Scientists meeting in Stockholm say they’ve confirmed that subatomic particles known as neutrinos have the ability to morph from one type of the particle into another. The finding could one day help scientists explain why the universe contains matter but very little antimatter.
Neutrinos, one of the fundamental building blocks of matter, come in three distinct types or flavors: electron, muon or tau. These particles have no electrical charge but their mass can vary by flavor. An electron neutrino has a mass no greater than 2.2 eV (electron volts). The muon neutrino can have a mass that is less than 170 KeV (kilo-electron volts). The tau neutrino, which has a mass of less than 15.5 MeV (mega-electron volts), was discovered in 2000 at the US Department of Energy’s Fermilab near Chicago.
Scientists produced a beam of muon neutrinos at the Japan Proton Accelerator Research Complex (J-PARC) near Japan’s east coast and aimed it at the gigantic Super-Kamiokande underground detector in Kamioka, 295 km away, near Japan’s west coast. They discovered that some of the muon neutrinos had morphed into electron neutrinos somewhere along the journey.
Physicists know these three different neutrino flavors have the ability to freely change from one type into another through a phenomenon called neutrino oscillations. However, the new findings made by the T2K (Tokai to Kamioka) team, mark the first discovery of electron neutrinos showing up in a beam of muon neutrinos.
“Understanding the properties of neutrinos in more detail would give an important clue to solving the riddle of how the universe has come to exist,” Takashi Kobayashi, a member of the T2K team, told the Japan News.
This new way of observing neutrino oscillation is the key for scientists to be able to make measurements that would allow them to distinguish the different oscillations of neutrinos and its anti-particle counterpart anti-neutrinos. This is something that could help in better understanding the physical processes that involve matter and antimatter.
“We have seen a new way for neutrinos to change, and now we have to find out if neutrinos and anti-neutrinos do it the same way,” said Professor Dave Wark, who helped lead the international T2K experiment. “If they don’t, it may be a clue to help solve the mystery of where the matter in the universe came from in the first place. Surely answering that is worth a couple of decades of work.”
New fallen snow on a crisp winter morning can be a beautiful and inspiring sight. But astronomers using the new Atacama Large Millimeter/submillimeter Array (ALMA) in Chile got really got a real thrill recently when they saw and imaged a snow fall in a very young solar system some 175 light years from Earth.
The astronomers say that this never-before-seen icy feature may play an important role in providing scientists with insight into the chemical make-up and the way that both comets and developing planets take shape.
Up until now, these alien snow lines have never been directly imaged and could only be spotted by their spectral signatures – a specific pattern of electromagnetic radiation that is used to identify a chemical or compound.
In a study published yesterday in Science Express, the authors speculate that the solar system where they found the deep space snow line surrounds a young star called TW Hydrae and that this solar system has many of the same characteristics that our own did when it was only a few million years old.
According to the research team’s co-leader, Chunhua “Charlie” Qi, from the Harvard-Smithsonian Center for Astrophysics in Cambridge, Mass, “ALMA has given us the first real picture of a snow line around a young star, which is extremely exciting because of what it tells us about the very early period in the history of our own Solar System. We can now see previously hidden details about the frozen outer reaches of another solar system, one that has much in common with our own when it was less than 10 million years old.”
Here on Earth snow lines that can often be seen near the summit of mountains are usually formed when freezing or sub-freezing temperatures, that are common at high elevations, turn atmospheric water vapor into snow.
The astronomers said that the snow lines found in the outer reaches of young solar systems are formed pretty much the same way as they do on Earth. But instead of simply water vapor freezing and turning into ice and snow like here on Earth, the scientists said that the frozen material found in the distant solar system are formed when gases such as methane, carbon dioxide and carbon monoxide form layers and freeze around grains of interplanetary dust.
They add that even more unusual molecules can also freeze and turn into snow and ice, depending how far the materials are from its star. Also, molecules like carbon monoxide are able to freeze a lot easier when they’re insulated by a surrounding fog of concentrated dust and gas.
It’s that insulation that surrounds the frozen matter that has kept scientists from getting a good look, until now, at the icy element hidden inside.
“It would be like trying to find a small, sunny patch hidden within a dense fogbank,” said the research team’s other co-leader Karin Oberg, from Harvard University and the University of Virginia in Charlottesville.
The astronomers behind this discovery said that they were able to poke through that insulating fog of gas by looking for molecules known diazenylium or N2H+, which can be spotted at great distances by a sensitive and advanced radio telescope like ALMA. Since the substance doesn’t survive when it’s in the presence of carbon monoxide – CO, the researchers came to realize that finding the fragile molecule would indicate that the carbon monoxide gas surrounding it was frozen.
“Using this technique, we were able to create, in effect, a photonegative of the CO snow in the disk surrounding TW Hydrae,” said Oberg. “With this we could see the CO snow line precisely where theory predicts it should be — the inner rim of the diazenylium ring.”
Snow lines, like the one found in the TW Hydrae solar system, are believed by astronomers to play an important part in the formation of a solar system.
They say that the frozen material surrounding the grains of planet-and-comet-forming dust provides it with a sticky coating which prevents the particles from self-destructing by smashing into each other. Scientists also theorize that the ice-covered dust grains help increase the amount of solids available and may dramatically speed up the planet formation process.
Since many different kinds of snow lines have been found, each variety may be linked to the formation of specific kinds of planets, according to the research team.
For example, in our own solar system a snow line formed from water could be located where Jupiter currently orbits the Sun and a snow line made from carbon monoxide would correspond to the Neptune’s solar orbit. They also speculate that an area of space where the snow line transitions to one made from CO could also denote the beginning of a region within a solar system where smaller icy bodies such as dwarf planets like Pluto as well as comets would develop.
The scientists said that they found CO snow lines especially interesting, since ice made with carbon monoxide is an important ingredient in making methanol or methol-alcohol, which they say is an element of more complex organic molecules essential for the formation of life. They think that comets and asteroids could then transport these molecules to developing Earth-like planets and seed them with the components that would help foster life.
Over the past several years, NASA spacecraft studying the sun have sent back some spectacular images of it exploding with solar flares and coronal mass ejections. Now, scientists say that two of these spacecraft — the Solar Dynamics Observatory (SDO) and the Reuven Ramaty High Energy Solar Spectroscopic Imager (RHESSI) — have detected a phenomenon called magnetic reconnection, what they describe as the ‘Heart of Space Weather’ in action.
NASA describes magnetic reconnection as something that takes place whenever the sun’s magnetic field lines first unite, arch out, break apart, reconnect with different magnetic fields, then snap into new positions, releasing a pulse of magnetic energy along the way. Scientists believe that the magnetic reconnection process is what’s behind enormous explosions on the sun that can hurl radiation and various energy related particles across the entire solar system.
If they could get a better understanding of this process, the scientists say, they may be able to develop new methods that would allow for much more advanced and detailed warnings on upcoming space weather events. These events, like the solar flares and coronal mass ejections, or CMEs, can wreak havoc with orbiting satellites, radio communications and even the world’s power grids.
One reason why it’s so hard to study magnetic reconnection is that it can’t be witnessed directly because magnetic fields are invisible. Instead, scientists have been using a combination of computer modeling and a scant sampling of observations around magnetic reconnection events to try to understand what’s going on.
“The community is still trying to understand how magnetic reconnection causes flares,” said Yang Su, a solar scientist at the University of Graz in Austria. “We have so many pieces of evidence, but the picture is not yet complete.”
Su found some new visual proof of this phenomenon as he was pouring through observations that had been made by the SDO spacecraft. It was something that would have been very difficult to find by using SDO data alone; the scientist actually found some direct images of magnetic reconnection itself taking place on the sun.
What the scientist saw was were two bundles of the magnetic field lines shift near each other, which then meet briefly to form what seemed to be an “X,” and then blast apart from each other with one group of lines leaping into space and while another set fell back down into the sun.
Now, since the magnetic fields themselves are invisible, they can be seen by space telescopes as bright lines that loop and arc throughout the sun’s atmosphere. These visible bright line lines are actually the magnetic fields lined with plasma — material made up of force charged particles that make up much of the sun — that pulse up and along the length of the fields.
“It can often be hard to tell what’s truly happening in three dimensions from these images, since the pictures themselves are two-dimensional,” said Gordon Holman, a solar scientist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “But if you look long enough and compare data from other instruments, you can make a good case for what’s going on.”
To get conformation of what the scientists were actually seeing, they went to a second spacecraft that’s keeping an eye on the sun, the Reuven Ramaty High Energy Solar Spectroscopic Imager, or RHESSI. This spacecraft gathers data to form spectrograms that can show researchers where extremely hot material may be present during various solar events.
In confirming the images scientists gathered from the SDO, the spectrograms produced by the RHESSI showed that there were hot pockets of solar material forming both above and beneath magnetic reconnection points, which provided the scientists with an established signature of the reconnection event.
Combining the images and data from both the SDO and RHESSI, scientists were then able to describe what they were actually seeing. Putting together the studies with information from both spacecraft allowed the scientists to confirm many previous models and theories. And at the same time, they were able to provide some new, three-dimensional aspects of the magnetic reconnection process.
The research and findings were outlined in the July 14th edition of the journal Nature Physics.
NASA video explains what the SDO and RHESSI spacecraft captured
The Hubble Space Telescope has helped scientists determine the color of a planet outside of our Solar System for the first time.
Located about 63 light years from Earth, the planet known as HD 189733b would be a deep cobalt blue if viewed at close range, similar to Earth’s color as seen from space.
Despite the comparable colors, that’s where the similarities between Earth and the exoplanet end, researchers say. Astronomers describe the planet, referred to as a “deep blue dot,” as a huge gas giant orbiting close to its host star, HD 189733, which is located in the constellation of Vulpecula, the Fox.
The planet’s atmosphere has a blazing temperature of over 1,000 degrees Celsius, and when it rains there, it rains hot molten glass that falls sideways due to violent 7,000 kilometer-per-hour winds.
HD 189733b is one of the closest extra-solar planets to Earth that can be observed to cross the face of its star. Its atmosphere, researcher say, is unsettled and unusual in nature, “with hazes and violent flares.”
“This planet has been studied well in the past, both by ourselves and other teams,” said Frederic Pont from the University of Exeter. “But measuring its color is a real first; we can actually imagine what this planet would look like if we were able to look at it directly.”
The research team was able to determine the exoplanet’s color by measuring how much light reflected off its surface, a property known as albedo, or a reflection coefficient.
Astronomers say HD 189733b is faint compared to surrounding objects. Since the planet is so close to its bright star, the researchers had to isolate its light from the starlight. To do this, the team used Hubble’s Space Telescope Imaging Spectrograph (STIS) to study the planet/star system before, during, and after the exoplanet went behind its star during orbit.
“We saw the brightness of the whole system drop in the blue part of the spectrum when the planet passed behind its star,” said the study’s first author, Tom Evans from the University of Oxford. “From this, we can gather that the planet is blue, because the signal remained constant at the other colors we measured.”
Unlike the Earth, HD 189733b’s cobalt blue color does not come from the reflection of oceans, but rather from its hazy and stormy atmosphere which scientists think may be mixed with silicate particles that disperse blue light.
“It’s difficult to know exactly what causes the color of a planet’s atmosphere, even for planets in the Solar System,” said Pont. “But these new observations add another piece to the puzzle over the nature and atmosphere of HD 189733b. We are slowly painting a more complete picture of this exotic planet.”
NASA said the journey began last week from an area called Glenelg, which is about 400 meters east-southeast of Curiosity’s landing site. According to mission officials, the rover drove about 18 meters toward Mount Sharp on July 4, and another 40 meters on July 7, traveling a total of about 58 meters toward its destination, with 7,942 meters to go.
Curiosity can travel an average of 30 meters per hour – depending on variables such as power levels, slippage, steep terrain and visibility – but the rover will take its time getting to Mount Sharp, stopping, or possibly backtracking, should it spot something of interest. Challenging terrain could also slow the rover’s progress.
The mission team is anxious for Curiosity to explore the lower layers of Mount Sharp, where they expect to find evidence of how the ancient Martian environment changed and evolved.
Each of the layers offers an opportunity to look back into Mars’ geological history, said Rob Manning, the Mars Science Laboratory’s (MSL) chief engineer. Curiosity’s mission to Mars is scheduled to last one Martian year, about 687 Earth days. But, if the rover continues to operate, NASA could extend its mission, allowing Curiosity to continue its journey up Mount Sharp.
“We will continue going up and explore and explore,” Manning said.
Since beginning its mission after last August’s landing, Curiosity has made a number of discoveries, including finding evidence of an ancient wet environment with conditions favorable for microbial life.
That’s more than twice as many potentially habitable planets than was previously thought.
The new report from two Chicago area universities finds that clouds surrounding these planets may be hiding them from detection.
The researchers drew upon current data from NASA’s Kepler Mission, which searched for Earth-like planets orbiting other stars up until this past May. The new study from Northwestern University and the University of Chicago suggests there is approximately one Earth-size planet in the habitable zone of each red dwarf.
“Most of the planets in the Milky Way orbit red dwarfs,” said Nicolas Cowan, a postdoctoral fellow at Northwestern University. “A thermostat that makes such planets more clement means we don’t have to look as far to find a habitable planet.”
The findings contradict other recent studies, including one from the Harvard-Smithsonian Center for Astrophysics, which found our galaxy has about 4.5 billion Earth-sized planets. Another study from the California Institute of Technology (Caltech) estimated there are about 30 billion of these planets in our galaxy.
“Those numbers are confusing, partially because they are still being sorted out,” Cowan said in an email to Science World.
All three studies were based on virtually the same data from Kepler.
“Our 3D calculations of the HZ [Habitable Zone] move its inner edge much closer to the star,” said Cowan. “The Kepler planetary demographics tell us how many planets orbit at what distance from their host star. We therefore know that our revision to the HZ accommodates roughly twice as many planets.”
For decades, scientists have said that a star’s habitable zone is an area where planets can orbit their star while still being able to retain liquid water at their surfaces. But the researchers say that formula doesn’t take clouds, which have a major climatic influence, into consideration.
“Clouds cause warming, and they cause cooling on Earth,” said Dorian Abbot, an assistant professor in geophysical sciences the University of Chicago and member of the research team. “They reflect sunlight to cool things off, and they absorb infrared radiation from the surface to make a greenhouse effect. That’s part of what keeps the planet warm enough to sustain life.”
According to the team’s research, in order for a planet to be maintain liquid water it would need to complete an orbit around its star about once a year, just as Earth orbits the sun.
But, “if you’re orbiting around a low mass or dwarf star, you have to orbit about once a month, once every two months to receive the same amount of sunlight that we receive from the sun,” Cowan said.
Since these planets would maintain such tight orbits, they would sooner or later become “tidally locked with their sun,” with the same side of the planet are always facing their suns, similar to how the moon orbits around Earth. According to computations made by the Chicago area team, the sun would always be directly above the planet, “at high noon.”
If astronomers find that tidally locked planets have no substantial cloud cover, they will measure the highest temperatures of the planet when its dayside faces their telescopes. When that planet continues its orbit around its star and shows its dark side to the telescope, temperatures would reach their lowest point.
But if the exoplanet has highly reflective clouds dominating its dayside, they would block much of the infrared radiation from its surface.
“You would measure the coldest temperatures when the planet is on the opposite side, and you would measure the warmest temperatures when you are looking at the night side, because there you are actually looking at the surface rather than these high clouds,” said Jun Yang, a member of the research team from the University of Chicago.
Previous efforts to simulate an exoplanet habitable zone’s inner edge were used one-dimensional calculations and mostly ignored clouds, said the Chicago researchers. Their work instead focused on charting how temperature decreases with altitude.
For the first time, by using three-dimensional global calculations, the research team was able to find the effect of water clouds on the inner edge of the habitable zone. The team used simulations similar to those used to predict Earth’s climate.
“There’s no way you can do clouds properly in one-dimension,” Cowan said. “But in a three-dimensional model, you’re actually simulating the way air moves and the way moisture moves through the entire atmosphere of the planet.”
The research team anticipates the forthcoming James Webb Space Telescope will verify its findings. If the new telescope, which NASA hopes will launch in 2018, detects a signal from an exoplanet, “it’s almost definitely from clouds, and it’s a confirmation that you do have surface liquid water,” said Abbot.
Did you know that the Sun’s outer atmosphere, or corona, is much hotter than its surface? Scientists have been quite curious about a mysterious interface region of the Sun’s atmosphere that amplifies energy from about 5,800 degrees Kelvin on the surface, or photosphere, to around 1,000,000 degrees Kelvin in the corona.
With Thursday’s launch of its Interface Region Imaging Spectrograph or IRIS spacecraft, NASA is planning to find out just how solar matter moves, gathers energy and heats up as it passes through the Sun’s chromosphere, it’s solar transition region, and into the corona that powers the solar wind.
According to NASA, most of the sun’s ultraviolet radiation, which they say has an impact on Earth’s climate, is also produced in this interface region.
“We are thrilled to add IRIS to the suite of NASA missions studying the sun,” said John Grunsfeld, NASA’s associate administrator for science in Washington. “IRIS will help scientists understand the mysterious and energetic interface between the surface and corona of the sun.”
At 6:30PM Thursday, an Orbital L-1011 carrier aircraft, with the Pegasus XL rocket and its IRIS spacecraft payload strapped beneath, it took off from California’s Vandenberg Air Force base to a release site over the Pacific Ocean.
Five seconds after being dropped by the plane, the first stage of the Pegasus XL ignited and carried IRIS into space. NASA officials said that the IRIS spacecraft successfully separated from its launch rocket’s third stage at 7:40 PM PDT. Twenty-five minutes later, at 8:05 PM PDT, the IRIS team received confirmation that the spacecraft successfully deployed its solar arrays (seen in the top photo), had power, acquired its target, the sun, and that all systems were operating as expected.
NASA Video of the release and launch of the Pegasus XL from its Orbital L-1011 carrier aircraft
NASA says the IRIS is now going through what it calls a 60-day commissioning phase to make sure the spacecraft and its onboard instruments are functioning properly.
Mission leaders say that they are centering IRIS’ science investigation on three main themes.
1. Which types of non-thermal energy dominate in the Sun’s chromosphere and beyond?
2. How does the chromosphere regulate mass and energy supply the corona and heliosphere, which NASA says is the giant magnetic bubble that extends way beyond the orbit of Pluto and contains our solar system, the solar wind, and the entire solar magnetic field?
According to NASA, the IRIS spacecraft, which weighs 167 Kilograms, is 2.1 meters long and 3.7 meters across, was designed by the Smithsonian Astrophysical Observatory headquartered at the Harvard-Smithsonian Center for Astrophysics in Cambridge, Massachusetts.
After its launch, IRIS was placed in a sun-synchronous polar orbit where it will circle over the north and south poles and pass over the same part of Earth at about the same time of day. This unique orbit will allow the IRIS mission team to make almost continuous solar observations during its planned two-year mission.
Scientists conducted high-tech tests on the tooth enamel found in remains of ancient hominid species. The results indicated that, prior to that dietary change, the hominids ate pretty much like chimpanzees, dining on items like fruits and some leaves.
But then some hominid species started adding grasses and flowering plants to their daily menus.
“We don’t know exactly what happened,” said Sponheimer. “But we do know that after about 3.5 million years ago, some of these hominids started to eat things that they did not eat before, and it is quite possible that these changes in diet were an important step in becoming human.”
Scientists had previously analyzed the teeth of about 87 ancient hominid specimens. Sponheimer and his team came up with new detailed information on the teeth of 88 additional specimens, which also included five previously unanalyzed hominid species.
To find out what kind of plants these early hominids ate, Sponheimer’s team analyzed the carbon isotopes found on the fossilized teeth. The researchers found the carbon signals of two distinct plant groups; the first, called C3, came from plants like trees and bushes, while the other, called C4, came from plants like grasses and sedges, which are flowering grasses.
The researchers also examined the microscopic wear of hominid teeth, which provided scientists with more information on the foods they were eating. Since there were multiple species of hominids, there was no such thing as one specific hominid diet.
While early ancestors in the genus Homo, which includes modern humans and the 3 million-year-old fossil known as Lucy – who many scientists see as the matriarch of today’s humans – were diversifying their diets with different food choices, another type of short, upright hominid, the Paranthropus boisei, who also lived in Eastern Africa at the time, was moving toward a much more specific diet made up mostly of items like the grasses.
Scientists had given the P. boisei hominids the nickname “Nutcracker Man” because it had large, flat teeth and powerful jaws that may have been powerful enough to crack nuts. But, according to Sponheimer, more recent analyses suggest they might have actually used their back teeth to grind grasses and sedges.
“We now have the first direct evidence that, as the cheek teeth on hominids got bigger, their consumption of plants like grasses and sedges increased,” he said. “We also see niche differentiation between Homo and Paranthropus. It looks probable that Paranthropus boisei had a relatively restricted diet, while members of the genus Homo were eating a wider variety of things. The genus Paranthropus went extinct about one million years ago, while the genus Homo, that includes us, obviously did not.”
Researchers are puzzled at the differences in the evolution of those hominids living in eastern Africa compared to those from southern Africa.
Another hominid, called Paranthropus robustus, which was found in southern Africa was very anatomically similar its eastern African cousin, P. boisei. But Sponheimer and his team found that the teeth of the two had quite different carbon isotopic compositions in their teeth, which suggested that they each ate different diets.
The southern African P. robustus hominid appeared to have augmented its diet of grasses and sedges with items from the C3 group such as trees and bushes.
“This has probably been one of the biggest surprises to us so far,” said Sponheimer. “We had generally assumed that the Paranthropus species were just variants on the same ecological theme, and that their diets would probably not differ more than those of two closely related monkeys in the same forest.
But the researchers found that their isotopic evidence of each of the hominids indicated that their diets were so different from each other that they could have been as different as primate diets can be.
“Ancient fossils don’t always reveal what we think they will. The upside of this disconnect is that it can teach us a great deal, including the need for caution in making pronouncements about the diets of long-dead critters,” said Sponheimer.