Category Archives: Astronomy

The Australian National University (ANU) is seeking to appoint an outstanding Director of the Research School of Astronomy and Astrophysics (RSAA).

RSAA is recognized both nationally and internationally as a leading research institute in astronomy and astrophysics. Itoperates two world-famous observatories and has a long history of research and technical development at the forefront of the field. The Schools mission is to advance the observational and theoretical frontiers of astronomy and astrophysics and their enabling technologies.

Reporting to the Dean of the ANU College of Science, the School Director provides leadership and fosters excellence across the range of the Schools activities including research, educationtechnology development, and external engagement.The appointee will lead the School in the next phase of its evolution, facilitating and promoting a culture of high-performance and collegiality. They will be an effective advocate for the School, and will work collegially with other senior staff of the university to achieve the strategic aims of the College and the University.

The successful candidate will have: an understanding of current issues, challenges and opportunities in research and education in the astronomy and astrophysics disciplines; strong communication skills; the capacity to develop sustainable and productive teams, and relationships with internal and external stakeholders; good judgement and a collegial leadership style that encourages ideas, initiative and research excellence in others. They will havea respectful interpersonal style and high levels of energy, passion and resilience.

The successful candidate will hold a PhD or have equivalent professional experience, and will have an internationally-recognised, academic career in astronomy, astrophysics or a related field. They will haveproven experience in research leadership and in leading an academic school, department or institute and have the capacity to develop and implement a compelling vision and strategy, including innovation in the latest teaching and pedagogy across large scale research and education programs.

For further information and a copy of the information booklet, please contact Kent Vidler, Deputy Manager, ANU Executive Search on +61 408 421 119 or executivesearch@anu.edu.au

Please note advertising closes on Sunday 22 May, 11:55 pm AEST.

ANU values diversity and inclusion and is committed to providing equal employment opportunities to those of all backgrounds and identities. For more information about staff equity at ANU, visithttps://services.anu.edu.au/human-resources/respect-inclusion

The successful candidate will be required to undergo a background check during the recruitment process. An offer of employment is conditional on satisfactory results.

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Director, Research School of Astronomy and Astrophysics job with AUSTRALIAN NATIONAL UNIVERSITY (ANU) | 289685 - Times Higher Education

Markarians Chain is a string of eight galaxies straddling the boundary between Virgo and Coma Berenices. Messier 84 and 86 (farthest right [west]) dominate together with The Eyes, interacting NGC 4435 and 4438, lying to the left (east) of Messier pairing. Image: Terry Hancock.When: all night throughout April.

Whats special: The Virgo Cluster of galaxies reigns supreme for galaxy enthusiasts on spring nights. Its teeming galaxy fields, centred either side of the boundary between Virgo and Coma Berenices, are crammed with any number of outstanding individual galaxy gems, but if youre wanting more bang for your buck, then track down Markarians Chain, a string of galaxies that includes Messier 84 and 86 and the interacting pair NGC 4435 and 4438, popularly called The Eyes.

How to observe: Markarians Chain consists of a line of at least eight galaxies that curves north and east from Messier 84 and 86, just inside Virgo, and extends for about 1.5 degrees to NGC 4477 in Coma Berenices. All of the chain gang should be within range of a 150mm (six-inch) telescope.

Dominant at the western end of the chain are Messier 84 and 86, a pair of ninth-magnitude elliptical galaxies (classed as E1 and E3, respectively) lying around 17 apart. The next two links in the chain, NGC 4435 and 4438 (also catalogued as Arp 120), the interacting starburst pair known as The Eyes, are the most interesting. NGC 4435 is the smaller, more northerly galaxy of the pair, a barred lenticular that, shining at magnitude +10.8, is fainter than NGC 4438, its larger and much-disrupted neighbour (+10.0), though it exhibits a higher surface brightness.

Moving further north and east but staying in Virgo sees NGC 4461, a 4 1 eleventh-magnitude spiral, with NGC 4458, a smaller and round elliptical. The last links in the chain lie across the boundary in Coma. NGC 4473 is a magnitude +10.2 class E5 elliptical spanning 5 3 and, finally, lying around 12 north is magnitude +10.4 NGC 4477, another spiral which covers 4 3.

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Markarian's Chain -the eyes have it! Astronomy Now - Astronomy Now Online

The frustrating quest for dark-matter continues. An unidentified X-ray signature recently observed in a nearby galaxy clusters is not due to the decay of dark matter, researchers report. The findings ruled out previously proposed interpretations of dark matter particle physics. But the near future for solving this great mystery of 21st-century astronomy looks bright.

Despite its cosmological abundance and the well-established astrophysical evidence of its existence, little is known about the mysterious, invisible dark matter particles. Some models of dark matter predict that they might slowly decay into ordinary matter. If so, the process of dark matter decay would produce faint photon emissions detectable by X-ray telescopes.

The Empty-Sky Gamma-Ray Mystery -Evidence of Dark Matter?

Unidentified X-ray Emission Line

Recent X-ray observations of nearby galaxy clusters have detected an unidentified X-ray emission line at 3.5 kiloelectronvolts (keV), which has been interpreted by some as a signature of dark matter decay. Specifically, the X-ray emission was linked to a hypothetical dark matter particle known as a sterile neutrino a theoretical particle that is believed to interact only via gravity and not via other fundamental interactions of the Standard Model. If this is correct, dark matter surrounding our Galaxy should decay and produce a similar X-ray emission line, spread faintly across the entire night sky.

Physicists have suggested that dark matter is a closely related cousin of the neutrino, called the sterile neutrino. Neutrinos subatomic particles with no charge and which rarely interact with matter are released during nuclear reactions taking place inside the sun. They have a tiny amount of mass, but this mass isnt explained by the Standard Model of Particle Physics. Physicists suggest that the sterile neutrino, a hypothetical particle, could account for this mass and also be dark matter.

Searching the Milky Ways Dark-Matter Halo

Christopher Dessert and colleagues searched for the 3.5 keV signal within the ambient halo of the Milky Way using data from the European Space Agencys XMM-Newton space telescope. Everywhere we look, there should be some flux of dark matter from the Milky Way halo, said Nicholas Rodd, currently a particle phenomenologist at CERN, because of our solar systems location in the galaxy. We exploited the fact that we live in a halo of dark matter. Rodds research focuses on the search for dark matter in astrophysical datasets, an approach known as indirect detection.

Dessert, Rodd and colleagues analyzed blank-sky observations (parts of the sky away from large X-ray emitting regions) with a total exposure time of roughly a year, finding no evidence for the predicted 3.5 KeV line. According to the authors, the findings rule out the predicted signal strength by over an order of magnitude.

Is Dark Matter Only the Tip of an Invisible Universe of Unknown Forces?

The Last Word New Technologies will Detect the 3.5 keV Line Far More Accurately

When searching for X-ray photons coming from dark matter, arguably the two most important parameters of your telescope are: 1. How well it can determine the photon energy; and 2. How many photons it collects. It is very challenging to make strides on the second of these, Nicholas Rodd wrote in an email to The Daily Galaxy. We already have instruments like XMM-Newton that have been collecting X-rays for over two decades, giving them a significant head start on any new telescope, he explained.

But technological improvements will allow new instruments to determine X-ray energies far more accurately, Rodd observed in his email. This matters for a potential dark-matter signal like the 3.5 keV line, because as the name suggests, it is expected to be a very narrow line in X-rays. Future instruments including the NASAs X-Ray Imaging and Spectroscopy Mission

(XRISM), due to launch within a year, and in the longer term Advanced Telescope for High-ENergy Astrophysics (Athena) should start to see a very narrow feature coming from dark matter, if thats where the anomaly originates, and play a key role in resolving this dark-matter mystery.

Maxwell Moe, astrophysicist, NASA Einstein Fellow, University of Arizona via Nicholas Rodd, University of Michigan, Science/AAAS, PubMed and ArXiv,org

Image credit: Data gathered by the Hubble Space Telescope creates a map of dark matter.

( NASA/ESA/Caltech)

Maxwell Moe, astrophysicist, NASA Einstein Fellow, University of Arizona. Max can be found two nights a week probing the mysteries of the Universe at the Kitt Peak National Observatory. Max received his Ph.D in astronomy from Harvard University in 2015.

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The Missing Photons Astronomers Hopeful in Search for a Dark Matter Signal - The Daily Galaxy --Great Discoveries Channel

Hundreds of millions of people read their horoscopes every day. Seekers scan the skies for answers to lifes challenges, believing that the planets, and their alignments relative to constellations, have something direct to say to each of us. Many still confuse astrology with astronomy. Even with all my scientific training, I cannot say that I blame them. Would it not be wonderful if the cosmos indeed spoke to us, acting as an oracle? If somehow it could help us find answers for lifes troubles and tribulationsanswers coded in the arrangements of planets and stars?

The better we know the heavens, the better we know ourselves. Even though modern science has stopped seeing the stars as an oracle, we still search for answers in the skies, albeit answers to different questions. As we study the skies scientifically, we are trying to explain our cosmic origins, the beginnings of life on Earthand to know whether we are alone in the vastness of space.

This impulse is as old as civilization. We have been seeking the stars guidance at least since the earliest agricultural gatherings along the Tigris and the Euphrates Rivers, and probably before that. The Babylonians had a serious observational program. They mapped in great detail the motions of planets along the Zodiacthe belt about 8 degrees to either side of the ecliptic, and divided into 12 constellations. For example, the Venus Tablet of Ammisaduqa, dating from about the mid-17th century BCE, recorded the risings and settings of Venus for a period of 21 years. The main goal was astrological. The Babylonians tried to interpret the planets positions as omens for the king.

We have to wonder what inspires this prevalent and constant fascination with the skies. Why, from astrology to astronomy, does it endure?

In ancient times and for many indigenous cultures, the skies were (and still are) sacred. Countless religious narratives and mythical tales from across the planet attest to this. To know the skies was to have some level of control over the course of events that affected people, communities, and kingdoms. The gods wrote their messages on the dark canvas of the night sky, using the celestial luminaries as their ink. The shaman, the priest, the holy man or woman were the interpreters, the decoders. They could translate the will of the gods into a message the people could understand.

Fast forward to the 17th century CE, as Galileo and Kepler were establishing the roots of modern science and astronomy. To them the skies were still sacred, even if in different ways from their predecessors. Theirs was a Christian god, creator of the universe and everything in it. Galileos feud with the Inquisition was not one of the atheist versus the faithful, as it is often depicted. Instead, it was a struggle for power and control over the interpretation of the Scriptures.

The urge to understand the skies, the motions of the planets, and the nature of the stars only grew stronger as science evolved.

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The stars may be way out there, distant and unreachable, yet we feel a deep connection to them. Walking through an open field on a clear, moonless night speaks to us on many different levels. In the modern scientific attempt to study the skies, we identify the same desire for meaning that drove our ancestors to look up and worship the gods. Our most advanced telescopes, such as the Very Large Telescope and the ALMA facility operated by the European Southern Observatory in Chile, or the cluster of amazing telescopes atop Mauna Kea in Hawaii, are testimonies of our modern urge to decipher the heavens. Now we add the spectacular James Webb Space Telescope and its promise to shed some light on many current mysteries of astronomy, including the origin of the first stars when the universe was still very young. We know the answers are there, waiting.

The circle closes when we realize that we ourselves are made of star stuff. The atoms that compose our bodies and everything around us came from stars that died more than five billion years ago. To know thisto know that we can trace our material origins to the cosmosis to link our existence, our individual and collective history, to that of the universe. We have discovered that we are molecular machines made of star stuff that can ponder our origins and destiny. This is the worldview modern science has brought about, and it is nothing short of wonderful. It celebrates and gives meaning to our ancestors urge to decipher the skies. They were looking up to find their origin; we looked up and found it.

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From astrology to astronomy, humans always look to the skies - Big Think

The newest deep space observatory, the James Webb Space Telescope, will give us a deeper view into the infrared universe than the iconic Hubble.

A new video from the European Space Agency (ESA) showcases how Webb will open new vistas into astronomical objects across the universe, ranging from galaxies formed billions of years ago to clouds of gas and dust surrounding newborn stars.

Infrared light is the heat-carrying part of the electromagnetic spectrum with longer wavelengths than visible light. The Hubble Space Telescope is optimized for visible light but can also detect some ultraviolet (shorter wavelengths than visible) and some infrared. Webb, however, was developed as an infrared specialist and can take on a much larger span of infrared wavelengths. That, for example, means seeing even deeper into the universe than Hubble does.

Since the universe is expanding, the galaxies farther away from us are moving away at greater speeds than the closer ones. The light these galaxies emit is shifted into longer, redder, wavelengths, as a result of the Doppler effect (the same effect that distorts the sound of a passing ambulance), also known as redshift in astronomy.

Live updates: NASA's James Webb Space Telescope missionRelated:How the James Webb Space Telescope works in pictures

With better views of the early universe, NASA said in a separate release last year about Webb's infrared capabilities, astronomers hope to gain more insight about how galaxies formed and evolved.

As infrared light is less subject to interference from dust, Webb will also enable astronomers to see what's going on inside of dust clouds in the nearer universe. "We can penetrate the dust and see the processes leading to star and planet formation," ESA said in a statement.

This means that, for example, Hubble's 2020 view of the iconic Eagle Nebula "Pillars of Creation" in infrared could look different with Webb's infrared gaze. The Pillars are a famous zone of star formation, for which Webb may provide more insight.

"Star formation in the local universe takes place in the centers of dense, dusty clouds, obscured from our eyes at normal visible wavelengths," ESA said in the statement.

Peering into objects in the nearer universe will provide additional answers that will further help astronomers build up their understanding of the universe's evolution.

"We really need to understand thelocaluniverse in order to understandallof the universe, Martha Boyer, deputy branch manager of Webb's near-infrared camera (NIRCam), one of the two cameras on board of Webb that will perform the infrared observations, said in the NASA release.

Speaking of the galaxies closest to our own, the Milky Way, Boyer said the so-called 'Local Group' will be a mini-laboratory allowing astronomers to look at galaxies in high definition.

The Local Group consists of three main galaxies, the Milky Way included, which are all located within 5 million light-years from Earth, according to EarthSky. The largest of these galaxies is Andromeda, the Milky Way is the middle one, and a galaxy known as Triangulum is the smallest of the three. The group also includes about 50 dwarf galaxies that mostly orbit the large ones.

Further-away galaxies, Boyer added, "cant resolve much detail, so we dont know exactly whats going on. A major step towards understanding distant or early galaxies is to study this collection of galaxies that are within our reach."

Follow Elizabeth Howell on Twitter@howellspace. Follow uson Twitter@Spacedotcomand onFacebook.

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How the James Webb Space Telescope's infrared detectors will open new vistas in astronomy - Space.com

G C ANUPAMA, president, Astronomical Society of India (ASI), Saturday said India needs more observational facilities and telescopes in order to do competitive research at par with the global community.

She was delivering the presidential address at the 40th ASI meet hosted at IIT-Roorkee and jointly organised with Aryabhatta Research Institute of Observational Sciences (ARIES), Nainital.

India is lagging in observational facilities, thus making us dependent for data on other (global) facilities. This is not a happy situation. India needs to improve the observational facilities and have access to multi-wavelength and multi-messenger facilities, said Anupama. The Giant Metrewave Radio Telescope in Pune, she said, remains among the few world-class facilities available in India. Apart from some telescope facilities working between the 1 metre to 4 metre class, India otherwise does not have telescopes in the optical and infra-red spectra that function in ranges between the 8 metre to 10 metre class for doing competitive science, she said.

According to Anupama, Astronomy, over the recent decades, has grown with a lot of synergy present now in doing science. With Indias participation in the mega science projects like the Thirty Metre Telescope, Laser Interferometer Gravitational Wave Observatory and the Square Kilometre Array projects, a stronger astronomy community was required.

India with a unique longitudinal positioning and places like Ladakh hold promising locations to set up suitable telescopes in future, proposals for which are under consideration, she said. We need to expand also to the submillimetre region the area of star formation. There is a need to upgrade and network the existing telescope facilities with the global ones, especially for studying transient objects, she said.Earlier in the day, the ASI 2022 was formally inaugurated by Professor K Vijay Raghavan, Principal Scientific Adviser to the Government of India. I urge the Indian astronomy community to plan forward-looking and futuristic research plans which will help India make significant contribution in global mega science projects, he said.

In his virtual address, he further elaborated on artificial intelligence (AI) and machine learning (ML) and their growing uses.

Anupama talked about the current areas of research and mentioned that Astronomy was among the top areas included in the Mega Science Vision Document 2035, an effort led by the office of Principal Scientific Advisor. This document will be a roadmap for deciding future course of research covering nuclear science, high energy physics, astronomy and astrophysics, accelerator-based science and technology and climate research, ecology and environment.

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India needs more world-class telescopes to do competitive research in Astronomy: Anupama - The Indian Express

April 8 Star Gaze with Oakland Astronomy Club in Oakland Twp.

April 8 Star Gaze with Oakland Astronomy Club in Oakland Twp.

Share safe telescopic views of the Winter night sky with the Oakland Astronomy Club. See details of lunar craters and the colorful gases of the star nursery in Orion. Find the Big Dipper and Leo the Lion and enjoy the colorful stars of the Winter sky before they disappear for the season!

April 8th, 8-9:30 for adults to teens, at Marsh View Park,3100 E Clarkston Rd, Oakland, MI 48363. Register online at: https://oaklandtownship.recdesk.com/Community/Program/Detail?programId=677

April 9th, 8-9:30 for star gazers of all ages, at Independence Oaks County Park, 501 Sashabaw Rd., Clarkston, MI 48348. Register via phone with Oakland County Parks during weekday business hours at248-858-0916.

More info: http://oaklandastronomy.net/event.html

For more things to do, visit the Oakland County Times Event Page! To submit event info email editor@oc115.com .

Thank you to Jim Shaffer & Associates Realtors for sponsoring this section!

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April 8 Star Gaze with Oakland Astronomy Club in Oakland Twp. Oakland County Times - Oakland County Times

Basic structure of our home galaxy, edge-on view. The new results from ESA's Gaia mission provide for a reconstruction of the history of the Milky Way, in particular of the evolution of the so-called thick disc. (Stefan Payne-Wardenaar / MPIA via ESA)

Scientists have discovered that parts of the Milky Way galaxy are actually older than previously thought at least by two billion years.

Data collected by the European Space Agencys (ESA) Gaia mission was analyzed by astronomers from the Max-Planck Institute for Astronomy in Heidelberg, Germany, and compared to earlier datasets from Gaias observation of the motion of stars in the outskirts of our galaxy, also known as the anticentre, in 2020.

In addition, astronomers received data from Chinas Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) for roughly 250,000 stars to derive their ages, according to an agency news release.

Combining this information, astronomers were able to determine that stars within the "thick disc" part of our galaxy began forming 13 billion years ago, around 2 billion years earlier than expected, and just 0.8 billion years after the Big Bang, according to the ESA.

So, our beautiful galaxy is made up of billions of components, but to keep things simple, well narrow it down to the disc and the halo.

If one were to hypothetically look at our galaxy and it laid flat, you would be able to see a bulge in the center of the disc, which is essentially the center of our galaxy.

Surrounding that disc is the stellar halo, which is the outermost part of our galaxy and was originally believed to be the oldest part of the Milky Way, the ESA said.

The halo has a radius of about 100,000 light-years and contains isolated stars as well as many globular clusters, which are basically clusters of millions of stars packed into one area.

The galactic disc is made up of both thick and thin discs. The thin disc, which is about 700 light-years high in comparison to the galactic disc, contains most of the stars we humans can see. Its often photographed as a misty streak across the night sky and dotted with stars.

The thick disc, which is about 3,000 light-years high, contains fewer stars but this is the area where astronomers were able to find their surprising discovery, thanks to Gaia, according to the ESA.

An artists impression of our Milky Way galaxy, a roughly 13 billon-year-old barred spiral galaxy that is home to a few hundred billion stars. (NASA/JPL-Caltech; right: ESA; layout: ESA/ATG medialab)

Determining a stars age is one of the most difficult things to decipher, according to the ESA.

"It cannot be measured directly but must be inferred by comparing a stars characteristics with computer models of stellar evolution. The compositional data helps with this," according to the ESA.

Astronomers must take into account the matter of which a star is made in its early stages which includes hydrogen and helium. Once a star is born, it will continue to develop and create metals within itself. These metals are expelled out into space as a star grows older, according to the ESA.

So, to make a very complicated method easy to understand: The fewer metals a star has, the older it is.

"Together, the brightness and metallicity allow astronomers to extract the stars age from the computer models," the ESA said.

The Milky Way was formed in two phases, according to the ESA.

The first phase was the Big Bang which happened around 0.8 billion years ago, scientists believe.

The aforementioned "thick disk" began to form at this time. Astronomers also believe other parts of the galaxy, such as the inner parts of the stellar halo which basically encircles the entirety of the Milky Way galaxy, began to form as well.

Then, the Gaia-Sausage-Enceladus, which was a dwarf galaxy hurtling through space, collided with the Milky Way and rapidly accelerated the formation of our galaxy, according to Carnegie Mellon University.

This collision gave birth to millions of stars, according to the ESA.

During the second phase of the galaxys formation, a thinner disc developed as all of the space matter began to form together and thats when Earths sun and subsequent planets were formed.

This story was reported out of Los Angeles.

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Parts of Milky Way are older than expected, astronomers say - FOX 6 Milwaukee

Growing up, Jesse Stout remembers learning about astronomy from his dad.

"When I was younger my father used to take us out camping and that was probably the first time I was introduced to astronomy," he said.

"We used to look up at the stars and my father used to point out things I'm not too sure how accurate he was."

But a life-changing workplace accident in 2018 saw him rethink how he saw himself, and rediscover an old interest.

"A lot of my hobbies before my accident were very, very active, so camping, going to the beach or surfing," he said.

"The ASV has allowed me to explore my new hobby and be positive about a new element in my life I think that's a very, very hard thing to express when you've got a disability."

Late last year, as he recovered from a second surgery on his back, Jesse's partner and family decided to pool their money to buy him a telescope.

Excited to try it out, Jesse soon discovered having to manoeuvre himself around the equipment came with a very painful drawback, that could leave him in pain for days afterwards.

Looking around for groups to join, he found the Astronomical Society of Victoria's (ASV) Pathways to the Planets project, trying to raise funds to make their sites and equipment more accessible for people with varying levels of mobility.

With around 12 per cent of its members having some sort of disability, ASV Vice president Mark Iscaro said it was stories like Jesse's that inspired them.

"The sky belongs to everyone," he said.

"If there are people who've got sight issues, they should still be able to feel the night sky, whether that's through 3D-printed star maps, and those with mobility issues shouldn't be prevented from coming up and seeing the stars."

Now, in the year of their 100th anniversary, the society has opened an all-abilities accessible observatory at the Leon Mow dark sky site near Heathcote, north of Melbourne, with features such as better-lit and widened pathways, a motorised entry gate and accommodation for those staying overnight.

There are also plans to build remote-controlled astrophotography observatories for people who can't physically travel to the site, or use an eyepiece.

The main attraction is a specially designed telescope, altered to make the eyepiece the axis so it stays at the perfect height for a viewer sitting down.

ASV President Chris Rudge said traditional astronomical equipment wasn't always easy for everyone to use.

"Unfortunately, to use those large telescopes you have to go up a ladder, but this new telescope we've specially built so that you can sit down and look at the night sky," he said.

"We have many older members these days, including myself, who may be mobility-limited, they can just sit down and enjoy the night sky at their leisure."

The telescope is the second in Victoria, with the first being in the regional town of Ballarat.

But the ASV is hoping their larger member base and more widely accessible facilities will attract more keen astronomers in the future.

Jesse was just looking forward to enjoying his hobby pain-free.

"I'll be able to use the telescope and I'll be able to look at the stars and not have to worry about the next day that I'm going to be bedridden because of the pain from bending down or moving around or adjusting my body slightly," he said.

And it has reminded him of what he loves about looking up at the skies.

"There's a huge element of mystery behind astronomy," he said.

"Being able to look up into the sky and realising you're finding something new each time you look and the fact that a telescope can bring you even closer to finding something."

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A new all-abilities accessible observatory in Heathcote is opening up new worlds for Victorians - ABC News

The Sun is literally the closest star to us in the entire Universe, but theres a lot about it thats still pretty mysterious.

For example, nearly 150 years ago, the astronomer Angelo Secchi first observed narrow, towering fingers of material stretching vertically away from the Sun. Called spicules, these can grow to a height of 12,000 kilometers nearly the diameter of the Earth but tend to be only 1/10th that wide. They grow in a matter of minutes, shooting upwards at tens of thousands of kilometers per hour, then collapse back down.

There are millions of spicules on the Sun at any given moment, and they look like grass or shag carpeting. Time-lapse video of them is entrancing and eerie:

And while theyre known to be associated with strong magnetic fields typical of phenomena on the Sun even after all this time its not clear what causes them. Paper after paper has been published over the years, with varying degrees of success in explaining these weird features.

A few years ago, a study showed that they may be due to the way the magnetic field interacts with both electrically neutral and charged particles on the Suns surface. However, a different team of solar astronomers wondered if there might be a more fundamental piece of physics going on with them. They noticed how fluids can dance when vibrated by the sound waves from a speaker heres a good video of that and thought there might be a connection. When the surface of a fluid is vibrated you can get neat patterns in it as waves get pumped up by them, but as the frequency gets higher theres a critical frequency when the surface starts to create jets of water shooting up. This type of motion is called Faraday excitation or Faraday waves. Usually in water or other liquids the top of the jet breaks off into a droplet that then falls back to the surface.

This type of event is common in nature; in fact alligators use a low-frequency mating call that can cause it to happen in the water around them, shown in this video about 20 seconds in.

The Suns surface is a plasma, mostly hydrogen thats so hot the atoms have lost an electron, and is dense enough to act like a fluid. Also, there are plenty of sources of vibrations in the solar surface. Deep inside the Sun theres a layer where extremely hot material rises buoyantly, and when it gets to the surface it cools and falls back down. This is called convection, and there are many towering convective conveyor belts transporting material up and down in the Sun. This causes a continuous rumble on the surface at a frequency that could excite Faraday waves.

The new research [link to paper] first shows that the physics of Faraday waves in the Sun and in a fluid dancing on a speaker are similar. They then experimented in the lab with various fluids to see if they could mimic spicules. They found that a diluted mixture of a polymer (specifically polyethylene oxide) when placed over a speaker can create jets very similar to spicules, and when diluted at the right amount the droplet creation is suppressed as well. Spicules dont make droplets, so given that the math is similar to describe both effects, there could be some physical similarities.

They then turned to software that simulates the behavior of the solar plasma. Using the known physics of how it behaves, the code can be tweaked to see if certain behaviors can be reproduced. Without any real detailed inputs just using the vibrations of the solar surface created from sound waves of certain harmonic frequencies their code reproduced spicule-like structures. Thats encouraging! They also found the driving frequency doesnt need to be harmonic (that is, sound waves of evenly divisible frequencies, like say 440 and 220 and 110 Hertz), but can be quasi-periodic; mostly periodic but with some randomness thrown in. Thats good too, as the Suns surface is a cacophony of different frequencies that dont always create harmonic chords.

When they added a simple vertical magnetic field to their code they found they got even more spicule-like behavior, with about the right heights and widths. The speed of growth was similar, too. The magnetic field introduces an anisotropy, a non-symmetric nature to the surface that helps squeeze the plasma into narrow towers. This is similar for the need of the polymeric fluid to be diluted; that also is an anisotropy that helps the jets form.

The overall conclusion is that they found a more fundamental reason spicules might be produced on the Sun without the need for lots of special circumstances. This doesnt mean earlier research was wrong, necessarily, but it can be nice to reach for more basic physics sometimes to see what it contributes, and then add layers to it.

And, like the earlier attempts to explain spicules, its hard to know if this is the right answer. Just because the experiments and code make something that looks like spicules doesnt mean thats whats going on.

As I like to point out, this is the nature of science. We usually wind up with lots of ideas to explain a phenomenon, and it can take a while to weed out which ones are actually involved and which arent. The Sun is a nightmare of complexity, and a lot of its behavior is incredibly difficult to understand. But we now have observatories like Hinode and Solar Dynamics Observatory and the Inouye Solar Telescope that can see the Sun in high resolution and at wavelengths of light our eyes cant see, and all these observations help the theorists figure out whats what.

As time goes on, well understand the Sun better and better. That too is how science works.

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Bad Astronomy | Spicules on the Sun may be due to Faraday waves | SYFY WIRE - Syfy