Daily Archives: September 8, 2021

The Subaru Telescope, an 8.2-meter diameter optical and infrared telescope located in Hawai`i, is the flagship facility of Japanese astronomy. Since 2000, an ever-evolving instrument suite keeps the Subaru Telescope on the cutting edge of science. It has been used by over 17,000 researchers to produce high-quality results including 156 PhD theses. In terms of citations, 16% of scientific papers using the Subaru Telescope rank in the top 10% of papers; and over 3% of Subaru Telescope papers rank in the top 1%.

In the coming decades, results from extremely large telescopes will change the way we think about humanitys relationship to the Universe. But as organisations around the world race to build larger telescopes, they face a trade-off. Larger telescopes have innately smaller fields of view, meaning the portion of the sky that can be captured in one observation. Simply put, extremely large telescopes will see an extremely small area extremely well. But without a comprehensive and accurate map of potential targets, these enormous telescopes will spend all their time staring at empty space, hoping for something interesting. Figuring out where to point a telescope to do the best research can be a difficult question.

The Subaru Telescope is and will continue to be the best telescope in the world for creating maps to guide future extremely large telescopes. Utilising a unique four foci design, the Subaru Telescope is able to side-step the size vs. field-of-view trade-off, achieving by far the largest field of view of any 8-metre class telescope. To make the best use of this advantage, we developed Hyper Suprime-Cam (HSC), one of the worlds largest digital cameras (shown in photo). HSC uses 870 megapixels to capture an area nine times the size of the full moon. This wide field of view is important to create cosmic maps.

The Subaru Telescopes wide field of view and high sensitivity also provides an unparalleled advantage for quickly finding the optical counterpart of gravitational wave or neutrino burst events, which involve instantaneous releases of unimaginable amounts of energy. The progenitors of these events evolve quickly after the outburst, but they are difficult to locate exactly for further study. The Subaru Telescope can cast a wide net to find them before they change too much. This is the paradigm of the emerging field of multi-messenger astronomy: observations of the same event in electromagnetic waves, ranging from radio to gamma rays, are combined with observations of non-electro-magnetic messengers such as gravitational waves or neutrinos to build a comprehensive picture of the Universe.

Soon, the Rubin Observatory Simonyi Survey Telescope will start observations with a field of view even wider than the Subaru Telescope. However, the Subaru Telescope will continue to offer observational capabilities not available at Rubin Observatory. Most notably, the Prime Focus Spectrograph (PFS) can simultaneously observe up to 2400 astronomical targets across a field of view comparable to that of HSC. PFS observes spectra allowing astronomers to determine crucial information about an objects speed, distance, and chemical composition. Therefore, Rubin Observatory will be our synergetic collaborator.

In the coming decades, extremely large 30-metre class telescopes will revolutionise how we think about the Universe and humanitys place in it. At the National Astronomical Observatory of Japan (NAOJ) we are participating in the TMT (the Thirty Meter Telescope) project, along with the California Institute of Technology, the University of California, the National Astronomical Observatories of the Chinese Academy of Sciences, the Department of Science and Technology of India, and the National Research Council (Canada). Larger telescopes can see fainter objects, more distant objects, and finer details. Therefore, TMT will be an ideal facility to follow up on interesting objects found by the Subaru Telescope.

Twenty-first-century astronomy is founded on collaboration. There is collaboration across political boundaries to construct large-scale facilities like TMT. There is also a collaboration between research facilities and collaboration across the traditional boundaries between research fields.

The Universe is a marvellous science laboratory filled with naturally occurring phenomena that are impossible to reproduce on Earth. For example, we still have little direct observational data about dark matter and dark energy which dominate the Universe. To unlock the mysteries of the Universe, the Subaru Telescope is stimulating cross-disciplinary work combining astronomy, general relativity, life sciences, and informatics involving big data and Artificial Intelligence.

The Subaru Telescope has long collaborated with neighbouring facilities in Hawai`i like W.M. Keck Observatory and Gemini North. Going forward, the Subaru Telescope will engage in synergetic collaboration with diverse partners such as Rubin Observatory, TMT, and multi-messenger facilities. Looking to the space-based astronomy community, the Subaru Telescope has initiated collaboration with NASAs Nancy Grace Roman Space Telescope and ESAs Euclid space telescope.

These collaborations on the ground and with space go beyond simple coordinated observations and data exchange. It starts much earlier, in the planning stages, deciding what instruments to build, what programs to conduct, and setting the overall direction for world astronomy in the coming decades.

It is fitting that the Subaru Telescope, which is charting the course for us to explore the heavens, is located in Hawai`i, where Native Hawaiians have long practised wayfinding, the art of guiding double-hulled sailing canoes by the stars and other natural signs. As modern explorers, we are inspired by the courage and ingenuity of those early navigators. In addition to the Subaru Telescope being an active and respected member of the world scientific community, it is also a member of the local community. We place great value on maintaining an environment of mutual trust and respect with our neighbours.

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Subaru Telescope: A nexus of next generation astronomy collaboration - Open Access Government

Scientists have uncovered evidence that white dwarf stars - previously believed to be inert - may in fact simply be ageing much more slowly by burning hydrogen on their surface, challenging a major technique astronomers use to determine stellar ages.

Although the prevalent view of these stars is that they have burnt up their hydrogen, new research contradicts that assumption.

Observations by the Hubble Space Telescope suggests that white dwarfs can continue to undergo stable thermonuclear activity, according to the new paper published in Nature Astronomy.

Jianxing Chen, of the University of Bologna and the Italian National Institute for Astrophysics, who led the research, said: "We have found the first observational evidence that white dwarfs can still undergo stable thermonuclear activity. This was quite a surprise, as it is at odds with what is commonly believed."

Because white dwarf stars are some of the oldest stellar objects in the universe, they offer scientists a good way to estimate the age of neighbouring stars.

But the new discovery could prompt a reassessment of how old some of the stars in the Milky Way are, as it means the cooling rate of a white dwarf is not necessarily the infallible clock it was once assumed to be.

At their core these stars are solid and made of oxygen and carbon due to what is called a phase transition - similar to water turning into ice, only at much higher temperatures.

Scientists have directly observed evidence of white dwarfs cooling into giant crystals.

Researchers at the University of Warwick believe our skies are filled with these enormous crystals, according to observations made with the European Space Agency's Gaia satellite.

Roughly 98% of all of the universe's stars will complete their lifecycles as white dwarfs, including our own sun, while more massive stars will collapse into neutron stars and black holes.

Astronomers have now compared cooling white dwarfs in two massive collections of stars - the globular clusters M3 and M13 - using the Hubble Space Telescope.

Analysing these clusters at near-ultraviolet wavelengths, the team compared more than 700 white dwarfs and found M3 contained standard white dwarfs which are simply cooling stellar cores.

But they found that M13 contains two populations of white dwarfs.

One population is of standard white dwarfs but another group which has somehow managed to hold on to an outer envelope of hydrogen, meaning they burn for longer and cool more slowly.

The researchers compared their results with computer simulations and found that roughly 70% of the white dwarfs in M13 were burning hydrogen in these envelopes on their surfaces.

Francesco Ferraro, also of the University of Bologna and the Italian National Institute for Astrophysics, aid: "Our discovery challenges the definition of white dwarfs as we consider a new perspective on the way in which stars get old.

"We are now investigating other clusters similar to M13 to further constrain the conditions which drive stars to maintain the thin hydrogen envelope which allows them to age slowly."

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White dwarf stars are meant to be dead - but astronomers have just found some that are still alive - Sky News

Department of Physics

Grade 5: - 22,847 - 26,341 per annumFixed Term - Part TimeContract Duration: 24 monthContracted Hours per Week: 17.5Closing Date: 18-Sep-2021, 6:59:00 AM

The Department and role purpose

The Department of Physics at Durham University is one of the very best UK Physics departments with an outstanding reputation for excellence in teaching, research and employability of our students.

The Department of Physics is committed to building and maintaining a diverse and inclusive environment. It is pledged to the Athena SWAN charter, where we hold a silver award, and has the status of IoP Juno Champion. We embrace equality and particularly welcome applications from women, black and minority ethnic candidates, and members of other groups that are under-represented in physics. Durham University provides a range of benefits including pension, flexible and/or part time working hours, shared parental leave policy and childcare provision

The Astronomy research group are seeking to appoint a self-motivated and experienced Project Coordinator to provide a professional service in support of the Astrophysical Constraints On The Identity Of The Dark Matter project and to support the daily operations and the effective and efficient running of the research section.

The post holder will be a committed, enthusiastic professional who relates well to people at all levels. She/he will be expected to demonstrate a high level of initiative and be confident in dealing with diverse groups, including visiting researchers, Heads of Faculties, Departments and Colleges and research groups across the University.

The post holder will be expected to work flexibly to deliver effective administrative support and guidance to the Project, relevant Astronomy group staff and its stakeholders. Working closely with senior staff and colleagues, she/he will be required to assist with the fundamental and general Astronomy group administrative services, as well as assisting with data gathering for funding and project applications, organising events and research activities, creating and maintaining financial and publishing records. The role will also provide opportunities for the post holder to contribute to the development of new promotional materials and communication tools for the Astronomy group e.g. website and social media content.

The Astrophysical Constraints On The Identity Of The Dark Matter Project Coordinator will act as the first point of contact for enquiries and managing a wide range of internal and external enquiries from staff, partners and other stakeholders via email, telephone and face-to-face contact, taking an active decision-making role and using judgement on a day-to-day basis, providing advice, support and information.

The candidate would be expected to assist the Principal Investigator and other members of the Astronomy Senior Management Team, providing administrative support to ensure the smooth running of activities and to maximise effective use of academic staff time.

This role is an excellent opportunity for an administrator seeking to develop their experience and knowledge at both strategic and operational levels, and applications are invited from enthusiastic individuals looking to embrace a new challenge.

Core responsibilities:

Role responsibilities:

Person specification - skills, knowledge, qualifications and experience required

Criteria:E, D

Recruiting to this post

In order to be considered for interview, candidates must evidence each of the essential criteria required for the role in the person specification above (including those listed in the section Realising Your Potential Approach).

In some cases, the recruiting panel may also consider the desirable criteria, so we recommend you evidence all criteria in your application.

Please note that some criteria will only be considered at interview stage.

How to apply

We prefer to receive applications online.

Please note that in submitting your application Durham University will be processing your data. We would ask you to consider the relevant University Privacy Statement https://www.dur.ac.uk/ig/dp/privacy/pnjobapplicants/ which provides information on the collation, storing and use of data.

What you are required to submit

Please ensure that you submit all documentation listed above or your application cannot proceed to the next stage.

Contact details

For further information please contact; Linda Wilkinson, Research Manager l.a.wilkinson@durham.ac.uk

DBS Requirement:Not Applicable.

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Astronomy Project Coordinator job with DURHAM UNIVERSITY | 264788 - Times Higher Education (THE)

Stellar nurseries are made up of molecular clouds of dust and gas where star formation occurs. Astronomers need to study how stars are born to understand the mechanisms behind the universe. Now, an astronomer and artist used 3D printing to allow scientists to hold stellar nurses in their hands.

According to Phys.org, astronomy assistant professor, Nia Imara from UC Santa Cruz created the resin globes using data acquired from these star-forming regions to reveal features in unparalleled detail that are often unseen in the usual renderings and animations of stellar nurseries.

(Photo: Wikimedia Commons)This shot from the NASA/ESA Hubble Space Telescope shows a maelstrom of glowing gas and dark dust within one of the Milky Ways satellite galaxies, the Large Magellanic Cloud (LMC). This stormy scene shows a stellar nursery known as N159, an HII region over 150 light-years across. N159 contains many hot young stars.

Imara, an astrophysicist and artist, and her collaborators used a sophisticated 3D printing process to create the resin globes that show fine-scale densities and gradients of turbulent clouds of dust and clouds as described in simulations of star-forming regions.

These 3D-printed stellar nurseries are highly polished spheres that are 8 centimeters in diameter. Imara said that this interactive object would help astronomers visualize structures where star formation occurs to better understand their physical processes.

Imara told UC Santa Cruz News Centerthat she got an idea from a sketch she made a few years back wherein she was holding a star. As someone who specializes in star formation within molecular clouds, it somehow occurred to her that she could build a 3D model of stellar nurseries using data from simulations of these star-forming regions.

Imara said that the 3D-printed stellar nurseries are an example of science imitating art. They were both visually striking and scientifically illuminating that astronomers begin to notice complex structures that are often obscured when using the usual techniques for visualizing simulations of stellar nurseries.

For instance, the spheres helped them to better see structures that are hard to distinguish in 2D slices or projections. Also, they reveal features that are more continuous than they would appear when presented in 2D projections.

"If you have something winding around through space, you might not realize that two regions are connected by the same structure, so having an interactive object you can rotate in your hand allows us to detect these continuities more easily," Imara said in the news release.

She described the 3D-printed stellar nurseries in her study, titled "Touching the Stars: Using High-Resolution 3D Printing to Visualize Stellar Nurseries," published in The Astrophysical Journal Letters.

ALSO READ: Stars Gobble Up Planets; Instability of Solar Systems Could Help Identify Sun-Like Stars Hosting Earth-like Planets

Orion Nebula is a famous region in the universe where stars were born. According to NASA, turbulence deep within these clouds of dust and gas gives rise to knots with enough mass for it to collapse on its gravitational pull. As these clouds collapse, the protostar within them begins to heat up to become a star someday.

Scientists have used 3D computer models before to predict that spinning clouds of dust and gas could break up into two to three blobs, which explains why many stars in the Milky Way are paired or in groups.

But not all of the pieces of the gathering dust and clouds become a star. Some become part of asteroids, planets, and comets, or sometimes they remain as dust clouds.

RELATED ARTICLE: Where Stars Are Born: NASA's SOFIA Telescope Captures High-Resolution View of a Star Nursery in the Milky Way

Check out more news and information on Starson Science Times.

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3D Printing Allows Astronomers to Hold Stellar Nurseries in Their Hands to Observe the Stars - Science Times

A multinational team of astronomers has discovered what happens when a large star accidentally eats a black hole or neutron star: it emits a catastrophically violent, galactic-scale burp that can be detected from over 450 million light years away.

Stellar boffins have previously theorised what would happen in this situation, but now a group based variously in the US, Israel, Canada and Japan have published a paper in the journal Science [behind paywall] and on Arxiv, which explains how they managed to observe the phenomenon using detective work and information from a number of different instruments and arrays.

The story starts, like Star Wars, long, long ago, in a small, star-forming galaxy far, far away (some 480 million light years). In this case, featuring an object with the catchy name of VT 1210+4956 on the galactic outskirts. The scientists learned from data from a study called the Very Large Array Star Survey (VLASS) that it had started pumping out huge amounts of radio waves, but had not been in another earlier survey using the same telescope array.

Further investigations revealed that an instrument called MAXI (Monitor of All-sky X-ray Image) on board the International Space Station had detected a massive burst of X-rays coming from the same object back in 2014. This burst had lasted just 15 seconds, but during that time its energy emissions had been 10 trillion times greater than those of the Sun.

This was a not-insignificant event.

The astonished astro-whitecoats worked out that the only process which could have created this sequence was a merger-triggered core collapse supernova, aka the stellar cannibalism incident mentioned earlier.

This process can come about because massive stars capable of ending their lives in a supernova are often created in pairs called binary systems, which orbit around each other. In a binary system, one of the stars will inevitably be larger than the other because the universe or at least, our part of it is an imperfect place.

Because both stars are very large, their immense mass will make them burn very hot and their lifespans in galactic terms will be comparatively short. Of the two stars, the larger one will burn hotter and use up its nuclear fuel faster, before swelling into a supergiant star and eventually exploding in a supernova. In the case of a merger, things then get very weird.

The remains of the first star, without the nuclear processes required to counteract the immense gravity its mass creates, will collapse into an ultra-dense neutron star or the gravitational singularity of a black hole, phenomena collectively known as compact objects.

We are now left with a massive star approaching the end of its lifespan orbited by a much smaller, but still gravitationally immense, compact object. When the second star swells up into a supergiant, it finds a compact object already there: in fact, the supergiant may increase in size to such an extent that it expands past the orbit of the compact object and the smaller body ends up inside the larger one. What then follows is the worst case of indigestion in the galaxy.

The compact object starts sucking in material from the star's outer layers, while at the same time the interaction of the compact object's orbit and the rotation of the star flings massive quantities of it out into space in a huge spiral of gas.

This process continues for a few hundred years, with the compact object moving deeper and deeper beneath the star's surface, throwing off spiralling streams of gas all the way, until it finally reaches the core.

At this point the interaction between the two binary partners, which has been very energetic but seems oddly sedate in human terms centuries are not a denomination of time that are often used in reference to stars suddenly becomes very explosive indeed.

Material from the star's core interacts with the intruder, creating a superhot disk of material expanding outwards and immense jets of energy and matter blasting out perpendicular to the disk at close to the speed of light. These emissions collide with slower-moving matter around the star with incredible energy, creating a blast of X-rays that you can see from 480 million light years away.

"That jet is what produced the X-rays seen by the MAXI instrument aboard the International Space Station, and this confirms the date of this event in 2014," said Dillon Dong, a graduate student at Caltech and lead author on a paper in an interview with the National Radio Astronomy Observatory.

While this is happening, the intrusion of the compact object into the star's core causes it to explode in a supernova almost instantly. The material from that explosion is also ejected outwards at great speed and after a few years it catches up with gases ejected earlier and slams into them.

"The companion star was going to explode eventually, but this merger accelerated the process," Dong added.

This creates a further burst of radio waves that you can also see from 480 million light years away.

The ultimate result of all this interstellar argy-bargy is a pair of compact objects black holes, neutron stars, or one of each orbiting around each other as before, surrounded by an expanding cloud of very brightly shining gas.

A salutary tale which proves that cannibalism is very bad for you and gives you terrible, brightly shining gas which can be seen from 480 million light years away.

"Of all the things we thought we would discover with VLASS," said Gregg Hallinan of Caltech, one of the paper's co-authors, "this was not one of them."

Well, you wouldn't. But it turns out the galaxy is a cruel, unforgiving and surprisingly windy place.

Originally posted here:

Astronomers detect burps of interstellar cannibal from 480 million light years away - The Register

A recent study examined the origin of ultra-diffuse dwarf galaxies (UDGs), a rare type of galaxies containing a small number of stars that are spread out over large regions in space, and have an extremely low surface brightness, making them highly difficult to detect.

Using sophisticated computer simulations, scientists detected a few quenched UDGs (ultra-diffuse galaxies that have stopped producing stars) in low-density environments in the universe.

What we have detected is at odds with theories of galaxy formation since quenched dwarfs are required to be in clusters or group environments in order to get their gas removed and stop forming stars, said co-author Laura Sales, an associate professor ofPhysics and Astronomy at the University of California, Riverside.

But the quenched UDGs we detected are isolated. We were able to identify a few of these quenched UDGs in the field and trace their evolution backward in time to show they originated in backsplash orbits.

According to Professor Sales, a backsplash galaxy looks like an isolated galaxy in the present, but in the past was a satellite of a more massive system. Isolated galaxies and satellite galaxies have different properties because the physics of their evolution is quite different, she explained. These backsplash galaxies are intriguing because they share properties with the population of satellites in the system to which they once belonged, but today they are observed to be isolated from the system.

Scientists believe that in the past, quenched UDGs coalesced within halos of dark matter with unusually high angular momentum. Similar to a cotton candy machine, such an extreme environment might have spun out dwarf galaxies that were unusually stretched out. Although they evolved within galaxy clusters, at a certain moment in the past, interactions within the cluster most probably ejected the UDGs into the void, giving them wide, boomerang-like trajectories (the so-called backsplash orbits). During this process, the UDGs gas was stripped away, leaving them unable to produce stars (quenched).

These orbits are almost like those of comets in our solar system, said Professor Sales. Some go out and orbit back around, and others may come in once and then never again. For quenched UDGs, because their orbits are so elliptical, they havent had time to come back, even over the entire age of the universe. They are still out there in the field.

The research is published in the journal Nature Astronomy.

By Andrei Ionescu, Earth.com Staff Writer

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Astronomers explain the origin of isolated ultra-diffuse galaxies - Earth.com