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scienceetfiction · 5 years

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2018 in Science

from Wikipedia

Some highlights:

1 January – Researchers at Harvard, writing in Nature Nanotechnology, report the first single lens that can focus all colours of the rainbow in the same spot and in high resolution, previously only achievable with multiple lenses.

2 January – Physicists at Cornell University report the creation of "muscle" for shape-changing, cell-sized robots.

3 January – Scientists in Rome unveil the first bionic hand with a sense of touch that can be worn outside a laboratory.

9 January – A pattern in exoplanets is discovered by a team of multinational researchers led by the Université de Montréal: Planets orbiting the same star tend to have similar sizes and regular spacings. This could imply that most planetary systems form differently from the Solar System.

10 January – Researchers at Imperial College London and King's College London publish a paper in the journal Scientific Reports about the development of a new 3D bioprinting technique, which allows the more accurate printing of soft tissue organs, such as lungs. 15 January – University of Washington scientists publish a report in the journal Nature Chemistry of the development of a new form of biomaterial based delivery system for therapeutic drugs, which only release their cargo under certain physiological conditions, thereby potentially reducing drug side-effects in patients.

17 January – Engineers at the University of Texas at Austin, in collaboration with Peking University scientists, announce the creation of a memory storage device only one atomic layer thick; a so-called 'atomristor'.

19 January – Researchers at the Technical University of Munich report a new propulsion method for molecular machines, which enables them to move 100,000 times faster than biochemical processes used to date.

22 January – Engineers at MIT develop a new computer chip, with "artificial synapses," which process information more like neurons in a brain.

24 January – Scientists in China report in the journal Cell the creation of two monkey clones, named Zhong Zhong and Hua Hua, using the complex DNA transfer method that produced Dolly the sheep, for the first time.

25 January – Researchers report evidence that modern humans migrated from Africa at least as early as 194,000 years ago, somewhat consistent with recent genetic studies, and much earlier than previously thought.

Scientists working for Calico, a company owned by Alphabet, publish a paper in the journal eLife which presents possible evidence that Heterocephalus glaber (naked mole-rat) do not face increased mortality risk due to aging.

29 January – Scientists report, for the first time, that 800 million viruses, mainly of marine origin, are deposited daily from the Earth's atmosphere onto every square meter of the planet's surface, as the result of a global atmospheric stream of viruses, circulating above the weather system, but below the altitude of usual airline travel, distributing viruses around the planet.

6 February – The National Snow and Ice Data Center (NSIDC) reports that global sea ice extent has fallen to a new record low. 9 February – Human eggs are grown in the laboratory for the first time, by researchers at the University of Edinburgh.

14 February – Researchers found that blocking the enzyme beta-secretase (BACE1) in mice reduces formation of plaques responsible for Alzheimer's disease.

16 February – Scientists report, for the first time, the discovery of a new form of light, which may involve polaritons, that could be useful in the development of quantum computers.

19 February – Scientists identify traces of the genes of the indigenous Taíno people in modern-day Puerto Ricans, indicating that the ethnic group was not extinct as previously believed.

28 February – Astronomers report, for the first time, a signal of the reionization epoch, an indirect detection of light from the earliest stars formed – about 180 million years after the Big Bang.

9 March – NASA medical researchers report that human spaceflight may alter gene expression in astronauts, based on twin studies where one astronaut twin, Scott Kelly, spent nearly one year in space while the other, Mark Kelly, remained on Earth.

19 March – Uber suspends all of its self-driving cars worldwide after a woman is killed by one of the vehicles in Arizona. This is the first recorded fatality using a fully automated version of the technology.

18 April – Nanyang Technological University demonstrates a robot that can autonomously assemble an IKEA chair without interruption.

25 April – Scientists publish evidence that asteroids may have been primarily responsible for bringing water to Earth.

27 April – Stephen Hawking's final paper – A smooth exit from eternal inflation? – is published in the Journal of High Energy Physics.

30 April – Researchers report identifying 6,331 groups of genes that are common to all living animals, and which may have arisen from a single common ancestor that lived 650 million years ago in the Precambrian.

10 May – NASA's Carbon Monitoring System (CMS) is cancelled by the Trump administration.

17 May – Scientists warn that banned CFC-11 gas emissions are originating from an unknown source somewhere in East Asia, with potential to damage the ozone layer.

22 May – Scientists from Purdue University and the Chinese Academy of Sciences report the use of CRISPR/Cas9 to develop a variety of rice producing 25-31% more grain than traditional breeding methods.

24 May – Researchers at the University of Leeds report that climate change could increase arable land in boreal regions by 44% by the year 2100, while having a negative impact everywhere else.

30 May – The first 3D printed human corneas are created at Newcastle University. The FDA approves the first artificial iris.

Physicists of the MiniBooNE experiment report a stronger neutrino oscillation signal than expected, a possible hint of sterile neutrinos, an elusive particle that may pass through matter without any interaction whatsoever.

4 June – Direct coupling of the Higgs boson with the top quark is observed for the first time by the ATLAS experiment and the CMS experiment at CERN.

6 June – Footprints in the Yangtze Gorges area of South China, dating back 546 million years, are reported to be the earliest known record of an animal with legs.

8 June – The U.S. Department of Energy’s Oak Ridge National Laboratory unveils Summit as the world’s most powerful supercomputer, with a peak performance of 200,000 trillion calculations per second, or 200 petaflops.

20 June – Gene-edited pigs are made resistant to porcine reproductive and respiratory syndrome, one of the world's most costly animal diseases.

2 July – First confirmed image of a newborn planet, exoplanet PDS 70b, several times larger than the planet Jupiter.

11 July – Scientists report the discovery in China of the oldest stone tools outside of Africa, estimated at 2.12 million years old.

12 July – The IceCube Neutrino Observatory announces that they have traced a neutrino that hit their Antarctica-based research station in September 2017 back to its point of origin in a blazar 3.7 billion light-years away. This is the first time that a neutrino detector has been used to locate an object in space.

Using NASA's Hubble and ESA's Gaia, astronomers make the most precise measurements to date of the universe's expansion rate – a figure of 73.5 km (45.6 miles) per second per megaparsec – reducing the uncertainty to just 2.2 percent.

17 July – Scientists led by Scott S. Sheppard report the discovery of 12 new moons of Jupiter, taking its total number to 79. This includes an "oddball", Valetudo (originally known as S/2016 J 2; Roman-numeral designation Jupiter LXII), that is predicted to eventually collide with a neighbouring moon.

20 July – Scientists at the University of Alabama at Birmingham announce the reversal of aging-associated skin wrinkles and hair loss in a mouse model. 25 July – Scientists report the discovery, based on MARSIS radar studies, of a subglacial lake on Mars, 1.5 km (0.93 mi) below the southern polar ice cap (see image), and extending sideways about 20 km (12 mi), the first known stable body of water on the planet.

27 July – The longest total lunar eclipse of the 21st century occurs.

30 July – Using high-resolution satellite images, researchers from the Chizé Centre for Biological Studies report an 88% reduction in the world's biggest colony of king penguins, found on Île aux Cochons in the subantarctic Crozet Archipelago.

A study by NASA's Goddard Space Flight Center concludes that terraforming of Mars is physically impossible with present-day technology.

1 August – Lab-grown lungs are successfully transplanted into pigs for the first time.

16 August – Scientists at Sandia National Laboratories reveal a platinum-gold alloy believed to be the most wear-resistant metal in the world, 100 times more durable than high-strength steel.

16 August – First complete map of the wheat genome.

18 August – Research presented at the Goldschmidt conference in Boston concludes that water is likely to be a common feature of exoplanets between two and four times the size of Earth, with implications for the search of life in our Galaxy.

20 August – Scientists report that life, based on genetic and fossil evidences, may have begun on Earth nearly 4.5 billion years ago, much earlier than thought before.

22 August – Scientists report evidence of a 13 year-old hominin female, nicknamed Denny, estimated to have lived 90,000 years ago, and who was determined to be half Neanderthal and half Denisovan, based on genetic analysis of a bone fragment discovered in Denisova Cave; the first time an ancient individual was discovered whose parents belonged to distinct human groups.

Researchers report evidence of rapid shifts (in geological-time terms), nearly 30 times faster than known previously, of geomagnetic reversals, where the north magnetic pole of Earth becomes the south magnetic pole and vice versa, including a chronozone that lasted only 200 years, much shorter than any other such reversal found earlier.

30 August – Researchers from the Chinese University of Hong Kong report a new way of controlling nanobots, using swarm behaviours to do complex tasks in minimally invasive surgeries.

6 September – A study by the University of Illinois at Urbana-Champaign finds that large-scale solar panels and wind turbines in the Sahara desert would have a major impact on rainfall, vegetation and temperatures – potentially greening the region.

12 September – Scientists report the discovery of the earliest known drawing by Homo sapiens, which is estimated to be 73,000 years old, much earlier than the 43,000 years old artifacts understood to be the earliest known modern human drawings found previously.

20 September – Scientists discover molecules of fat in an ancient fossil to reveal the earliest confirmed animal in the geological record that lived on Earth 558 million years ago.

A paper in the Cryosphere journal, from the European Geosciences Union, suggests that building walls on the seafloor could halt the slide of undersea glaciers, which are melting due to warmer ocean temperatures.

Using data from the European Space Agency’s X-ray observatory XMM-Newton, astronomers report the first detection of matter falling into a black hole at 30% of the speed of light, located in the centre of the billion-light year distant galaxy PG211+143.

25 September – Scientists determine that Vorombe titan, an extinct elephant bird from the island of Madagascar which reached weights of 800 kg (1,800 lb) and heights of 3 m (9.8 ft) tall, is the largest bird known to have existed.

26 September – Researchers provide evidence that phosphorus compounds, key components for life, are made in interstellar space and distributed throughout outer space, including the early Earth.

27 September – A study in the journal Science concludes that polychlorinated biphenyls (PCBs) could halve killer whale populations in the most heavily contaminated areas within 30–50 years. 1 October – NASA-funded researchers find that lengthy journeys into outer space, including travel to the planet Mars, may substantially damage the gastrointestinal tissues of astronauts. The studies support earlier work that found such journeys could significantly damage the brains of astronauts, and age them prematurely. However, unlike the conditions in space, the study admitted the full radiation doses over short periods.

Astronomers announce the discovery of 2015 TG387 (also known as "The Goblin"), a trans-Neptunian object and sednoid in the outermost part of the Solar System, which may help explain some apparent effects of a hypothetical planet named Planet Nine (or Planet X).

11 October – Physicists report that quantum behavior can be explained with classical physics for a single particle, but not for multiple particles as in quantum entanglement and related nonlocality phenomena ("spooky action at a distance" ["gruselige Action in einiger Entfernung" (german)], according to Albert Einstein).

Harvard astronomers present an analytical model that suggests matter—and potentially dormant spores—can be exchanged across the vast distances between galaxies, a process termed 'galactic panspermia', and not be restricted to the limited scale of solar systems.

The world's fastest camera, able to capture 10 trillion frames per second, is announced by the Institut national de la recherche scientifique (INRS) in Quebec, Canada.

15 October – A study by the Rensselaer Polytechnic Institute finds that insect populations in Puerto Rico have crashed since the 1970s, with some species witnessing a 60-fold decrease in numbers. The fall is attributed to a 2.0 °C rise in tropical forest temperatures.

16 October – A comprehensive analysis of demographic trends published in The Lancet predicts that all countries are likely to experience at least a slight increase in life expectancy by 2040. Spain is expected to overtake Japan as it rises from fourth to first place, with an average lifespan of 85.8 years.

Astronomers report that GRB 150101B, a gamma-ray burst event detected in 2015, may be directly related to the historic GW170817, a gravitational wave event detected in 2017, and associated with the merger of two neutron stars. The similarities between the two events, in terms of gamma ray, optical and x-ray emissions, as well as to the nature of the associated host galaxies, are "striking", suggesting the two separate events may both be the result of the merger of neutron stars, and both may be a kilonova (i.e., a luminous flash of radioactive light that produces elements like silver, gold, platinum and uranium), which may be more common in the universe than previously understood, according to the researchers.

17 October – Researchers report possible transgenerational epigenetic inheritance (i.e., transmission of information from one generation of an organism to the next that affects the traits of offspring without alteration of the primary structure of DNA) in the form of paternal transmission of epigenetic memory via of sperm chromosomes in the roundworm Caenorhabditis elegans, a laboratory test organism.

24 October – Scientists report discovering the oldest weapons found in North America, ancient spear points, dated to 13,500 – 15,500 years ago, made of chert, predating the clovis culture (typically dated to 13,000 years ago), in the state of Texas.

1 November – The Earth BioGenome Project is launched, a 10-year global effort to sequence the genomes of all 1.5 million known animal, plant, protozoan and fungal species on Earth. Astronomers from Harvard University suggest that the interstellar object 'Oumuamua may be an extraterrestrial solar sail from an alien civilization, in an effort to help explain the object's "peculiar acceleration".

2 November – The world’s largest neuromorphic supercomputer, the million-core 'SpiNNaker' machine, is switched on by the University of Manchester, England.

5 November – Polar ozone holes are healing faster than previously thought, and are expected to completely heal by 2060.

5 November – Astronomers report the discovery of one of the oldest stars, named 2MASS J18082002-5104378 B, in the universe, about 13.5 billion-years-old, possibly one of the very first stars, a tiny ultra metal-poor (UMP) star made almost entirely of materials released from the Big Bang. The discovery of the star in the Milky Way galaxy suggests that the galaxy may be at least 3 billion years older than thought earlier.

Scientists report the discovery of the smallest known ape, Simiolus minutus, which weighed approximately eight pounds, and lived about 12.5 million years ago in Kenya in East Africa.

7 November – Scientists report the discovery of the oldest known figurative art painting, over 40,000 (perhaps as old as 52,000) years old, of an unknown animal, in the cave of Lubang Jeriji Saléh on the Indonesian island of Borneo

12 November – China's Institute of Plasma Physics announces that plasma in the Experimental Advanced Superconducting Tokamak (EAST) has reached 100 million degrees Celsius.

Researchers at Japan's National Institute of Advanced Industrial Science and Technology (AIST) reveal a humanoid robot prototype, HRP-5P, intended to autonomously perform heavy labor or work in hazardous environments.

20 November – The World Meteorological Organization (WMO) publishes its latest Greenhouse Gas Bulletin, showing record high concentrations of heat-trapping greenhouse gases, with levels of carbon dioxide (CO2) reaching 405.5 parts per million (ppm) in 2017, up from 403.3 ppm in 2016 and 400.1 ppm in 2015. The WMO reports that "there is no sign of a reversal in this trend, which is driving long-term climate change, sea level rise, ocean acidification and more extreme weather."

22 November – Research published in Environmental Research Letters concludes that stratospheric aerosol injection to curb global warming is "technically possible" and would be "remarkably inexpensive" at $2 to 2.5 billion per year over the first 15 years.

23 November – The Brazilian government reports that deforestation in the Amazon rainforest has reached its highest rate for a decade, with 7,900 sq km (3,050 sq miles) destroyed between August 2017 and July 2018, largely due to illegal logging.

24 November – Scientists report that nearly all extant populations of animals, including humans, may be a result of a population expansion that began between one and two hundred thousand years ago, based on genetic mitochondrial DNA studies.

25 November – Chinese scientists report the birth of twin human girls, Lulu and Nana, as the world's first genetically edited babies. The human genes were edited to resist the HIV virus.

27 November – Researchers at the University of Southern California publish details of a freeze-dried polio vaccine that does not require refrigeration.

30 November – Astronomers report that the extragalactic background light (EBL), the total amount of light that has ever been released by all the stars in the observable universe, amounts to 4 × 1084 photons.

10 December – Voyager 2, a space probe launched in 1977, is confirmed (image of onboard detections) to have left the Solar System for interstellar space on 5 November 2018, six years after its sister probe, Voyager 1.

Four glaciers in the Vincennes Bay region of Antarctica are found to be thinning at surprisingly fast rates, casting doubt on the idea that the eastern part of the icy continent is stable.

Researchers announce the discovery of considerable amounts of life forms, including 70% of bacteria and archea on Earth, comprising up to 23 billion tonnes of carbon, living up to at least 4.8 km (3.0 mi) deep underground, including 2.5 km (1.6 mi) below the seabed, according to a ten-year Deep Carbon Observatory project.

11 December – A report on the impact of climate change in the Arctic, published during the latest American Geophysical Union meeting, concludes that populations of wild reindeer, or caribou, have crashed from almost 5 million to just 2.1 million animals in the last two decades.

17 December – Astronomers led by Scott Sheppard announce the discovery of 2018 VG18, nicknamed "Farout", the most distant body ever observed in the Solar System at approximately 120 AU.

Scientists announce that the earliest feathers may have originated 250 million years ago, 70 million years earlier than previously thought

18 December – Scientists report that the earliest flowers began about 180 million years ago, 50 million years earlier than previously thought.

and more

#science #2018 #technology #astronomy #physics #biology

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nasa · 6 years

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Pick Your Favorite Findings From Fermi’s First Decade

The Fermi Gamma-ray Space Telescope has been observing some of the most extreme objects and events in the universe — from supermassive black holes to merging neutron stars and thunderstorms — for 10 years. Fermi studies the cosmos using gamma rays, the highest-energy form of light, and has discovered thousands of new phenomena for scientists.

Here are a few of our favorite Fermi discoveries, pick your favorite in the first round of our “Fermi Science Playoff.”

Colliding Neutron Stars

In 2017, Fermi detected a gamma ray burst at nearly the same moment ground observatories detected gravitational waves from two merging neutron stars. This was the first time light and ripples in space-time were detected from the same source.

The Sun and Moon in Gamma Rays

In 2016, Fermi showed the Moon is brighter in gamma rays than the Sun. Because the Moon doesn’t have a magnetic field, the surface is constantly pelted from all directions by cosmic rays. These produce gamma rays when they run into other particles, causing a full-Moon gamma-ray glow.

Record Rare from a Blazar

The supermassive black hole at the center of the galaxy 3C 279 weighs a billion times the mass of our Sun. In June 2015, this blazar became the brightest gamma-ray source in the sky due to a record-setting flare.

The First Gamma-Ray Pulsar in Another Galaxy

In 2015, for the first time, Fermi discovered a gamma-ray pulsar, a kind of rapidly spinning superdense star, in a galaxy outside our own. The object, located on the outskirts of the Tarantula Nebula, also set the record for the most luminous gamma-ray pulsar we’ve seen so far.

A Gamma-Ray Cycle in Another Galaxy

Many galaxies, including our own, have black holes at their centers. In active galaxies, dust and gas fall into and “feed” the black hole, releasing light and heat. In 2015 for the first time, scientists using Fermi data found hints that a galaxy called PG 1553+113 has a years-long gamma-ray emission cycle. They’re not sure what causes this cycle, but one exciting possibility is that the galaxy has a second supermassive black hole that causes periodic changes in what the first is eating.

Gamma Rays from Novae

A nova is a fairly common, short-lived kind of explosion on the surface of a white dwarf, a type of compact star not much larger than Earth. In 2014, Fermi observed several novae and found that they almost always produce gamma-rays, giving scientists a new type of source to explore further with the telescope.

A Record-Setting Cosmic Blast

Gamma-ray bursts are the most luminous explosions in the universe. In 2013, Fermi spotted the brightest burst it’s seen so far in the constellation Leo. In the first three seconds alone, the burst, called GRB 130427A, was brighter than any other burst seen before it. This record has yet to be shattered.

Cosmic Rays from Supernova Leftovers

Cosmic rays are particles that travel across the cosmos at nearly the speed of light. They are hard to track back to their source because they veer off course every time they encounter a magnetic field. In 2013, Fermi showed that these particles reach their incredible speed in the shockwaves of supernova remains — a theory proposed in 1949 by the satellite’s namesake, the Italian-American physicist Enrico Fermi.

Discovery of a Transformer Pulsar

In 2013, the pulsar in a binary star system called AY Sextanis switched from radio emissions to high-energy gamma rays. Scientists think the change reflects erratic interaction between the two stars in the binary.

Gamma-Ray Measurement of a Gravitational Lens

A gravitational lens is a kind of natural cosmic telescope that occurs when a massive object in space bends and amplifies light from another, more distant object. In 2012, Fermi used gamma rays to observe a spiral galaxy 4.03 billion light-years away bending light coming from a source 4.35 billion light-years away.

New Limits on Dark Matter

We can directly observe only 20 percent of the matter in the universe. The rest is invisible to telescopes and is called dark matter — and we’re not quite sure what it is. In 2012, Fermi helped place new limits on the properties of dark matter, essentially narrowing the field of possible particles that can describe what dark matter is.

‘Superflares’ in the Crab Nebula

The Crab Nebula supernova remnant is one of the most-studied targets in the sky — we’ve been looking at it for almost a thousand years! In 2011, Fermi saw it erupt in a flare five times more powerful than any previously seen from the object. Scientists calculate the electrons in this eruption are 100 times more energetic than what we can achieve with particle accelerators on Earth.

Thunderstorms Hurling Antimatter into Space

Terrestrial gamma-ray flashes are created by thunderstorms. In 2011, Fermi scientists announced the satellite had detected beams of antimatter above thunderstorms, which they think are a byproduct of gamma-ray flashes.

Giant Gamma-Ray Bubbles in the Milky Way

Using data from Fermi in 2010, scientists discovered a pair of “bubbles” emerging from above and below the Milky Way. These enormous bubbles are half the length of the Milky Way and were probably created by our galaxy’s supermassive black hole only a few million years ago.

Hint of Starquakes in a Magnetar

Neutron stars have magnetic fields trillions of times stronger than Earth’s. Magnetars are neutron stars with magnetic fields 1,000 times stronger still. In 2009, Fermi saw a storm of gamma-ray bursts from a magnetar called SGR J1550-5418, which scientists think were related to seismic waves rippling across its surface.

A Dark Pulsar

We observe many pulsars using radio waves, visible light or X-rays. In 2008, Fermi found the first gamma-ray only pulsar in a supernova remnant called CTA 1. We think that the “beam” of gamma rays we see from CTA 1 is much wider than the beam of other types of light from that pulsar. Those other beams never sweep across our vision — only the gamma-rays.

Have a favorite Fermi discovery or want to learn more? Cast your vote in the first of four rounds of the Fermi Science Playoff to help rank Fermi’s findings. Or follow along as we celebrate the mission all year.

Make sure to follow us on Tumblr for your regular dose of space: http://nasa.tumblr.com.

#nasa #space #fermi #discoveries #science #universe #black hole #star #explosion #supernova #pulsar #light #beam #gamma ray #telescope

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theincrediblescience-blog · 7 years

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Cosmic lens lets astronomers zoom in on a black hole’s burps

Space experts have gotten their best take a gander at blobs of hot gas escaping a supermassive dark gap, on account of another sort of infinite amplifying glass.

Anthony Readhead of the Owens Valley Radio Observatory at Caltech and partners got two little, hot blasts voyaging far from a brilliant system called J1415+1320 at close to the speed of light. Despite the fact that the cosmic system is billions of light-years away and the blobs are modest contrasted and the universe, it gives the idea that a fortunate arrangement of stars may have made what's known as a gravitational focal point, amplifying the world and its environs.

"We're peering directly down into the center of the core of this dynamic cosmic system," Readhead says. "We think this is possibly an effective new window." The scientists report their discoveries August 20 of every two papers in the Astrophysical Journal.

J1415+1320 is what's known as a blazar, a splendid cosmic system with a voracious supermassive dark gap at its inside (SN: 3/4/17, p. 13). The dark gap is effectively sustaining on a plate of white-hot gas that twirls around it, influencing the host world to sparkle brilliantly in gamma and radio waves. The universe is among around 1,800 blazars that Readhead and his group have watched twice per week since 2008. "No one has taken a gander at the sky very like that earlier," he says.

Beginning in 2009, J1415+1320 began accomplishing something greatly interesting. Through the span of about a year, the blazar developed brighter, at that point dimmer, at that point brighter once more. Plotting its brilliance after some time uncovered a symmetrical U shape in the information.

At to start with, the group thought the change was caused by a billow of plasma inside the Milky Way that happened to go amongst Earth and the blazar, disseminating its light. Be that as it may, at that point a similar thing happened again in 2014.

Discussions with partners at different observatories uncovered that the system acted a similar way when seen in numerous electromagnetic wavelengths, not simply with a radio telescope. That wouldn't occur if a stray billow of plasma were at fault.

Presently, Readhead and his associates contend that they're seeing the blazar's dark opening emanate little burps of plasma, amplified many circumstances by another sort of gravitational focal point. These infinite focal points are monstrous items that can twist the way of light going by them, influencing wellsprings of light out of sight to look misshaped from the perspective of telescopes on Earth. Cosmologists can utilize this mutilation to find out about the foundation objects and their focal points.

Up until now, all known focal points have either been colossal — a large number of times the mass of the sun, similar to a whole world — or moderately minor, similar to a solitary planet.

The focal point that amplified J1415+1320 is by all accounts something in the middle of, from 1,000 to 1 million times the mass of the sun. It is around 2.7 billion light-years away, and is related with a winding cosmic system, yet is less monstrous than the whole universe. The focal point could exist in or adjacent the universe, and could be a gathering of thousands of stars like a globular group. Or, then again it could be something more intriguing, as hard to-spot average size dark gaps.

The U-molded components in the information showed up when the dark gap radiated clusters of issue that dashed away at close to the speed of light, and go behind this focal point from the viewpoint of Earth, the group says.

"This was a to a great degree intriguing, interesting perception," says astrophysicist Eileen Meyer of the University of Maryland, Baltimore County. "To the extent I know, there's not at all like that that has been seen some time recently."

Readhead's group still needs to mention more objective facts to affirm that the focal point is genuine. Yet, in the event that it will be, it could help illuminate an extraordinary puzzle about dark openings: how they shoot planes of hot charged particles into space. Numerous dynamic cosmic systems show these splendid planes, however their starting points are baffling.

"We really don't know how these planes are propelled," says Harish Vedantham, additionally of Owens Valley Radio Observatory and a coauthor of the new papers. "We don't have authoritative answers since we can't make a picture on the [size] sizes of where this discharge is occurring."

The new perceptions of J1415+1320 are not exactly such a picture. Be that as it may, they propose an approach to some time or another create one. The focal point amplified the dark gap 100 times more than is conceivable with current telescopes, so more perceptions could help uncover more about its tendency.

"This resembles a venturing stone," Vedantham says. "This is a conceivable method to go in and get this high-determination perspective of how a dark gap is propelling these planes."

On the off chance that further perceptions discount the focal point, at that point things could get much more odd. "On the off chance that it's not a gravitational focal point, at that point it's an inherent property of the planes themselves," Readhead says. "At that point it will have intriguing ramifications for the material science of the genuine stream. I believe it's a win-win circumstance."

#cosmic lens

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arxt1 · 5 years

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X-ray properties of z>4 blazars. (arXiv:1908.08084v1 [astro-ph.GA])

We present the X-ray analysis of the largest flux-limited complete sample of blazar candidates at z>4 selected from the Cosmic Lens All Sky Survey (CLASS). After obtaining a nearly complete (24/25) X-ray coverage of the sample (from Swift-XRT, XMM-Newton and Chandra), we analysed the spectra in order to identify the bona-fide blazars. We classified the sources based on the shape of their Spectral Energy Distributions (SEDs) and, in particular, on the flatness of the X-ray emission and its intensity compared to the optical one. We then compared these high-z blazars with a blazar sample selected at lower redshifts (z~1). We found a significant difference in the X-ray-to-radio luminosity ratios, with the CLASS blazars having a mean ratio 2.4+/-0.5 times larger than low-z blazars. We tentatively interpret this evolution as due to the interaction of the electrons of the jet with the Cosmic Microwave Background (CMB) photons, which is expected to boost the observed X-ray emission at high redshifts. Such a dependence has been already observed in highly radio-loud AGNs in the recent literature. This is the first time it is observed using a statistically complete radio flux limited sample of blazars. We have then evaluated whether this effect could explain the differences in the cosmological evolution recently found between radio and X-ray selected samples of blazars. We found that the simple version of this model is not able to solve the tension between the two evolutionary results.

from astro-ph.HE updates on arXiv.org https://ift.tt/33Wvqh9

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theincrediblescience-blog · 7 years

Text

Cosmic lens lets astronomers zoom in on a black hole’s burps

Seeing into the core of a faraway cosmic system could clarify how planes of hot material get their begin

Cosmologists have gotten their best take a gander at blobs of hot gas escaping a supermassive dark opening, because of another sort of enormous amplifying glass.

Anthony Readhead of the Owens Valley Radio Observatory at Caltech and associates got two little, hot blasts voyaging far from a brilliant cosmic system called J1415+1320 at close to the speed of light. In spite of the fact that the world is billions of light-years away and the blobs are little contrasted and the universe, it gives the idea that a fortunate arrangement of stars may have made what's known as a gravitational focal point, amplifying the system and its environs.

"We're peering directly down into the center of the core of this dynamic cosmic system," Readhead says. "We think this is possibly an effective new window." The specialists report their discoveries August 20 out of two papers in the Astrophysical Journal.

J1415+1320 is what's known as a blazar, a splendid universe with a ravenous supermassive dark gap at its middle (SN: 3/4/17, p. 13). The dark opening is effectively encouraging on a plate of white-hot gas that twirls around it, making the host system sparkle brilliantly in gamma and radio waves. The cosmic system is among around 1,800 blazars that Readhead and his group have watched twice every week since 2008. "No one has taken a gander at the sky very like that earlier," he says.

Beginning in 2009, J1415+1320 began accomplishing something to a great degree abnormal. Through the span of about a year, the blazar developed brighter, at that point dimmer, at that point brighter once more. Plotting its splendor after some time uncovered a symmetrical U shape in the information.

At to begin with, the group thought the change was caused by a billow of plasma inside the Milky Way that happened to go amongst Earth and the blazar, dissipating its light. Yet, at that point a similar thing happened again in 2014.

Discussions with associates at different observatories uncovered that the universe carried on a similar way when seen in numerous electromagnetic wavelengths, not simply with a radio telescope. That wouldn't occur if a stray billow of plasma were at fault.

Presently, Readhead and his associates contend that they're seeing the blazar's dark gap emanate minor burps of plasma, amplified many circumstances by another sort of gravitational focal point. These inestimable focal points are enormous articles that can twist the way of light going by them, making wellsprings of light out of sight look misshaped from the perspective of telescopes on Earth. Space experts can utilize this mutilation to find out about the foundation objects and their focal points.

Up until now, all known focal points have either been huge — a large number of times the mass of the sun, similar to a whole cosmic system — or moderately little, similar to a solitary planet.

The focal point that amplified J1415+1320 is by all accounts something in the middle of, from 1,000 to 1 million times the mass of the sun. It is around 2.7 billion light-years away, and is related with a winding cosmic system, however is less gigantic than the whole world. The focal point could exist in or adjacent the system, and could be a gathering of thousands of stars like a globular bunch. Or, then again it could be something more extraordinary, as hard to-spot moderate size dark gaps.

The U-formed components in the information showed up when the dark opening discharged bunches of issue that hurried away at close to the speed of light, and go behind this focal point from the viewpoint of Earth, the group says.

Presently "U" see it

Far off world J1415+1320 diminished and lit up finished the course of a year in 2009 and 2014 (shaded areas), causing a U-molded plunge in the information used to track its brilliance. That plunge was caused by blobs of hot plasma transmitted by the world's dark opening, which were amplified by a group of stars going about as an enormous focal point amongst Earth and the cosmic system, specialists propose. This plot indicates perceptions of the cosmic system from the Owens Valley Radio Observatory in California (dark), the Metsähovi Radio Observatory in Finland (blue) and the Submillimeter Array in Hawaii (red).

"This was a to a great degree intriguing, novel perception," says astrophysicist Eileen Meyer of the University of Maryland, Baltimore County. "To the extent I know, there's in no way like that that has been seen some time recently."

Readhead's group still needs to mention more objective facts to affirm that the focal point is genuine. In any case, in the event that it will be, it could help explain an extraordinary secret about dark openings: how they shoot planes of hot charged particles into space. Numerous dynamic systems show these splendid planes, however their starting points are secretive.

The new perceptions of J1415+1320 are not exactly such a picture. Be that as it may, they propose an approach to sometime deliver one. The focal point amplified the dark opening 100 times more than is conceivable with current telescopes, so more perceptions could help uncover more about its inclination.

"This resembles a venturing stone," Vedantham says. "This is a conceivable system to go in and get this high-determination perspective of how a dark gap is propelling these planes."

In the event that further perceptions discount the focal point, at that point things could get considerably more interesting. "In the event that it's not a gravitational focal point, at that point it's a natural property of the planes themselves," Readhead says. "At that point it will have intriguing ramifications for the material science of the genuine fly. I believe it's a win-win circumstance."

#astronomy

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