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July 04, 2022, 11:35:36 am

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A Logarithmic Map of the Entire Observable Universe

Among the scientific community, it's widely believed that so far humans have only discovered about 5% of the universe.

Yet, despite knowing about just a fraction of what's out there, we've still managed to discover galaxies billions of light-years away from Earth.

This graphic by Pablo Carlos Budassi provides a logarithmic map of the entire known universe, using data by researchers at Princeton University and updated as of May 2022.

CLICK HERE:
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THE SOCIETY FOR POPULAR ASTRONOMY Electronic News Bulletin No. 569 2022 July 3


We're delighted that the Society for Popular Astronomy's free Electronic News Bulletins have gained many hundreds of subscribers since we first issued them more than 23 years ago!

They remain free, but if you are not already a member of the SPA, we hope you will consider joining, and supporting the UK's liveliest astronomical society, with members worldwide. You can easily sign up online. https://www.popastro.com/main_...

And now, here is our latest round-up of news.

PERSEVERANCE STUDIES WILD WINDS OF JEZERO CRATER
NASA

During its first couple hundred days in Jezero Crater, NASA's Perseverance Mars rover saw some of the most intense dust activity ever witnessed by a mission sent to the Red Planet's surface. Not only did the rover detect hundreds of dust-bearing whirlwinds called dust devils, Perseverance captured the first video ever recorded of wind gusts lifting a massive Martian dust cloud. The new findings enable scientists to better understand dust processes on Mars and contribute to a body of knowledge that could one day help them predict the dust storms that Mars is famous for - and that pose a threat to future robotic and human explorers. The study authors found that at least four whirlwinds pass Perseverance on a typical Martian day and that more than one per hour passes by during a peak hourlong period just after noon. The rover's cameras also documented three occasions in which wind gusts lifted large dust clouds, something the scientists call "gust-lifting events." The biggest of these created a massive cloud covering 4 square kilometres. A key objective for Perseverance's mission on Mars is astrobiology, including the search for signs of ancient microbial life. The rover will characterize the planet's geology and past climate, pave the way for human exploration of the Red Planet, and be the first mission to collect and cache Martian rock and regolith (broken rock and dust).

HOW AURORA ON MARS IS FORMED
University of Iowa

Physicists have studied discrete aurora, a light-in-the-sky display that occurs mostly during the night in the southern hemisphere of Mars . While scientists have known about discrete aurora on Mars-which also occur on Earth -- they did not know how they formed. That's because Mars does not have a global magnetic field like Earth, which is a main trigger for aurora, also called the northern and southern lights on our planet. Instead, the physicists report, discrete aurora on Mars are governed by the interaction between the solar wind -- the constant jet of charged particles from the Sun -- and magnetic fields generated by the crust at southern latitudes on Mars. It's the nature of this localized interaction between the solar wind and the crustal magnetic fields that lead to discrete aurora, the scientists find. The findings come from more than 200 observations of discrete aurora on Mars by the NASA-led Mars Atmosphere and Volatile EvolutioN (MAVEN) spacecraft.

FIRST ANALYSIS OF ROCKS FROM ASTEROID RYUGU
University of Chicago

In 2018, Hayabusa2 landed atop a moving asteroid named Ryugu and collected particles from above and below its surface. After spending a year and a half orbiting the asteroid, it returned to Earth with a sealed capsule containing about five grams of dust and rock. Scientists around the world have been eagerly anticipating the unique sample -- one that could help redefine our understanding of how planets evolve and how our solar system formed. Scientists are particularly excited because these particles would never have reached Earth without the protective barrier of a spacecraft. The rock is similar to a class of meteorites known as "Ivuna-type carbonaceous chondrites. These rocks have a similar chemical composition to what we measure from the Sun and are thought to date back to the very beginnings of the solar system approximately four-and-a-half billion years ago -- before the formation of the Sun, the Moon and Earth. Back then, all that existed was a gigantic, rotating cloud of gas. Scientists think that most of that gas was pulled into the centre and formed the star we know as the Sun. As the remnants of that gas expanded into a disk and cooled, it transformed into rocks, which still float around the solar system today; it appears Ryugu may be one of them. Scientists said the fragments show signs of having been soaked in water at some point. Using radioisotope dating, they estimated that Ryugu was altered by water circulation only about five million years after the solar system formed. These findings are particularly interesting to researchers because they hint at similar formation conditions between comets and some asteroids such as Ryugu. The scientists noted that a percentage of the find will be set aside so that we can analyze them in the future with more advanced technology -- much as we did with lunar samples from Apollo. This mission is the first of several international missions that will bring back samples from another asteroid named Bennu, as well as unexplored areas on our moon, Mars, and Mars' moon Phobos. This should all be taking place in the next 10 to 20 years.

LARGE NUMBER OF BROWN DWARFS DISCOVERED
University of Bern

Brown dwarfs are mysterious astronomical objects that fill the gap between the heaviest planets and the lightest stars, with a mix of stellar and planetary characteristics. Due to this hybrid nature, these puzzling objects are crucial to improve our understanding of both stars and giant planets. Brown dwarfs orbiting a parent star from sufficiently far away are particularly valuable as they can be directly photographed -- unlike those that are too close to their star and are thus hidden by its brightness. This provides scientists with a unique opportunity to study the details of the cold, planet-like atmospheres of brown dwarf companions. However, despite remarkable efforts in the development of new observing technologies and image processing techniques, direct detections of brown dwarf companions to stars have remained rather sparse, with only around 40 systems imaged in almost three decades of searches. Researchers have now directly imaged four new brown dwarfs. Wide-orbit brown dwarf companions are rare to start with, and detecting them directly poses huge technical challenges since the host stars completely blind our telescopes. Most surveys conducted so far have been blindly targeting random stars from young clusters. An alternative approach to increase the number of detections is to only observe stars that show indications of an additional object in their system. For example, the way a star moves under the gravitational tug of a companion can be an indicator of the existence of that companion, whether it is a star, a planet or something in between. The team developed the COPAINS tool which predicts the types of companions that could be responsible for observed anomalies in stellar motions. Applying the COPAINS tool the research team carefully selected 25 nearby stars that seemed promising for the direct detection of hidden, low-mass companions based on data from the Gaia spacecraft of the European Space Agency (ESA). Using then the SPHERE planet-finder at the Very Large Telescope in Chile to observe these stars, they successfully detected ten new companions with orbits ranging from that of Jupiter to beyond that of Pluto, including five low-mass stars, a white dwarf (a dense stellar remnant), and a remarkable four new brown dwarfs. These findings significantly advance the number of known brown dwarfs orbiting stars from large distances, with a major boost in detection rate compared to any previous imaging survey. While for now this approach is mostly limited to signatures from brown dwarf and stellar companions, future phases of the Gaia mission will push these methods to lower masses and allow for the discovery of new giant exoplanets.

EVIDENCE OF GALACTIC METAL SHROUDED IN DUST
University of California - Irvine

A thorough understanding of galaxy evolution depends in part on an accurate measurement of the abundance of metals in the intergalactic medium -- the space between stars -- but dust can impede observations in optical wavelengths. An international team of astronomers uncovered evidence of heavier elements in local galaxies -- found to be deficient in earlier studies -- by analysing infrared data gathered during a multiyear campaign. To determine the abundance of gas-phase metals in the intergalactic medium, the astronomers sought to acquire data on the ratios of proxies, oxygen and nitrogen, because infrared emissions from these elements are less obscured by galactic dust. Observing this process in infrared wavelengths is a challenge for astronomers because water vapour in Earth's atmosphere blocks radiation on this part of the electromagnetic spectrum, making measurements from even the highest-altitude ground telescopes -- like those at the Keck Observatory in Hawaii -- insufficient. Part of the dataset used by the team came from the now-retired Herschel Space Telescope, but Herschel was not equipped with a spectrometer capable of reading a specific emission line that the UCI-led team needed for its study. The researchers' solution was to take to the skies -- reaching more than 45,000 feet above sea level -- in the Stratospheric Observatory for Infrared Astronomy, NASA's Boeing 747 equipped with a 2.5-meter telescope. By analysing infrared emissions, the researchers were able to compare the metallicity of their target ultraluminous infrared galaxies with less dusty galaxies with similar mass and star formation rates. Chartab explained that these new data show that ultraluminous infrared galaxies are in line with the fundamental metallicity relation determined by stellar mass, metal abundance and star formation rate. The new data further show that the underabundance of metals derived from optical emission lines is likely due to "heavy dust obscuration associated with starburst," according to the paper.

SUPERMASSIVE BLACK HOLES INSIDE OF DYING GALAXIES
National Institutes of Natural Sciences

Astronomers used a database combining observations from the best telescopes in the world to detect the signal from the active supermassive black holes of dying galaxies in the early Universe. The appearance of these active supermassive black holes correlates with changes in the host galaxy, suggesting that a black hole could have far reaching effects on the evolution of its host galaxy. The Milky Way includes stars of various ages, including stars still forming. But in some other galaxies, known as elliptical galaxies, all of the stars are old and about the same age. This indicates that early in their histories elliptical galaxies had a period of prolific star formation that suddenly ended. Why this star formation ceased in some galaxies but not others is not well understood. One possibility is that a supermassive black hole disrupts the gas in some galaxies, creating an environment unsuitable for star formation. To test this theory, astronomers look at distant galaxies. Due to the finite speed of light, it takes time for light to travel across the void of space. The light we see from an object 10 billion light-years away had to travel for 10 billion years to reach Earth. Thus the light we see today shows us what the galaxy looked like when the light left that galaxy 10 billion years ago. So looking at distant galaxies is like looking back in time. But the intervening distance also means that distant galaxies look fainter, making study difficult.

To overcome these difficulties an international team used the Cosmic Evolution Survey (COSMOS) to sample galaxies 9.5-12.5 billion light-years away. COSMOS combines data taken by world leading telescopes, including the Atacama Large Millimeter/submillimeter Array (ALMA) and the Subaru Telescope. COSMOS includes radio wave, infrared light, visible light, and x-ray data. The team first used optical and infrared data to identify two groups of galaxies: those with ongoing star formation and those where star formation has stopped. The x-ray and radio wave data signal-to-noise ratio was too weak to identify individual galaxies. So the team combined the data for different galaxies to produce higher signal to noise ratio images of "average" galaxies. In the averaged images, the team confirmed both x-ray and radio emissions for the galaxies without star formation. This is the first time such emissions have been detected for distant galaxies more than 10 billion light-years away. Furthermore, the results show that the x-ray and radio emissions are too strong to be explained by the stars in the galaxy alone, indicating the presence of an active supermassive black hole. This black hole activity signal is weaker for galaxies where star formation is ongoing. These results show that an abrupt end in star formation in the early Universe correlates with increased supermassive black hole activity. More research is needed to determine the details of the relationship.


RAPID RADIO BURST SHOWS HOT SPACE BETWEEN GALAXIES
Cornell University

recently discovered, rare and persistent rapid-fire fast radio burst source -- sending out an occasional and informative cosmic ping from more than 3.5 billion light years away -- helps to reveal the secrets of the broiling hot space between the galaxies. Fast Radio Burst 20190520B -- a prolific repeating burst source -- was first observed in June 2019 by the Five-hundred-meter Aperture Spherical radio Telescope (FAST), in Ghizou province, southwest China. Astronomers generally consider this telescope as the spiritual successor to the now-defunct, Cornell University-built Arecibo Observatory in Puerto Rico. After FAST found the burst, scientists then pinpointed the burst's location using the Very Large Array, Socorro, New Mexico. What excites astronomers about the repeating fast radio bursts (FRBs) -- since they only burst once, generally speaking -- is that these quick-fire surges provide a pathway for scientists to comprehend the perplexing, mysterious and million-degree intergalactic medium. Four bursts were detected during the initial 24-second scan in 2019, according to the paper. Between April and September 2020, during follow-up observations, FAST detected 75.

Due to the rapidly repeating bursts, astronomers believe that FRB 20190520B may be quite young. It seems to reside in a complex plasma environment, like that expected in a young supernova remnant. So one possibility is that the highly active source may be a newborn, and if so, it paints an intriguing evolutionary picture of FRB sources, where young burst sources are associated with persistent radio emission. The persistent emission fades away as the burst repetition rate slows down. Astronomers usually assume that FRBs pass through only a modest amount of gas (free electrons) in their host galaxies, which makes counting electrons in the intergalactic medium an easier task. FRB 20190520B shows the opposite: It has encountered far more gas in its host galaxy than scientists expected, calling into question previous assumptions. Ultimately, astronomers want to know how the intergalactic medium is formed. Astronomers want to deconstruct how many free electrons are in the intergalactic medium, because it has been extremely difficult to study.


NUSTAR STUDIES X-RAY UNIVERSE FOR 10 YEARS
NASA

NASA's Nuclear Spectroscopic Telescope Array (NuSTAR) is turning 10. Launched on June 13, 2012, this space telescope detects high-energy X-ray light and studies some of the most energetic objects and processes in the Universe, from black holes devouring hot gas to the radioactive remains of exploded stars. Here are some of the ways NuSTAR has opened our eyes to the X-ray Universe over the last decade. Different colours of visible light have different wavelengths and different energies; similarly, there is a range of X-ray light, or light waves with higher energies than those human eyes can detect. NuSTAR detects X-rays at the higher end of the range. There aren't many objects in our solar system that emit the X-rays NuSTAR can detect, but the Sun does: Its high-energy X-rays come from microflares, or small bursts of particles and light on its surface. NuSTAR's observations contribute to insights about the formation of bigger flares, which can cause harm to astronauts and satellites. These studies could also help scientists explain why the Sun's outer region, the corona, is many times hotter than its surface.

NuSTAR has identified dozens of black holes hidden behind thick clouds of gas and dust. Visible light typically can't penetrate those clouds, but the high-energy X-ray light observed by NuSTAR can. This gives scientists a better estimate of the total number of black holes in the Universe. In recent years scientists have used NuSTAR data to find out how these giants become surrounded by such thick clouds, how that process influences their development, and how obscuration relates to a black hole's impact on the surrounding galaxy. NuSTAR is a kind of zombie hunter: It's deft at finding the undead corpses of stars. Known as neutron stars, these are dense nuggets of material left over after a massive star runs out of fuel and collapses. Though neutron stars are typically only the size of a large city, they are so dense that a teaspoon of one would weigh about a billion tons on Earth. Their density, combined with their powerful magnetic fields, makes these objects extremely energetic: One neutron star located in the galaxy M82 beams with the energy of 10 million Suns. During their lives, stars are mostly spherical, but NuSTAR observations have shown that when they explode as supernovae, they become an asymmetrical mess. The space telescope solved a major mystery in the study of supernovae by mapping the radioactive material left over by two stellar explosions, tracing the shape of the debris and in both cases revealing significant deviations from a spherical shape. Because of NuSTAR's X-ray vision, astronomers now have clues about what happens in an environment that would be almost impossible to probe directly. The NuSTAR observations suggest that the inner regions of a star are extremely turbulent at the time of detonation.

Bulletin compiled by Clive Down

The Society for Popular Astronomy has been helping beginners in amateur astronomy -- and more experienced observers -- for over 60 years. If you are not a member, you may be missing something. Membership rates are extremely reasonable, starting at just £25 a year in the UK. You will receive our bright bi-monthly magazine Popular Astronomy, help and advice in pursuing your hobby, the chance to hear top astronomers at our regular meetings, and other benefits. The best news is that you can join online right now with a credit or debit card at our lively website: www.popastro.com
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Astronomy / The Night Sky in July
July 01, 2022, 08:20:50 pm
All the bright planets make an appearance this month. The inferior planets, so called, Venus and Mercury lie low in the eastern sky before sunrise, with the former nicely tangled in the stars of the Hyades in early July. Jupiter lies near the celestial equator in Pisces and grows fat and bright and ideal for telescopic observing. Saturn, too, looks great in a telescope as it slowly grows bigger. This month also brings the largest Full Moon of the year. And don't forget about the Milky Way emerging in the darkening east-south-eastern sky after sunset. Turn your optics along this spectacular river of stars to glimpse the many clusters, nebulae, and star clouds in our part of the galaxy. Here's what's in the night sky this month...


TO FIND OUT MORE CLICK HERE
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THE SOCIETY FOR POPULAR ASTRONOMY Electronic News Bulletin No. 568 2022 June 19

We're delighted that the Society for Popular Astronomy's free Electronic News Bulletins have gained many hundreds of subscribers since we first issued them more than 23 years ago!
They remain free, but if you are not already a member of the SPA, we hope you will consider joining, and supporting the UK's liveliest astronomical society, with members worldwide. You can easily sign up online. https://www.popastro.com/main_...
And now, here is our latest round-up of news.

EARTH'S MAGNETIC POLES UNLIKELY TO FLIP
Lund University

The emergence of a mysterious area in the South Atlantic where the geomagnetic field strength is decreasing rapidly, has led to speculation that Earth is heading towards a magnetic polarity reversal. However, a new study that pieces together evidence stretching back 9,000 years, suggests that the current changes aren't unique, and that a reversal may not be in the cards after all. The Earth's magnetic field acts as an invisible shield against the life-threatening environment in space, and solar winds that would otherwise sweep away the atmosphere. However, the magnetic field is not stable, and at irregular intervals at an average of every 200,000 years polarity reversals happen. This means that the magnetic North and South poles swap places. During the past 180 years, Earth's magnetic field strength has decreased by about 10 percent. Simultaneously, an area with an unusually weak magnetic field has grown in the South Atlantic off the coast of South America. This area, where satellites have malfunctioned several times due to exposure to highly charged particles from the Sun, is called the South Atlantic Anomaly. These developments have led to speculation that we may be heading for a polarity reversal. However, the new study suggests this may not be the case. The results are based on analyses of burnt archaeological artifacts, volcanic samples and sediment drill cores, all of which carry information about the Earth's magnetic field. These include clay pots that have been heated up to over 580 degrees Celsius, volcanic lava that has solidified, and sediments that have been deposited in lakes or in the sea. The objects act as time capsules, and carry information about the magnetic field in the past. Using sensitive instruments, the researchers have been able to measure these magnetizations and recreate the direction and strength of the magnetic field at specific places and times. By studying how the magnetic field has changed, researchers can learn more about the underlying processes in the Earth's core that generate the field. The new model can also be used to date both archaeological and geological records, by comparing measured and modelled variations in the magnetic field. And reassuringly, it has led them to a conclusion regarding speculations about an imminent polarity reversal:

CHINA LAUNCHES 3RD CREWED MISSION TO TIANGONG SPACE STATION
CMSA

China has successfully launched another manned mission to its new space station, sending three astronauts who will continue construction work for six months, The team will live and work at the Tiangong Space Station's Tianhe core module for six months before returning to Earth in December. Tiangong means Heavenly Palace. This is the third crewed mission during the construction of the space station, which China plans to have fully crewed and operational by December 2022. The first crewed mission, a three-month stay by three other astronauts, was completed in September 2021. The second, Shenzhou-13, saw three astronauts spend six months in space for the first time. Six months is the standard mission duration for many countries -- but it is an important opportunity for Chinese astronauts to become accustomed to a long-term stay in space and help prepare future astronauts to do the same. Six space missions have been scheduled before the end of the year, including another crewed mission, two laboratory modules and two cargo missions. The modules will be assembled into a T-shaped structure, along with the Tianhe core cabin -- the main living space for the astronauts -- which will be expanded from 50 cubic metres to 110 cubic metres. At the end of the Shenzhou-14 mission, another three astronauts are expected to rotate and live with the crew for five to 10 days, bringing the number of Chinese astronauts in space at the same time to a record six.
Once construction is completed, the Tiangong space station is expected to last for 15 years. China plans to launch two crewed missions and two cargo missions to the station every year The Shenzhou-13 mission last year was a major step for the country's young space program, which is rapidly becoming one of the world's most advanced. China's space program was late to the game, only established in the early 1970s, years after American astronaut Neil Armstrong had already landed on the Moon. But the chaos of China's Cultural Revolution stopped the nation's space effort in its tracks -- and progress was postponed until the early 1990s. The government has since invested billions of dollars into the space program -- and the payoff has been evident. China successfully landed an exploratory rover on the Moon in December 2020 and one on Mars in May 2021. The first module of the Tiangong Space Station launched in April 2021. China's ambitions span years into the future, with grand plans for space exploration, research and commercialization. One of the biggest ventures will be building a joint China-Russia research station on the Moon's south pole by 2035 -- a facility that will be open to international participation.

THE VENUS CLOUD DISCONTINUITY
Spaceweather.com

The Venus Cloud Discontinuity is a relatively new discovery, photographed by Japan's Venus orbiter Akatsuki in 2016 and first spotted by JAXA scientist Javier Peralta. The massive structure cuts vertically across Venus's equator, stretching almost 5000 miles from end to end, and circles the planet faster than 200 mph, making one lap every ~5 Earth days. Researchers following up on the discovery soon stumbled onto another surprise. Older photographs of Venus showed it, too. The Cloud Discontinuity] is a recurrent phenomenon that has gone unnoticed since at least the year 1983. How do you overlook something so big? Visually, the Cloud Discontinuity is hidden underneath Venus's opaque cloudtops. To see it, you have to use an infrared filter, which reveals heat trickling up from below. Indeed, this is how amateurs are tracking the disturbance: Researchers still aren't sure what the Cloud Discontinuity is. Whatever it is, the structure might help solve a longstanding mystery: Why does Venus's atmosphere rotate so much faster than the planet itself? The hot, deadly air on Venus spins nearly 60 times faster than its surface, an effect known as "super-rotation." Venus's Cloud Discontinuity could be assisting the spin-up by transporting angular momentum from the deep atmosphere to the cloudtops.

GRAVITATIONAL WAVES DETECT NEW PARTICLES AROUND BLACK HOLES
Universiteit van Amsterdam

Clouds of ultralight particles can form around rotating black holes. A team of physicists now show that these clouds would leave a characteristic imprint on the gravitational waves emitted by binary black holes. Black holes are generally thought to swallow all forms of matter and energy surrounding them. It has long been known, however, that they can also shed some of their mass through a process called superradiance. While this phenomenon is known to occur, it is only effective if new, so far unobserved particles with very low mass exist in nature, as predicted by several theories beyond the Standard Model of particle physics. When mass is extracted from a black hole via superradiance, it forms a large cloud around the black hole, creating a so-called gravitational atom. Despite the immensely larger size of a gravitational atom, the comparison with sub-microscopic atoms is accurate because of the similarity of the black hole plus its cloud with the familiar structure of ordinary atoms, where clouds of electrons surround a core of protons and neutrons. In the new work, the researchers studied the gravitational equivalent of the so-called 'photoelectric effect'. In this well-known process, which for example is exploited in solar cells to produce an electric current, ordinary electrons absorb the energy of incident particles of light and are thereby ejected from a material -- the atoms 'ionize'. In the gravitational analogue, when the gravitational atom is part of a binary system of two heavy objects, it gets perturbed by the presence of the massive companion, which could be a second black hole or a neutron star. Just as the electrons in the photoelectric effect absorb the energy of the incident light, the cloud of ultralight particles can absorb the orbital energy of the companion, so that some of the cloud gets ejected from the gravitational atom. The team demonstrated that this process may dramatically alter the evolution of such binary systems, significantly reducing the time required for the components to merge with each other. Moreover, the ionization of the gravitational atom is enhanced at very specific distances between the binary black holes, which leads to sharp features in the gravitational waves that we detect from such mergers. Future gravitational wave interferometers -- machines similar to the LIGO and Virgo detectors that over the past few years have shown us the first gravitational waves from black holes -- could observe these effects. Finding the predicted features from gravitational atoms would provide distinctive evidence for the existence of new ultralight particles.

LIFECYCLE OF ANCESTOR GALAXY 'CITIES'
Kavli Institute for the Physics and Mathematics of the Universe

For the first time, researchers have created simulations that directly recreate the full life cycle of some of the largest collections of galaxies observed in the distant Universe 11 billion years ago. Cosmological simulations are crucial to studying how the Universe became the shape it is today, but many do not typically match what astronomers observe through telescopes. Most are designed to match the real Universe only in a statistical sense. Constrained cosmological simulations, on the other hand, are designed to directly reproduce the structures we actually observe in the Universe. However, most existing simulations of this kind have been applied to our local Universe, meaning close to Earth, but never for observations of the distant Universe. A team of researchers, were interested in distant structures like massive galaxy protoclusters, which are ancestors of present-day galaxy clusters before they could clump under their own gravity. They found current studies of distant protoclusters were sometimes oversimplified, meaning they were done with simple models and not simulations. Their result was COSTCO (COnstrained Simulations of The COsmos Field). Developing the simulation was much like building a time machine. Because light from the distant Universe is only reaching Earth now, the galaxies telescopes observe today are a snapshot of the past. In this sense, the researchers took snapshots of "young" grandparent galaxies in the Universe and then fast forwarded their age to study how clusters of galaxies would form. The light from galaxies the researchers used travelled a distance of 11 billion light-years to reach us.
Another important reason why the researchers created these simulations was to test the standard model of cosmology, that is used to describe the physics of the Universe. By predicting the final mass and final distribution of structures in a given space, researchers could unveil previously undetected discrepancies in our current understanding of the Universe. Using their simulations, the researchers were able to find evidence of three already published galaxy protoclusters and disfavor one structure. On top of that, they were able to identify five more structures that consistently formed in their simulations. This includes the Hyperion proto-supercluster, the largest and earliest proto-supercluster known today that is 5000 times the mass of our Milky Way galaxy, which the researchers found out it will collapse into a large 300 million light year filament. Their work is already being applied to other projects including those to study the cosmological environment of galaxies, and absorption lines of distant quasars to name a few.

RUSSIA ILLEGALLY PLANS TO RESTART GERMAN TELESCOPE

Russian space agency Roscosmos says it will restart a telescope shut down by Germany over Moscow's invasion of Ukraine. But a noted expert has warned that this might be dangerous to the instrument. The X-ray telescope, named eROSITA, works in tandem with a Russian instrument, the ART-XC, to scan distant galaxies in what was a joint German-Russian mission until Germany put its cooperation on ice over Russia's invasion. The telescope was launched into space from the Baikonur launch site in July 2019. However, the scientific director of the Spekr-RG project said that attempts to restart the telescope without German cooperation could be detrimental to the device itself. The recommissioning could take place only with Germany's consent; otherwise, the telescope would be in danger of breaking down. The Spektr-RG mission on which it is deployed along with the Russian telescope aims, among other things, to detect black holes.  Until eROSITA was put into sleep mode on February 26, two days after Russia started its invasion, Russian and German researchers had been able to jointly evaluate the data sent by the two devices. At the time it was shut down, eROSITA had completed four of its planned eight full-sky surveys. Data from the first four are still being evaluated by scientists.
Bulletin compiled by Clive Down
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Fascinating!
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I really am off to fill the car up tomorrow!!!!   :-X  :-X
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Done as you suggest Colin ::)
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Quote from: welshcol on June 11, 2022, 03:54:28 pmHi Geooff -so sorry to hear of your understandably very distressing experience.
 Trust you will soon be fully recovered and back to normal.
Take care with Best Wishes 👍👍

Re-read the final sentence Colin!!!
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FIRST OF ALL, THANKS EVERYONE for your concern and support. I'm fine now, just a little stressed, but I'll be ok.
For those of you who don't know what happened, I was robbed this morning at a petrol station in H'west.
I managed to pull myself together even though my hands were still shaking. I felt dizzy and I honestly think I was probably in shock.

My money was gone. I called the police who were quick on the scene and fantastic, they quickly called for an ambulance because my blood pressure and heart rate were so high.

The police asked me if I knew who did it and I said "yes it was pump number 3"   ;)
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THE SOCIETY FOR POPULAR ASTRONOMY Electronic News Bulletin No. 567 2022 June 5
We're delighted that the Society for Popular Astronomy's free Electronic News Bulletins have gained many hundreds of subscribers since we first issued them more than 23 years ago!
They remain free, but if you are not already a member of the SPA, we hope you will consider joining, and supporting the UK's liveliest astronomical society, with members worldwide. You can easily sign up online. https://www.popastro.com/main_...
And now, here is our latest round-up of news.

WHY URANUS AND NEPTUNE ARE DIFFERENT COLOURS
Association of Universities for Research in Astronomy (AURA)

Astronomers may now understand why the similar planets Uranus and Neptune are different colours. Using observations from the Gemini North telescope, the NASA Infrared Telescope Facility, and the Hubble Space Telescope, researchers have developed a single atmospheric model that matches observations of both planets. The model reveals that excess haze on Uranus builds up in the planet's stagnant, sluggish atmosphere and makes it appear a lighter tone than Neptune. Neptune and Uranus have much in common -- they have similar masses, sizes, and atmospheric compositions -- yet their appearances are notably different. At visible wavelengths Neptune has a distinctly bluer colour whereas Uranus is a pale shade of cyan. Astronomers now have an explanation for why the two planets are different colours. New research suggests that a layer of concentrated haze that exists on both planets is thicker on Uranus than a similar layer on Neptune and 'whitens' Uranus's appearance more than Neptune's . If there were no haze in the atmospheres of Neptune and Uranus, both would appear almost equally blue. This conclusion comes from a model that an international team developed to describe aerosol layers in the atmospheres of Neptune and Uranus. Previous investigations of these planets' upper atmospheres had focused on the appearance of the atmosphere at only specific wavelengths. However, this new model, consisting of multiple atmospheric layers, matches observations from both planets across a wide range of wavelengths. The new model also includes haze particles within deeper layers that had previously been thought to contain only clouds of methane and hydrogen sulphide ices.
The team's model consists of three layers of aerosols at different heights. The key layer that affects the colours is the middle layer, which is a layer of haze particles (referred to in the paper as the Aerosol-2 layer) that is thicker on Uranus than on Neptune. The team suspects that, on both planets, methane ice condenses onto the particles in this layer, pulling the particles deeper into the atmosphere in a shower of methane snow. Because Neptune has a more active, turbulent atmosphere than Uranus does, the team believes Neptune's atmosphere is more efficient at churning up methane particles into the haze layer and producing this snow. This removes more of the haze and keeps Neptune's haze layer thinner than it is on Uranus, meaning the blue colour of Neptune looks stronger. To create this model, the team analysed a set of observations of the planets encompassing ultraviolet, visible, and near-infrared wavelengths (from 0.3 to 2.5 micrometres) taken with the Near-Infrared Integral Field Spectrometer (NIFS) on the Gemini North telescope near the summit of Maunakea in Hawai'i -- which is part of the international Gemini Observatory, a Program of NSF's NOIRLab -- as well as archival data from the NASA Infrared Telescope Facility, also located in Hawai'i, and the NASA/ESA Hubble Space Telescope. The NIFS instrument on Gemini North was particularly important to this result as it is able to provide spectra -- measurements of how bright an object is at different wavelengths -- for every point in its field of view. This provided the team with detailed measurements of how reflective both planets' atmospheres are across both the full disk of the planet and across a range of near-infrared wavelengths. The model also helps explain the dark spots that are occasionally visible on Neptune and less commonly detected on Uranus. While astronomers were already aware of the presence of dark spots in the atmospheres of both planets, they didn't know which aerosol layer was causing these dark spots or why the aerosols at those layers were less reflective. The team's research sheds light on these questions by showing that a darkening of the deepest layer of their model would produce dark spots similar to those seen on Neptune and perhaps Uranus.
PLANETS OF BINARY STARS MIGHT SUPPORT LIFE FORMS
University of Copenhagen - Faculty of Science
Nearly half of Sun-size stars are binary. According to University of Copenhagen research, planetary systems around binary stars may be very different from those around single stars. This points to new targets in the search for extraterrestrial life forms. Since the only known planet with life, the Earth, orbits the Sun, planetary systems around stars of similar size are obvious targets for astronomers trying to locate extraterrestrial life. Nearly every second star in that category is a binary star. New research indicates that planetary systems are formed in a very different way around binary stars than around single stars such as the Sun. The new discovery has been made based on observations made by the ALMA telescopes in Chile of a young binary star about 1,000 lightyears from Earth. The binary star system, NGC 1333-IRAS2A, is surrounded by a disc consisting of gas and dust. The observations can only provide researchers with a snapshot from a point in the evolution of the binary star system. However, the team has complemented the observations with computer simulations reaching both backwards and forwards in time. Notably, the movement of gas and dust does not follow a continuous pattern. At some points in time -- typically for relatively shorts periods of ten to one hundred years every thousand years -- the movement becomes very strong. The binary star becomes ten to one hundred times brighter, until it returns to its regular state. Presumably, the cyclic pattern can be explained by the duality of the binary star. The two stars encircle each other, and at given intervals their joint gravity will affect the surrounding gas and dust disc in a way which causes huge amounts of material to fall towards the star. The observed stellar system is still too young for planets to have formed. The team hopes to obtain more observational time at ALMA, allowing to investigate the formation of
Very soon the new James Webb Space Telescope (JWST) will join the search for extraterrestrial life. Near the end of the decade, JWST will be complemented by the ELT (European Large Telescope) and the extremely powerful SKA (Square Kilometer Array) both planned to begin observing in 2027. The ELT will with its 39-meter mirror be the biggest optical telescope in the world and will be poised to observe the atmospheric conditions of exoplanets (planets outside the Solar System, ed.). SKA will consist of thousands of telescopes in South Africa and in Australia working in coordination and will have longer wavelengths than ALMA. The team has had observation time on the ALMA telescopes in Chile to observe the binary star system NGC 1333-IRAS2A in the Perseus molecular cloud. The distance from Earth to the binary star is about 1,000 lightyears which is a quite short distance in an astronomical context. Formed some 10,000 years ago, it is a very young star. The two stars of the binary system are 200 astronomical units (AUs) apart. An AU equals the distance from Earth to the Sun. In comparison, the furthest planet of the Solar System, Neptune, is 30 AUs from the Sun.

JAMES WEBB TARGETS ANNOUNCED
NASA

Over the past five months, the James Webb Space Telescope and the joint NASA, European Space Agency, and Canadian Space Agency teams behind the project have been working towards the completion of the observatory's six-month-long commissioning phase at the Sun-Earth Lagrange point 2 (L2). With the observatory's mirrors recently completing alignment, Webb and its teams are preparing for the all-important and historic first image from the observatory. As teams continue to work towards completing commissioning, some of the first scientific research targets of Webb's operational phase have been announced, including two strange and intriguing exoplanets that exhibit unique characteristics. After confirming that all of the optical and structural systems are operating as planned, James Webb's commissioning phase will be complete and the observatory will assume operational status. Webb and its science teams have already lined up a plethora of research targets for the first few weeks of the observatory's operational phase, some of which may produce images as we've never seen before from other telescopes. Among the many research targets outlined for Webb's first few weeks of operation are two exoplanets that exhibit unique characteristics: 55 Cancri e and LHS 3844 b. 55 Cancri e is an extremely hot super-Earth exoplanet located 41 light-years away in the constellation Cancer, where it orbits its Sun-like parent star 55 Cancri A. The exoplanet is around double the diameter of Earth and is around 8.63 Earth masses. At the time of its discovery in August 2004, it was the first super-Earth to be found. Orbiting just 1.5 million miles from 55 Cancri A, the exoplanet completes one orbit around its parent star in just 18 hours and is thought to feature oceans of lava on its dayside due to its extremely hot surface temperatures. What's more, 55 Cancri e is likely tidally locked due to its close proximity to 55 Cancri A. This would be expected to ensure that the parts of the surface facing the star most directly would be the hottest region of the planet. Telescope data from NASA's Spitzer Space Telescope, however, suggests otherwise - showing that the exoplanet's hottest region is offset from this position. Spitzer data also indicates that the total amount of heat on the dayside of the planet varies.
One of the leading theories behind the Spitzer observations is that 55 Cancri e may have a thick and dynamic atmosphere that moves heat around the planet from various regions. Another theory behind the occurrence could be that 55 Cancri e isn't actually tidally locked, and is instead more like Mercury: orbiting on its axis three times for every two orbits it completes around 55 Cancri A in what is called a 3:2 resonance. The 3:2 resonance scenario would cause 55 Cancri e's surface to heat up, melt, and vaporise into the exoplanet's atmosphere. When the vapour eventually cools in the evening, it could condense and form droplets of lava that would subsequently rain onto the exoplanet's surface. To truly determine the cause of 55 Cancri e's heat distribution, Webb teams will use the observatory's Near-Infrared Camera (NIRCam) and Mid-Infrared Instrument (MIRI) in different ways to test each theory. When testing the first theory involving a thick atmosphere, teams will use NIRCam and MIRI to view the thermal emission spectrum from the dayside. To test the second theory wherein the exoplanet isn't tidally locked, teams will use NIRCam to observe and measure the heat emitted from the dayside over four orbits, allowing teams to measure each hemisphere of the exoplanet twice if the exoplanet truly has a 3:2 resonance. This allows teams to observe whether there are any differences between the planet's two hemispheres.
Another research target for Webb is another extremely hot super-Earth exoplanet named LHS 3844 b. Located 49 light-years away orbiting red dwarf LHS 3488, LHS 3488 b - like 55 Cancri e - orbits extremely close to its parent star, completing one orbit around it in just 11 hours. LHS 3488 b's parent star is a red dwarf, meaning it is much cooler and smaller than Sun-like stars such as 55 Cancri A. Due to its parent star's small size, LHS 3488 b is not hot enough to have a molten surface like 55 Cancri e and Spitzer data suggests it likely does not have an atmosphere surrounding it. The lack of an atmosphere around LHS 3488 b gives scientists the chance to carry out a thorough examination of possible rock formations and other surface characteristics using telescopes. Although Webb is not capable of imaging the exoplanet's surface directly, teams can use spectroscopy to study it. Webb's observations of 55 Cancri e and LHS 3488 b are part of the observatory's Cycle 1 General Observer program. Under the General Observers program, scientists can submit research targets for Webb to observe for their research. This same process is also used with the Hubble telescope to allocate time for scientists.

HIDDEN TROVE OF MASSIVE BLACK HOLES
University of North Carolina at Chapel Hill

A team of researchers has found a previously overlooked treasure trove of massive black holes in dwarf galaxies. The newly discovered black holes offer a glimpse into the life story of the supermassive black hole at the centre of our own Milky Way galaxy. As a giant spiral galaxy, the Milky Way is believed to have been built up from mergers of many smaller dwarf galaxies. For example, the Magellanic Clouds seen in the southern sky are dwarf galaxies that will merge into the Milky Way. Each dwarf that falls in may bring with it a central massive black hole, tens or hundreds of thousands of times the mass of our Sun, potentially destined to be swallowed by the Milky Way's central supermassive black hole. But how often dwarf galaxies contain a massive black hole is unknown, leaving a key gap in our understanding of how black holes and galaxies grow together. New research helps to fill in this gap by revealing that massive black holes are many times more common in dwarf galaxies than previously thought. Black holes are typically detected when they are actively growing by ingesting gas and stardust swirling around them, which makes them glow intensely. The problem is, while growing black holes glow with distinctive high-energy radiation, young newborn stars can too. Traditionally, astronomers have differentiated growing black holes from new star formation using diagnostic tests that rely on detailed features of each galaxy's visible light when spread out into a spectrum like a rainbow. The path to discovery began when researchers tried to apply these traditional tests to galaxy survey data. The team realized that some of the galaxies were sending mixed messages -- two tests would indicate growing black holes, but a third would indicate only star formation.
Scientists took on the challenge of constructing a new census of growing black holes, with attention to both traditional and mixed-message types. They obtained published measurements of visible light spectral features to test for black holes in thousands of galaxies found in two surveys, RESOLVE and ECO. These surveys include ultraviolet and radio data ideal for studying star formation, and they have an unusual design: Whereas most astronomical surveys select samples that favor big and bright galaxies, RESOLVE and ECO are complete inventories of huge volumes of the present-day universe in which dwarf galaxies are abundant. More than 80 percent of all growing black holes found in dwarf galaxies belonged to the new type. The group led an exhaustive search for alternative explanations involving star formation, modelling uncertainties, or exotic astrophysics. In the end, the team was forced to conclude that the newly identified black holes were real.

STARS IN DISTANT GALAXIES MORE MASSIVE THAN EXPECTED
University of Copenhagen - Faculty of Science

Astrophysicists have arrived at a major result regarding star populations beyond the Milky Way. The result could change our understanding of a wide range of astronomical phenomena, including the formation of black holes, supernovae and why galaxies die. Since 1955, it has been assumed that the composition of stars in the Universe's other galaxies is similar to that of the hundreds of billions of stars within our own -- a mixture of massive, medium mass and low mass stars. But with the help of observations from 140,000 galaxies across the Universe and a wide range of advanced models, the team has tested whether the same distribution of stars apparent in the Milky Way applies elsewhere. The answer is no. Stars in distant galaxies are typically more massive than those in our "local neighbourhood." The finding has a major impact on what we think we know about the Universe. The mass of stars tells astronomers a lot. If you change mass, you also change the number of supernovae and black holes that arise out of massive stars. As such, this result means that we'll have to revise many of the things we once presumed, because distant galaxies look quite different from our own. Researchers assumed that the size and weight of stars in other galaxies was similar to our own for more than fifty years, for the simple reason that they were unable to observe them through a telescope, as they could with the stars of our own galaxy. Distant galaxies are billions of light-years away.
As a result, only light from their most powerful stars ever reaches Earth. This has been a headache for researchers around the world for years, as they could never accurately clarify how stars in other galaxies were distributed, an uncertainty that forced them to believe that they were distributed much like the stars in our Milky Way. We've only been able to see the tip of the iceberg and known for a long time that expecting other galaxies to look like our own was not a particularly good assumption to make. However, no one has ever been able to prove that other galaxies form different populations of stars. This study has allowed us to do just that, which may open the door for a deeper understanding of galaxy formation and evolution. In the study, the researchers analyzed light from 140,000 galaxies using the COSMOS catalogue, a large international database of more than one million observations of light from other galaxies. These galaxies are distributed from the nearest to farthest reaches of the Universe, from which light has travelled a full twelve billion years before being observable on Earth.

'COSMIC TELESCOPE' STUDIES HEART OF YOUNG UNIVERSE
North Carolina State University

A unique new instrument, coupled with a powerful telescope and a little help from nature, has given researchers the ability to peer into galactic nurseries at the heart of the young Universe. After the big bang some 13.8 billion years ago, the early Universe was filled with enormous clouds of neutral diffuse gas, known as Damped Lyman-α systems, or DLAs. These DLAs served as galactic nurseries, as the gasses within slowly condensed to fuel the formation of stars and galaxies. They can still be observed today, but it isn't easy. Currently, astrophysicists use quasars -- supermassive black holes that emit light -- as "backlight" to detect the DLA clouds. And while this method does allow researchers to pinpoint DLA locations, the light from the quasars only acts as small skewers through a massive cloud, hampering efforts to measure their total size and mass. But astronomers at the W.M. Keck Observatory in Hawaii, found a way around the problem by using a gravitationally lensed galaxy and integral field spectroscopy to observe two DLAs -- and the host galaxies within -- that formed around 11 billion years ago, not long after the big bang. The advantage to this is twofold: One, the background object is extended across the sky and bright, so it is easy to take spectrum readings on different parts of the object. Two, because lensing extends the object, you can probe very small scales. For example, if the object is one light year across, we can study small bits in very high fidelity.
Spectrum readings allow astrophysicists to "see" elements in deep space that are not visible to the naked eye, such as diffuse gaseous DLAs and the potential galaxies within them. Normally, gathering the readings is a long and painstaking process. But the team solved that issue by performing integral field spectroscopy with the Keck Cosmic Web Imager. Integral field spectroscopy allowed the researchers to obtain a spectrum at every single pixel on the part of the sky it targeted, making spectroscopy of an extended object on the sky very efficient. This innovation combined with the stretched and brightened gravitationally lensed galaxy allowed the team to map out the diffuse DLA gas in the sky at high fidelity. Through this method the researchers were able to determine not only the size of the two DLAs, but also that they both contained host galaxies. The DLAs are huge, by the way. With diameters greater than 17.4 kiloparsecs, they're more than two thirds the size of the Milky Way galaxy today. For comparison, 13 billion years ago, a typical galaxy would have a diameter of less than 5 kiloparsecs. A parsec is 3.26 light years, and a kiloparsec is 1,000 parsecs, so it would take light about 56,723 years to travel across each DLA.
NEW MILESTONE IN UNIVERSE'S EXPANSION RATE
NASA/Goddard
Completing a nearly 30-year marathon, NASA's Hubble Space Telescope has calibrated more than 40 "milepost markers" of space and time to help scientists precisely measure the expansion rate of the Universe -- a quest with a plot twist. Pursuit of the Universe's expansion rate began in the 1920s with measurements by astronomers Edwin P. Hubble and Georges Lemaître. In 1998, this led to the discovery of "dark energy," a mysterious repulsive force accelerating the universe's expansion. In recent years, thanks to data from Hubble and other telescopes, astronomers found another twist: a discrepancy between the expansion rate as measured in the local universe compared to independent observations from right after the big bang, which predict a different expansion value. The cause of this discrepancy remains a mystery. But Hubble data, encompassing a variety of cosmic objects that serve as distance markers, support the idea that something weird is going on, possibly involving brand new physics. The new results more than double the prior sample of cosmic distance markers. The team also reanalyzed all of the prior data, with the whole dataset now including over 1,000 Hubble orbits. When NASA conceived of a large space telescope in the 1970s, one of the primary justifications for the expense and extraordinary technical effort was to be able to resolve Cepheids, stars that brighten and dim periodically, seen inside our Milky Way and external galaxies. Cepheids have long been the gold standard of cosmic mile markers since their utility was discovered by astronomer Henrietta Swan Leavitt in 1912. To calculate much greater distances, astronomers use exploding stars called Type Ia supernovae. Combined, these objects built a "cosmic distance ladder" across the universe and are essential to measuring the expansion rate of the universe, called the Hubble constant after Edwin Hubble. That value is critical to estimating the age of the universe and provides a basic test of our understanding of the Universe. Starting right after Hubble's launch in 1990, the first set of observations of Cepheid stars to refine the Hubble constant was undertaken by the HST Key Project that used Cepheids as milepost markers to refine the distance measurement to nearby galaxies. By the early 2000s the teams declared "mission accomplished" by reaching an accuracy of 10 percent for the Hubble constant, 72 plus or minus 8 kilometres per second per megaparsec.
In 2005 and again in 2009, the addition of powerful new cameras onboard the Hubble telescope launched "Generation 2" of the Hubble constant research as teams set out to refine the value to an accuracy of just one percent. This was inaugurated by the SH0ES program. Several teams of astronomers using Hubble, including SH0ES, have converged on a Hubble constant value of 73 plus or minus 1 kilometre per second per megaparsec. While other approaches have been used to investigate the Hubble constant question, different teams have come up with values close to the same number. The team measured 42 of the supernova milepost markers with Hubble. Because they are seen exploding at a rate of about one per year, Hubble has, for all practical purposes, logged as many supernovae as possible for measuring the Universe's expansion. The expansion rate of the Universe was predicted to be slower than what Hubble actually sees. By combining the Standard Cosmological Model of the Universe and measurements by the European Space Agency's Planck mission (which observed the relic cosmic microwave background from 13.8 billion years ago), astronomers predict a lower value for the Hubble constant: 67.5 plus or minus 0.5 kilometres per second per megaparsec, compared to the SH0ES team's estimate of 73. Given the large Hubble sample size, there is only a one-in-a-million chance astronomers are wrong due to an unlucky draw -a common threshold for taking a problem seriously in physics. This finding is untangling what was becoming a nice and tidy picture of the universe's dynamical evolution. Astronomers are at a loss for an explanation of the disconnect between the expansion rate of the local Universe versus the primeval Universe, but the answer might involve additional physics of the Universe. Such confounding findings have made life more exciting for cosmologists. Thirty years ago they started out to measure the Hubble constant to benchmark the Universe, but now it has become something even more interesting.
Bulletin compiled by Clive Down