Month: March 2018

Suomi NPP Satellite Sees Tropical Cyclone Hola Over Vanuatu

On Mar. 8 at 0230 UTC (Mar. 7 at 9:30 p.m. EST) the Visible Infrared Imaging Radiometer Suite (VIIRS) instrument aboard NASA-NOAA’s Suomi NPP satellite showed the center of Hola was located southwest of the Pacific island nation of Vanuatu. The VIIRS image showed a well-rounded circulation center with bands of powerful thunderstorms wrapping into the center. The VIIRS image showed the northern and eastern quadrants of the storm extended over Vanuatu.

On March 8, warnings were in effect in Vanuatu and a pre-alert was posted for New Caledonia. In Vanuatu a tropical cyclone warning is in force for Shefa province. In New Caledonia the territory is on pre-alert, with the exception of Ouvéa, Maré and Lifou, which are on tropical cyclone alert 1. The pre-alert is expected to be upgraded to alert 2 within a day.

At 4 a.m. EST (0900 UTC) on March 8, Hola’s maximum sustained winds were near 109 mph (95 knots/175 kph). It was centered near 17.6 degrees south latitude and 165.4 degrees east longitude. That’s about 166 nautical miles west of Port Vila, Vanuatu. Hola was moving to the south-southwest at 4.6 mph (4 knots/7.4 kph).

The Joint Typhoon Warning Center forecast calls for Hola to move to the south-southeast over the next few days. The storm will intensify to 115 knots east of New Caledonia. Hola is then expected to weaken and become extra-tropical on approach to the North Island of New Zealand.

A Peculiar Galactic Clash

Galaxies are not static islands of stars — they are dynamic and ever-changing, constantly on the move through the darkness of the Universe. Sometimes, as seen in this spectacular Hubble image of Arp 256, galaxies can collide in a crash of cosmic proportions.

350 million light-years away in the constellation of Cetus (the Sea Monster), a pair of barred spiral galaxies have just begun a magnificent merger. This image suspends them in a single moment, freezing the chaotic spray of gas, dust and stars kicked up by the gravitational forces pulling the two galaxies together.

Though their nuclei are still separated by a large distance, the shapes of the galaxies in Arp 256 are impressively distorted. The galaxy in the upper part of the image contains very pronounced tidal tails — long, extended ribbons of gas, dust and stars.

The galaxies are ablaze with dazzling regions of star formation: the bright blue fireworks are stellar nurseries, churning out hot infant stars. These vigorous bursts of new life are triggered by the massive gravitational interactions, which stir up interstellar gas and dust out of which stars are born.

Arp 256 was first catalogued by Halton Arp in 1966, as one of 338 galaxies presented in the aptly-named Atlas of Peculiar Galaxies. The goal of the catalogue was to image examples of the weird and wonderful structures found among nearby galaxies, to provide snapshots of different stages of galactic evolution. These peculiar galaxies are like a natural experiment played out on a cosmic scale and by cataloguing them, astronomers can better understand the physical processes that warp spiral and elliptical galaxies into new shapes.

Many galaxies in this catalogue are dwarf galaxies with indistinct structures, or active galaxies generating powerful jets — but a large number of the galaxies are interacting, such as Messier 51, the Antennae Galaxies, and Arp 256. Such interactions often form streamer-like tidal tails as seen in Arp 256, as well as bridges of gas, dust and stars between the galaxies.

Long ago, when our expanding Universe was much smaller, interactions and mergers were more common; in fact, they are thought to drive galactic evolution to this day. The galaxies in the Arp 256 system will continue their gravitational dance over the next millions of years, at first flirtatious, and then intimate, before finally morphing into a single galaxy.

This spectacular image was taken by Hubble’s Advanced Camera for Surveys (ACS) and the Wide Field Camera 3 (WFC3). It is a new version of an image already released in 2008 that was part a large collection of 59 images of merging galaxies taken for Hubble’s 18th anniversary.

NASA Juno Finds Jupiter’s Jet-Streams Are Unearthly

Data collected by NASA’s Juno mission to Jupiter indicate that the atmospheric winds of the gas-giant planet run deep into its atmosphere and last longer than similar atmospheric processes found here on Earth. The findings will improve understanding of Jupiter’s interior structure, core mass and, eventually, its origin.

Other Juno science results released today include that the massive cyclones that surround Jupiter’s north and south poles are enduring atmospheric features and unlike anything else encountered in our solar system. The findings are part of a four-article collection on Juno science results being published in the March 8 edition of the journal Nature.

“These astonishing science results are yet another example of Jupiter’s curve balls, and a testimony to the value of exploring the unknown from a new perspective with next-generation instruments.Juno’s unique orbit and evolutionary high-precision radio science and infrared technologies enabled these paradigm-shifting discoveries,” said Scott Bolton, principal investigator of Juno from the Southwest Research Institute, San Antonio. “Juno is only about one third the way through its primary mission, and already we are seeing the beginnings of a new Jupiter.”

The depth to which the roots of Jupiter’s famous zones and belts extend has been a mystery for decades. Gravity measurements collected by Juno during its close flybys of the planet have now provided an answer.

“Juno’s measurement of Jupiter’s gravity field indicates a north-south asymmetry, similar to the asymmetry observed in its zones and belts,” said Luciano Iess, Juno co-investigator from Sapienza University of Rome, and lead author on a Nature paper on Jupiter’s gravity field.

On a gas planet, such an asymmetry can only come from flows deep within the planet; and on Jupiter, the visible eastward and westward jet streams are likewise asymmetric north and south. The deeper the jets, the more mass they contain, leading to a stronger signal expressed in the gravity field. Thus, the magnitude of the asymmetry in gravity determines how deep the jet streams extend.

“Galileo viewed the stripes on Jupiter more than 400 years ago,” said Yohai Kaspi, Juno co-investigator from the Weizmann Institute of Science, Rehovot, Israel,and lead author of a Nature paper on Jupiter’s deep weather layer. “Until now, we only had a superficial understanding of them and have been able to relate these stripes to cloud features along Jupiter’s jets. Now, following the Juno gravity measurements, we know how deep the jets extend and what their structure is beneath the visible clouds. It’s like going from a 2-D picture to a 3-D version in high definition.”

The result was a surprise for the Juno science team because it indicated that the weather layer of Jupiter was more massive, extending much deeper than previously expected. The Jovian weather layer, from its very top to a depth of 1,900 miles (3,000 kilometers), contains about one percent of Jupiter’s mass (about 3 Earth masses).

“By contrast, Earth’s atmosphere is less than one millionth of the total mass of Earth,” said Kaspi “The fact that Jupiter has such a massive region rotating in separate east-west bands is definitely a surprise.”

The finding is important for understanding the nature and possible mechanisms driving these strong jet streams. In addition, the gravity signature of the jets is entangled with the gravity signal of Jupiter’s core.

Another Juno result released today suggests that beneath the weather layer, the planet rotates nearly as a rigid body.”This is really an amazing result, and future measurements by Juno will help us understand how the transition works between the weather layer and the rigid body below,” said Tristan Guillot, a Juno co-investigator from the Université Côte d’Azur, Nice, France, and lead author of the paper on Jupiter’s deep interior. “Juno’s discovery has implications for other worlds in our solar system and beyond. Our results imply that the outer differentially-rotating region should be at least three times deeper in Saturn and shallower in massive giant planets and brown dwarf stars.”

A truly striking result released in the Nature papers is the beautiful new imagery of Jupiter’s poles captured by Juno’s Jovian Infrared Auroral Mapper (JIRAM) instrument. Imaging in the infrared part of the spectrum, JIRAM captures images of light emerging from deep inside Jupiter equally well, night or day. JIRAM probes the weather layer down to 30 to 45 miles (50 to 70 kilometers) below Jupiter’s cloud tops.

“Prior to Juno we did not know what the weather was like near Jupiter’s poles. Now, we have been able to observe the polar weather up-close every two months,” said Alberto Adriani, Juno co-investigator from the Institute for Space Astrophysics and Planetology, Rome, and lead author of the paper. “Each one of the northern cyclones is almost as wide as the distance between Naples, Italy and New York City — and the southern ones are even larger than that. They have very violent winds, reaching, in some cases, speeds as great as 220 mph (350 kph). Finally, and perhaps most remarkably, they are very close together and enduring. There is nothing else like it that we know of in the solar system.”

Jupiter’s poles are a stark contrast to the more familiar orange and white belts and zones encircling the planet at lower latitudes. Its north pole is dominated by a central cyclone surrounded by eight circumpolar cyclones with diameters ranging from 2,500 to 2,900 miles (4,000 to 4,600 kilometers) across. Jupiter’s south pole also contains a central cyclone, but it is surrounded by five cyclones with diameters ranging from 3,500 to 4,300 miles (5,600 to 7,000 kilometers) in diameter. Almost all the polar cyclones, at both poles, are so densely packed that their spiral arms come in contact with adjacent cyclones. However, as tightly spaced as the cyclones are, they have remained distinct, with individual morphologies over the seven months of observations detailed in the paper.

“The question is, why do they not merge?” said Adriani. “We know with Cassini data that Saturn has a single cyclonic vortex at each pole. We are beginning to realize that not all gas giants are created equal.”

To date, Juno has completed 10 science passes over Jupiter and logged almost 122 million miles (200 million kilometers), since entering Jupiter’s orbit on July 4, 2016. Juno’s 11th science pass will be on April 1.

Juno launched on Aug. 5, 2011, from Cape Canaveral, Florida. During its mission of exploration, Juno soars low over the planet’s cloud tops — as close as about 2,200 miles (3,500 kilometers). During these flybys, Juno is probing beneath the obscuring cloud cover of Jupiter and studying its auroras to learn more about the planet’s origins, structure, weather layer and magnetosphere.

Scientists Crack 70-Year-Old Mystery Of How Magnetic Waves Heat The Sun

Scientists at Queen’s University Belfast have led an international team to the ground-breaking discovery that magnetic waves crashing through the sun may be key to heating its atmosphere and propelling the solar wind.

The sun is the source of energy that sustains all life on Earth but much remains unknown about it. However, a group of researchers at Queen’s have now unlocked some mysteries in a research paper, which has been published in Nature Physics.

In 1942, Swedish physicist and engineer Hannes Alfvén predicted the existence of a new type of wave due to magnetism acting on a plasma, which led him to obtain the Nobel Prize for Physics in 1970. Since his prediction, Alfvén waves have been associated with a variety of sources, including nuclear reactors, the gas cloud that envelops comets, laboratory experiments, medical MRI imaging and in the atmosphere of our nearest star – the sun.

Scientists have suggested for many years that these waves may play an important role in maintaining the sun’s extremely high temperatures but until now had not been able to prove it.

Dr. David Jess from the School of Mathematics and Physics at Queen’s University Belfast explains: “For a long time scientists across the globe have predicted that Alfvén waves travel upwards from the solar surface to break in the higher layers, releasing enormous amounts of energy in the form of heat. Over the last decade scientists have been able to prove that the waves exist but until now there was no direct evidence that they had the capability to convert their movement into heat.

“At Queen’s, we have now led a team to detect and pinpoint the heat produced by Alfvén waves in a sunspot. This theory was predicted some 75 years ago but we now have the proof for the very first time. Our research opens up a new window to understanding how this phenomenon could potentially work in other areas such as energy reactors and medical devices.”

The study used advanced high-resolution observations from the Dunn Solar Telescope in New Mexico (USA) alongside complementary observations from NASA’s Solar Dynamics Observatory, to analyse the strongest magnetic fields that appear in sunspots. These sunspots have intense fields similar to modern MRI machines in hospitals and are much bigger than our own planet.

Dr. Samuel Grant from Queen’s comments: “By breaking the sun’s light up into its constituent colours, our international team of researchers were able to examine the behaviour of certain elements from the periodic table within the sun’s atmosphere, including calcium and iron.

“Once these elements had been extracted, intense flashes of light were detected in the image sequences. These intense flashes had all the hallmarks of the Alfvén waves converting their energy into shock waves, in a similar way to a supersonic aircraft creating a boom as it exceeds the speed of sound. The shock waves then ripple through the surrounding plasma, producing extreme heat. Using supercomputers, we were able to analyse the data and show for the first time in history that the Alfvén waves were capable of increasing plasma temperatures violently above their calm background.”

Hubble Finds Huge System Of Dusty Material Enveloping The Young Star HR 4796A

Astronomers have used NASA’s Hubble Space Telescope to uncover a vast, complex dust structure, about 150 billion miles across, enveloping the young star HR 4796A. A bright, narrow, inner ring of dust is already known to encircle the star and may have been corralled by the gravitational pull of an unseen giant planet. This newly discovered huge structure around the system may have implications for what this yet-unseen planetary system looks like around the 8-million-year-old star, which is in its formative years of planet construction.

The debris field of very fine dust was likely created from collisions among developing infant planets near the star, evidenced by a bright ring of dusty debris seen 7 billion miles from the star. The pressure of starlight from the star, which is 23 times more luminous than the Sun, then expelled the dust far into space.

But the dynamics don’t stop there. The puffy outer dust structure is like a donut-shaped inner tube that got hit by a truck. It is much more extended in one direction than in the other and so looks squashed on one side even after accounting for its inclined projection on the sky. This may be due to the motion of the host star plowing through the interstellar medium, like the bow wave from a boat crossing a lake. Or it may be influenced by a tidal tug from the star’s red dwarf binary companion (HR 4796B), located at least 54 billion miles from the primary star.

“The dust distribution is a telltale sign of how dynamically interactive the inner system containing the ring is,” said Glenn Schneider of the University of Arizona, Tucson, who used Hubble’s Space Telescope Imaging Spectrograph (STIS) to probe and map the small dust particles in the outer reaches of the HR 4796A system, a survey that only Hubble’s sensitivity can accomplish.

“We cannot treat exoplanetary debris systems as simply being in isolation. Environmental effects, such as interactions with the interstellar medium and forces due to stellar companions, may have long-term implications for the evolution of such systems. The gross asymmetries of the outer dust field are telling us there are a lot of forces in play (beyond just host-star radiation pressure) that are moving the material around. We’ve seen effects like this in a few other systems, but here’s a case where we see a bunch of things going on at once,” Schneider further explained.

Though long hypothesized, the first evidence for a debris disk around any star was uncovered in 1983 with NASA’s Infrared Astronomical Satellite. Later photographs revealed an edge-on debris disk around the southern star Beta Pictoris. In the late 1990s, Hubble’s second-generation instruments, which had the capability of blocking out the glare of a central star, allowed many more disks to be photographed. Now, such debris rings are thought to be common around stars. About 40 such systems have been imaged to date, largely by Hubble.

Japanese Volcano Spews Ash, Lava In Strongest Eruption In Years

TOKYO -A volcano in southern Japan that appeared in a James Bond film had its biggest eruption in years Tuesday, shooting smoke and ash thousands of feet into the sky and grounding dozens of flights at a nearby airport, officials said. The Meteorological Agency said the Shinmoedake volcano on Japan’s southernmost main island of Kyushu erupted violently several times, and some lava was rising inside a crater.

“The mountain has been erupting for a while, but this is the strongest day yet,” an official at the Japanese Meteorological Agency told Reuters. “This will go on for a while.”

Public broadcaster NHK showed gray volcanic smoke billowing into the sky and orange lava rising to the mouth of the crater. The Meteorological Agency said ash and smoke shot up about 7,500 feet into the sky in the volcano’s biggest explosion since 2011.

In Kirishima city at the foot of the volcano, pedestrians wore surgical masks or covered their noses with hand towels, while others used umbrellas to protect from falling ash. Cars had layers of ash on their roofs.

There were no reports of injuries or damage from the eruptions. The agency said the volcanic activity is expected to continue and cautioned residents against the possibility of flying rocks and pyroclastic flows — superheated gas and volcanic debris that race down the slopes at high speeds, incinerating or vaporizing everything in their path.

The volcano, seen in the 1967 James Bond film “You Only Live Twice,” has had smaller eruptions since last week.

Entry to the 4,660-foot-high volcano was restricted. About 80 flights in and out of nearby Kagoshima airport were canceled.

Japan, which sits on the Pacific “Ring of Fire,” has 110 active volcanoes and is prone to earthquakes and volcanic eruptions.

An eruption of Mount Ontake in 2014 killed about 60 people. In January, a surprise eruption of another volcano in central Japan killed a soldier during ski training and injured 11 others. Several other Japanese volcanoes have had smaller eruptions.

Chemical Sleuthing Unravels Possible Path To Forming Life’s Building Blocks In Space

Scientists have used lab experiments to retrace the chemical steps leading to the creation of complex hydrocarbons in space, showing pathways to forming 2-D carbon-based nanostructures in a mix of heated gases.

The latest study, which featured experiments at the Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab), could help explain the presence of pyrene, which is a chemical compound known as a polycyclic aromatic hydrocarbon, and similar compounds in some meteorites.

A team of scientists, including researchers from Berkeley Lab and UC Berkeley, participated in the study, published March 5 in the Nature Astronomy journal. The study was led by scientists at the University of Hawaii at Manoa and also involved theoretical chemists at Florida International University.

“This is how we believe some of the first carbon-based structures evolved in the universe,” said Musahid Ahmed, a scientist in Berkeley Lab’s Chemical Sciences Division who joined other team members to perform experiments at Berkeley Lab’s Advanced Light Source (ALS).

“Starting off from simple gases, you can generate one-dimensional and two-dimensional structures, and pyrene could lead you to 2-D graphene,” Ahmed said. “From there you can get to graphite, and the evolution of more complex chemistry begins.”

Pyrene has a molecular structure composed of 16 carbon atoms and 10 hydrogen atoms. Researchers found that the same heated chemical processes that give rise to the formation of pyrene are also relevant to combustion processes in vehicle engines, for example, and the formation of soot particles.

The latest study builds on earlier work that analyzed hydrocarbons with smaller molecular rings that have also been observed in space, including in Saturn’s moon Titan — namely benzene and naphthalene.

Ralf I. Kaiser, one of the study’s lead authors and a chemistry professor at the University of Hawaii at Manoa, said, “When these hydrocarbons were first seen in space, people got very excited. There was the question of how they formed.” Were they purely formed through reactions in a mix of gases, or did they form on a watery surface, for example?

Ahmed said there is an interplay between astronomers and chemists in this detective work that seeks to retell the story of how life’s chemical precursors formed in the universe.

“We talk to astronomers a lot because we want their help in figuring out what’s out there,” Ahmed said, “and it informs us to think about how it got there.”

Kaiser noted that physical chemists, on the other hand, can help shine a light on reaction mechanisms that can lead to the synthesis of specific molecules in space.

Pyrene belongs to a family known as polycyclic aromatic hydrocarbons, or PAHs, that are estimated to account for about 20 percent of all carbon in our galaxy. PAHs are organic molecules that are composed of a sequence of fused molecular rings. To explore how these rings develop in space, scientists work to synthesize these molecules and other surrounding molecules known to exist in space.

Alexander M. Mebel, a chemistry professor at Florida International University who participated in the study, said, “You build them up one ring at a time, and we’ve been making these rings bigger and bigger. This is a very reductionist way of looking at the origins of life: one building block at a time.”

For this study, researchers explored the chemical reactions stemming from a combination of a complex hydrocarbon known as the 4-phenanthrenyl radical, which has a molecular structure that includes a sequence of three rings and contains a total of 14 carbon atoms and nine hydrogen atoms, with acetylene (two carbon atoms and two hydrogen atoms).

Acetylene is an extremely volatile gas that has a high risk of a dangerous chemical reaction called decomposition. Decomposition can cause high energy explosions and therefore to stabilize the gas against decomposition, acetylene is never stored in a pure state.

Instead, it is mixed with a liquid solvent (usually acetone) and stored in a cylinder containing a porous filler material (also known as a porous mass). You can learn more about storing acetylene by heading to the Storemasta website.

Chemical compounds and infrastructure needed for the study were not commercially available, said Felix Fischer, an assistant professor of chemistry at UC Berkeley who also contributed to the study, so his lab prepared the samples. “These chemicals are very tedious to synthesize in the laboratory,” he said. However, laboratory manufacturers like ISG Fume and similar reputed manufactures do provide custom build fume cabinets and other safety equipment (Find out more at ISG Fume). These cabinets could prove useful in such studies.

At the ALS, researchers injected the gas mixture into a microreactor that heated the sample to a high temperature to simulate the proximity of a star. The ALS generates beams of light, from infrared to X-ray wavelengths, to support a range of science experiments by visiting and in-house researchers.

The mixture of gases was jetted out of the microreactor through a tiny nozzle at supersonic speeds, arresting the active chemistry within the heated cell. The research team then focused a beam of vacuum ultraviolet light from the synchrotron on the heated gas mixture that knocked away electrons (an effect known as ionization).

They then analyzed the chemistry taking place using a charged-particle detector that measured the varied arrival times of particles that formed after ionization. These arrival times carried the telltale signatures of the parent molecules. These experimental measurements, coupled with Mebel’s theoretical calculations, helped researchers to see the intermediate steps of the chemistry at play and to confirm the production of pyrene in the reactions.

Mebel’s work showed how pyrene (a four-ringed molecular structure) could develop from a compound known as phenanthrene (a three-ringed structure). These theoretical calculations can be useful for studying a variety of phenomena, “from combustion flames on Earth to outflows of carbon stars and the interstellar medium,” Mebel said.

Kaiser added, “Future studies could study how to create even larger chains of ringed molecules using the same technique, and to explore how to form graphene from pyrene chemistry.”

Other experiments conducted by team members at the University of Hawaii will explore what happens when researchers mix hydrocarbon gases in icy conditions and simulate cosmic radiation to see whether that may spark the creation of life-bearing molecules.

“Is this enough of a trigger?” Ahmed said. “There has to be some self-organization and self-assembly involved” to create life forms. “The big question is whether this is something that, inherently, the laws of physics do allow.”