-Scientific studies done with the “PAPER” array, one of the world-class scientific instruments in South Africa’s Karoo Radio Astronomy Reserve, is producing ground-breaking science and spectacular cosmic images, resulting in several important articles in top astronomy journals.
-The first scientific paper based on observations performed with South Africa’s new KAT-7 radio telescope, has been accepted for publication by the prestigious journal Monthly Notices of the Royal Astronomy Society.
“This is a significant milestone for South Africa’s SKA project, proving that our engineers are able to deliver a cutting-edge scientific instrument, and that our scientists are able to use it for frontier science,” says Derek Hanekom, South Africa’s Minister of Science and Technology. “It bodes well for the delivery of our 64-dish MeerKAT telescope, currently under construction in the Karoo, and for our ability to play a key role in building and commissioning thousands of SKA antennas over the next ten years.”... Read more »
SKA SA Project Office. (2013) Ground-breaking science and spectacular cosmic images from the PAPER instrument in the Karoo. SKA Africa . info:/
1.TAU team takes part in discovering new planet
A team of astronomers at TAU and the Harvard-Smithsonian Center for Astrophysics have announced the first-ever discovery of an extrasolar planet via induced relativistic beaming of light from the host star.
2.New Method of Finding Planets Scores its First Discovery
- CfA... Read more »
TAU News office. (2013) TAU team takes part in discovering new planet. Tel Aviv University. info:/
Scientists have found, for the first time, an alien planet, dubbed as "Einstein's planet", with the help of the Einstein's Theory of Relativity.
The Astrophysical Journal
"Einstein's planet" is officially called as Kepler-76b and is the first planet found by this method. It is the latest of the 800 planets located beyond our Solar System.
This planet is 25% larger than Jupiter and is two times of its weight; thereby scientists put it in the class known as "hot Jupiters". It revolves around its star in 1.5 days. This planet has a temperature of about 3,600 degrees Fahrenheit. This star is located about 2,000 light years away from us in the constellation Cygnus.
Researchers used the “beaming” effect predicted by Albert Einstein's Special Theory of Relativity. This special effect can be found when the star brightens up or down as the planet causes it to move towards or away from Earth.
"This is the first time that this aspect of Einstein's theory of relativity has been used to discover a planet," research team member Tsevi Mazeh of Tel Aviv University in Israel said in a statement.
Moreover, the revolving planet cause the star to stretch slightly into a football shape causing it to brighten up on its wider face showing more surface area. Additionally, the planet also reflected the small amount of starlight.
"We are looking for very subtle effects," said team member David Latham of the Harvard-Smithsonian Center for Astrophysics in Cambridge, Mass. "We needed high quality measurements of stellar brightnesses, accurate to a few parts per million."
According to the scientists, this new Einstein-based method has advantage of not requiring high-precision measurements of the star’s velocity and is best for huge planets but not for Earth-sized planets.
Center for Astrophysics via Space via Fox News
Simchon Faigler, Lev Tal-Or, Tsevi Mazeh, Dave W. Latham, & Lars A. Buchhave (2013). BEER analysis of Kepler and CoRoT light curves: I. Discovery of
Kepler-76b: A hot Jupiter with evidence for superrotation The Astrophysical Journal arXiv: 1304.6841v3... Read more »
Simchon Faigler, Lev Tal-Or, Tsevi Mazeh, Dave W. Latham, & Lars A. Buchhave. (2013) BEER analysis of Kepler and CoRoT light curves: I. Discovery of Kepler-76b: A hot Jupiter with evidence for superrotation. The Astrophysical Journal. arXiv: 1304.6841v3
A new kind of cosmic flash may reveal something never seen before: the birth of a black hole.... Read more »
Marcus Woo. (2013) Birth of a Black Hole. Caltech news . info:/
ESA’s Herschel space observatory has made detailed observations of surprisingly hot molecular gas that may be orbiting or falling towards the supermassive black hole lurking at the centre of our Milky Way galaxy.... Read more »
ESA. (2013) Herschel finds hot gas on the menu for milky way's black hole. ESA Herschel. info:/
The Moon clung to its magnetic field until at least 3.56 billion years ago, a study suggests — about 160 million years longer than scientists had thought.
That small change may be enough to rule out some ideas about how the Moon generated and held onto its ancient magnetism, through a process known as a dynamo.
“It seems like the lunar dynamo lasted very late in the Moon’s history,” says Benjamin Weiss, a palaeomagnetics expert at the Massachusetts Institute of Technology (MIT) in Cambridge. “That’s a very surprising result.”... Read more »
A little over a year ago, a research team started to develop a vital part of a Finnish invention – an electric solar wind sail for interplanetary journeys. Now, a prototype has been successfully manufactured and tested.... Read more »
Anneli Waara. (2013) One step closer to solar wind-powered spacecraft. Uppsala University. info:/
IntroductionThe European Space Agency’s Venus Express (VEX) is the only active spacecraft mission at the planet Venus. It carries a number of instruments: A magnetometer, a wide-angle CCD camera, a space plasma detector, a Fourier spectrometer, a thermal spectrometer, a radio science package, and a cluster of spectrometers specifically designed to study the Venusian atmosphere: SPICAV (Spectroscopy for Investigation of Characteristics of the Atmosphere of Venus). This package contains three spectrometers, one of which operates in the ultraviolet and is the subject of this article.The InstrumentThe UV instrument in SPICAV (described in great detail in Bertaux et al. 2007) is a refurbished flight spare from the Mars Express spacecraft. Sensitive to wavelengths from 118 to 320 nm, it was designed to measure different aspects of the atmosphere in different modes. In nadir orientation, SPICAV-UV measures SO2 and the distribution of the mysterious UV absorber in the clouds. On the night side, it observes the γ and δ bands of NO, and it can measure vertical profiles of CO2, SO2, clouds, and aerosols in stellar occultation mode.The UV spectrometer collects light with a 40 mm off-axis parabolic mirror that reflects light toward the spectrometer entrance. There is a configurable slit mechanism in the focal plane that, when left in place, is used for extended source viewing. The slit can be removed from the focal plane entirely for stellar occultation observations. A concave UV grating causes the spectrum to fall onto an image intensifier that is blind to wavelengths greater than 320 nm. The image created on the phosphor output screen of the intensifier is transferred to a 288x384 pixel CCD which can optionally be cooled to 270K using a Peltier cooling unit to reduce dark current. The focal length of the telescope (120mm) results in each CCD pixel having a FOV of 0.01 x 0.01°.The slit of the spectrometer is divided into two parts with different widths to allow differing spectral resolutions during observing of an extended source. The narrow part of the slit is 50 μm wide, giving resolving power between 120 and 300 with lower flux, while the wider part (500 μm) provides more sensitivity at the expense of a lower resolving power of ≈20.Public DatasetsSPICAV-UV data (in fact, all ESA data more than six months old) are available to the public as part of the ESA Planetary Science Archive (PSA), and are found at http://www.rssd.esa.int/index.php?project=PSA&page=vex. NASA’s Planetary Data System (PDS) standard was adopted by the PSA as a baseline for defining the structure and format of datasets. The PSA allows members of the public to browse the entire available archive via an FTP (File Transfer Protocol) interface, and also provides a Java-based Advanced Search Interface tool that lets a user specify dozens of search parameters, select datasets from search results, and it then “delivers” the requested datasets to a special folder on their server and sends the user an email containing a hypertext link to the data.Figure 1: Quick look analysis of SPICAV-UV data from VEX orbit 520.Datasets for the SPICAV instrument cluster are stored by spacecraft orbit number. Each individual dataset comes with human-readable descriptor files that define the format, encoding, and semantic meaning of all data provided. In addition to the spectral data themselves, the dataset also include all of the contextual data about the conditions under which the observations were made, such as spacecraft altitude and orientation, instrument temperature, the time and date, exposure times, instrument configuration settings, and many more.A SPICAV-UV dataset file includes one or more Collection objects, each containing a header descriptor and data table. A data table consists of five rows of 408 columns, which represents five rows of the CCD with each row containing 408 pixels. Each 16-bit pixel value is a digital representation of the charge collected by that pixel during integration.The PSA also provides a data browsing area on the FTP server where summary images of each dataset are available for a “quick look” at the data (see Figure 1).Science with SPICAVOne example of an investigation which used data from SPICAV-UV is a recent study hoping to find evidence of extant volcanic activity. Six years of ultraviolet spectrometer data were used to examine the density of sulphur dioxide above the clouds of Venus (Marcq et al. 2012). They found that SO2 column densities increased prior to 2007, and then decreased by a factor of 5 over the next five years. Read the rest of my summary of this research here.Another study a year earlier (Montmessin, et al. 2011) used SPICAV-UV data to identify, for the first time, a layer of ozone in the upper atmosphere of Venus (previously, ozone had only been identified in the atmospheres of Mars and Earth). Read more details here.ReferencesBertaux, J., Nevejans, D., Korablev, O., Villard, E., Quémerais, E., Neefs, E., Montmessin, F., Leblanc, F., Dubois, J., Dimarellis, E., Hauchecorne, A., Lefèvre, F., Rannou, P., Chaufray, J., Cabane, M., Cernogora, G., Souchon, G., Semelin, F., Reberac, A., Van Ransbeek, E., Berkenbosch, S., Clairquin, R., Muller, C., Forget, F., Hourdin, F., Talagrand, O., Rodin, A., Fedorova, A., Stepanov, A., Vinogradov, I., Kiselev, A., Kalinnikov, Y., Durry, G., Sandel, B., Stern, A., & Gérard, J. (2007). SPICAV on Venus Express: Three spectrometers to study the global structure and composition of the Venus atmosphere Planetary and Space Science, 55 (12), 1673-1700 DOI: 10.1016/j.pss.2007.01.016Esposito, L. W. (1984). Sulfur dioxide: Episodic injection shows evidence for active venus volcanism. Science (New York, N.Y.), 223(4640), 1072-1074.Marcq, E., Bertaux, J. L., Montmessin, F., & Belyaev, D. (2012). Variations of sulphur dioxide at the cloud top of Venus's dynamic atmosphere. Nature geoscience, 6(1), 25-28.Montmessin, F., Bertaux, J. L., Lefèvre, F., Marcq, E., Belyaev, D., Gérard, J. C., ... & Vandaele, A. C. (2011). A layer of ozone detected in the nightside upper atmosphere of Venus. Icarus, 216(1), 82-85.... Read more »
Bertaux, J., Nevejans, D., Korablev, O., Villard, E., Quémerais, E., Neefs, E., Montmessin, F., Leblanc, F., Dubois, J., Dimarellis, E.... (2007) SPICAV on Venus Express: Three spectrometers to study the global structure and composition of the Venus atmosphere. Planetary and Space Science, 55(12), 1673-1700. DOI: 10.1016/j.pss.2007.01.016
An atmospheric study using the SPICAV-UV instrument recently came to my attention where researchers (Montmessin, et al. 2011) used the data archive to identify (for the first time) a layer of ozone in the upper atmosphere of Venus (previously, ozone had only been identified in the atmospheres of Mars and Earth).The team analyzed the complete SPICAV dataset, and determined that UV absorption by O3 was observed during a stellar occultation run on the night side of Venus during orbit #348. They confirmed ozone detection in 28 additional orbits, and isolated the ozone to a discrete layer no more than 10 km thick near a mean altitude of 100km.The observed concentrations of 107 – 108 molecules per cubic centimeter are consistent with expected values if the upper atmosphere were dominated by the same chlorine-catalyzed destruction cycles present in Earth’s stratosphere.Even if the same mechanisms are at work in he Venusian atmosphere, the authors state that the observed ozone layer seems too tenuous to filter out UV radiation and provide protection to organisms that could have existed on Venus.Referenced:Montmessin, F., Bertaux, J., Lefèvre, F., Marcq, E., Belyaev, D., Gérard, J., Korablev, O., Fedorova, A., Sarago, V., & Vandaele, A. (2011). A layer of ozone detected in the nightside upper atmosphere of Venus Icarus, 216 (1), 82-85 DOI: 10.1016/j.icarus.2011.08.010... Read more »
Montmessin, F., Bertaux, J., Lefèvre, F., Marcq, E., Belyaev, D., Gérard, J., Korablev, O., Fedorova, A., Sarago, V., & Vandaele, A. (2011) A layer of ozone detected in the nightside upper atmosphere of Venus. Icarus, 216(1), 82-85. DOI: 10.1016/j.icarus.2011.08.010
In an effort to determine if conditions were ever right on Mars to sustain life, a team of scientists, including a Michigan State University professor, has examined a meteorite that formed on the red planet more than a billion years ago. And although this team’s work is not specifically solving the mystery, it is laying … Read More →... Read more »
Stopar, J., Taylor, G., Velbel, M., Norman, M., Vicenzi, E., & Hallis, L. (2013) Element abundances, patterns, and mobility in Nakhlite Miller Range 03346 and implications for aqueous alteration. Geochimica et Cosmochimica Acta, 208-225. DOI: 10.1016/j.gca.2013.02.024
Scientists have found a new dwarf galaxy, dubbed Leo P, near our Milky Way. This galaxy is present about five to six million light-years away from Milky Way.
The Astronomical Journal
Astronomers found this galaxy with Arecibo Observatory radio telescope in Puerto Rico and first considered it as a cloud of hydrogen gas. Later they confirmed the finding with optical telescopes at Kitt Peak National Observatory in Arizona.
Leo P is one of the lonely dwarf galaxies that are hard to be found due to their distance, faintness and presence as such galaxies can be found anywhere in the sky. This galaxy appears to be undisturbed by the gravitational pull of the nearby larger galaxies.
“It is a product of a sedate environment, away from major galaxies,” Riccardo Giovanelli of Cornell University, one of the founders of Leo P, said in a statement.
“Its properties are extreme: it is the lowest-mass system known that contains significant amounts of gas and is currently forming stars,” Researchers wrote.
The discovery of this new galaxy also points to the presence of the other galaxies.
“We have many dozens of these objects now,” Giovanelli says. “We’re going to see which we can pull out of the muck.”
Rhode, K., Salzer, J., Haurberg, N., Van Sistine, A., Young, M., Haynes, M., Giovanelli, R., Cannon, J., Skillman, E., McQuinn, K., & Adams, E. (2013). ALFALFA DISCOVERY OF THE NEARBY GAS-RICH DWARF GALAXY LEO P. II. OPTICAL IMAGING OBSERVATIONS The Astronomical Journal, 145 (6) DOI: 10.1088/0004-6256/145/6/149... Read more »
Rhode, K., Salzer, J., Haurberg, N., Van Sistine, A., Young, M., Haynes, M., Giovanelli, R., Cannon, J., Skillman, E., McQuinn, K.... (2013) ALFALFA DISCOVERY OF THE NEARBY GAS-RICH DWARF GALAXY LEO P. II. OPTICAL IMAGING OBSERVATIONS. The Astronomical Journal, 145(6), 149. DOI: 10.1088/0004-6256/145/6/149
Researchers have found a theoretical possibility that the speed of light may not be constant and it may change while interacting with the ephemeral particles in the vacuum.
European Physical Journal D
Researchers based their report on the findings related to vacuum. Vacuum is a space that was thought to be fully empty of matter but at the smallest and the most basic level of quantum physics, it is not empty as it is occupied with particle pairs such as electron-positron or quark-antiquark pairs that appeaar and disappear continuously with extremely short lifetimes.
In one study, researchers including Marcel Urban and his collagues from the University of Paris-Sud, located in Orsay, France, found “quantum level mechanism” to understand the vacuum and identified that the vacuum is not completely empty but it is filled with the virtual or ephemeral particles having various levels of energy.
Based on this finding of changing energy levels and vacuum fluctuation, researchers proposed that the speed of light may also change.
In another study, researchers including Gerd Leuchs and Luis L. Sánchez-Soto, from the Max Planck Institute for the Physics of Light in Erlangen, Germany, proposed that some of the physical constants, such as the so-called impedance of free space, (which shows the different levels of the electric and magnetic fields of electromagnetic radiation moving through the free space,) depends only on sum of the square of the electric charges of particles but not on their masses.
The value of vacuum impedance, which is important for the determination of the speed of light, combined with the value of the speed of light, shows the total number of charged elementary particles found in nature.
Both of the studies presented the concept of the interaction of the light with the virtual particle-antiparticle pairs thereby affecting the speed of light.
Springer, VOA, NBC News
Leuchs, G., & Sánchez-Soto, L. (2013). A sum rule for charged elementary particles The European Physical Journal D, 67 (3) DOI: 10.1140/epjd/e2013-30577-8
Urban, M., Couchot, F., Sarazin, X., & Djannati-Atai, A. (2013). The quantum vacuum as the origin of the speed of light The European Physical Journal D, 67 (3) DOI: 10.1140/epjd/e2013-30578-7... Read more »
Urban, M., Couchot, F., Sarazin, X., & Djannati-Atai, A. (2013) The quantum vacuum as the origin of the speed of light. The European Physical Journal D, 67(3). DOI: 10.1140/epjd/e2013-30578-7
Pulsar Tests Gravity
Because of their extremely high densities, massive neutron stars can be used to test gravity. Based on spectroscopy of its white dwarf companion, Antoniadis et al. (p. 448) identified a millisecond pulsar as a neutron star twice as heavy as the Sun. The observed binary’s orbital decay is consistent with that predicted by general relativity, ruling out previously untested strong-field phenomena predicted by alternative theories. The binary system has a peculiar combination of properties and poses a challenge to our understanding of stellar evolution.... Read more »
In the center of our Galaxy lies a region called the Central Molecular Zone (CMZ). This region is filled with gas and is forming stars at a rate of about 0.1 M☉ yr-1 — enough to qualify it as a starburst region (a region with an abnormally high star formation rate), but relatively modest when compared to very active star-forming regions we observe in places such as M82, which clocks in at a rate 100 times higher. Thus the author suggests the CMZ might serve as somewhat of a prototype for starburst regions and outflows.... Read more »
SUSANNA KOHLER. (2013) Blowing Bubbles from Our Galaxy. Astrobites. info:/
Astronomers have found that the gravitational waves are produced even in the spacetime when the two stars, in the extreme conditions, move around each other. This is the proof of the Einstein's gravity theory in the one of the most extreme conditions yet studied.
Einstein's general theory of relativity:
Gravity is the cause of the curvature of spacetime created by the presence of mass and energy, according to the Einstein's general theory of relativity. When two stars move around each other, gravitational waves are produced, energy of the binary system loses out, and the orbital period decreases as the stars come close together.
Pair of stars for experiment:
This test has been done on the PSR J0348 0432, which is one of the great celestial objects in terms of gravity. You can read the features of the binary stars below;
Features of the binary stars
PSR J0348 0432
Extraordinarily heavy neutron star that releases radio waves, which are detectable by the radio telescopes on Earth
Twice as heavy as the Sun but only 20km across
Spins 25 times in a second
White dwarf star
Light in weight
Orbiting around the massive star every two and a half hours that is an extraordinarily short period of time.
"The unusual pair of stars is quite interesting in its own right but we've learned it is also a unique laboratory for testing the limits of one of our most fundamental physical theories, general relativity" says University of Toronto astronomy professor Marten van Kerkwijk, a member of the research team.
What researchers found?
Researchers found a minute but considerable change in the orbital period of the binary, of eight-millionths of a second per year. In order to detect the changes, they used very precise timing of the pulsar's spin-modulated emission with radio telescopes. This shrinking orbit is according to the prediction of the general relativity.
This gives “further confidence that Einstein's theory is a good description of nature – even though we know it is not a complete one, given the unresolved inconsistencies with quantum mechanics." van Kerkwijk said in a statement.
"We really are just at the beginning of our studies of this massive and bizarre stellar object," Bonn PhD student John Antoniadis, said. "It may become the new standard for testing general relativity as time goes on."
Antoniadis, J., Freire, P., Wex, N., Tauris, T., Lynch, R., van Kerkwijk, M., Kramer, M., Bassa, C., Dhillon, V., Driebe, T., Hessels, J., Kaspi, V., Kondratiev, V., Langer, N., Marsh, T., McLaughlin, M., Pennucci, T., Ransom, S., Stairs, I., van Leeuwen, J., Verbiest, J., & Whelan, D. (2013). A Massive Pulsar in a Compact Relativistic Binary Science, 340 (6131), 1233232-1233232 DOI: 10.1126/science.1233232... Read more »
When galaxies form new stars, they sometimes do so in frantic episodes of activity known as starbursts. These events were commonplace in the early Universe, but are rarer in nearby galaxies. During these bursts, hundreds of millions of stars are born, and their combined effect can drive a powerful wind that travels out of the … Read More →... Read more »
Sanchayeeta Borthakur, Timothy Heckman, David Strickland, Vivienne Wild, & David Schiminovich. (2013) The Impact of Starbursts on the Circumgalactic Medium. The Astrophysical Journal. arXiv: 1303.1183v2
Astronomers have found such a planetary system orbiting the star Kepler-62. This five-planet system has two worlds in the habitable zone – the distance from their star at which they receive enough light and warmth for liquid water to theoretically exist on their surfaces. Modeling by researchers at the Harvard-Smithsonian Center for Astrophysics (CfA) suggests that both planets are water worlds, their surfaces completely covered by a global ocean with no land in sight.... Read more »
David A. Aguilar, & Christine Pulliam. (2013) Two Water Worlds for the Price of One. C f A Press Room. info:/
“WE’LL BE ABLE to see the beginning of the universe as we know it today,” says Charles Alcock, director of the Harvard-Smithsonian Center for Astrophysics (CfA) and professor of astronomy—imaging the radiation signatures from ancient galaxies billions of light years from his hilltop office on Garden Street, near the Radcliffe Quad. Addressing that same frontier, Abraham (Avi) Loeb, Baird professor of science and chair of the astronomy department, characterizes the research as “the scientific version of the story of Genesis.” Closer to home, so to speak, where the quest for “exoplanets” orbiting other stars has accelerated since the first discovery in 1995—and with it the search for chemical signs of life elsewhere—Wendy Freedman, chair and director of the Observatories of the Carnegie Institution for Science, in Pasadena, California, says, “We can now approach it from a scientific standpoint. It’s no longer science fiction.”... Read more »
John S. Rosenberg. (2013) Seeing Stars. Harvard Magazine. info:/
ESA’s Herschel space observatory has solved a long-standing mystery as to the origin of water in the upper atmosphere of Jupiter, finding conclusive evidence that it was delivered by the dramatic impact of comet Shoemaker-Levy 9 in July 1994.
During the spectacular week-long collision, a string of 21 comet fragments pounded into the southern hemisphere of Jupiter, leaving dark scars in the planet’s atmosphere that persisted for several weeks.... Read more »
Markus Bauer. (2013) Herschel links Jupiter’s water to comet impact. ESA Herschel. info:/
A few years ago, researchers revealed that the universe is expanding at a much faster rate than originally believed — a discovery that earned a Nobel Prize in 2011. But measuring the rate of this acceleration over large distances is still challenging and problematic, says Prof. Hagai Netzer of Tel Aviv University’s School of Physics and Astronomy. Now, Prof. … Read More →... Read more »
Wang, J., Du, P., Valls-Gabaud, D., Hu, C., & Netzer, H. (2013) Super-Eddington Accreting Massive Black Holes as Long-Lived Cosmological Standards. Physical Review Letters, 110(8). DOI: 10.1103/PhysRevLett.110.081301
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