Researchers Find Evidence For A New Fundamental Constant Of The Sun

New research undertaken at Northumbria University, Newcastle shows that the sun’s magnetic waves behave differently than currently believed.

Their findings have been reported in Nature Astronomy.

After examining data gathered over a 10-year period, the team from Northumbria’s Department of Mathematics, Physics and Electrical Engineering found that magnetic waves in the sun’s corona – its outermost layer of atmosphere – react to sound waves escaping from the inside of the sun.

These magnetic waves, known as Alfvénic waves, play a crucial role in transporting energy around the sun and the solar system. The waves were previously thought to originate at the sun’s surface, where boiling hydrogen reaches temperatures of 6,000 degrees and churns the sun’s magnetic field.

However, the researchers have found evidence that the magnetic waves also react – or are excited – higher in the atmosphere by sound waves leaking out from the inside of the sun.

The team discovered that the sound waves leave a distinctive marker on the magnetic waves. The presence of this marker means that the sun’s entire corona is shaking in a collective manner in response to the sound waves. This is causing it to vibrate over a very clear range of frequencies.

This newly-discovered marker is found throughout the corona and was consistently present over the 10-year time-span examined. This suggests that it is a fundamental constant of the sun – and could potentially be a fundamental constant of other stars.

The findings could therefore have significant implications for our current ideas about how magnetic energy is transferred and used in stellar atmospheres.

Dr. Richard Morton, the lead author of the report and a senior lecturer at Northumbria University, said: “The discovery of such a distinctive marker – potentially a new constant of the sun – is very exciting. We have previously always thought that the magnetic waves were excited by the hydrogen at the surface, but now we have shown that they are excited by these sound waves. This could lead to a new way to examine and classify the behaviour of all stars under this unique signature. Now we know the signature is there, we can go looking for it on other stars.

“The sun’s corona is over one hundred times hotter than its surface and energy stemming from the Alfvénic waves is believed to be responsible for heating the corona to a temperature of around one million degrees. The Alfvénic waves are also responsible for heating and accelerating powerful solar wind from the sun which travels through the solar system. These winds travel at speeds of around a million miles per hour. They also affect the atmosphere of stars and planets, impacting on their own magnetic fields, and cause phenomena such as aurora.”

Dr. Morton added: “Our evidence shows that the sun’s internal acoustic oscillations play a significant role in exciting the magnetic Alfvénic waves. This can give the waves different properties and suggests that they are more susceptible to an instability, which could lead to hotter and faster solar winds.”

Dr. Morton and Professor McLaughlin are currently working with NASA to analyse images of the sun which were taken by NASA’s High-Resolution Coronal Imager, Hi-C.

A Thousand New Objects And Phenomena In Night Sky

Casual stargazers may look at the black area among stars and think that there’s nothing there except empty space. But the night sky hides many secrets invisible to the naked eye.

Less than a year into its mission, a sky-survey camera in Southern California shows just how full the sky is. The Zwicky Transient Facility, based at the Palomar Observatory in San Diego County, has identified over a thousand new objects and phenomena in the night sky, including more than 1,100 new supernovae and 50 near-Earth asteroids, as well as binary star systems and black holes. Operated by Caltech, the ZTF is a public-private partnership between the National Science Foundation and a consortium of nine other institutions around the globe, including the University of Washington. The ZTF collaboration’s six latest papers, which describe these discoveries as well as the ZTF’s data mining, sorting and alert systems, have been accepted for publication in the journal Publications of the Astronomical Society of the Pacific.

Eric Bellm, the ZTF survey scientist and a research assistant professor of astronomy at UW, is lead author on a paper describing the ZTF’s technical systems and major findings since the survey began on March 20, 2018. Maria Patterson, a data scientist formerly with the UW Department of Astronomy’s DIRAC Institute, is lead author on another paper describing the ZTF’s alert system for notifying science teams of possible new objects in the sky or significant changes to existing objects.

“The ZTF mission is to identify changes in the night sky and alert the astronomical field of these discoveries as quickly as possible,” said Bellm, who is also a fellow with the DIRAC Institute. “The results and specifications reported in these six papers demonstrate that the ZTF has in place a pipeline to identify new objects, as well as analyze and disseminate information about them quickly to the astronomy community.”

Science teams need quick alerts so that they could, if needed, arrange for follow-up observations of individual objects by other observatories, Bellm added.

The ZTF accomplishes its survey goals through a digital camera, consisting of 16 charge-coupled devices, mounted to the 48-inch-aperture Samuel Oschin Telescope at Palomar. A single image from the camera covers an area about 240 times the size of the moon; in just one night, the ZTF could image the entire night sky visible from the Northern Hemisphere. So far, the ZTF camera has imaged more than 1 billion stars in our galaxy alone. By comparing new images to old, the ZTF can identify objects that are new, such as a supernova lighting up for the first time, or changes to existing objects, such as a star brightening in luminosity.

The ZTF undertakes surveys for public agencies such as the National Science Foundation, as well as private entities. The sheer volume of data generated by the ZTF necessitated a new approach to data analysis and alerts, according to Bellm.

“Every image that the ZTF takes contributes to at least one survey,” said Bellm. “We needed to put an automated alert system in place that would inform the relevant survey teams — in near-real time — of every potential change or new object that the ZTF would uncover, which could be more than a million in a single night.” Patterson, Bellm and other UW scientists — including Mario Juric, associate professor of astronomy and senior data fellow with the eScience Institute — led the effort within the ZTF to craft the automated alert system. They utilized two open-source technologies: Kafka, a real-time data-streaming platform, and Avro, a framework to serialize data for transmission and storage. The completed alert system, which was first deployed in June 2018, has successfully generated and distributed up to 1.2 million ZTF alerts each night — with each alert going out to survey teams approximately 10 seconds after it was automatically generated.

“Through these alert systems, the ZTF is sharing every change it finds with our survey partners,” said Bellm. “They are receiving every bit of data.”

Survey partners, in turn, are experimenting with machine-learning classification systems and other analysis tools to sort through the alerts. The ZTF’s alert system is a proving ground for future “automated, time-domain astronomy” missions such as the Large Synoptic Survey Telescope, said Bellm. The LSST, which is expected to begin its sky surveys in 2022, should generate about 10 million alerts per night, which is about 10 times the maximum alert volume of the ZTF. But the ZTF alert system could form the basis of a scaled-up alert pipeline for the LSST, according to Bellm.

“We are very pleased with the opportunities that the ZTF mission has provided us,” said Bellm. “It is reassuring to know that we have the tools at hand today that are useful not only for ongoing surveys at the ZTF, but also future missions like the LSST.”

Shedding Light On The Science Of Auroral Breakups

Auroras, also known as Northern or Southern lights depending on whether they occur near the North or South Pole, are natural displays of light in the Earth’s sky. Typically these lights are dimly present at night. However, sometimes these otherwise faint features explode in brightness and can even break up into separate glowing hallmarks, appearing as spectacular bursts of luminous manifestations. This striking and picturesque phenomenon is known as an auroral breakup.

Now, Japanese scientists have quantitatively confirmed how energetic this phenomenon can be. Using a combination of cutting-edge ground-based technology and new space-borne observations, they have demonstrated the essential role of an auroral breakup in ionizing the deep atmosphere. The research furthers our understanding of one of the most visually stunning natural phenomena.

The findings were published in Earth, Planets and Space on January 23, 2019.

The sun fires beams of charged particles, or plasma, toward Earth. Also referred to as solar winds, this plasma is mostly made up of electrons, protons and alpha particles. When these particles interact with the Earth’s magnetic field, electrical currents are carried by electrons into the Earth’s atmosphere. This reaction between the electrons and their atmospheric constituents emits light of varying color and complexity, visible as an aurora. However, little is known about how energetic the electrons can be when these lights explode into the stunning lightshows known as auroral breakups. So far, the assumption has been that electrons of a specific energy level are responsible for this rare phenomenon.

In the new study, the scientists report that, contrary to conventional thinking, a specific kind of electrons with much higher energy, called radiation belt electrons, are involved in the auroral breakup. Named after their location in the Earth’s radiation belt, radiation belt electrons had not been clearly associated with auroral breakups before. The research team based their conclusions on a dataset collected via advanced technology and simulations.

“Radiation belt electrons are released from the Earth’s magnetic field and charge the mesosphere during auroral breakup. This fact was quantitatively confirmed by both cutting-edge ground-based and new space-borne observations,” adds Ryuho Kataoka, Ph.D., associate professor at the National Institute of Polar Research and the corresponding author. “This study also provides a good example how Arase satellite and PANSY radar can collaborate to understand the connection between space and atmosphere.”

In their future research endeavors, the Professor Kataoka and his team hope to understand how the radiation belt electrons are released during the short-lasting period of auroral breakup. “The ultimate goal is to understand the interplay between auroras and radiation belts,” Professor Kataoka adds.

This research was supported by several Japan Society for the Promotion of Science-Kakenhi grants.

A Better Eyeshot Of The Makeup Of Ancient Meteorites

A team of Japanese and American scientists has visualized meteorite components at resolution powers much higher than ever before. Their efforts resulted in a much better look at — and enhanced understanding of — substances inside carbonaceous chondrites, the organic-containing meteorites that land on Earth. These substances include hydrogen, carbon, nitrogen and water, all of which are needed for life.

The study was published online on January 2, 2019 in Proceedings of the National Academy of Sciences (PNAS).

Carbonaceous chondrites are made of materials such as rocks, organics, ice, and fine grain dust, most of which are formed in the Solar System. The origin of organic matter that is found in meteorites dates back to the formation of the Solar System, or approximately 4.5 billion years ago. Therefore, when found on Earth and analyzed in detail, these carbonaceous chondrites are helpful for understanding the history of the Solar System, the formation of organic compounds, the presence of water on Earth, and ultimately the origin of life.

Being able to visualize organic and inorganic components of meteorites that have landed on Earth is important because it enables researchers to understand the effects of external factors — such as water and temperature — on them. More specifically, a method that enables researchers to better see and analyze the molecular structures ultimately helps them understand the spatial relationships between organic matter and minerals. This is vital for tracing the formation as well as the evolution of organic matter and ultimately understand the history of the formation of the Solar System. Also, understanding the origin of meteorites is crucial for determining the origins of both water and life on the planet.

However, studies to date have been limited with their methods as well as microscopy that has provided images at much lower resolutions. Therefore, formations and evolutions of extraterrestrial organic matter have thus far remained fairly unknown and have only been analyzed after extraction, which is a complicated multi-step process that is prone to many types of methodological errors.

“Researchers have recently mostly conducted analysis for organic matter to see the distributions and associations with inorganic compounds that may help us understand chemistry such as mineral catalyzed synthesis of organic matter, during alteration processes in the meteorite parent asteroids and historic dust processes in the early Solar System. However, since the components of meteorites are very fine, microscopic techniques to analyze such distributions and associations are limited,” says Yoko Kebukawa, Ph.D., an Associate Professor at the Faculty of Engineering, Yokohama National University in Japan and the corresponding author of the paper.

Specific to this research, the focus has been on visualizing components of carbonaceous chondrites via a powerful microscopy method that provides images of meteorite components at much better resolutions. This method, atomic force microscopy-based infrared spectroscopy (AFM-IR) enabled the researchers to view the components of two carbonaceous chondrites, the Murchison meteorite and the Bell meteorite at much higher resolutions. This, in turn, provided much more detailed images than those that have been obtained thus far.

“The AFM-IR technique enabled us to overcome the limitation of poor spatial resolution of infrared spectroscopy to see the fine details of organic matter as it is distributed in meteorites and associations of minerals,” Kebukawa adds.

In the future, the team plans to focus on the roles of minerals in the formations and evolution of organic matter in meteorites during external processes that affect the bodies they come from. According to Kebukawa, “This requires two things, namely analyses of meteorites that have been altered in several ways as well as proper experimental simulations of these alteration processes that will enable the aforementioned methods.”

Life Thrived On Earth 3.5 Billion Years Ago, Research Suggests

3.5 billion years ago Earth hosted life, but was it barely surviving, or thriving? A new study carried out by a multi institutional team with leadership including the Earth-Life Science Institute (ELSI) of Tokyo Institute of Technology (Tokyo Tech) provides new answers to this question. Microbial metabolism is recorded in billions of years of sulfur isotope ratios that agree with this study’s predictions, suggesting life throve in the ancient oceans. Using this data, scientists can more deeply link the geochemical record with cellular states and ecology.

Scientists want to know how long life has existed on Earth. If it has been around for almost as long as the planet, this suggests it is easy for life to originate and life should be common in the Universe. If it takes a long time to originate, this suggests there were very special conditions that had to occur. Dinosaurs, whose bones are presented in museums around the world, were preceded by billions of years by microbes. While microbes have left some physical evidence of their presence in the ancient geological record, they do not fossilize well, thus scientists use other methods for understanding whether life was present in the geological record.

Presently, the oldest evidence of microbial life on Earth comes to us in the form of stable isotopes. The chemical elements charted on the periodic are defined by the number of protons in their nuclei, for example, hydrogen atoms have one proton, helium atoms have two, carbon atoms contain six. In addition to protons, most atomic nuclei also contain neutrons, which are about as heavy as protons, but which don’t bear an electric charge. Atoms which contain the same number of protons, but variable numbers of neutrons are known as isotopes. While many isotopes are radioactive and thus decay into other elements, some do not undergo such reactions; these are known as “stable” isotopes. For example, the stable isotopes of carbon include carbon 12 (written as 12C for short, with 6 protons and 6 neutrons) and carbon 13 (13C, with 6 protons and 7 neutrons).

All living things, including humans, “eat and excrete.” That is to say, they take in food and expel waste. Microbes often eat simple compounds made available by the environment. For example, some are able to take in carbon dioxide (CO2) as a carbon source to build their own cells. Naturally occurring CO2 has a fairly constant ratio of 12C to 13C. However, 12CO2 is about 2 % lighter than 13CO2, so 12CO2 molecules diffuse and react slightly faster, and thus the microbes themselves become “isotopically light,” containing more 12C than 13C, and when they die and leave their remains in the fossil record, their stable isotopic signature remains, and is measurable. The isotopic composition, or “signature,” of such processes can be very specific to the microbes that produce them.

Besides carbon there are other chemical elements essential for living things. For example, sulfur, with 16 protons, has three naturally abundant stable isotopes, 32S (with 16 neutrons), 33S (with 17 neutrons) and 34S (with 18 neutrons). Sulfur isotope patterns left behind by microbes thus record the history of biological metabolism based on sulfur-containing compounds back to around 3.5 billion years ago. Hundreds of previous studies have examined wide variations in ancient and contemporary sulfur isotope ratios resulting from sulfate (a naturally occurring sulfur compound bonded to four oxygen atoms) metabolism. Many microbes are able to use sulfate as a fuel, and in the process excrete sulfide, another sulfur compound. The sulfide “waste” of ancient microbial metabolism is then stored in the geological record, and its isotope ratios can be measured by analyzing minerals such as the FeS2 mineral pyrite.

This new study reveals a primary biological control step in microbial sulfur metabolism, and clarifies which cellular states lead to which types of sulfur isotope fractionation. This allows scientists to link metabolism to isotopes: by knowing how metabolism changes stable isotope ratios, scientists can predict the isotopic signature organisms should leave behind. This study provides some of the first information regarding how robustly ancient life was metabolizing. Microbial sulfate metabolism is recorded in over a three billion years of sulfur isotope ratios that are in line with this study’s predictions, which suggest life was in fact thriving in the ancient oceans. This work opens up a new field of research, which ELSI Associate Professor Shawn McGlynn calls “evolutionary and isotopic enzymology.” Using this type of data, scientists can now proceed to other elements, such as carbon and nitrogen, and more completely link the geochemical record with cellular states and ecology via an understanding of enzyme evolution and Earth history.

Dynamic Atmospheres Of Uranus, Neptune

During its routine yearly monitoring of the weather on our solar system’s outer planets, NASA’s Hubble Space Telescope has uncovered a new mysterious dark storm on Neptune and provided a fresh look at a long-lived storm circling around the north polar region on Uranus.

Like Earth, Uranus and Neptune have seasons, which likely drive some of the features in their atmospheres. But their seasons are much longer than on Earth, spanning decades rather than months.

The new Hubble view of Neptune shows the dark storm, seen at top center. Appearing during the planet’s southern summer, the feature is the fourth and latest mysterious dark vortex captured by Hubble since 1993. Two other dark storms were discovered by the Voyager 2 spacecraft in 1989 as it flew by the remote planet. Since then, only Hubble has had the sensitivity in blue light to track these elusive features, which have appeared and faded quickly. A study led by University of California, Berkeley, undergraduate student Andrew Hsu estimated that the dark spots appear every four to six years at different latitudes and disappear after about two years.

Hubble uncovered the latest storm in September 2018 in Neptune’s northern hemisphere. The feature is roughly 6,800 miles across.

To the right of the dark feature are bright white “companion clouds.” Hubble has observed similar clouds accompanying previous vortices. The bright clouds form when the flow of ambient air is perturbed and diverted upward over the dark vortex, causing gases to freeze into methane ice crystals. These clouds are similar to clouds that appear as pancake-shaped features when air is pushed over mountains on Earth (though Neptune has no solid surface). The long, thin cloud to the left of the dark spot is a transient feature that is not part of the storm system.

It’s unclear how these storms form. But like Jupiter’s Great Red Spot, the dark vortices swirl in an anti-cyclonic direction and seem to dredge up material from deeper levels in the ice giant’s atmosphere.

The Hubble observations show that as early as 2016, increased cloud activity in the region preceded the vortex’s appearance. The images indicate that the vortices probably develop deeper in Neptune’s atmosphere, becoming visible only when the top of the storm reaches higher altitudes.

The snapshot of Uranus, like the image of Neptune, reveals a dominant feature: a vast bright stormy cloud cap across the north pole.

Scientists believe this new feature is a result of Uranus’ unique rotation. Unlike every other planet in the solar system, Uranus is tipped over almost onto its side. Because of this extreme tilt, during the planet’s summer the Sun shines almost directly onto the north pole and never sets. Uranus is now approaching the middle of its summer season, and the polar-cap region is becoming more prominent. This polar hood may have formed by seasonal changes in atmospheric flow.

Near the edge of the polar storm is a large, compact methane-ice cloud, which is sometimes bright enough to be photographed by amateur astronomers. A narrow cloud band encircles the planet north of the equator. It is a mystery how bands like these are confined to such narrow widths, because Uranus and Neptune have very broad westward-blowing wind jets.

Both planets are classified as ice giant planets. They have no solid surface but rather mantles of hydrogen and helium surrounding a water-rich interior, itself perhaps wrapped around a rocky core. Atmospheric methane absorbs red light but allows blue-green light to be scattered back into space, giving each planet a cyan hue.

The new Neptune and Uranus images are from the Outer Planet Atmospheres Legacy (OPAL) program, a long-term Hubble project, led by Amy Simon of NASA’s Goddard Space Flight Center in Greenbelt, Maryland, that annually captures global maps of our solar system’s outer planets when they are closest to Earth in their orbits. OPAL’s key goals are to study long-term seasonal changes, as well as capture comparatively transitory events, such as the appearance of Neptune’s dark spot. These dark storms may be so fleeting that in the past some of them may have appeared and faded during multi-year gaps in Hubble’s observations of Neptune. The OPAL program ensures that astronomers won’t miss another one.

These images are part of a scrapbook of Hubble snapshots of Neptune and Uranus that track the weather patterns over time on these distant, cold planets. Just as meteorologists cannot predict the weather on Earth by studying a few snapshots, astronomers cannot track atmospheric trends on solar system planets without regularly repeated observations. Astronomers hope that Hubble’s long-term monitoring of the outer planets will help them unravel the mysteries that still persist about these faraway worlds.

Analyzing the weather on these worlds also will help scientists better understand the diversity and similarities of the atmospheres of solar-system planets, including Earth.

New Research Sheds Light on Lost Continent Zealandia

New data collected by University of Wyoming researchers and others point to a newly defined mantle domain in a remote part of the Southern Ocean.

UW Department of Geology and Geophysics Professor Ken Sims and recent Ph.D. graduate Sean Scott are co-authors of an article, “An isotopically distinct Zealandia-Antarctic mantle domain in the Southern Ocean,” published by the scientific journal Nature Geoscience in January.

Zealandia is an almost entirely submerged mass of continental crust that sank after breaking away from Australia 60–85 million years ago, having separated from Antarctica between 85 and 130 million years ago. It has been described as a lost continental, a microcontinent, and submerged continent. The name and concept for Zealandia was proposed by Bruce Luyendyk in 1995.

The land mass may have been completely submerged about 23 million years ago, and most of it (93%) remains submerged beneath the Pacific Ocean. With a total area of approximately 4,920,000 km2 (1,900,000 sq mi), it is the world’s largest current microcontinent, more than twice the size of the next-largest microcontinent Mauritia, and more than half the size of the Australian continent.

As such, and due to other geological considerations, such as crustal thickness and density, it is arguably a continent in its own right. This was the argument which made news in 2017, when geologists from New Zealand, New Caledonia, and Australia concluded that Zealandia fulfills all the requirements to be considered a continent, rather than a microcontinent or continental fragment.