"Raise your voice, not the sea level. Planet Earth is our shared island. Let us join forces to protect it."
- UN Secretary General Ban Ki-moon
Astronomers announced they have discovered a new type of planet - a rocky world weighing 17 times as much as Earth. This is big thing as theorists believed such a world couldn't form because anything so hefty would grab hydrogen gas as it grew and become a Jupiter-like gas giant. This planet, though, is all solids and much bigger than previously discovered "super-Earths" - making it a "mega-Earth". The planet is called Kepler-10c.
The newfound mega-Earth circles a sunlike star once every 45 days. It is located about 560 light-years from Earth in the constellation Draco. The system also hosts a 3-Earth-mass "lava world", Kepler-10b, in a remarkably fast, 20-hour orbit. Kepler-10c has 29000 km diameter - 2.3 times as large as Earth. This was known before and suggested it fell into a category of planets known as mini-Neptunes, which have thick, gaseous envelopes. Then HARPS-North instrument on the Telescopio Nazionale Galileo (TNG) in the Canary Islands measured the mass of Kepler-10c. They found that it weighed 17 times as much as Earth - far more than expected. This showed that Kepler-10c must have a dense composition of rocks and other solids.
Planet formation theories have a difficult time explaining how such a large, rocky world could develop. However, a new observational study suggests that it is not alone. CfA astronomer Lars A. Buchhave found a correlation between the period of a planet (how long it takes to orbit its star) and the size at which a planet transitions from rocky to gaseous. This suggests that more mega-Earths will be found as planet hunters extend their data to longer-period orbits. The discovery that Kepler-10c is a mega-Earth also has profound implications for the history of the universe and the possibility of life. The Kepler-10 system is about 11 billion years old, which means it formed less than 3 billion years after the Big Bang. The early universe contained only hydrogen and helium. Heavier elements needed to make rocky planets, like silicon and iron, had to be created in the first generations of stars. When those stars exploded, they scattered these crucial ingredients through space, which then could be incorporated into later generations of stars and planets. This process should have taken billions of years. However, Kepler-10c shows that the universe was able to form such huge rocks even during the time when heavy elements were scarce.
On a clear night, you might be able to spot the red dwarf star Gliese 832 through a backyard telescope, as it is just 16 light years away. Couple of days ago, astronomers announced the discovery of super-Earth planet orbiting this nearby star and say it might be the best candidate yet for habitable world. Gliese 832c was spotted by an international team of astronomers, led by Robert A. Wittenmyer from UNSW Australia. They used high-precision radial-velocity data from HARPS-TERRA, the Planet Finder Spectrograph and the UCLES echelle spectrograph. This star is already known to have one additional planet, a cold Jupiter-like planet, Gliese 832 b, discovered in 2009. Since red dwarf stars shine dimly, the habitable zones around these stars would be very close in. Gliese 832c complies with an orbital period of 36 days (it's orbital companion Gliese 832 b orbits the star in 9.4 years). The newly found super-Earth has a mass at least five times that of Earth's and the astronomers estimate it receives about the same average energy as Earth does from the Sun. The planet might have Earth-like temperatures, albeit with large seasonal shifts, given a similar terrestrial atmosphere. A denser atmosphere, something expected for Super-Earths, could easily make this planet too hot for life and a "Super-Venus" instead. Using the Earth Similarity Index (ESI) - a measure of how physically similar a planetary mass object is to Earth, where 1 equals the same qualities as Earth - Gliese 832 c has an ESI of 0.81. This is comparable to Gliese 667C c (ESI = 0.84) and Kepler-62 e (ESI = 0.83). This makes Gliese 832c one of the top three most Earth-like planets according to the ESI (i.e. with respect to Earth's stellar flux and mass) and the closest one to Earth of all three, a prime object for follow-up observations. However, other unknowns such as the bulk composition and atmosphere of the planet could make this world quite different to Earth and non-habitable. For more information, see [1406.5587] GJ 832c: A super-earth in the habitable zone.
As far back as 1948, Erwin Schrödinger - the inventor of modern quantum mechanics - published the book 'What is life?' In it, he suggested that quantum mechanics and coherent ringing might be at the basis of all biochemical reactions. At the time, this idea never found wide acceptance because it was generally assumed that vibrations in protein molecules would be too rapidly damped. Now, scientists have shown that he may have been on the right track after all. Using modern laser spectroscopy, the scientists have been able to measure the vibrational spectrum of the enzyme lysozyme, a protein that fights off bacteria. They discovered that this enzyme rings like a bell with a frequency of a few terahertz or a million-million hertz. Most remarkably, the ringing involves the entire protein, meaning the ringing motion could be responsible for the transfer of energy across proteins. The experiments show that the ringing motion lasts for only a picosecond or one millionth of a millionth of a second. Biochemical reactions take place on a picosecond timescale and the scientists believe that evolution has optimised enzymes to ring for just the right amount of time. Any shorter, and biochemical reactions would become inefficient as energy is drained from the system too quickly. Any longer and the enzyme would simple oscillate forever: react, unreact, react, unreact, etc. The picosecond ringing time is just perfect for the most efficient reaction. These tiny motions enable proteins to morph quickly so they can readily bind with other molecules, a process that is necessary for life to perform critical biological functions like absorbing oxygen and repairing cells. More information can be found here.
Not only that; scientists have discovered how algae that survive in very low levels of light are able to switch on and off a weird quantum phenomenon that occurs during photosynthesis. The function in the algae of this quantum effect, known as coherence, remains a mystery, but it is thought it could help them harvest energy from the sun much more efficiently. Working out its role in a living organism could lead to advances such as better organic solar cells. For details, see Single-residue insertion switches the quaternary structure and exciton states of cryptophyte light-harvesting proteins.
Einstein's theory of relativity envisions time as a spatial dimension, like height, width, and depth. But unlike those other dimensions, time seems to permit motion in only one direction: forward. This directional asymmetry - the "arrow of time" - is something of a conundrum for theoretical physics. But is it something we can see? An international group of computer scientists believes that the answer is yes. They have developed a new algorithm that can, with roughly 80 percent accuracy, determine whether a given snippet of video is playing backward or forward. While I do not underestimate this, I doubt computer scientists can fight what math and physics is telling us. Time is part of complex space geometry and position objects take. Approach taken here is applicable to specific and obvious (visually) situations only. Suppose that, in a video, a ball is rolling down a ramp and strikes a bump that briefly launches it into the air. When the video is playing in the forward direction, the sudden change in the ball's trajectory coincides with a visual artifact: the bump. When it's playing in reverse, the ball suddenly leaps for no reason. The researchers were able to model that intuitive distinction as a statistical relationship between a mathematical model of an object's motion and the "noise," or error, in the visual signal. Unfortunately, the approach works only if the object's motion can be described by a linear equation, and that's rarely the case with motions involving human agency. The algorithm can determine, however, whether the video it's being applied to meets that criterion. And in those cases, its performance is much better.
And now a little bit of particle physics - neutrinos. Neutrinos are tiny, neutral elementary particles that, contrary to the standard model of physics, have been proven to have mass. One possible explanation for this mass could be that neutrinos are their own antiparticles, so-called Majorana particles. Though experimental evidence for this is still lacking, many theoretical extensions of the standard model of physics predict the Majorana nature of neutrinos. If this hypothesis proves to be true, many previously unanswered questions about the origin of our universe and the origin of matter could be answered.
In the EXO-200 experiment (EXO: Enriched Xenon Observatory - Neutrinoless Double Beta Decay), which is operated in the US state of New Mexico, 650 meters below Earth's surface, scientists are looking for the evidence. The most sensitive method to experimentally verify the Majorana question is the search for a process called "neutrinoless double-beta decay". This process is a special radioactive decay that may only occur if neutrinos are their own antiparticles. The EXO-200 experiment has searched for these decays over several years. From the fact that not one of these decays has been detected, the scientists can now deduce a lower limit for the half-life of the decay of at least 1025 years - around one million-billion years more than the age of the universe. Although this measurement attains unprecedented accuracy, the question about the nature of neutrinos can still not be answered.
Neutrino oscillation is a phenomenon where neutrinos change from one flavor to another as they travel; it’s a purely quantum phenomenon. It has been observed in several contexts, including particle accelerators, nuclear reactors, cosmic rays hitting the atmosphere, and neutrinos traveling from our Sun. This is the first widely accepted phenomenon in particle physics that requires an extension to the Standard Model, the capstone of which was the observation of the Higgs boson at CERN. Neutrinos and neutrino oscillations represent the next stage of particle physics, beyond the Higgs.
If you're searching for something that may not exist, and can pass right through matter if it does, then knowing where to look is essential. That’s why the search for so-called sterile neutrinos is a process of elimination. Experiments like Fermilab’s MiniBooNE and the Liquid Scintillator Neutrino Detector (LSND) at Los Alamos National Laboratory have published results consistent with the existence of these theoretical particles. But a new result from the long-running MINOS experiment announced this week severely limits the area in which they could be found and casts more doubt on whether they exist at all. See Lubos Motl comment in The Reference Frame: MINOS disfavors nearly degenerate sterile neutrinos. MicroBooNE is on the way too - see Quantum Diaries.
And finally, NEMO (Neutrino Ettore Majorana Observatory) experiment, whose goal was to elucidate the nature of neutrinos and measure their mass, yielded very positive results. The observation, in seven different isotopes, of an extremely rare radioactive decay event, the so-called 'allowed' double-beta decay, helped improve our understanding of the atomic nucleus. In addition, the data collected during the search for the so-called 'forbidden' double-beta decay enabled the researchers to establish a range (0.3-0.9 eV) for the upper limit on the mass of the neutrino. For details, see Search for neutrinoless double beta decay with the NEMO-3 detector: first results.
For the first time, scientists from the CMS experiment CERN's LHC have succeeded in finding evidence for the direct decay of the Higgs boson into fermions. Previously, the Higgs particle could only be detected through its decay into bosons. We now know that the Higgs particle can decay into both bosons and fermions, which means we can exclude certain theories predicting that the Higgs particle does not couple to fermions. The researchers analyzed the data gathered at the LHC between 2011 and 2012, combining the Higgs decays into bottom quarks and tau leptons, both of which belong to the fermion particle group. The results reveal that an accumulation of these decays comes about at a Higgs particle mass near 125 GeV and with a significance of 3.8 sigma. This means that the probability of the background alone fluctuating up by this amount or more is about one in 14000. In particle physics, a discovery is deemed confirmed from a significance of five sigma.
New research published by CERN has brought us a step closer to understanding where all the antimatter has gone. This matter-antimatter asymmetry is one of the greatest challenges in physics and at this moment in time the universe seems to be composed entirely of matter - the only antimatter around is created by us at places like CERN. Yet our theories predict that exactly equal amounts of matter and antimatter would have been created in the Big Bang. So where did all the antimatter go?
This is the first time that the electric charge of an anti-atom has been measured to high precision. Measuring the electric charge of antihydrogen atoms is a way to study any subtle differences between matter and antimatter which could account for the lack of antimatter in the universe. The ALPHA experiment reports a measurement of the electric charge of antihydrogen atoms, finding it to be compatible with zero to eight decimal places. This is the first time that the charge of an anti-atom has been measured to high precision and confirms our expectation that the charges of its constituents, the positron and antiproton, are equal and opposite. Though the result is not surprising it is a fundamental test that matter and antimatter have equal and opposite electric charges. It is reassuring that nature behaves as expected. Antiparticles should be identical to matter particles except for the sign of their electric charge. So while the hydrogen atom is made up of a proton with charge +1 and an electron with charge -1, the antihydrogen atom consists of a charge -1 antiproton and a charge +1 positron. We know, however, that matter and antimatter are not exact opposites - nature seems to have a one-part in 10 billion preference for matter over antimatter. However, we don't know why. ALPHA achieves this by using a complex system of particle traps that allow antihydrogen atoms to be produced and stored for long enough periods to make detailed studies. Understanding the matter-antimatter asymmetry is one of the greatest challenges in physics today.
To measure the charge of antihydrogen, the ALPHA experiment studied the trajectories of antihydrogen atoms released from the trap in the presence of an electric field. If the antihydrogen atoms had an electric charge, the field would deflect them, whereas neutral atoms would be undeflected. The result, based on 386 recorded events, gives a value of the antihydrogen electric charge as (-1.3±1.1±0.4) × 10-8, the plus or minus numbers representing statistical and systematic uncertainties on the measurement. With the restart of CERN's accelerator chain getting underway, the laboratory's antimatter research programme is set to resume soon. Experiments including ALPHA-2, an upgraded version of the ALPHA experiment, will be taking data along with the ATRAP and ASACUSA experiments and newcomer AEGIS, which will be studying the influence of gravity on antihydrogen.
It's almost three months since a team of scientists announced it had detected polarised light from the afterglow of the Big Bang. But questions are still being asked about whether cosmic dust may have clouded their discovery. As the US astronomer Carl Sagan pointed out: "Extraordinary claims require extraordinary evidence." As much as there was excitement over the BICEP2 announcement, there were also many questions. At the heart of this heated discussion is something quite cold - cosmic dust.
The light from the Cosmic Microwave Background (CMB) has to pass through a lot of intervening material as it travels for nearly 14 billion years to reach our telescopes. Our galaxy, in particular the cold dust grains drifting within it, is a very important source of confusion when trying to understand just how much of the light hitting the telescope is from the CMB and how much from the stuff in the way. Think of trying to take a picture of a beautiful sunset in a sandstorm and you're getting close. How you account for dust in our galaxy is crucial. Do it wrong and you can mistake it for the signal you want to find. The best way to remove this dust from the signal is to map the sky in many frequencies (or colours) of light. The BICEP2 team only had one frequency available in a bid to maximise how sensitive a picture they could make. They then relied on other measurements of the dust to make up for this. ESA's Planck satellite is currently doing just this. Unfortunately, this data is not fully processed yet for general use.
So the BICEP2 team decided to estimate the amount of dust using theoretical models, as well as any data available at that time. One such measurement - and this is where things get messy - is a digitised powerpoint slide of a Planck work-in-progress map of the sky shown at a conference talk. This is certainly unusual and not to be encouraged (especially as it was preliminary analysis) but not necessarily cause to throw out the result. However, meticulous reanalysis of both the Planck picture and BICEP2 data by Princeton physicist Raphael Flauger show that BICEP2 has likely been overly optimistic about the level of contamination from the dust. For some misconceptions flying in currently, see Lubos's article titled Inflation and BICEP2: Steinhardt is missing the whole point. Some other reactions are from Peter Woit in his Smoking Gun No Longer Smoking, Matt Strassler in BICEP2′s Cosmic Polarization: Published, Reduced in Strength and Lubos Motl in BICEP2 gets published in PRL (and BICEP2 and PRL: journalists prove that they're trash as bonus).
Speaking of dust, astronomers have created a detailed three-dimensional map of the dusty structure of the Milky Way - the star-studded bright disc of our own galaxy - as seen from Earth’s northern hemisphere. For details, see 3D map shows dusty structure of the Milky Way.
In the new research, scientists from KCL (King's College London) have investigated what the BICEP2 observations mean for the stability of the Universe. To do this, they combined the results with recent advances in particle physics. Measurements of the Higgs boson have allowed particle physicists to show that our universe sits in a valley of the 'Higgs field', which describes the way that other particles have mass. However, there is a different valley which is much deeper, but our universe is preventing from falling into it by a large energy barrier. The problem is that the BICEP2 results predict that the universe would have received large 'kicks' during the cosmic inflation phase, pushing it into the other valley of the Higgs field within a fraction of a second. If that had happened, the universe would have quickly collapsed in a Big Crunch. So, this may be yet another indication BICEP2 results contain an error. If not, there must be some other - as yet unknown - process which prevented the universe from collapsing. Dome follow-up text can be found in Should BICEP2, Higgs have crushed the Universe?
- European aerospace group Airbus and French rocket-maker Safran are looking at jointly making next-generation launch rockets to compete with US firm SpaceX. Arianespace's mainstay launcher is the Ariane 5, a heavy rocket that is highly reliable but it has to carry two large satellites to be profitable, and this can cause delays. France and Germany, the major shareholders in Arianespace, have not been able to agree on strategy for the development of future rockets. Many analysts say the satellite market is evolving fast towards smaller rockets with single payloads, such as SpaceX's Falcon. France has supported developing by 2021 the Ariane 6, sketched as a low-cost flexible successor able to place a single payload of three to 6.5 tonnes into a geostationary slot. Meanwhile, a Russian startup Dauria Aerospace will launch several satellites in the coming weeks, the country's first private satellite constellation, to offer maritime monitoring services. Still, the test launch of Russia's newest rocket (Angara) ended in embarrassment on Friday as authorities were forced to abort the flight overseen by President Vladimir Putin due to a last-minute glitch.
- Previous studies have suggested that plant growth can be influenced by sound and that plants respond to wind and touch. Now, researchers at the University of Missouri, in a collaboration that brings together audio and chemical analysis, have determined that plants respond to the sounds that caterpillars make when eating plants and that the plants respond with more defenses.
- NASA said "Hello World" in space. They successfully beamed a high-definition video from the ISS to Earth using a new laser communications instrument.
- Couples are more likely to sleep in sync when the wife is more satisfied with their marriage. Results show that overall synchrony in sleep-wake schedules among couples was high, as those who slept in the same bed were awake or asleep at the same time about 75% of the time. When the wife reported higher marital satisfaction, the percent of time the couple was awake or asleep at the same time was greater. For more information, see Couples sleep in sync when the wife is satisfied with their marriage.
- Magnetic fields range from quadrillionths of a gauss in the cosmic voids of the universe, to several microgauss in galaxies and galaxy clusters (ordinary refrigerator magnets have magnetic fields of approximately 50 gauss). Stars like the sun measure thousands of gauss. Neutron stars, which are the extremely compact, burned out cores of dead stars, exhibit the largest magnetic fields of all, ones exceeding quadrillions of gauss. Now, astrophysicists have established that cosmic turbulence could have amplified magnetic fields to the strengths observed in interstellar space. For more information, see International Collaboration Replicates Amplification of Cosmic Magnetic Fields.
- Is this flop of the month? See Have Australians and their photons legitimized time travel?
- What seemed to be rock-solid assumptions about the nature of small asteroids may end in rubble or even a cloud of dust. New findings suggest small asteroids can be a flying cluster of rocks or a cloud of dust with a solid rock at its nucleus. For details, see Physical Properties of Near-Earth Asteroid 2011 MD.
- A new study of supermassive black holes at the centers of galaxies has found magnetic fields play an impressive role in the systems' dynamics. In fact, in dozens of black holes surveyed, the magnetic field strength matched the force produced by the black holes' powerful gravitational pull.
- An international team of scientists including a Virginia Tech physicist have discovered that winds blowing from a supermassive black hole in a nearby galaxy work to obscure observations and x-rays. For more information, see A fast and long-lived outflow from the supermassive black hole in NGC 5548.
- The discovery of three closely orbiting supermassive black holes in a galaxy more than four billion light years away could help astronomers in the search for gravitational waves. For details, check here.
- What is the largest black hole? See in The Largest Black Hole In the Known Universe. What about the smallest one? See The Smallest Black Hole in the Universe.
- Astronomers have discovered two new planets orbiting a very old star that is near to our own sun. One of these planets orbits the star at the right distance to allow liquid water to exist on its surface, a key ingredient to support life. Kapteyn's Star, named after the Dutch astronomer, Jacobus Kapteyn, who discovered it at the end of the 19th century, is the second fastest-moving star in the sky and belongs to the Galactic halo, an extended group of stars orbiting our Galaxy on very elliptical orbits. With a third of the mass of the Sun, this red-dwarf can be seen with an amateur telescope in the southern constellation of Pictor. More information can be found in Two planets orbit nearby ancient star.
- Dwarf galaxies that orbit the Milky Way and the Andromeda galaxies defy the accepted model of galaxy formation, and recent attempts to wedge them into the model are flawed, reports an international team of astrophysicists. The study pokes holes in the current understanding of galaxy formation and questions the accepted model of the origin and evolution of the universe. According to the standard paradigm, 23% of the mass of the universe is shaped by invisible particles known as dark matter. The model predicts that dwarf galaxies should form inside of small clumps of dark matter and that these clumps should be distributed randomly about their parent galaxy, but what is observed is very different. The dwarf galaxies belonging to the Milky Way and Andromeda are seen to be orbiting in huge, thin disk-like structures.
- The planets of our solar system come in two basic flavors, like vanilla and chocolate ice cream. We have small, rocky terrestrials like Earth and Mars, and large gas giants like Neptune and Jupiter. We're missing the astronomical equivalent of strawberry ice cream - planets between about one and four times the size of Earth. NASA's Kepler mission has discovered that these types of planets are very common around other stars. New research following up on the Kepler discoveries shows that alien worlds, or exoplanets, can be divided into three groups - terrestrials, gas giants, and mid-sized "gas dwarfs" - based on how their host stars tend to fall into three distinct groups defined by their compositions. Find more by reading here.
- Life in the universe might be even rarer than we thought. Recently, astronomers looking for potentially habitable worlds have targeted red dwarf stars because they are the most common type of star, composing 80 percent of the stars in the universe. But a new study shows that harsh space weather might strip the atmosphere of any rocky planet orbiting in a red dwarf's habitable zone. For details, see Space Weather May Doom Potential Life on Red-Dwarf Planets. On the other hand, there are some 100 million other places in the Milky Way galaxy that could support complex life, report a group of university astronomers in the journal Challenges. For details, see Assessing the Possibility of Biological Complexity on Other Worlds, with an Estimate of t… And while on the subject, do not miss excellent What does alien life look like?
- Turbulence we take for granted, but we know a little bit about it. From hurricanes to cream stirred into coffee, from the bumblebee's impossible flight to the vortices shearing off the end of airplane wings, turbulence is all around us. Yet we don't fully understand it. It's considered one of the greatest unsolved problems in classical physics. Recent research strengthens the idea that gravity can be treated as a fluid - which also means that fluids can be treated gravitationally. This gravity/fluid correspondence tells us that there is a way to use gravitational tools and gravitational intuition to take a fresh look at turbulence. For more details, see Turbulent Black Holes.
- Some interesting news about Phoebe in Cassini's Phoebe: A weird moon of Saturn.
- The paleoclimate record for the last ice age - a time 21,000 years ago called the "Last Glacial Maximum" (LGM) - tells of a cold Earth whose northern continents were covered by vast ice sheets. Chemical traces from plankton fossils in deep-sea sediments reveal rearranged ocean water masses, as well as extended sea ice coverage off Antarctica. Air bubbles in ice cores show that carbon dioxide in the atmosphere was far below levels seen before the Industrial Revolution.
- Was it humankind or climate change that caused the extinction of a considerable number of large mammals about the time of the last Ice Age? For almost 50 years, scientists have been discussing what led to the mass extinction of large animals (also known as megafauna) during and immediately after the last Ice Age. One of two leading theories states that the large animals became extinct as a result of climate change. There were significant climate changes, especially towards the end of the last Ice Age - just as there had been during previous Ice Ages - and this meant that many species no longer had the potential to find suitable habitats and they died out as a result. However, because the last Ice Age was just one in a long series of Ice Ages, it is puzzling that a corresponding extinction of large animals did not take place during the earlier ones. The other theory concerning the extinction of the animals is "overkill". Modern man spread from Africa to all parts of the world during the course of a little more than the last 100000 years. In simple terms, the overkill hypothesis states that modern man exterminated many of the large animal species on arrival in the new continents. This was either because their populations could not withstand human hunting, or for indirect reasons such as the loss of their prey, which were also hunted by humans. Researchers have carried out the first global analysis of the extinction of the large animals, and the conclusion is clear - humans are to blame. For details, see Global late Quaternary megafauna extinctions linked to humans, not climate change.
- David Evans has come up with interesting theory (see here and here). It is one more attempt to include sun as major climate player. Among many, Lubos Motl was one of the folks who had chance to review it in early stages - here are his comments: The Reference Frame: David Evans' notch-filter theory of the climate is infinitely fine-tuned. Some folks are even more foolish as seen in Global warming denial: Calgary billboard is laughably wrong.
- Title says it all - Arctic sea ice: Melt season is getting longer.
- Thwaites Glacier, the large, rapidly changing outlet of the West Antarctic Ice Sheet, is not only being eroded by the ocean, it's being melted from below by geothermal heat. For details, see Evidence for elevated and spatially variable geothermal flux beneath the West Antarctic Ice Sheet.
- Beneath the barren whiteness of Greenland, a mysterious world has popped into view. Using ice-penetrating radar, researchers have discovered ragged blocks of ice as tall as city skyscrapers and as wide as the island of Manhattan at the very bottom of the ice sheet, apparently formed as water beneath the ice refreezes and warps the surrounding ice upwards. The newly revealed forms may help scientists understand more about how ice sheets behave and how they will respond to a warming climate. For more information, see here. Speaking of Greenland, new research suggests that climate change may be contributing to warm-season melting in Greenland through a novel means: dust - see here. A new study suggests that a warming period more than 400,000 years ago pushed the Greenland ice sheet past its stability threshold, resulting in a nearly complete deglaciation of southern Greenland and raising global sea levels some 4-6 meters. For details, see here.
- A team of researchers, led by Wenju Cai of CSIRO Marine and Atmospheric Research, in Australia has published a paper in the journal Nature in which they report that 21 out of 23 climate models they ran indicated an increased frequency of Indian Ocean Dipole events over the next century. The increase, the team also reports, will be due to the continuation of global warming. For more details, check here.
- If you live in the central United States it may not have felt this way, but for the Earth overall, last month likely was the warmest May on record. For details, see The Home Planet Experiences its Warmest May on Record. Btw, nearly 33 percent of California is now considered to be in exceptional drought - the most intense category. And the situation may soon worsen further, according to the Drought Monitor report. See Watch California Dry Out Before Your Very Eyes for details.
- The "El Nino" phenomenon, which sparks climate extremes around the globe, is likely to take hold in the Pacific Ocean by the end of the year and could even do so within weeks, the UN said.
- Researchers have found that the deep ocean currents that move heat around the globe stalled or even stopped about 950,000 years ago, possibly due to expanding ice cover in the north. The slowing currents increased carbon dioxide storage in the ocean, leaving less in the atmosphere, which kept temperatures cold and kicked the climate system into a new phase of colder but less frequent ice ages, they hypothesize. For details, see Thermohaline circulation crisis and impacts during the mid-Pleistocene transition.
- New research in the journal Nature's Scientific Reports has provided a major new theory on the cause of the ice age that covered large parts of the Northern Hemisphere 2.6 million years ago. In short, researchers found there was a strengthening of the monsoon during global cooling, instead of the intense rainfall normally associated with warmer climates. The change in salinity encouraged sea ice to form which in turn created a change in wind patterns, leading to intensified monsoons. These provided moisture that caused an increase in snowfall and the growth of major ice sheets, some of which reached 3km thick. For longer version, see Pacific freshening drives Pliocene cooling and Asian monsoon intensification.
- Tom Yulsman has nice article about climate talk paradigm shift titled Have We Finally Learned How to Talk about Climate Change?
- Which came first: life or habitability? Although this question seems at first sight contradictory, a new paper by Colombian researchers is bringing to the attention of astrobiologists a classical conundrum: Is life also required for habitability? On Earth it is almost a matter of fact that in the same way as habitable conditions on our planet are mandatory for life, the existence of life could also be determinant at making our world permanently habitable. And, if this is the case for Earth, it should be also for other inhabited habitable planets elsewhere. Consequently, if our goal is to find life in the Universe, we should not exclude life itself when predicting on which planets it could thrive. For details, see [1405.4576] The Habitable Zone of Inhabited Planets.
- In a discovery decades in the making, scientists have detected the first of a 'theoretical' class of stars first proposed in 1975 by physicist Kip Thorne and astronomer Anna Zytkow. Thorne-Zytkow objects are hybrids of red supergiant and neutron stars that superficially resemble normal red supergiants, such as Betelguese in the constellation Orion. They differ, however, in their distinct chemical signatures that result from unique activity in their stellar interiors. For more information see Astronomers discover first Thorne-Żytkow object, a bizarre type of hybrid star.
- A new series of measurements of oxygen isotopes provides increasing evidence that the moon formed from the collision of the Earth with another large, planet-sized astronomical body, around 4.5 billion years ago. More information can be found in Identification of the giant impactor Theia in lunar rocks. Speaking of which, make sure you read The Moon's two faces: Why are they so different?
- Funny Stephen Hawking interview - must see!
- Researchers show for the first time that sleep after learning encourages the growth of dendritic spines, the tiny protrusions from brain cells that connect to other brain cells and facilitate the passage of information across synapses, the junctions at which brain cells meet. For more information, see here.
- See Lubos Motl take on new physics in The Reference Frame: New physics? LHCb insists on a flavor anomaly in \(B\) decays.
- For decades, physicists have searched in vain for exotic bound states comprising more than three quarks. Experiments have now shown that, in fact, such complex particles do exist in nature. The measurements confirm first results from 2011 for the existence of an exotic dibaryon made up of six quarks. Whether all six quarks form a single compact entity or rather a "hadronic molecule" has yet to be clarified. The latter would be composed of several nuclear building blocks - for example of excited protons and neutrons bound to each other - yet much more strongly than inside an atomic nucleus.
- Sascha Vongehr made nice article titled Answer To Where Are The Parallel Worlds. He also made nice arxiv paper available as [1311.5419] Against Absolute Actualization: Three "Non-Localities" and Failure of Model-External Randomness made easy w…
- Find yourself 20 minutes of fee time and check Back to Earth: How astronauts get back from the space station (VIDEO).
- Sabine Hossenfelder made another video.
- Potentially good news for SUSY - see The Reference Frame: Stops at \(200\GeV\), a \(W^+W^-\) anomaly may be screaming.
- Do you know what draa is? Check Let's Go Get Duned. Or More Precisely, Draaed — on Mars!
- Cool music video based on optical illusions and brought by Phil Plait in OK Go video: Illusions fill "The Writing's on the Wall."
- Remember story about ATLAS "Find the Higgs" contest and Lubos Motl joining in? He is 3rd at the time of this writing - see Leaderboard - Higgs Boson Machine Learning Challenge. Here is what Lubos has to say: Basics of the ATLAS contest and The ATLAS race: conquering K2 for the first time.
- Fan of Doctor Who? Then you must read Relativity: An explanation via Doctor Who.
- Using computer models, researchers found that as water freezes it takes on a sort of split personality wherein, at very cold temperatures and above a certain pressure, it may spontaneously split into two liquid forms. Finding this dual nature could lead to a better understanding of how water behaves in high-altitude clouds, which could improve the predictive ability of current weather and climate models. For details, see here.
- At several times in Earth’s history, mass extinctions have come close to wiping life out altogether. The reasons for these catastrophes are still unclear - they've been blamed on everything from asteroid impacts to cosmic ray blasts. But a new study has found that our planet itself could have a surprising hand in these disasters. For details, check Earth’s Magnetic Flips May Have Triggered Mass Extinctions.
- An historic milestone in artificial intelligence set by Alan Turing - the father of modern computer science - has been achieved. The 65 year-old iconic Turing Test was passed for the very first time by supercomputer Eugene Goostman during Turing Test 2014 held at the Royal Society in London on June 7, 2014. 'Eugene', a computer program that simulates a 13-year-old boy, managed to convince 33% of the human judges that it was human.
- Our ability to make choices - and sometimes mistakes - might arise from random fluctuations in the brain's background electrical noise, according to a recent study. New research shows how arbitrary states in the brain can influence apparently voluntary decisions.
- A new study identifies a newly discovered 3- to 5- million-year-old Tibetan fox from the Himalayan Mountains, Vulpes qiuzhudingi, as the likely ancestor of the living Arctic fox (Vulpes lagopus), lending support to the idea that the evolution of present-day animals in the Arctic region is intimately connected to ancestors that first became adapted for life in cold regions in the high altitude environments of the Tibetan Plateau. For more details, see New paper suggests High Tibet was cradle of evolution for cold-adapted mammals
- NASA is returning to the bottom of the ocean. Twice this summer, aquanauts participating in the NASA Extreme Environment Mission Operations (NEEMO) will conduct activities on the ocean floor that will inform future ISS and exploration activities. These studies provide information that correlates directly to life aboard the space station, where crew members must frequently perform critical tasks that present constraining factors similar to those experienced in an undersea environment. For more details, see NASA Announces Two Upcoming Undersea Missions.
- Three NASA science instruments aboard the ESA's Rosetta spacecraft, which is set to become the first to orbit a comet and land a probe on its nucleus, are beginning observations and sending science data back to Earth.
- Geochemists from the University of Lorraine in Nancy, France have discovered an isotopic signal which indicates that previous age estimates for both the Earth and the Moon are underestimates. Looking back into "deep time" it becomes more difficult to put a date on early Earth events. In part this is because there is little "classical geology" dating from the time of the formation of the Earth – no rock layers, etc. So geochemists have had to rely on other methods to estimate early Earth events. One of the standard methods is measuring the changes in the proportions of different gases (isotopes) which survive from the early Earth. New results show that the timing of the giant impact between Earth's ancestor and a planet-sized body occurred around 40 million years after the start of solar system formation. This means that the final stage of Earth's formation is around 60 million years older than previously thought.
- The first set of high-resolution results from ESA's three-satellite Swarm constellation reveals the most recent changes in the magnetic field that protects our planet. Launched in November 2013, Swarm is providing unprecedented insights into the complex workings of Earth's magnetic field, which safeguards us from the bombarding cosmic radiation and charged particles. Measurements made over the past six months confirm the general trend of the field's weakening, with the most dramatic declines over the Western Hemisphere. For details, please see Swarm reveals Earth’s changing magnetism.
- What if it were possible to measure your conscious experience, in real time, using a brain scanner? Neuroscientists Christoph Reichert and colleagues report that they have done just this, using fMRI - although in a limited fashion. For details, see Tracking Conscious Perception in Real-Time With fMRI? Meanwhile, a controlled study using functional MRI brain imaging reveals a possible biological link between early musical training and improved executive functioning in both children and adults, report researchers. The study uses functional MRI of brain areas associated with executive function, adjusting for socioeconomic factors. For details, see PLOS ONE: Behavioral and Neural Correlates of Executive Functioning in Musicians and Non-Musicians.
- Researchers report evidence for potentially oceans worth of water deep beneath the United States. Though not in the familiar liquid form -- the ingredients for water are bound up in rock deep in the Earth's mantle -- the discovery may represent the planet's largest water reservoir. The researchers have found deep pockets of magma located about 400 miles beneath North America, a likely signature of the presence of water at these depths. For details, see Dehydration melting at the top of the lower mantle.
- Astronomers may have identified what may be the smallest known star. And not just the smallest known star but quite possibly the smallest possible star. If it were any smaller, it might not even be a star anymore. For details, see The brown dwarf limit: Astronomers have found the smallest star known.
- The temperature increases by 30 ºC for every kilometre further underground. This thermal gradient, generated by the flow of heat from the inside of the Earth and the breakdown of radioactive elements in the crust, produces geothermal power. Around 500 power stations around the world already use it to generate electricity, although there are yet to be any in Spain. However, the subsoil of the Iberian Peninsula has the capacity to produce up to 700 gigawatts if this resource was exploited with enhanced geothermal systems (EGS) at a depth of between 3 and 10 kilometres, where the temperatures exceed 150 ºC. This is confirmed in the study now. For details, see here.
- A 3D printer intended for the International Space Station has passed its NASA certifications with flying colors—earning the device a trip to space sooner than expected. The next Dragon spacecraft, scheduled to launch in August, will carry the Made In Space printer on board.
- The solar wind of particles streaming off the sun helps drive flows and swirls in space as complicated as any terrestrial weather pattern. Scientists have now spotted at planet Mercury, for the first time, a classic space weather event called a hot flow anomaly, or HFA, which has previously been spotted at Earth, Venus, Saturn and Mars. Planets have a bow shock the same way a supersonic jet does. These hot flow anomalies are made of very hot solar wind deflected off the bow shock.
- Where volcanoes meet glaciers, lakes often form. This happens in many places on Earth and in at least one place off it: Arsia Mons, Mars. Arsia Monsis one of the largest mountains in the solar system. Wispy water-ice clouds gather near its peak during the Martian afternoon. While it is only the third tallest volcano on Mars, Arsia Mons is 300 km wide and twice as tall as Mount Everest. If Mount Everest were to suddenly erupt today, some of the vast glaciers on its surface would melt producing floods, lakes and debris plains. We now have reason to believe this is exactly what happened on Mars when Arsia Mons was active 200 million years ago. For some details, see Volcano–ice interactions in the Arsia Mons tropical mountain glacier deposits.
- Confirming what neurocomputational theorists have long suspected, researchers report that the human brain locks down episodic memories in the hippocampus, committing each recollection to a distinct, distributed fraction of individual cells. For more details, see Sparse and distributed coding of episodic memory in neurons of the human hippocampus.
- New research indicates that ultraviolet photons emitted by the sun likely cause water molecules on the lunar surface to either quickly desorb or break apart. The fragments of water may remain on the lunar surface, but the presence of useful amounts of water on the sunward side is not likely. For more details, see Solar photons drive water off the moon.
- Europe's powerful Milky Way mapper Gaia is facing some problems as controllers ready the Gaia telescope for operations. It turns out that there is "stray light" bleeding into the telescope, which will affect how well it can see the stars around it. Also, the telescope optics are also not transmitting as efficiently as the design predicted. Some more details can be found in Preliminary analysis of stray light impact and strategies.
- Astronomers have found that Jupiter's Galilean satellites (Io, Europa, Ganymede, and Callisto) remain slightly bright (up to one millionth of their normal state) even when in the Jovian shadow and not directly illuminated by the Sun. The effect is particularly pronounced for Ganymede and Callisto.
- Some nice things to know: Throwback Thursday: How Quantum Levitation Works, The Earth’s Analemma, The Cosmic Chronicle of Carbon-14, Decaying Gravitational Orbits and Dating the Distant Universe.
- Scientists at NASA's Jet Propulsion Laboratory have been working on a device that may one day explore the underside of ice on Europa, Jupiter's moon. NASA completed an early prototype of the rover it hopes will give us more information about Europa, with its abundant water and energy and chemistry. A National Geographic video below shows the rover, called BRUIE (Buoyant Rover for Under-Ice Exploration) being taken for a run in Alaska. The team is interested in Europa, with its frozen, fissured surface and all. NASA's notes on Europa tell us it is an icy world slightly smaller than Earth's moon. A unique feature about Europa in the solar system is its global ocean of water in contact with a rocky seafloor. According to NASA, Europa could be a promising place to look for life beyond Earth. Europa's surface is mostly solid water ice, extremely smooth and crisscrossed by fractures.
- In the past years, invisibility cloaks were developed for various senses. Objects can be hidden from light, heat or sound. However, hiding of an object from being touched still remained to be accomplished. Scientists have now succeeded in creating a volume in which an object can be hidden from touching similar to a pea under the mattress of a princess. For details, please see here and Cloaking Material Makes Objects Imperceptible to Touch.
- NASA has selected 18 proposals for studies under the Asteroid Redirect Mission Broad Agency Announcement (BAA). These six-month studies will mature system concepts and key technologies and assess the feasibility of potential commercial partnerships to support the agency's Asteroid Redirect Mission, a key part of the agency's stepping stone path to send humans to Mars. For more information about NASA's Asteroid Initiative and the Asteroid Redirect Mission, visit NASA - Asteroid Retrieval Initiative.
- Astronomers have discovered a bright, mysterious geologic object - where one never existed - on Cassini mission radar images of Ligeia Mare, the second-largest sea on Saturn’s moon Titan. Scientifically speaking, this spot is considered a "transient feature", but the astronomers have playfully dubbed it "Magic Island". Astronomers speculate on four reasons for this phenomenon:
- Northern hemisphere winds may be kicking up and forming waves on Ligeia Mare. The radar imaging system might see the waves as a kind of "ghost" island.
- Gases may push out from the sea floor of Ligeia Mare, rising to the surface as bubbles.
- Sunken solids formed by a wintry freeze could become buoyant with the onset of warmer temperatures during the late Titan spring.
- Ligeia Mare has suspended solids, which are neither sunken nor floating, but act like silt in a terrestrial delta.
For more details, see Mysterious 'Magic Island' appears on Saturn moon. Interesting enough, a combined NASA and ESA-funded study has found firm evidence that nitrogen in the atmosphere of Saturn's moon Titan originated in conditions similar to the cold birthplace of the most ancient comets from the Oort cloud. The finding rules out the possibility that Titan's building blocks formed within the warm disk of material thought to have surrounded the infant planet Saturn during its formation.
- Astronomers have identified possibly the coldest, faintest white dwarf star ever detected. This ancient stellar remnant is so cool that its carbon has crystallized, forming - in effect - an Earth-size diamond in space. The object in this new study is likely the same age as the Milky Way, approximately 11 billion years old. The researchers calculated that the white dwarf would be no more than a comparatively cool 2700 degrees Celsius. Our Sun at its center is about 5000 times hotter. For details, see A 1.05 M ☉ Companion to PSR J2222–0137: The Coolest Known White Dwarf?
- The Malaspina Expedition, led by the Spanish National Research Council, has demonstrated that there are five large accumulations of plastic debris in the open ocean that match with the five major twists of oceanic surface water circulation. In addition to the known accumulation of plastic waste in the North Pacific, there are similar accumulations in the central North Atlantic, the South Pacific, the South Atlantic and the Indian Ocean. For more details, see Plastic debris in the open ocean.
- The evolution of the ribosome, a large molecular structure found in the cells of all species, has been revealed in unprecedented detail in a new study.
- A University of Colorado Denver study examining collisions between bicycles and motorists, shows bicyclist safety significantly increases when there are more bikes on the road, a finding that could be attributed to a "safety in numbers effect".
- Scientists have discovered a new peculiarity of the Martian atmosphere. The scientists had analyzed satellite-acquired data and concluded that the dust particles in the planet's atmosphere can be of two types or modes. The first - coarser - mode is represented by both H2O ice grains with the average radius of 1.2 μm, and slightly smaller dust particles (R = 0.7 μm). The second mode is a lot finer, it is an aerosol which consists of much smaller particles with a radius of 0.04-0.07 μm. Interestingly, the density number of the both modes is not that high. Even in the most "dusty" layers of the planet's atmosphere at altitudes of 20-30 km there are about 3000 particles of the finer mode per 1 cm³, and not more than 2 particles of the coarser mode per 1 cm³. If compared with what is considered the norm on Earth, the air with such dust density is rather clean (rooms are usually a lot dustier); yet, aerosols are important because they, according to the scientists, play a key role in forming the planet's climate. Because of fine dust particles in the higher layers of the atmosphere, ice "embryos" are formed faster, which, in turn, influences clouds' build-up. The clouds are responsible for both precipitation and temperature condition on the planet's surface. Analyzing the way the dust is spread in the atmosphere of the planet with regard to the altitude and geographical coordinates is crucial for forming the full picture of what is happening on Mars. Besides that, the dust modes which the scientists have discovered confirm that Martian dust storms ("dust devils") are able to lift large quantities of substance from the planet's surface.
- Just like on Earth, the sun has spells of bad weather, with high winds and showers of rain. But unlike storms on Earth, rain on the sun is made of electrically charged gas (plasma) and falls at around 200000 kilometers an hour from the outer solar atmosphere, the corona, to the sun's surface. Now a team of solar physicists has pieced together an explanation for this intriguing phenomenon with imagery that shows a 'waterfall' in the atmosphere of the sun. Fore more details, see When it rains, it pours… on the Sun.
- Curiosity says hello and moves further according to plan...
- The first images taken by the Dark Energy Survey (DES) after the survey began in August 2013 have revealed a rare, "superluminous" supernova that erupted in a galaxy 7.8 billion light years away. The stellar explosion, called DES13S2cmm, easily outshines most galaxies in the Universe and could still be seen in the data six months later, at the end of the first of what will be five years of observing by DES. For more details, see here.
- Nearly 100 years since Albert Einstein developed General Relativity, the theory has passed its toughest test yet in explaining the properties of observable Universe. The most precise measurements to date of the strength of gravitational interactions between distant galaxies show perfect consistency with General Relativity’s predictions. For details, see [1312.4899] The Clustering of Galaxies in the SDSS-III Baryon Oscillation Spectroscopic Survey (BOSS): measuring growth…
- Astronomers using ESA and NASA high-energy observatories have discovered a tantalising clue that may hint dark matter. Galaxy clusters not only contain hundreds of galaxies, but also a huge amount of hot gas filling the space between them. However, measuring the gravitational influence of such clusters shows that the galaxies and gas make up only about a fifth of the total mass - the rest is thought to be dark matter. The gas is mainly hydrogen and, at over 10 million degrees celsius, is hot enough to emit X-rays. Traces of other elements contribute additional X-ray 'lines' at specific wavelengths. Examining observations by ESA's XMM-Newton and NASA's Chandra spaceborne telescopes of these characteristic lines in 73 galaxy clusters, astronomers stumbled on an intriguing faint line at a wavelength where none had been seen before. If this strange signal had been caused by a known element present in the gas, it should have left other signals in the X-ray light at other well-known wavelengths, but none of these were recorded. The astronomers suggest that the emission may be created by the decay of an exotic type of subatomic particle known as a 'sterile neutrino', which is predicted but not yet detected. (Ordinary neutrinos are very low-mass particles that interact only rarely with matter via the so-called weak nuclear force as well as via gravity. Sterile neutrinos are thought to interact with ordinary matter through gravity alone, making them a possible candidate as dark matter)
- The hunt for dark matter has taken another step forward thanks to new supercomputer simulations showing the evolution of our 'local Universe' from the Big Bang to the present day. For details, see “Cosmic own goal” another clue in hunt for dark matter.
- A researcher with the Department of Electrodynamics of Complex Systems and Nanophotonics, Alexander Rozhkov, has presented theoretical calculations which indicate the possible existence of fermionic matter in apreviously unknown state – in the form ofaone-dimensional liquid, which cannot be described within the framework of existing models. Details are contained in Rozhkov's article One-Dimensional Fermions with neither Luttinger-Liquid nor Fermi-Liquid Behavior.
- Physicist James Franson of the University of Maryland has apparently "captured the attention of the physics community" by posting an article to the peer-reviewed New Journal of Physics in which he claims to have found evidence that suggests the speed of light as described by the theory of general relativity, is actually slower than has been thought. More information in Apparent correction to the speed of light in a gravitational potential. Needless to say, I don't buy it.Needless to say, not the only one - see Franson's "breakthrough" concerning the speed of light.
- Why do the astronauts float around as if there's no gravity? Well, there is gravity and they float due to free fall of course. See Zero Gravity: It May Not Be What You Think.
- Nice read at The science that stumped Einstein.
- Rant of the month goes to Many worlds pseudoscience, again
- Planetary scientists have successfully used the Hubble Space Telescope to find two Kuiper Belt objects for NASA's New Horizons mission to Pluto. After the marathon probe zooms past Pluto in July 2015, it will travel across the Kuiper Belt - a vast rim of primitive ice bodies left over from the birth of our solar system 4.6 billion years ago. If NASA approves, the probe could be redirected to fly to a Kuiper Belt object and photograph it up close. For more details, see Hubble to Proceed with Full Search for New Horizons Targets.
- Tommaso Doringo reports of Not Only Top Quark: Bottom Quark Asymmetry Measured By CDF!
- A team of researchers in Europe has come up with a new way to determine the gravitational constant G. Rather than relying on using torque based techniques to measure gravitational pull, the researchers instead attempted to measure the attraction between a cloud of cold rubidium atoms and tungsten weights. They came up with a value for G of 6.67191(99) x 10^-11 m3 kg^1 s^2. More details here.
- Physicists found a way to boot up quantum computers 72 times faster than previously possible. For details, see Phys. Rev. Lett. 112, 240503 (2014) - Adaptive Hybrid Optimal Quantum Control for Imprecisely Characterized Systems.
- Nice picture of The Psychedelic Sun.
- Peter Woit has his view on string theory conference String 2014 - see Strings 2014 and String Theory Visions. Lubos Motl shortly jumped in with Strings 2014: talks
- NASA has tested new technology designed to bring spacecraft - and one day even astronauts - safely down to Mars, with the agency declaring the experiment a qualified success even though a giant parachute got tangled on the way down.
- It has been a decade since a robotic traveler from Earth first soared over rings of ice and fired its engine to fall forever into the embrace of Saturn. On June 30, the Cassini mission will celebrate 10 years of exploring the planet, its rings and moons. See Cassini’s 10th anniversary: The mission’s greatest images of Saturn.
- Pluto, now classified as a dwarf planet, has a moon, Charon, almost 1/8th its own mass and almost half its physical volume. Our Moon, by comparison, has about 1% of the Earth's mass and only 2% of its volume. Charon is so large compared to Pluto that some astronomer's consider the two to be a sort of binary dwarf-planet system, as opposed to a moon-and-planet system. Is there evidence of an ocean-past or present-waiting to surprise us on Charon? It isn't impossible. In fact, it might be likely. Why? Check More than Only Skin Deep - What Waits Beneath Charon’s Cracked Surface.
- For the end, this is something not to missed and title says it all - Stunning Night Sky Images. Enjoy!