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The Next End of the World | C.I.A. Classified

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Earth Catastrophe Cycle | Stories to Tell

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Earth Catastrophe Cycle | SOLAR MICRONOVA

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Earth Catastrophe Cycle | SOLAR MICRONOVA II

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Earth Catastrophe Cycle | Star-Metal Impactors

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Extraño Meteoro, Vórtice Polar, Ráfaga Solar

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Extraño Meteoro, Vórtice Polar, Ráfaga Solar

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Strangest Meteor, Polar Vortex, Ancient Solar Blast | S0 News Jan.5.2019

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Recurring Nova Z-Pinch, Cyclone | S0 News Jan.4.2019

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Erupción de Filamento, Ciclo Climático, Especial Anuncio

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Erupción de Filamento, Ciclo Climático, Especial Anuncio

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Filament Erupts, Climate Cycle, Special Announcement | S0 News Jan.3.2019

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Tornado, Records, Electric Earthquakes | S0 News Jan.1.2019

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Mancha Solar, gran Derrumbe, Destellos Estelares

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Sunspots Appear, Big Landslide, Stellar Flashes | S0 News Jan.2.2019

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Earth Catastrophe Cycle | Good Questions

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ALMA descubre una Protoestrella con un Disco inclinado

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ALMA descubre una Protoestrella con un Disco inclinado

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Scientific Paper

Using the Atacama Large Millimeter/submillimeter Array (ALMA) in Chile, researchers have observed, for the first time, a warped disk around an infant protostar that formed just several tens of thousands of years ago. This implies that the misalignment of planetary orbits in many planetary systems, including our own, may be caused by distortions in the planet-forming disk early in their existence.

The planets in the Solar System orbit the Sun in planes that are at most about seven degrees offset from the equator of the Sun itself. It has been known for some time that many extrasolar systems have planets that are not lined up in a single plane or with the equator of the star. One explanation for this is that some of the planets might have been affected by collisions with other objects in the system or by stars passing by the system, ejecting them from the initial plane.

However, the possibility remained that the formation of planets out of the normal plane was actually caused by a warping of the star-forming cloud out of which the planets were born. Recently, images of protoplanetary disks, rotating disks where planets form around a star, have in fact showed such warping. But it was still unclear how early this happened.

In the latest findings, published in Nature, the group from the RIKEN Cluster for Pioneering Research (CPR) and Chiba University in Japan have discovered that L1527; an infant protostar still embedded within a cloud, has a disk that has two parts, an inner one rotating in one plane, and an outer one in a different plane. The disk is very young and still growing. L1527, which is about 450 light years away in the Taurus Molecular Cloud, is a good object for study as it has a disk that is nearly edge-on to our view.

According to Nami Sakai, who led the research group, "this observation shows that it is conceivable that the misalignment of planetary orbits can be caused by a warp structure formed in the earliest stages of planetary formation. We will have to investigate more systems to find out if this is a common phenomenon or not."

The remaining question is what caused the warping of the disk. Sakai suggests two reasonable explanations. "One possibility," she says, "is that irregularities in the flow of gas and dust in the protostellar cloud are still preserved and manifest themselves as the warped disk. A second possibility is that the magnetic field of the protostar is in a different plane from the rotational plane of the disk, and that the inner disk is being pulled into a different plane from the rest of the disk by the magnetic field." She says they plan further work to determine which is responsible for the warping of the disk.

Additional Information

This research has been published in Nature (Advanced Online Publication) under the title " Warped disk around an infant protostar " by N. Sakai et al.

The Atacama Large Millimeter/submillimeter Array (ALMA), an international astronomy facility, is a partnership of the European Southern Observatory (ESO), the U.S. National Science Foundation (NSF) and the National Institutes of Natural Sciences (NINS) of Japan in cooperation with the Republic of Chile. ALMA is funded by ESO on behalf of its Member States, by NSF in cooperation with the National Research Council of Canada (NRC) and the Ministry of Science and Technology (MOST) in Taiwan and by NINS in cooperation with the Academia Sinica (AS) in Taiwan and the Korea Astronomy and Space Science Institute (KASI).

ALMA construction and operations are led by ESO on behalf of its Member States; by the National Radio Astronomy Observatory (NRAO), managed by Associated Universities, Inc. (AUI), on behalf of North America; and by the National Astronomical Observatory of Japan (NAOJ) on behalf of East Asia. The Joint ALMA Observatory (JAO) provides the unified leadership and management of the construction, commissioning and operation of ALMA.

RIKEN is Japan's largest research institute for basic and applied research. Over 2500 papers by RIKEN researchers are published every year in leading scientific and technology journals covering a broad spectrum of disciplines including physics, chemistry, biology, engineering, and medical science. RIKEN's research environment and strong emphasis on interdisciplinary collaboration and globalization has earned a worldwide reputation for scientific excellence.

Images

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ALMA Discover Early Protostar With a Warped Disk

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Scientific Paper Using the Atacama Large Millimeter/submillimeter Array (ALMA) in Chile, researchers have observed, for the first time, a warped disk around an infant protostar that formed just several tens of thousands of years ago. This implies that the misalignment of planetary orbits in many planetary systems, including our own, may be caused by distortions in the planet-forming disk early in their existence.

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Estructura Eléctrica de la Litosfera  desde el Crotón de Río de Plata a la Cuenca sedimentaria del Paraná ... 

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Estructura Eléctrica de la Litosfera  desde el Crotón de Río de Plata a la Cuenca sedimentaria del Paraná ... 

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Journal of Advances in Modeling Earth Systems (JAMES)

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Exploración con éxito de Ultima Thule por la misión New Horizons

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Exploración con éxito de Ultima Thule por la misión New Horizons

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The New Horizons spacecraft launched on January 19, 2006 - beginning its odyssey to Pluto and the Kuiper Belt. New Horizons now continues on its unparalleled journey of exploration with the close flyby of a Kuiper Belt object called 2014 MU69 - nicknamed Ultima Thule - on January 1, 2019.

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Earth Catastrophe Cycle | Plasma Formations

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http://articles.adsabs.harvard.edu/cgi-bin/nph-iarticle_query?1989ApJ...337..927S&amp;data_type=PDF_HIGH&amp;whole_paper=YES&amp;type=PRINTER&amp;filetype=.pdf

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Blot Echoes (M4+ & Profundidad > 80km)

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Centro de Clima Espacial - Ionosfera , Alemania (SWACI)

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Centro de Clima Espacial - Ionosfera , Alemania (SWACI)

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Centro de Clima Espacial - Ionosfera , Alemania (SWACI)

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Centro de Clima Espacial - Ionosfera , Alemania (SWACI)

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Evidencia de una gran explosión en la prehistoria

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Evidencia de una gran explosión en la prehistoria

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The New Horizons spacecraft launched on January 19, 2006 - beginning its odyssey to Pluto and the Kuiper Belt. New Horizons now continues on its unparalleled journey of exploration with the close flyby of a Kuiper Belt object called 2014 MU69 - nicknamed Ultima Thule - on January 1, 2019.

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A Chinese probe has made a historic touch-down on the far side of the Moon, according to the country's state-run media. It is the first time a probe has visited the region, 60 years after an orbiter gave humans their first look at the area.

Chang'e-4 reportedly landed inside the Von Kármán Crater at 2:26 ut on 3 January, and has sent back its first images. At 14:22 ut the mission's 140-kilogram Yutu2 rover drove down a ramp and onto the lunar terrain, according to images widely circulated on social media.

As the Moon's far side is permanently hidden from Earth, the news of Chang'e-4's successful landing was relayed by a spacecraft called Queqiao. It has been circling around a gravitationally stable point about 60,000 kilometres beyond the Moon since it launched in May.

The far-side landing location also meant that during the final phases of the approach, Chang'e-4 was on its own, and could not be operated remotely. Starting from an altitude of 15 kilometres, the probe used a rocket booster to brake and briefly hover. Meanwhile, an on-board camera and a laser ranging system scanned the terrain to avoid boulders.

The Chinese space programme has kept many details about the mission secret - including the planned timing of the landing - even from scientists who collaborated with it. Before the touch-down, Robert Wimmer-Schweingruber, a physicist at the University of Kiel in Germany who has a radiation-detection experiment on the lander, said that he expected to find out about the landing from Chinese news sites.

Chang'e-4 launched on 8 December and entered a highly elongated lunar orbit 4 days later. It then manoeuvred itself into a lower orbit. Mission management reportedly selected a landing site inside the relatively flat, 186-kilometre-wide Von Kármán Crater, which sits inside the much larger South Pole-Aitken Basin.

Unexplored territory

The basin - which is more than 2,500 kilometres wide - is thought to be the oldest of the Moon's large, deep-impact basins, and it is the only such feature on the orb's far side. Studying the basin has long been a top priority for Solar System researchers.

The basin﻿ is thought to have formed when a large asteroid hit the Moon towards the beginning of the Late Heavy Bombardment period, around 3.8 billion years ago. An accurate dating of the basin's formation could reveal whether this epoch of battering - which must have affected Earth as well as the Moon - stretched over hundreds of millions of years or was concentrated in a relatively brief time.

After the successful Moon landings in the 1970s, some began to take a "been there, done that" view of the Moon, says Jeffrey Taylor, a lunar scientist at the University of Hawai'i in Honolulu. But China's venture to the far side shows otherwise, he says. "We have not done it all or gone everywhere on the Moon." Still, solving the mysteries of lunar history will require collecting samples and returning them to Earth for analysis, he adds.

Because the Moon's rotation around its axis is precisely synchronized with its orbit owing to 'tidal locking', humans had no idea what the far side of the Moon looked like until the Soviet Union's Luna 3 probe sent back the first shots of it in 1959. Luna 3 revealed a region pockmarked by many more craters than the near side - and virtually devoid of the 'maria', or seas of solidified lava, which dominate the familiar near side. (Apollo 11 landed on one such mare, the Sea of Tranquility.)

In the following decades, other probes followed up with detailed topographical and gravimetric mapping of the full lunar surface, but no craft has landed on the far side until now. (A NASA probe crash-landed on the far side in 1962.) Studying the region from up close could provide clues to why it is so different.

Historic step

"The Chang'e-4 mission is an historic step in the Chinese lunar exploration programme and in international scientific exploration of the Moon," says Jim Head, a planetary scientist at Brown University in Providence, Rhode Island, and a veteran of NASA's Apollo programme. The mission will open up the 'Luna Incognita' - the unknown Moon - to surface exploration for the first time, he says.

Chang'e-4 and its 6-wheeled rover carry instruments that will do a range of experiments, including radio measurements of the early Universe; a study of the radiation environment of the lunar surface, led by Wimmer-Schweingruber; deep scans with a ground-penetrating radar; and analyses of the geology of the surface with an imaging spectrometer. Chang'e 4 also carries a small, climate-controlled environment with potato and Arabidopsis seeds and silkworm cocoons.

Chang'e-4 and its rover were originally built as a back-up to the previous lunar mission, Chang'e-3, which went successfully in 2013. China's next Moon trip, Chang'e-5, will aim to return a sample of lunar rock to Earth, and is due to launch later this year.
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China becomes first nation to land on the Moon's far side (Updated)

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A Chinese probe has made a historic touch-down on the far side of the Moon, according to the country's state-run media. It is the first time a probe has visited the region, 60 years after an orbiter gave humans their first look at the area.

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New research led by astrophysicists at Durham University, UK, predicts that the Large Magellanic Cloud (LMC) could hit the Milky Way in two billion years' time.

The collision could occur much earlier than the predicted impact between the Milky Way and another neighbouring galaxy, Andromeda, which scientists say will hit our galaxy in eight billion years.

The catastrophic coming together with the Large Magellanic Cloud could wake up our galaxy's dormant black hole, which would begin devouring surrounding gas and increase in size by up to ten times.

As it feeds, the now-active black hole would throw out high-energy radiation and while these cosmic fireworks are unlikely to affect life on Earth, the scientists say there is a small chance that the initial collision could send our Solar System hurtling into space.

The findings are published today (Friday, 4 January) in the journal Monthly Notices of the Royal Astronomical Society.

Galaxies like our own Milky Way are surrounded by a group of smaller satellite galaxies that orbit around them, in a similar way to how bees move around a hive.

Typically, these satellite galaxies have a quiet life and orbit around their hosts for many billions of years. However, from time to time, they sink to the centre, collide and are devoured by their host galaxy.

The Large Magellanic Cloud is the brightest satellite galaxy of the Milky Way and only entered our neighbourhood about 1.5 billion years ago. It sits about 163,000 light years from the Milky Way.

Until recently astronomers thought that it would either orbit the Milky Way for many billions of years, or, since it moves so fast, escape from our galaxy's gravitational pull.

However, recent measurements indicate that the Large Magellanic Cloud has nearly twice as much dark matter than previously thought. The researchers say that since it has a larger than expected mass, the Large Magellanic Cloud is rapidly losing energy and is doomed to collide with our galaxy.

The research team, led by scientists at Durham University's Institute for Computational Cosmology working with the University of Helsinki, in Finland, used the EAGLE galaxy formation supercomputer simulation to predict the collision.

Lead author Dr Marius Cautun, a postdoctoral fellow in Durham University's Institute for Computational Cosmology, said: "While two billion years is an extremely long time compared to a human lifetime, it is a very short time on cosmic timescales.

"The destruction of the Large Magellanic Cloud, as it is devoured by the Milky Way, will wreak havoc with our galaxy, waking up the black hole that lives at its centre and turning our galaxy into an 'active galactic nucleus' or quasar.

"This phenomenon will generate powerful jets of high energy radiation emanating from just outside the black hole. While this will not affect our Solar System, there is a small chance that we might not escape unscathed from the collision between the two galaxies which could knock us out of the Milky Way and into interstellar space."

The collision between the Large Magellanic Cloud and the Milky Way could be spectacular, the researchers say.

Co-author Professor Carlos Frenk, Director of the Institute for Computational Cosmology, Durham University, said: "Beautiful as it is, our Universe is constantly evolving, often through violent events like the forthcoming collision with the Large Magellanic Cloud.

"Barring any disasters, like a major disturbance to the Solar System, our descendants, if any, are in for a treat: a spectacular display of cosmic fireworks as the newly awakened supermassive black hole at the centre of our galaxy reacts by emitting jets of extremely bright energetic radiation."

According to the researchers, the merger of the two galaxies could be long overdue in cosmic terms.

Dr Alis Deason, of Durham University's Institute for Computational Cosmology, said: "We think that up to now our galaxy has had only a few mergers with very low mass galaxies.

"This represents very slim pickings when compared to nearby galaxies of the same size as the Milky Way. For example, our nearest neighbour, the Andromeda galaxy, devoured galaxies weighing nearly 30 times more than those consumed by the Milky Way.

"Therefore, the collision with the Large Magellanic Cloud is long overdue and it is needed to make our galaxy typical."

###

The research was funded by the Science and Technology Facilities Council, the European Research Council, the Royal Society and the Academy of Finland.

Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.

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Catastrophic galactic collision could send solar system flying into space

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New research led by astrophysicists at Durham University, UK, predicts that the Large Magellanic Cloud (LMC) could hit the Milky Way in two billion years' time. The collision could occur much earlier than the predicted impact between the Milky Way and another neighbouring galaxy, Andromeda, which scientists say will hit our galaxy in eight billion years.

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Dark matter on the move | University of Surrey

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Professor Justin Read, lead author of the study and Head of the Department of Physics at the University of Surrey, said: "We found a truly remarkable relationship between the amount of dark matter at the centres of these tiny dwarfs, and the amount of star formation they have experienced over their lives.

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Light from the plumes and fires of Io on Earth's darkest night

Dec. 31, 2018 - A team of space scientists has captured new images of a volcanic plume on Jupiter's moon Io during the Juno mission's 17th flyby of the gas giant. On Dec. 21, during winter solstice, four of Juno's cameras captured images of the Jovian moon Io, the most volcanic body in our solar system. JunoCam, the Stellar Reference Unit (SRU), the Jovian Infrared Auroral Mapper (JIRAM) and the Ultraviolet Imaging Spectrograph (UVS) observed Io for over an hour, providing a glimpse of the moon's polar regions as well as evidence of an active eruption.

"We knew we were breaking new ground with a multi-spectral campaign to view Io's polar region, but no one expected we would get so lucky as to see an active volcanic plume shooting material off the moon's surface," said Scott Bolton, principal investigator of the Juno mission and an associate vice president of Southwest Research Institute's Space Science and Engineering Division. "This is quite a New Year's present showing us that Juno has the ability to clearly see plumes."

JunoCam acquired the first images on Dec. 21 at 12:00, 12:15 and 12:20 coordinated universal time (UTC) before Io entered Jupiter's shadow. The Images show the moon half-illuminated with a bright spot seen just beyond the terminator, the day-night boundary.

"The ground is already in shadow, but the height of the plume allows it to reflect sunlight, much like the way mountaintops or clouds on the Earth continue to be lit after the sun has set," explained Candice Hansen-Koharcheck, the JunoCam lead from the Planetary Science Institute.

At 12:40 UTC, after Io had passed into the darkness of total eclipse behind Jupiter, sunlight reflecting off nearby moon Europa helped to illuminate Io and its plume. SRU images released by SwRI depict Io softly illuminated by moonlight from Europa. The brightest feature on Io in the image is thought to be a penetrating radiation signature, a reminder of this satellite's role in feeding Jupiter's radiation belts, while other features show the glow of activity from several volcanoes. "As a low-light camera designed to track the stars, the SRU can only observe Io under very dimly lit conditions. Dec. 21 gave us a unique opportunity to observe Io's volcanic activity with the SRU using only Europa's moonlight as our lightbulb," said Heidi Becker, lead of Juno's Radiation Monitoring Investigation, at NASA's Jet Propulsion Laboratory.

Sensing heat at long wavelengths, the JIRAM instrument detects hotspots in the daylight and at night.

"Though Jupiter's moons are not JIRAM's primary objectives, every time we pass close enough to one of them, we take advantage of the opportunity for an observation," said Alberto Adriani, a researcher at Italy's National Institute of Astrophysics. "The instrument is sensitive to infrared wavelengths, which are perfect to study the volcanism of Io. This is one of the best images of Io that JIRAM has been able to collect so far."

The latest images can lead to new insights into the gas giant's interactions with its five moons, causing phenomena such as Io's volcanic activity or freezing of the moon's atmosphere during eclipse, added Bolton. JIRAM recently documented Io's volcanic activity before and after eclipse. Io's volcanoes were discovered by NASA's Voyager spacecraft in 1979. Io's gravitational interaction with Jupiter drives the moon's volcanoes, which emit umbrella-like plumes of SO2 gas and produce extensive basaltic lava fields.

The recent Io images were captured at the halfway point of the mission, which is scheduled to complete a map of Jupiter in July 2021. Launched in 2011, Juno arrived at Jupiter in 2016. The spacecraft orbits Jupiter every 53 days, studying its auroras, atmosphere and magnetosphere.

The solar-powered Juno features eight scientific instruments designed to study Jupiter's interior structure, atmosphere and magnetosphere. NASA's Jet Propulsion Laboratory manages the Juno mission for Bolton. Juno is part of the New Frontiers Program, which is managed at Marshall Space Flight Center in Huntsville, Alabama, for NASA's Science Mission Directorate. Lockheed Martin Space built the spacecraft, and SwRI provided two Juno instruments to study the massive Jovian aurora.

For more information, visit Space Science or contact Robert Crowe, +1 210 522 4630, Communications Department, Southwest Research Institute, PO Drawer 28510, San Antonio, TX 78228-0510.

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Juno mission captures images of volcanic plumes on Jupiter's moon Io

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Dec. 31, 2018 - A team of space scientists has captured new images of a volcanic plume on Jupiter's moon Io during the Juno mission's 17th flyby of the gas giant. On Dec. 21, during winter solstice, four of Juno's cameras captured images of the Jovian moon Io, the most volcanic body in our solar system.

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The New Horizons spacecraft launched on January 19, 2006 - beginning its odyssey to Pluto and the Kuiper Belt. New Horizons now continues on its unparalleled journey of exploration with the close flyby of a Kuiper Belt object called 2014 MU69 - nicknamed Ultima Thule - on January 1, 2019.

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The Sahara desert is one of the harshest, most inhospitable places on the planet, covering much of North Africa in some 3.6 million square miles of rock and windswept dunes. But it wasn't always so desolate and parched. Primitive rock paintings and fossils excavated from the region suggest that the Sahara was once a relatively verdant oasis, where human settlements and a diversity of plants and animals thrived.

Now researchers at MIT have analyzed dust deposited off the coast of west Africa over the the last 240,000 years, and found that the Sahara, and North Africa in general, has swung between wet and dry climates every 20,000 years. They say that this climatic pendulum is mainly driven by changes to the Earth's axis as the planet orbits the sun, which in turn affect the distribution of sunlight between seasons - every 20,000 years, the Earth swings from more sunlight in summer to less, and back again.

For North Africa, it is likely that, when the Earth is tilted to receive maximum summer sunlight with each orbit around the sun, this increased solar flux intensifies the region's monsoon activity, which in turn makes for a wetter, "greener" Sahara. When the planet's axis swings toward an angle that reduces the amount of incoming summer sunlight, monsoon activity weakens, producing a drier climate similar to what we see today.

"Our results suggest the story of North African climate is dominantly this 20,000-year beat, going back and forth between a green and dry Sahara," says David McGee, an associate professor in MIT's Department of Earth, Atmospheric and Planetary Sciences. "We feel this is a useful time series to examine in order to understand the history of the Sahara desert and what times could have been good for humans to settle the Sahara desert and cross it to disperse out of Africa, versus times that would be inhospitable like today."

McGee and his colleagues have published their results today in Science Advances.
A puzzling pattern
Each year, winds from the northeast sweep up hundreds of millions of tons of Saharan dust, depositing much of this sediment into the Atlantic Ocean, off the coast of West Africa. Layers of this dust, built up over hundreds of thousands of years, can serve as a geologic chronicle of North Africa's climate history: Layers thick with dust may indicate arid periods, whereas those containing less dust may signal wetter eras.

Scientists have analyzed sediment cores dug up from the ocean bottom off the coast of West Africa, for clues to the Sahara's climate history. These cores contain layers of ancient sediment deposited over millions of years. Each layer can contain traces of Saharan dust as well as the remains of life forms, such as the tiny shells of plankton.

Past analyses of these sediment cores have unearthed a puzzling pattern: It would appear that the Sahara shifts between wet and dry periods every 100,000 years - a geologic beat that scientists have linked to the Earth's ice age cycles, which seem to also come and go every 100,000 years. Layers with a larger fraction of dust seem to coincide with periods when the Earth is covered in ice, whereas less dusty layers appear during interglacial periods, such as today, when ice has largely receded.

But McGee says this interpretation of the sediment cores chafes against climate models, which show that Saharan climate should be driven by the region's monsoon season, the strength of which is determined by the tilt of the Earth's axis and the amount of sunlight that can fuel monsoons in the summer.

"We were puzzled by the fact that this 20,000-year beat of local summer insolation seems like it should be the dominant thing controlling monsoon strength, and yet in dust records you see ice age cycles of 100,000 years," McGee says.
Beats in sync
To get to the bottom of this contradiction, the researchers used their own techniques to analyze a sediment core obtained off the coast of West Africa by colleagues from the University of Bordeaux - which was drilled only a few kilometers from cores in which others had previously identified a 100,000-year pattern.

The researchers, led by first author Charlotte Skonieczny, a former MIT postdoc and now a professor at Paris-Sud University, examined layers of sediment deposited over the last 240,000 years. They analyzed each layer for traces of dust and measured the concentrations of a rare isotope of thorium, to determine how rapidly dust was accumulating on the seafloor.

Thorium is produced at a constant rate in the ocean by very small amounts of radioactive uranium dissolved in seawater, and it quickly attaches itself to sinking sediments. As a result, scientists can use the concentration of thorium in the sediments to determine how quickly dust and other sediments were accumulating on the seafloor in the past: During times of slow accumulation, thorium is more concentrated, while at times of rapid accumulation, thorium is diluted. The pattern that emerged was very different from what others had found in the same sediment cores.

"What we found was that some of the peaks of dust in the cores were due to increases in dust deposition in the ocean, but other peaks were simply because of carbonate dissolution and the fact that during ice ages, in this region of the ocean, the ocean was more acidic and corrosive to calcium carbonate," McGee says. "It might look like there's more dust deposited in the ocean, when really, there isn't."

Once the researchers removed this confounding effect, they found that what emerged was primarily a new "beat," in which the Sahara vacillated between wet and dry climates every 20,000 years, in sync with the region's monsoon activity and the periodic tilting of the Earth.

"We can now produce a record that sees through the biases of these older records, and so doing, tells a different story," McGee says. "We've assumed that ice ages have been the key thing in making the Sahara dry versus wet. Now we show that it's primarily these cyclic changes in Earth's orbit that have driven wet versus dry periods. It seems like such an impenetrable, inhospitable landscape, and yet it's come and gone many times, and shifted between grasslands and a much wetter environment, and back to dry climates, even over the last quarter million years."

This research was funded, in part, by the National Science Foundation.

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The Sahara desert is one of the harshest, most inhospitable places on the planet, covering much of North Africa in some 3.6 million square miles of rock and windswept dunes. But it wasn't always so desolate and parched.

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Dos Grandes Terremotos, Playas Nevadas, Riesgo Solar en Suecia  

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Dos Grandes Terremotos, Playas Nevadas, Riesgo Solar en Suecia  

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Two Big Quakes, Snowy Beaches, Sweden Solar Risk | S0 News Jan.6.2019

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Estudio sobre Rayos Gamma detectados en América y Asia

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Estudio sobre Rayos Gamma detectados en América y Asia

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JavaScript is disabled on your browser. Please enable JavaScript to use all the features on this page.

Highlights

*

Broadband lightning sferic signals are recorded for hundreds of TGFs observed in Americas and Asia, respectively.

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TGF-associated radio frequency lightning signals recorded in Americas and Asia exhibit similar features.

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The analysis of TGFs in Asia indicates that South China is an ideal region to study TGFs with coordinated ground observations.

Abstract

We examine the broadband (<1 Hz to 400 kHz) electromagnetic lightning signals associated with Terrestrial Gamma-ray Flashes (TGFs) detected by the Reuven Ramaty High Energy Solar Spectroscopic Imager (RHESSI) and the Gamma-ray Burst Monitor (GBM) on the Fermi Gamma-ray Space Telescope during 2010/2011. The TGF-associated lightning sferics are mainly recorded at two stations located near National Cheng-Kung University in Taiwan and near Duke University in the United States, respectively. The general features exhibited by the TGF-associated lightning sferics are consistent with previous findings that gamma-rays in TGFs are typically produced during a slow process that creates a considerable (but not necessarily) charge moment change within several milliseconds. In some cases, this slow process can be attributed to the upward negative leader during the initial stage of normal intra-cloud (IC) lightning, and it is usually punctuated by one or several fast discharges, the major one of which (i.e. TGF-related discharge) is closely involved in the gamma-ray production. The equivalent peak current of TGF-related discharges could be as high as >+500 kA, and the associated charge transfer is also considerable (typically >+20 C km). The observed complexity of TGF-associated lightning emissions can also be interpreted in the context of the initial development of normal IC lightning flashes, where the upward negative leader drives the millisecond-scale current and may also provide the seed electrons for avalanche multiplication in the upper part of active thunderstorms. Our analyses show that the thunderstorms in the land area of South China produce TGFs that can be readily observed by Fermi/GBM, and the future ground-based coordinated observations in this area would be rather promising to gain more insights into the physical mechanism of TGFs.

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A comparative study on the lightning sferics associated with terrestrial gamma-ray flashes observed in Americas and Asia

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JavaScript is disabled on your browser. Please enable JavaScript to use all the features on this page. * Broadband lightning sferic signals are recorded for hundreds of TGFs observed in Americas and Asia, respectively. * TGF-associated radio frequency lightning signals recorded in Americas and Asia exhibit similar features.

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Estudio sobre Períodos Históricos de Enfriamiento del Océano Pacífico

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Estudio sobre Períodos Históricos de Enfriamiento del Océano Pacífico

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The long memory of the Pacific Ocean

Historical cooling periods are still playing out in the deep Pacific

Cold waters that sank in polar regions hundreds of years ago during the Little Ice Age are still impacting deep Pacific Ocean temperature trends. While the deep Pacific temperature trends are small, they represent a large amount of energy in the Earth system. Photo by: Larry Madin, Woods Hole Oceanographic Institution

The ocean has a long memory. When the water in today's deep Pacific Ocean last saw sunlight, Charlemagne was the Holy Roman Emperor, the Song Dynasty ruled China and Oxford University had just held its very first class. During that time, between the 9th and 12th centuries, the earth's climate was generally warmer before the cold of the Little Ice Age settled in around the 16th century. Now ocean surface temperatures are back on the rise but the question is, do the deepest parts of the ocean know that?

Researchers from the Woods Hole Oceanographic Institution (WHOI) and Harvard University have found that the deep Pacific Ocean lags a few centuries behind in terms of temperature and is still adjusting to the entry into the Little Ice Age. Whereas most of the ocean is responding to modern warming, the deep Pacific may be cooling.

"These waters are so old and haven't been near the surface in so long, they still 'remember' what was going on hundreds of years ago when Europe experienced some of its coldest winters in history," said Jake Gebbie, a physical oceanographer at WHOI and lead author of the study published Jan. 4, 2019, in the journal Science.

"Climate varies across all timescales," adds Peter Huybers, Professor of Earth and Planetary Sciences at Harvard University and co-author of the paper. "Some regional warming and cooling patterns, like the Little Ice Age and the Medieval Warm Period, are well known. Our goal was to develop a model of how the interior properties of the ocean respond to changes in surface climate."

What that model showed was surprising.

"If the surface ocean was generally cooling for the better part of the last millennium, those parts of the ocean most isolated from modern warming may still be cooling," said Gebbie.

The model is, of course, a simplification of the actual ocean. To test the prediction, Gebbie and Huybers compared the cooling trend found in the model to ocean temperature measurements taken by scientists aboard the HMS Challenger in the 1870s and modern observations from the World Ocean Circulation Experiment of the 1990s.

The HMS Challenger, a three-masted wooden sailing ship originally designed as a British warship, was used for the first modern scientific expedition to explore the world's ocean and seafloor. During the expedition from 1872 to 1876, thermometers were lowered into the ocean depths and more than 5,000 temperature measurements were logged.

"We screened this historical data for outliers and considered a variety of corrections associated with pressure effects on the thermometer and stretching of the hemp rope used for lowering thermometers," said Huybers.

The researchers then compared the HMS Challenger data to the modern observations and found warming in most parts of the global ocean, as would be expected due to the warming planet over the 20th Century, but cooling in the deep Pacific at a depth of around two kilometers.

"The close correspondence between the predictions and observed trends gave us confidence that this is a real phenomenon," said Gebbie.

These findings imply that variations in surface climate that predate the onset of modern warming still influence how much the climate is heating up today. Previous estimates of how much heat the Earth had absorbed during the last century assumed an ocean that started out in equilibrium at the beginning of the Industrial Revolution. But Gebbie and Huybers estimate that the deep Pacific cooling trend leads to a downward revision of heat absorbed over the 20th century by about 30 percent.

"Part of the heat needed to bring the ocean into equilibrium with an atmosphere having more greenhouse gases was apparently already present in the deep Pacific," said Huybers. "These findings increase the impetus for understanding the causes of the Medieval Warm Period and Little Ice Age as a way for better understanding modern warming trends."

This research was funded by the James E. and Barbara V. Moltz Fellowship and National Science Foundation grants OCE-1357121 and OCE-1558939.
The Woods Hole Oceanographic Institution is a private, non-profit organization on Cape Cod, Mass., dedicated to marine research, engineering, and higher education. Established in 1930 on a recommendation from the National Academy of Sciences, its primary mission is to understand the oceans and their interaction with the Earth as a whole, and to communicate a basic understanding of the oceans' role in the changing global environment. For more information, please visit www.whoi.edu.

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Researchers from the Woods Hole Oceanographic Institution (WHOI) and Harvard University have found that the deep Pacific Ocean lags a few centuries behind in terms of temperature and is still adjusting to the entry into the Little Ice Age. Whereas most of the ocean is responding to modern warming, the deep Pacific may be cooling.

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Estudio de Corrientes Geomagnéticas inducidas en Suecia

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Estudio de Corrientes Geomagnéticas inducidas en Suecia

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Journal of Advances in Modeling Earth Systems (JAMES)

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Hiding in the Cosmos, Earthquake, Deadly Flood  | S0 News January 7, 2019

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Ocultos en el Cosmos, Terremotos, Inundaciones Mortales

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Ocultos en el Cosmos, Terremotos, Inundaciones Mortales

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Hiding in the Cosmos, Earthquake, Deadly Flood  | S0 News January 7, 2019

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The European Space Agency portal features the latest news in space exploration, human spaceflight, launchers, telecommunications, navigation, monitoring and space science.

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Tormentas Eléctricas como Fuentes de Voltaje

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Tormentas Eléctricas como Fuentes de Voltaje

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Thunderstorm generators operating as voltage sources in global electric circuit models

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The description of global electric circuit (GEC) generators in continuous numerical models is analysed and discussed. It is shown that voltage-source ...

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Thunderstorm generators operating as voltage sources in global electric circuit models

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The description of global electric circuit (GEC) generators in continuous numerical models is analysed and discussed. It is shown that voltage-source ...

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Thunderstorm generators operating as voltage sources in global electric circuit models

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The description of global electric circuit (GEC) generators in continuous numerical models is analysed and discussed. It is shown that voltage-source ...

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Resultados del Experimentos de Materia Obscura Axion

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Resultados del Experimentos de Materia Obscura Axion

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Eyección de Masa Coronal, Tormenta de Nieve Mayor, Remanente de Supernova 

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Eyección de Masa Coronal, Tormenta de Nieve Mayor, Remanente de Supernova 

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Tight CME, Major Blizzard, Proof of Nova Glass | S0 News Jan.8.2018

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HubbleSite: News - Triangulum Galaxy Shows Stunning Face in Detailed Hubble Portrait

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NASA's Hubble Space Telescope has produced this stunningly detailed portrait of the Triangulum galaxy (M33), displaying a full spiral face aglow with the light of nearly 25 million individually resolved stars. It is the largest high-resolution mosaic image of Triangulum ever assembled, composed of 54 Hubble fields of view spanning an area more than 19,000 light-years across.

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Multi-wavelength view of a supernova remnant

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The European Space Agency portal features the latest news in space exploration, human spaceflight, launchers, telecommunications, navigation, monitoring and space science.

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Científico descubre un nuevo Planeta K2-288Bb

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Científico descubre un nuevo Planeta K2-288Bb

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Citizen Scientists Find New World with NASA Telescope

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There are thousands of known exoplanets - planets orbiting stars other than our Sun - but citizen scientists have helped discover one that has a rare quality.

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TESS descubre un 3er nuevo Planeta, HD 21749b

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TESS descubre un 3er nuevo Planeta, HD 21749b

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NASA's Transiting Exoplanet Survey Satellite, TESS, has discovered a third small planet outside our solar system, scientists announced this week at the annual American Astronomical Society meeting in Seattle.

The new planet, named HD 21749b, orbits a bright, nearby dwarf star about 53 light years away, in the constellation Reticulum, and appears to have the longest orbital period of the three planets so far identified by TESS. HD 21749b journeys around its star in a relatively leisurely 36 days, compared to the two other planets - Pi Mensae b, a "super-Earth" with a 6.3-day orbit, and LHS 3844b, a rocky world that speeds around its star in just 11 hours. All three planets were discovered in the first three months of TESS observations.

The surface of the new planet is likely around 300 degrees Fahrenheit - relatively cool, given its proximity to its star, which is almost as bright as the sun.

"It's the coolest small planet that we know of around a star this bright," says Diana Dragomir, a postdoc in MIT's Kavli Institute for Astrophysics and Space Research, who led the new discovery. "We know a lot about atmospheres of hot planets, but because it's very hard to find small planets that orbit farther from their stars, and are therefore cooler, we haven't been able to learn much about these smaller, cooler planets. But here we were lucky, and caught this one, and can now study it in more detail."

The planet is about three times the size of Earth, which puts it in the category of a "sub-Neptune." Surprisingly, it is also a whopping 23 times as massive as the Earth. But it is unlikely that the planet is rocky and therefore habitable; it's more likely made of gas, of a kind that is much more dense than the atmospheres of either Neptune or Uranus.

"We think this planet wouldn't be as gaseous as Neptune or Uranus, which are mostly hydrogen and really puffy," Dragomir says. "The planet likely has a density of water, or a thick atmosphere."

Serendipitously, the researchers have also detected evidence of a second planet, though not yet confirmed, in the same planetary system, with a shorter, 7.8-day orbit. If it is confirmed as a planet, it could be the first Earth-sized planet discovered by TESS.

In addition to presenting their results at the AAS meeting, the researchers have submitted a paper to Astrophysical Journal Letters.
"Something there"
Since it launched in April 2018, TESS, an MIT-led mission, has been monitoring the sky, sector by sector, for momentary dips in the light of about 200,000 nearby stars. Such dips likely represent a planet passing in front of that star.

The satellite trains its four onboard cameras on each sector for 27 days, taking in light from the stars in that particular segment before shifting to view the next one. Over its two-year mission, TESS will survey nearly the entire sky by monitoring and piecing together overlapping slices of the night sky. The satellite will spend the first year surveying the sky in the Southern Hemisphere, before swiveling around to take in the Northern Hemisphere sky.

The mission has released to the public all the data TESS has collected so far from the first three of the 13 sectors that it will monitor in the southern sky. For their new analysis, the researchers looked through this data, collected between July 25 and Oct. 14.

Within the sector 1 data, Dragomir identified a single transit, or dip, in the light from the star HD 21749. As the satellite only collects data from a sector for 27 days, it's difficult to identify planets with orbits longer than that time period; by the time a planet passes around again, the satellite may have shifted to view another slice of the sky.

To complicate matters, the star itself is relatively active, and Dragomir wasn't sure if the single transit she spotted was a result of a passing planet or a blip in stellar activity. So she consulted a second dataset, collected by the High Accuracy Radial velocity Planet Searcher, or HARPS, a high-precision spectrograph installed on a large ground-based telescope in Chile, which identifies exoplanets by their gravitational tug on their host stars.

"They had looked at this star system a decade ago and never announced anything because they weren't sure if they were looking at a planet versus the activity of the star," Dragomir says. "But we had this one transit, and knew something was there."
Stellar detectives
When the researchers looked through the HARPS data, they discovered a repeating signal emanating from HD 21749 every 36 days. From this, they estimated that, if they indeed had seen a transit in the TESS data from sector 1, then another transit should appear 36 days later, in data from sector 3. When that data became publicly available, a momentary glitch created a gap in the data just at the time when Dragomir expected the second transit to occur.

"Because there was an interruption in data around that time, we initially didn't see a second transit, and were pretty disappointed," Dragomir recalls. "But we re-extracted the data and zoomed in to look more carefully, and found what looked like the end of a transit."

She and her colleagues compared the pattern to the first full transit they had originally discovered, and found a near perfect match - an indication that the planet passed again in front of its star, in a 36-day orbit.

"There was quite some detective work involved, and the right people were there at the right time," Dragomir says. "But we were lucky and we caught the signals, and they were really clear."

They also used data from the Planet Finder Spectrograph, an instrument installed on the Magellan Telescope in Chile, to further validate their findings and constrain the planet's mass and orbit.

Once TESS has completed its two-year monitoring of the entire sky, the science team has committed to delivering information on 50 small planets less than four times the size of Earth to the astronomy community for further follow-up, either with ground-based telescopes or the future James Webb Space Telescope.

"We've confirmed three planets so far, and there are so many more that are just waiting for telescope and people time to be confirmed," Dragomir says. "So it's going really well, and TESS is already helping us to learn about the diversity of these small planets."

TESS is a NASA Astrophysics Explorer mission led and operated by MIT in Cambridge, Massachusetts, and managed by Goddard. Additional partners include Northrop Grumman, based in Falls Church, Virginia; NASA's Ames Research Center in California's Silicon Valley; the Harvard-Smithsonian Center for Astrophysics in Cambridge, Massachusetts; MIT Lincoln Laboratory; and the Space Telescope Science Institute in Baltimore. More than a dozen universities, research institutes, and observatories worldwide are participants in the mission.

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TESS discovers its third new planet, with longest orbit yet

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NASA's Transiting Exoplanet Survey Satellite, TESS, has discovered a third small planet outside our solar system, scientists announced this week at the annual American Astronomical Society meeting in Seattle. The new planet, named HD 21749b, orbits a bright, nearby dwarf star about 53 light years away, in the constellation Reticulum, and appears to have the longest orbital period of the three planets so far identified by TESS.

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Tornado, Terremoto, Nieve/Frío récords, Plasma

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Tornado, Terremoto, Nieve/Frío récords, Plasma

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Tornado, Earthquake, Record Snow/Cold, Plasma | S0 News Jan.9.2019

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Descubrieron la NOVA más recurrente, Fríos  Records

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Descubrieron la NOVA más recurrente, Fríos  Records

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Most-Repeating Nova Discovered, Cold Records | S0 News Jan.10.2019

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Planetas jovenes alrededor de Enanas Rojas por Hubble

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Planetas jovenes alrededor de Enanas Rojas por Hubble

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HubbleSite: News - Young Planets Orbiting Red Dwarfs May Lack Ingredients for Life

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Our Sun is not one of the most abundant types of star in our Milky Way galaxy. That award goes to red dwarfs, stars that are smaller and cooler than our Sun. In fact, red dwarfs presumably contain the bulk of our galaxy's planet population, which could number tens of billions of worlds.

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Estudio sobre Materia Negra en la Galaxia de Andrómeda

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Estudio sobre Materia Negra en la Galaxia de Andrómeda

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Estudio sobre Historia & Evolución de Quásares

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Estudio sobre Historia & Evolución de Quásares

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Synopsis: Using data from ALMA, a team of astronomers studied the growth and evolution of bubbles of hot plasma produced by active quasar QuasarAn apparently small (at least to observers on Earth) yet immensely powerful cosmic object. Some quasars (quasi-stellar objects, or QSOs) are strong radio sources. Radio-emitting quasars were the first to be discovered. These are some of the most distant objects in the Universe, and are believed to be fueled by supermassive black holes residing in ancient galaxies. HE 0515-4414. The bubble was analyzed by observing its effect on light from the cosmic microwave background. It is the first time this method has been used to directly study outflows from quasars.
Cosmic microwave background radiation Cosmic Microwave Background RadiationRadiation left over from the Big Bang. Because of the expansion of the Universe, the radiation is detected in the microwave portion of the spectrum (300 MHz [100 cm] to 300 GHz [0.1 cm]), and has a temperature of only 2.7 K (Kelvin) (or -270.45°C). spectrum SpectrumA plot or distribution of light intensity at different frequencies and wavelengths.universe UniverseSimilar to the cosmos, this term that refers to all of space and everything that is contained within it. is the first light in the cosmos. The light we see began its journey when the universe was just 380,000 years old, when the temperature of the universe had finally dropped to the point where the primordial plasma of electrons and protons cooled enough to form transparent hydrogen gas. At first, the cosmic background was a nearly perfect blackbody spectrum. A blackbody spectrum is the of light caused by the temperature of an object. Sunlight, for example, is also a blackbody spectrum. Shortly after it first appeared, the cosmic blackbody was an orange glow, but during its 13.7 billion year journey the expansion of the shifted it to infrared and then microwave radiation. We now see this background as a faint glow of microwave light coming from all directions.

The cosmic background is still a blackbody, but not a perfect one. There are small fluctuations in the background. Regions that are a bit warmer than average, and regions that are slightly cooler. Most of these fluctuations are due to variations in the early universe. Slightly warmer regions expanded to fill the vast voids between galaxies, while slightly cooler regions condensed into galaxies and clusters of galaxies.

But some of these fluctuations are due to the tremendously long journey the light took to reach us. While traveling for billions of years, the light of the cosmic background passed through all the gas, dust and plasma between us and its source. Some of the light was absorbed. Some lost energy by scattering and now appears cooler than it would otherwise. But some of it gained energy, making the cosmic background appear warmer than it should.

This warming process is known as the Sunyaev-Zel'dovich effect (or SZ effect). When low energy photons from the cosmic microwave background pass through a region of hot plasma, they can collide with fast-moving electrons. The photons are then scattered with a great deal of energy. So the cosmic light leaves the region warmer and brighter - leaving a "hole" in the background at low frequencies, corresponding to lower photon energies. By looking for temperature fluctuations in the cosmic background, astronomers can study regions of hot plasma.

In a recent paper published in the Monthly Notices of the Royal Astronomical Society, a team of researchers used the SZ effect to study bubbles of hot plasma near distant quasars. Quasars are bright radio beacons in the sky. They are powered by supermassive black holes in the hearts of galaxies. As the black holes consume matter near them, they radiate tremendous energy. They are often more than 100 times brighter than the galaxy in which they live. This can create a quasar wind of ionized gas that streams away from the galaxy, similar to the way our Sun creates a solar wind. When the quasar wind collides with the diffuse and cool gas of intergalactic space, it can create bubbles of hot plasma.

Quasars aren't as distant as the cosmic microwave background, but they are still billions of light-years Light-yearsThe distance that light travels in one year in a vacuum. One light year is equivalent to about six trillion miles. away. That means any light given off by the plasma bubbles is much too faint to be observed directly. But they can be studied through the SZ effect. In order to do that, however, you need to capture high-resolution images of the microwave background. This is where the Atacama Large Millimeter/submillimeter Array (ALMA) comes in. Located high in the Andes of northern Chile, ALMA can capture microwave images at a resolution similar to visible light images captured by the Hubble space telescope. Just as the Hubble can show us beautiful images of distant nebulae, ALMA can capture images of hot plasma bubbles.

Using data from ALMA, the astronomers detected a bubble near the quasar HE 0515-4414. This is a hyperluminous quasar, meaning that it is extremely bright and active. But surprisingly when they used their data to measure the quasar wind, they found it was smaller than anticipated. The quasar wind is only 0.01% of the total luminosity LuminosityThe amount of energy that a star emits per unit time. It is measured in Watts (Joules/seconds) and is often given in terms relative to our Sun, L⊙ (about 3.846×10^26 W). of the quasar. Theoretical models predicted that the quasar wind should be much stronger. It seems that while quasars can create hot bubbles of plasma around a galaxy, the process isn't particularly efficient.

The scale of the bubble also told them it formed over a period of about 100 million years, and it will take about 600 million years to cool down. Those time scales are long enough that hot plasma bubbles could interact with cooler material in the galaxy to influence star production and the evolution of the galaxy.

Of course this is just the first hot plasma bubble to be observed, and it's impossible to know if HE 0515-4414 is typical or a rare exception. So the search is on to find more bubble-blowing quasars.

Lacy, Mark, et al. " Direct detection of quasar feedback via the Sunyaev-Zeldovich effect." Monthly Notices of the Royal Astronomical Society: Letters 483.1 (2018): L22-L27. ( arxiv version)

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Tale As Old As Time - National Radio Astronomy Observatory

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Using data from ALMA, a team of astronomers studied the growth and evolution of bubbles of hot plasma produced by active quasar HE 0515-4414. The bubble was analyzed by observing its effect on light from the cosmic microwave background. It is the first time this method was used to study quasar dynamics.

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Primera evidencia de remanentes de explosiones de estrellas

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© Credit: Matt Darnley, LJMU
A composite image of Liverpool Telescope data (bottom left) and Hubble Space Telescope data (top right) of the nova super-remnant.M31N 2008-12a is in the centre.

Astrophysicists have found the first ever evidence of gigantic remains being formed from repeated explosions on the surface of a dead star in the Andromeda Galaxy, 2.5 million light years from Earth.

The remains or "super-remnant" measures almost 400 light years across. For comparison, it takes just 8 minutes for light from the Sun to reach us.

A white dwarf is the dead core of a star. When it is paired with a companion star in a binary system, it can potentially produce a nova explosion.

If the conditions are right, the white dwarf can pull gas from its companion star and when enough material builds up on the surface of the white dwarf, it triggers a thermonuclear explosion or "nova", shining a million times brighter than our Sun and initially moving at up to 10,000 km per second.

Astrophysicists including Dr Steven Williams from Lancaster University in the UK examined the nova M31N 2008-12a in the Andromeda Galaxy, one of our nearest neighbours.

They used Hubble Space Telescope imaging, accompanied by spectroscopy from telescopes on Earth, to help uncover the nature of a gigantic super-remnant surrounding the nova. This is the first time such a huge remnant has been associated with a nova, and their research appears in Nature. https://www.nature.com/articles/s41586-018-0825-4

Dr Williams worked on Liverpool Telescope observations of the nova as well as helping to interpret the results.

He said: "This result is significant, as it is the first such remnant that has been found around a nova. This nova also has the most frequent explosions of any we know - once a year. The most frequent in our own Galaxy is only once every 10 years.

"It also has potential links to Type Ia supernovae, as this is how we would expect a nova system to behave when it is nearly massive enough to explode as a supernova."

A Type Ia supernova is caused when the entire white dwarf is blown apart when it reaches a critical upper mass, rather than an explosion on its surface as in the case of the nova in this work. Type Ia supernovae are relatively rare. We have not observed one in our own Galaxy since Kepler's supernova of 1604, named after the famous astronomer Johannes Kepler, who observed it shortly after it exploded and for the following year.

The team simulated how such a nova can create a vast, evacuated cavity around the star, by continually sweeping up the surrounding medium within a shell at the edge of a growing super-remnant.

The models show that the super-remnant - larger than almost all known remnants of supernova explosions - is consistent with being built up by frequent nova eruptions over millions of years.

Dr Matt Darnley from Liverpool John Moores University in the UK, who led the work, said: "Studying M31N 2008-12a and its super-remnant could help us to understand how some white dwarfs grow to their critical upper mass and how they actually explode as a Type Ia Supernova once they get there. Type Ia supernovae are critical tools used to work out how the universe expands and grows."

Back to News

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First evidence of gigantic remains from star explosions

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© Credit: Matt Darnley, LJMU A composite image of Liverpool Telescope data (bottom left) and Hubble Space Telescope data (top right) of the nova super-remnant.M31N 2008-12a is in the centre. Astrophysicists have found the first ever evidence of gigantic remains being formed from repeated explosions on the surface of a dead star in the Andromeda Galaxy, 2.5 million light years from Earth.

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Descubieron Quasar en el Universo temprano

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Descubieron Quasar en el Universo temprano

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Maunakea, Hawaii - Astronomers have discovered the brightest gravitationally lensed object ever seen at a time when the universe was less than one billion years old.

With the help of multiple, world-class telescopes in Hawaii - Gemini Observatory, James Clerk Maxwell Telescope (JCMT), United Kingdom Infra-Red Telescope (UKIRT), and W. M. Keck Observatory on Maunakea, Hawaii Island, as well as the Panoramic Survey Telescope and Rapid Response System (Pan-STARRS1) operated by the University of Hawaii Institute for Astronomy on Haleakala, Maui - the researchers discovered that the brilliant beacon is a quasar, the core of a galaxy with a black hole ravenously eating material surrounding it.

The results are published in today's issue of The Astrophysical Journal Letters and were announced this afternoon during a press conference at the 233 rd Meeting of the American Astronomical Society in Seattle.

Though the quasar is very far away - 12.8 billion light-years - astronomers can detect it because a galaxy closer to Earth acts as a lens and makes the quasar look extra bright. The gravitational field of the closer galaxy warps space itself, bending and amplifying the distant quasar's light. This effect is called gravitational lensing.

Though researchers have searched for these very remote quasars for over 20 years, a rare and fortuitous celestial alignment made this one visible to them.

"We don't expect to find many quasars brighter than that in the whole observable universe," said lead investigator Xiaohui Fan, Regents' Professor of Astronomy at the University of Arizona's Steward Observatory.

The super-bright quasar, cataloged as J043947.08+163415.7, could hold the record of being the brightest lensed quasar in the early universe for some time, making it a unique object for follow-up studies.

Shining at an apparent brightness equivalent to 600 trillion suns, the quasar is fueled by a supermassive black hole at the heart of a young galaxy in the process of forming. An immense amount of energy is emitted as the black hole consumes material around it. The detection provides a rare opportunity to study a zoomed-in image of how such black holes accompanied star formation in the very early universe and influenced the assembly of galaxies.

The quasar existed at a transitional period in the universe's evolution, called reionization, where light from young galaxies and quasars reheated the obscuring hydrogen that cooled off not long after the Big Bang.

The quasar would have gone undetected if not for the power of gravitational lensing, which boosted its brightness by a factor of 50.

However, because very distant quasars are identified by their red color (due to absorption by diffuse gas in intergalactic space), sometimes their light is "contaminated," and looks bluer because of the starlight of an intervening galaxy. As a result, they may be overlooked in quasar searches because their color is diluted to resemble that of a normal galaxy. Fan proposes that many other remote quasars have been missed due to this light contamination.

His team got lucky with finding J043947.08+163415.7, because the quasar is so bright it drowns out the starlight from the especially faint foreground lensing galaxy. "Without this high level of magnification, it would make it impossible for us to see the galaxy," said co-author Feige Wang, a physics postdoctoral scholar at the University of California, Santa Barbara. "We can even look for gas around the black hole and what the black hole may be influencing in the galaxy."

"This detection is a surprising and major discovery; for decades we thought that these lensed quasars in the early universe should be very common, but this is the first of its kind that we have found," said Fabio Pacucci, a postdoctoral associate at Yale University who observed J043947.08+163415.7 with Fan at Keck Observatory. "It gives us a clue on how to search for 'phantom quasars' - sources that are out there, but cannot be really detected yet."
This animation shows an artist's impression of J043947.08+163415.7, a very distant quasar powered by a supermassive black hole. This object is by far the brightest object yet discovered in the early universe. CREDIT: ESA/HUBBLE, NASA, M. KORNMESSER
Pacucci is the lead author of a follow-up paper with Harvard University's Astronomy Department Chair, Abraham (Avi) Loeb, on the theoretical implications of Fan's discovery, which is published in the same issue of The Astrophysical Journal Letters as Fan's paper.

"Our theoretical study predicts that we might be missing a substantial fraction of the population of these 'phantom quasars.' If they are indeed numerous, it would revolutionize our idea of what happened right after the Big Bang, and even change our view of how these cosmic monsters grew up in mass," said Pacucci.

"The puzzling growth of extremely bright quasars within less than a billion years after the Big Bang might be partly a mirage. After removing the magnification by gravitational lensing, the inferred black holes would be less massive and could originate more naturally in the infant universe," added Loeb.
METHODOLOGY
Fan's team selected J043947.08+163415.7 as a very distant quasar candidate based on its color by combining photometric data from the UKIRT Hemisphere Survey in the near-infrared, Pan-STARRS1 survey at optical wavelengths, and NASA's Wide-field Infrared Survey Explorer archive in the mid-infrared.

Follow-up spectroscopic observations at the University of Arizona's Multi-Mirror Telescope confirmed that the candidate was in fact a high-redshift, ultra-distant quasar.

The team then analyzed the quasar in greater detail using Keck Observatory's Low Resolution Imaging Spectrometer (LRIS) to obtain a sensitive spectrum in optical light.

"I have been observing at Keck since I was a graduate student more than 20 years ago," said Fan. "The combination of Keck's large collecting area, powerful instruments, and unparalleled observing conditions on Maunakea allows us to study objects at literally the edge of the observable universe and constantly expand our cosmic horizon."

Another Maunakea Observatory, Gemini North, collected an infrared spectrum, which determined the distance of the quasar and the mass of its powerful black hole.

All the data combined revealed the signature of a very faint foreground galaxy directly between the quasar and Earth that is magnifying the quasar image.

However, the foreground lensing galaxy and the quasar are so close in the sky that it is impossible to separate them with images taken from the ground due to blurring of Earth's atmosphere. It took the exquisitely sharp images by NASA's Hubble Space Telescope to finally reveal that the quasar image is split into three components by a faint lensing galaxy.

"It's a hard system to photograph because it turns out to be so compact, which requires the sharpest view from Hubble," Fan said.

Besides being bright in visible and infrared wavelengths, the lensed quasar is also bright in submillimeter wavelengths, where it was observed with the JCMT. This is due to hot dust heated by intense star formation in the galaxy hosting the lensed quasar. The formation rate is estimated to be up to 10,000 stars per year (by comparison, our Milky Way galaxy makes one star per year).

"Clearly, this black hole is not only accreting gas, but has a lot of star formation around it," said co-author Jinyi Yang, a postdoctoral fellow at the University of Arizona. "However, because of the boosting effect of gravitational lensing, the actual rate of star formation could be much lower than the observed brightness suggests," she added.
This animation depicts how the mass of a galaxy is bending the light of a much more distant quasar through gravitational lensing, making the quasar appear three times larger and 50 times brighter in the night sky. CREDIT: ESA/HUBBLE, L. CALCADA NEXT STEPS
The quasar is ripe for future scrutiny. Fan's team is analyzing a detailed 20-hour spectrum from the European Southern Observatory's Very Large Telescope, which would show gas absorption features to identify chemical composition and temperatures of intergalactic gas in the early universe.

Astronomers also will use the Atacama Large Millimeter/submillimeter Array, and eventually NASA's James Webb Space Telescope, to look within 150 light-years of the black hole to directly detect the influence of the black hole's gravity on gas motion and star formation in its vicinity.
SCIENCE CONTACT:
Xiaohui Fan

Regents' Professor of Astronomy

Steward Observatory

University of Arizona

Email: fan@as.arizona.edu

Phone: (520) 360-0956

ABOUT LRIS

The Low Resolution Imaging Spectrometer (LRIS) is a very versatile visible-wavelength imaging and spectroscopy instrument commissioned in 1993 and operating at the Cassegrain focus of Keck I. Since it has been commissioned it has seen two major upgrades to further enhance its capabilities: addition of a second, blue arm optimized for shorter wavelengths of light; and the installation of detectors that are much more sensitive at the longest (red) wavelengths. Each arm is optimized for the wavelengths it covers. This large range of wavelength coverage, combined with the instrument's high sensitivity, allows the study of everything from comets (which have interesting features in the ultraviolet part of the spectrum), to the blue light from star formation, to the red light of very distant objects. LRIS also records the spectra of up to 50 objects simultaneously, especially useful for studies of clusters of galaxies in the most distant reaches, and earliest times, of the universe. LRIS was used in observing distant supernovae by astronomers who received the Nobel Prize in Physics in2011 for research determining that the universe was speeding up in its expansion.

ABOUT W. M. KECK OBSERVATORY

The W. M. Keck Observatory telescopes are the most scientifically productive on Earth. The two, 10-meter optical/infrared telescopes atop Maunakea on the Island of Hawaii feature a suite of advanced instruments including imagers, multi-object spectrographs, high-resolution spectrographs, integral-field spectrometers, and world-leading laser guide star adaptive optics systems. The data presented herein were obtained at Keck Observatory, which is a private 501(c) 3 non-profit organization operated as a scientific partnership among the California Institute of Technology, the University of California, and the National Aeronautics and Space Administration. The Observatory was made possible by the generous financial support of the W. M. Keck Foundation. The authors recognize and acknowledge the very significant cultural role and reverence that the summit of Maunakea has always had within the Native Hawaiian community. We are most fortunate to have the opportunity to conduct observations from this mountain.

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Astronomers Uncover the Brightest Lensed Quasar in the Early Universe

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Maunakea, Hawaii - Astronomers have discovered the brightest gravitationally lensed object ever seen at a time when the universe was less than one billion years old. With the help of multiple, world-class telescopes in Hawaii - Gemini Observatory, James Clerk Maxwell Telescope (JCMT), United Kingdom Infra-Red Telescope (UKIRT), and W.

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Miles de estrellas convertidas en cristales

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Miles de estrellas convertidas en cristales

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1a evidencia de estrellas enanas blancas cristalizadas

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9 January 2019

AUSTIN, Texas - The first direct evidence of crystallized white dwarf stars has been discovered by an international team of researchers that includes an astronomer at The University of Texas at Austin. Predicted half a century ago, the direct evidence of these stars will be published tomorrow in the journal Nature.

Observations have revealed that these stars have a core of solid carbon and oxygen due to a phase transition during their lifecycle, similar to water turning into ice. This phase transition slows their cooling in multiple ways, making them potentially billions of years older than previously thought.

The discovery, led by Pier-Emmanuel Tremblay of the U.K.'s University of Warwick, is largely based on observations taken with the European Space Agency's Gaia satellite.

Almost all stars end up as white dwarfs, and some of them are among the oldest stars in the universe. They are useful to astronomers because their predictable cooling rate allows them to be used as cosmic clocks to estimate the ages of groups of stars. They are the leftover cores of red giant stars, after these huge stars have died and shed their outer layers. They are then constantly cooling as they release their stored-up heat over billions of years.

The Gaia satellite has enabled the selection of a sample of white dwarfs with precise luminosities and colors that is significantly larger and more complete than any previous survey. For the study, the team selected 15,000 white dwarfs within about 300 light-years of Earth.

White dwarfs get fainter and redder as they cool, which leads to a predictable distribution of white dwarfs in a plot of brightness versus color. The astronomers identified a pile-up in this plot, an excess in the number of stars at specific colors and luminosities. When compared with evolutionary models of white dwarfs, the pile-up strongly coincides with the phase in their development in which latent heat is predicted to be released in large amounts, resulting in a slowdown of their cooling process. It is estimated that in some cases these stars have slowed their aging by as much as 2 billion years.

Bart Dunlap, a postdoctoral fellow with UT Austin's Wootton Center for Astrophysical Plasma Properties, working with JJ Hermes, made the discovery independently of the Warwick team and later joined forces with Tremblay. Hermes, a former UT graduate student, is now an assistant professor at Boston University.

"More than 50 years ago, Hugh Van Horn, an astronomer at the University of Rochester, predicted that we should see a crystallization sequence because of a slowdown in cooling when white dwarfs crystallize, but at the time, the data weren't good enough to check this prediction," Dunlap said. "Gaia finally made it possible to see what he predicted, and it really pops out in the data."

Just as liquid water releases extra energy when it changes into ice - this energy is known as latent heat - the dense plasmas in the interiors of white dwarfs were predicted to release enough energy to noticeably slow their trek toward cool, faint stellar embers.

"All white dwarfs will crystallize at some point in their evolution, although more massive white dwarfs go through the process sooner," said Tremblay, who led the study. "This means that billions of white dwarfs in our galaxy have already completed the process and are essentially metallic crystal spheres in the sky."

This includes our own sun, which will become a crystal white dwarf in about 10 billion years.

Crystallization is the process of a material becoming a solid state in which its atoms form an ordered structure. Under the extreme pressures in white dwarf cores, atoms are packed so densely that their electrons become unbound, leaving a conducting electron gas governed by quantum physics, and positively charged nuclei in a fluid form. When the core cools to about 10 million degrees, the dense carbon oxygen plasma is cool enough that the fluid begins to solidify, forming a crystalline core at its heart.

"These results are really telling us a lot about the amount of pent-up energy these stars can release while cooling off," Dunlap said.

The astronomers say they should have access to even better data from Gaia by 2021.

- END -
Media Contact:
Rebecca Johnson, Communications Mgr.
UT Austin McDonald Observatory
512-475-6763

Dr. Bart Dunlap, Postdoctoral Fellow
UT Austin Wootton Center for Astrophysical Plasma Properties & McDonald Observatory
501-940-2110

Dr. JJ Hermes, Assistant Professor of Astronomy
Boston University
512-517-2442

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Thousands of Stars Observed Turning into Crystals for the First Time

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9 January 2019 AUSTIN, Texas - The first direct evidence of crystallized white dwarf stars has been discovered by an international team of researchers that includes an astronomer at The University of Texas at Austin. Predicted half a century ago, the direct evidence of these stars will be published tomorrow in the journal Nature.

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Que destruye una estrella en una galaxia distante

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Chandra :: Photo Album :: ASASSN-14li :: January 9, 2019

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This debris from the shredded star gave astronomers an avenue to get a direct measure of the black hole's spin in ASASSN-14li. They found that the event horizon around this black hole is about 300 times the diameter of the Earth, yet rotates once every two minutes (compared to the 24 hours it takes to complete one rotation).

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Flujo de un Hoyo Negro descubierto por Chandra 

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Flujo de un Hoyo Negro descubierto por Chandra 

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Galaxia CygnusA

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Chandra :: Photo Album :: Cygnus A :: January 9, 2019

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The hole is visible because the path of the rebounding jet between hotspots E and D is almost directly along the line of sight to Earth, as shown by the schematic figure depicting the view of Cygnus A from above.

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Centro de Clima Espacial - Ionosfera , Alemania (SWACI)

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Centro de Clima Espacial - Ionosfera , Alemania (SWACI)

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Centro de Clima Espacial - Ionosfera , Alemania (SWACI)

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Centro de Clima Espacial - Ionosfera , Alemania (SWACI)

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Aceleración de la Inversión de los Polos Magnéticos, Noticias destacadas

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Aceleración de la Inversión de los Polos Magnéticos, Noticias destacadas

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Magnetic Pole Reversal Acceleration, Top News | S0 News Jan.11.2019

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2) Llamaradas al mínimo (A)
3) Hoyo Coronal #66 al SUR (-2), en posición. Perturbaciones en un par de días a lo mas.

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*Rusia, Grecia, e Israel

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Energía del Espacio | El corrimiento ha empezado

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Energía del Espacio | El corrimiento ha empezado