.
"The new fossil insect TCN, for example, promises to accelerate our understanding of the insect world--past, present and future," says Lane.
The awards include 65 institutions in 29 states and one territory.
In addition, five Partners to Existing Networks (PEN) were funded.
These efforts allow institutions that were not fully ready to participate in a TCN to add to their collections and fill in gaps.
Two PEN awards have been made that will increase the coverage of the Paleoniches TCN. The TCN is focused on critical specimens needed to identify organisms and environments from ages and localities not previously included.
A third PEN will expand the Southwest Arthropod Network, which also includes field guides for the Navajo reservation area; a fourth PEN will add central Midwest specimens to the InvertNet TCN; and a fifth will add two historically important collections to the lichen and bryophyte TCN.
2013 NSF ADBC Awards
Title: (TCN) Fossil Insect Collaborative: A Deep-Time Approach to Studying Diversification and Response to Environmental Change
PI (Principal Investigator):
Collaboratoring Award PIs: Sam Heads, University of Illinois Urbana-Champaign; David Grimaldi, American Museum of Natural History; Alton Dooley, Virginia Museum of Natural History; Michael Engle, University of Kansas; Brian Farrell, Harvard University; Susan Butts, Yale University.
Title: (TCN) Developing a Centralized Digital Archive of Vouchered Animal Communication Signals
PI (Principal Investigator):
Collaboratoring Award PIs: Rafe Brown, University of Kansas; David Kavanaugh, California Academy of Sciences; Travis LaDuc, University of Texas at Austin; Daniel Lane, Louisiana State University & Agricultural and Mechanical College.
Title: (TCN) The Macroalgal Herbarium Consortium: Accessing 150 Years of Specimen Data to Understand Changes in the Marine/Aquatic Environment
PI (Principal Investigator):
Collaboratoring Award PIs: Christopher Dick, University of Michigan, Ann Arbor; Brent Mishler, University of California Berkeley; David Giblin, University of Washington; Alan Weakley, University of North Carolina at Chapel Hill; Kenneth Karol, New York Botanical Garden.
The five PEN awards are:
Title: (PEN) Targeted Digitization to Expand and Enhance the PALEONICHES TCN
Title: (PEN) Increasing the Robustness of the Ordovician and Pennsylvanian Dataset of PALEONICHES-TCN
Title: (PEN) Facilitating a Shared Image Library and Occurrence Database for Ants of the Southwest as Part of the SCAN TCN
Title: (PEN) Digitizing the University of Iowa Museum of Natural History's Historic Invertebrate Collections through the InvertNet TCN
Title: (PEN) Digitization of two Important Medium-sized Collections to Join the North American Bryophytes and Lichens TCN

Media Contacts Cheryl Dybas, NSF (703) 292-7734

Related WebsitesNSF News: NSF Awards Second Round of Grants to Advance Digitization of Biological Collections: http://www.nsf.gov/news/news_summ.jsp?cntn_id=124031
NSF News: NSF Awards First Round of Grants to Advance Digitization of Biological Collections: http://www.nsf.gov/news/news_summ.jsp?cntn_id=121015&org=NSF&from=news

The National Science Foundation (NSF) is an independent federal agency that supports fundamental research and education across all fields of science and engineering. In fiscal year (FY) 2012, its budget was $7.0 billion. NSF funds reach all 50 states through grants to nearly 2,000 colleges, universities and other institutions. Each year, NSF receives about 50,000 competitive requests for funding, and makes about 11,500 new funding awards. NSF also awards about $593 million in professional and service contracts yearly.
Useful NSF Web Sites:
NSF Home Page:
NSF News:
For the News Media:
Science and Engineering Statistics:

The National Science Foundation (NSF).
Guillermo Gonzalo Sánchez Achutegui
Inscríbete en el Foro del blog y participa : A Vuelo De Un Quinde - El Foro!

NASA - Hubble Eyes a Mysterious Old Spiral

Hubble Eyes a Mysterious Old Spiral
This striking cosmic whirl is the center of galaxy NGC 524, as seen with the NASA/ESA Hubble Space Telescope. This galaxy is located in the constellation of Pisces, some 90 million light-years from Earth.
NGC 524 is a lenticular galaxy. Lenticular galaxies are believed to be an intermediate state in galactic evolution — they are neither elliptical nor spiral. Spirals are middle-aged galaxies with vast, pin wheeling arms that contain millions of stars. Along with these stars are large clouds of gas and dust that, when dense enough, are the nurseries where new stars are born. When all the gas is either depleted or lost into space, the arms gradually fade away and the spiral shape begins to weaken. At the end of this process, what remains is a lenticular galaxy — a bright disc full of old, red stars surrounded by what little gas and dust the galaxy has managed to cling on to.
This image shows the shape of NGC 524 in detail, formed by the remaining gas surrounding the galaxy’s central bulge. Observations of this galaxy have revealed that it maintains some spiral-like motion, explaining its intricate structure.
Credit: ESA/Hubble & NASA, Acknowledgement: Judy Schmidt
Guillermo Gonzalo Sánchez Achutegui

NASA - NASA's WISE Finds Mysterious Centaurs May Be Comets

Artist's concept shows a Centaur creature together with asteroids
This artist's concept shows a centaur creature together with asteroids on the left and comets at right.
Image Credit:  NASA/JPL-Caltech
PASADENA, Calf. -- The true identity of centaurs, the small celestial bodies orbiting the sun between Jupiter and Neptune, is one of the enduring mysteries of astrophysics. Are they asteroids or comets? A new study of observations from NASA's Wide-field Infrared Survey Explorer (WISE) finds most centaurs are comets.
Until now, astronomers were not certain whether centaurs are asteroids flung out from the inner solar system or comets traveling in toward the sun from afar. Because of their dual nature, they take their name from the creature in Greek mythology whose head and torso are human and legs are those of a horse.
"Just like the mythical creatures, the centaur objects seem to have a double life," said James Bauer of NASA's Jet Propulsion Laboratory in Pasadena, Calif. Bauer is lead author of a paper published online July 22 in the Astrophysical Journal. "Our data point to a cometary origin for most of the objects, suggesting they are coming from deeper out in the solar system."
"Cometary origin" means an object likely is made from the same material as a comet, may have been an active comet in the past, and may be active again in the future.
The findings come from the largest infrared survey to date of centaurs and their more distant cousins, called scattered disk objects. NEOWISE, the asteroid-hunting portion of the WISE mission, gathered infrared images of 52 centaurs and scattered disk objects. Fifteen of the 52 are new discoveries. Centaurs and scattered disk objects orbit in an unstable belt. Ultimately, gravity from the giant planets will fling them either closer to the sun or farther away from their current locations.
Although astronomers previously observed some centaurs with dusty halos, a common feature of outgassing comets, and NASA's Spitzer Space Telescope also found some evidence for comets in the group, they had not been able to estimate the numbers of comets and asteroids.
Infrared data from NEOWISE provided information on the objects' albedos, or reflectivity, to help astronomers sort the population. NEOWISE can tell whether a centaur has a matte and dark surface or a shiny one that reflects more light. The puzzle pieces fell into place when astronomers combined the albedo information with what was already known about the colors of the objects. Visible-light observations have shown centaurs generally to be either blue-gray or reddish in hue. A blue-gray object could be an asteroid or comet. NEOWISE showed that most of the blue-gray objects are dark, a telltale sign of comets. A reddish object is more likely to be an asteroid.
"Comets have a dark, soot-like coating on their icy surfaces, making them darker than most asteroids," said the study's co-author, Tommy Grav of the Planetary Science Institute in Tucson, Ariz. "Comet surfaces tend to be more like charcoal, while asteroids are usually shinier like the moon."
The results indicate that roughly two-thirds of the centaur population are comets, which come from the frigid outer reaches of our solar system. It is not clear whether the rest are asteroids. The centaur bodies have not lost their mystique entirely, but future research from NEOWISE may reveal their secrets further.
The paper is available online at:
JPL, managed by the California Institute of Technology in Pasadena, managed and operated WISE for NASA's Science Mission Directorate. The NEOWISE portion of the project was funded by NASA's Near Earth Object Observation Program. WISE completed its key mission objective, two scans of the entire sky, in 2011 and has been hibernating in space since then.
For more information about the WISE mission, visit:
Whitney Clavin 818-354-4673
Jet Propulsion Laboratory, Pasadena, Calif.
J.D. Harrington 202-358-5241
Headquarters, Washington
Guillermo Gonzalo Sánchez Achutegui
Inscríbete en el Foro del blog y participa : A Vuelo De Un Quinde - El Foro!

nsf.gov - National Science Foundation - Sick Sea Fans: Undersea "Doctors" to the Rescue

Scientists discover genes involved in immunity of sea fans to coral diseases.-

collage of various pictures showing researchers, seafans and corals
In sea fans, scientists discover new immunity genes. See photo gallery for sea fan 'Message in a Bottle.'
Credit: NSF

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A sea fan  with dark purple inflammation.
A sea fan fights back against disease; its response is marked by dark purple inflammation.
Credit: E. Weil
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Scientist Drew Harvell examines sea fansunder water
Scientist Drew Harvell examines sea fans in Puerto Rico for signs of recovery.
Credit: E. Weil
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A purple sea fan under water
Beautiful and healthy now, the purple sea fan may fall ill from a host of infectious diseases.
Credit: Wikimedia Commons
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Close-up of a sea fan recovering nicely from ocean diseases.
Close-up of formerly sick sea fan that's recovering nicely from ocean diseases.
Credit: D. Harvell
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Marine ecologist Ernesto Weil diving to look at a sick sea fan
Marine ecologist Ernesto Weil looks at a sick sea fan; he's studying sea fan immune systems.
Credit: D. Harvell
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The following is part five in a series on the NSF-NIH Ecology and Evolution of Infectious Diseases (EEID) Program. For part one, see Cool Cat in a Hot Zone. For part two:
Like all of us, corals get sick. They respond to pathogens (disease-causing microbes) and recover or die. But unlike us, they can't call a doctor for treatment.
Instead, help has arrived in the form of scientists who study the causes of the corals' disease, and the immune factors that might be important in their response and resistance.
With support from the National Science Foundation (NSF), scientists Drew Harvell and Colleen Burge of Cornell University and their colleagues have developed a catalog of genes that, the researchers say, will allow us to better understand the immune systems of corals called sea fans.
The marine ecologists have trained their undersea eyes on a particular sea fan species, Gorgonia ventalina, or the purple sea fan, found in the western Atlantic Ocean and the Caribbean Sea.
The team has monitored sea fan health in the Florida Keys, Mexican Yucatan and Puerto Rico for the past 15 years. The most recent research, in collaboration with Ernesto Weil of the University of Puerto Rico, is underway on reefs at La Parguera, Puerto Rico.
Gorgonia ventalina is a fan-shaped coral with several main branches and a latticework of smaller branches. Its skeleton is composed of calcite and gorgonian, a collagen-like compound. Purple sea fans often have smaller, accessory fans growing sideways out of their main fans.
These large sea fans fare best near shore in shallow waters with strong waves and on deeper outer reefs with strong currents, down to a depth of about 50 feet. Small polyps on the graceful fans catch plankton drifting by on fast-flowing currents.
Turning (more) purple
Life as a purple sea fan isn't always easy. The coral may be attacked by the fungus Aspergillus sydowii, which causes the disease aspergillosis.
It results in damaged patches on the fan, extreme purpling of tissues and sometimes death. Several outbreaks of aspergillosis have occurred in the Caribbean; corals in stressful conditions such as warming waters may be especially susceptible.
"Diseases and climate change are very tightly linked," says Mike Lesser, program director in NSF's Division of Ocean Sciences, which funds the research along with the joint NSF-National Institutes of Health Evolution and Ecology of Infectious Diseases (EEID) Program.
"The role of climate change in diseases is important," Lesser says, "for understanding the spread of infectious diseases in every corner of the globe, including the oceans."
Adds Sam Scheiner, NSF EEID program director, "Human-induced climate change is having profound effects on many parts of the world. As this research shows, coral reefs are being decimated by the combination of climate change and infectious diseases."
Undersea "doctors" come to sea fans' aid
Harvell agrees.
In a paper published earlier this year in The Annual Review of Marine Science, Harvell, Burge and other scientists reviewed climate change influences on marine infectious diseases.
Now the scientists are using the purple sea fan as a model for studying ocean diseases. "We're looking at microbial infection, pathways of defense and the health of this sea fan in the face of warming waters and climate change," says Harvell.
"All animals on Earth--from humans to fish to corals--are susceptible to infection by pathogens that cause illness," she says. "What we hope to answer is: How widespread are these infections? Why do they happen? And, what can we do about them?"
Coral reefs are declining worldwide. Even very old coral colonies in remote locations are dying. "Disease-related deaths are caused in part by pathogens alone and in part by interactions between pathogens and climate change," says Burge.
Many of these pathogens are unidentified, leaving sea fans and their coral relatives at high risk.
But the mystery is slowly being solved.
The scientists have discovered two pathogens in purple sea fans. The microbes are being cultured and used to examine how sea fans' immune systems work.
Past is prologue?
A look back a decade or more may provide clues to the present--and the future--for sea fans.
From 1996 through 2004, thousands of sea fans in the Caribbean died of aspergillosis. Many survived, however, and appear resistant to further attack.
But they're far from home free.
Purple sea fans are now being infected by a new pathogen, called Aplanochytrium. Burge was the first to isolate and culture the microbe from a sick sea fan.
Aplanochytrium is a member of an order of lethal microbes known as Labyrinthulomycetes. It grows faster at warmer temperatures, leaving sea fans in "hot water."
Corals don't have "immune memory," such as the T cells and antibodies found in humans. Instead they have an ancient defense system called the innate immune system.
Studying sea fans' immunity through their genes is an important step in protecting them, says Burge.
"We used molecular biology and bioinformatics--a combination of biology, computer science and information technology--to make a set of the genes' messages, called transcripts," she says. "Then we characterized these messages, which are known collectively as a transcriptome."
The results, reported this month in a paper in the journal Frontiers in Physiology, are the first to show which genes are activated in response to pathogens in sea fans. Co-authors of the paper are Burge, Harvell and Morgan Mouchka of Cornell, and Steven Roberts of the University of Washington.
Message in a (genetic) bottle
The purple sea fan may hold messages for the oceans, and for us, but the messages come in a genetic bottle.
The scientists studied what's called messenger RNA, which transfers genetic messages, in sea fans exposed to Aplanochytrium, comparing it with that of unexposed sea fans.
They found that the sea fans' genes hold clues to questions such as how the fans recognize and kill pathogens, and how they repair injured tissues.
The scientists are increasing the sea fan genetic "catalog" by adding genes expressed, or turned on, in response to record-breaking Caribbean Sea temperatures in 2010.
The researchers, working in Puerto Rico with Weil and Laura Mydlarz of the University of Texas at Arlington, assessed the effect of the 2010 Caribbean coral bleaching event, as it's known, on sea fans' genes and immune function.
The study compared immune system genes in a heat-sensitive coral species, Orbicella annularis, the boulder star coral, with that of Gorgonia ventalina.
The purple sea fan was thought to be resilient to the stresses of warming waters. But Gorgonia ventalina, the scientists found, is also susceptible to the double whammy of disease and warming.
-- Cheryl Dybas, NSF (703) 292-7734 cdybas@nsf.gov
Related WebsitesNSF Special Report: The Ecology and Evolution of Infectious Diseases:
NSF Award: EEID: Evaluating the Effects of a Changing Ocean on Management and Ecology of Infectious Marine Disease:
NSF Award: Effect of the 2010 Caribbean Coral Bleaching Event:
NSF News: Controlling the Spread of Diseases Among Humans, Other Animals and the Environment:
Guillermo Gonzalo Sánchez Achutegui

NASA - NASA's Van Allen Probes Discover Particle Accelerator in the Heart of Earth’s Radiation Belts

Particle acceleration comes from the Van Allen radiation belts.
Recent observations by NASA’s twin Van Allen Probes show that particles in the radiation belts surrounding Earth are accelerated by a local kick of energy, helping to explain how these particles reach speeds of 99 percent the speed of light.
Image Credit:  G. Reeves/M. Henderson
Scientists have discovered a massive particle accelerator in the heart of one of the harshest regions of near-Earth space, a region of super-energetic, charged particles surrounding the globe called the Van Allen radiation belts. Scientists knew that something in space accelerated particles in the radiation belts to more than 99 percent the speed of light but they didn't know what that something was. New results from NASA's Van Allen Probes now show that the acceleration energy comes from within the belts themselves. Particles inside the belts are sped up by local kicks of energy, buffeting the particles to ever faster speeds, much like a perfectly timed push on a moving swing.
The discovery that the particles are accelerated by a local energy source is akin to the discovery that hurricanes grow from a local energy source, such as a region of warm ocean water. In the case of the radiation belts, the source is a region of intense electromagnetic waves, tapping energy from other particles located in the same region. Knowing the location of the acceleration will help scientists improve space weather predictions, because changes in the radiation belts can be risky for satellites near Earth. The results were published in Science magazine on July 25, 2013.
In order for scientists to understand the belts better, the Van Allen Probes were designed to fly straight through this intense area of space. When the mission launched in August 2012, it had top-level goals to understand how particles in the belts are accelerated to ultra-high energies, and how the particles can sometimes escape. By determining that this superfast acceleration comes from these local kicks of energy, as opposed to a more global process, scientists have been able to definitively answer one of those important questions for the first time.
"This is one of the most highly anticipated and exciting results from the Van Allen Probes," said David Sibeck, Van Allen Probes project scientist at NASA's Goddard Space Flight Center in Greenbelt, Md. "It goes to the heart of why we launched the mission."
The radiation belts were discovered upon the launch of the very first successful U.S. satellites sent into space, Explorers I and III. It was quickly realized that the belts were some of the most hazardous environments a spacecraft can experience. Most satellite orbits are chosen to duck below the radiation belts or circle outside of them, and some satellites, such as GPS spacecraft, must operate between the two belts. When the belts swell due to incoming space weather, they can encompass these spacecraft, exposing them to dangerous radiation. Indeed, a significant number of permanent failures on spacecraft have been caused by radiation. With enough warning, we can protect technology from the worst consequences, but such warning can only be achieved if we truly understand the dynamics of what's happening inside these mysterious belts.
"Until the 1990s, we thought that the Van Allen belts were pretty well-behaved and changed slowly," said Geoff Reeves, the first author on the paper and a radiation belt scientist at Los Alamos National Laboratory in Los Alamos, N.M. "With more and more measurements, however, we realized how quickly and unpredictably the radiation belts changed. They are basically never in equilibrium, but in a constant state of change."
In fact, scientists realized that the belts don't even change consistently in response to what seem to be similar stimuli. Some solar storms caused the belts to intensify; others caused the belts to be depleted, and some seemed to have almost no effect at all. Such disparate effects from apparently similar events suggested that this region is much more mysterious than previously thought. To understand – and eventually predict – which solar storms will intensify the radiation belts, scientists want to know where the energy that accelerates the particles comes from.
The twin Van Allen Probes were designed to distinguish between two broad possibilities on what processes accelerate the particles to such amazing speeds: radial acceleration or local acceleration. In radial acceleration, particles are transported perpendicular to the magnetic fields that surround Earth, from areas of low magnetic strength far from Earth to areas of high magnetic strength nearer Earth. The laws of physics dictate that the particle speeds in this scenario will speed up when the magnetic field strength increases. So the speed would increase as the particles move toward Earth, much the way a rock rolling down hill gathers speed simply due to gravity. The local acceleration theory posits that the particles gain energy from a local energy source more similar to the way hot ocean water spawns a hurricane above it.
Graphic of Earth's radiation belts and the orbit of the Van Allen Probes.
Two swaths of particles surrounding Earth called the radiation belts are one of the greatest natural accelerators in the solar system, able to push particles up to 99% the speed of light. The Van Allen Probes launched in August 2012, have now discovered mechanisms behind this acceleration.
Image Credit:  NASA/Goddard /Scientific Visualization Studio
To help distinguish between these possibilities, the Van Allen Probes consist of two spacecraft. With two sets of observations, scientists can measure the particles and energy sources in two regions of space simultaneously, which is crucial to distinguish between causes that occur locally or come from far away. Also, each spacecraft is equipped with sensors to measure particle energy and position and determine pitch angle – that is, the angle of movement with respect to Earth's magnetic fields. All of these will change in different ways depending on the forces acting on them, thus helping scientists distinguish between the theories.
Equipped with such data, Reeves and his team observed a rapid energy increase of high-energy electrons in the radiation belts on Oct. 9, 2012. If the acceleration of these electrons was occurring due to radial transport, one would measure effects starting first far from Earth and moving inward due to the very shape and strength of the surrounding fields. In such a scenario, particles moving across magnetic fields naturally jump from one to the next in a similar cascade, gathering speed and energy along the way – correlating to that scenario of rocks rolling down a hill.
But the observations didn't show an intensification that formed further away from Earth and gradually moved inward. Instead they showed an increase in energy that started right in the middle of the radiation belts and gradually spread both inward and outward, implying a local acceleration source.
"In this particular case, all of the acceleration took place in about 12 hours," said Reeves. "With previous measurements, a satellite might have only been able to fly through such an event once, and not get a chance to witness the changes actually happening. With the Van Allen Probes we have two satellites and so can observe how things change and where those changes start."
Scientists believe these new results will lead to better predictions of the complex chain of events that intensify the radiation belts to levels that can disable satellites. While the work shows that the local energy comes from electromagnetic waves coursing through the belts, it is not known exactly which such waves might be the cause. During the set of observations described in the paper, the Van Allen Probes observed a specific kind of wave called chorus waves at the same time as the particles were accelerated, but more work must be done to determine cause and effect.
"This paper helps differentiate between two broad solutions," said Sibeck. "This shows that the acceleration can happen locally. Now the scientists who study waves and magnetic fields will jump in to do their job, and find out what wave provided the push."
Luckily, such a task will also be helped along by the Van Allen Probes, which were also carefully designed to measure and distinguish between the numerous types of electromagnetic waves.
“When scientists designed the mission and the instrumentation on the probes, they looked at the scientific unknowns and said, ‘This is a great chance to unlock some fundamental knowledge about how particles are accelerated,’” said Nicola J. Fox, deputy project scientist at the Johns Hopkins University Applied Physics Laboratory in Laurel, Md. “With five identical suites of instruments on board twin spacecraft – each with a broad range of particle and field and wave detection – we have the best platform ever created to better understand this critical region of space above Earth.”
The Applied Physics Laboratory built and operates the twin Van Allen Probes for NASA’s Science Mission Directorate. The Van Allen Probes comprise the second mission in NASA's Living With a Star program, managed by Goddard, to explore aspects of the connected sun-Earth system that directly affect life and society.
For more information about the Van Allen probes, visit:
Karen C. Fox
NASA's Goddard Space Flight Center, Greenbelt, Md.
Guillermo Gonzalo Sánchez Achutegui