Daily Archives: July 13, 2023

A supermassive black hole started feasting on surrounding matter resulting in one of the most dramatic "switching on" events ever seen.

Transients are astronomical events or objects that change in brightness over short periods of time, and the one powered by this greedy black hole J221951 is one of the brightest transients ever recorded. The position of the black hole corresponds with the center of a previously observed galaxy, just where a supermassive black hole would be expected to sit. However, astronomers still aren't sure exactly what is causing the transient event witnessed in J221951.

"Our understanding of the different things that supermassive black holes can do has greatly expanded in recent years, with discoveries of stars being torn apart and accreting black holes with hugely variable luminosities," team member and University of Belfast astronomer Matt Nicholl, said in a statement. "J221951 is one of the most extreme examples yet of a black hole taking us by surprise."

Related: Star survives spaghettification by black hole

The nature of what the supermassive black hole located around 10 billion light-years away is consuming is currently unknown, but it is possible that J221951 represents a star that has ventured too close to the black hole being violently ripped apart by tidal forces arising from its immense gravity in a process called spaghettification.

This occurrence, called a tidal disruption event (TDE), would see some of the stellar material from the destroyed star fall to the surface of the black hole while other matter is funneled to the poles of the black hole before being blasted out at near light-speeds, generating intense electromagnetic radiation.

The spaghettification of an unfortunate star isn't the only possible mechanism that could be causing the black hole in question to give rise to this bright transient event, however. Another possibility is that J221951 is the result of the nucleus at the heart of a galaxy switching from a dormant to an active state.

Active galactic nuclei (AGNs) are bright areas at the heart of galaxies that blast out enough light to drown out the combined light of every star in the rest of that galaxy. They are also powered by supermassive black holes.

"Continued monitoring of J221951 to work out the total energy release might allow us to work out whether this is a tidal disruption of a star by a fast-spinning black hole or a new kind of AGN switch on," Nicholl added.

Kilonovas are a type of transient event that occurs during the merger of two neutron stars or a neutron star and a black hole, which releases bright bursts of electromagnetic radiation. Kilonovas initially have a blue coloration, then fade to red over a period of several days. The transient J221951 also appeared blue, but it didn't change to red or fade rapidly as a kilonova would. The nature of this transient was determined by follow-ups with space-based facilities like the Hubble Space Telescope and ground-based observatories like the Very Large Telescope (VLT) located in the Atacama Desert of Northern Chile.

"The key discovery was when the ultraviolet (UV) spectrum from Hubble ruled out a galactic origin. This shows how important it is to maintain a space-based UV spectrograph capability for the future," team member and Mullard Space Science Laboratory at University College London researcher Paul Kuin said.

With a source located 10 billion light-years away, the team realized that J221951 must be one of the brightest events ever seen. They will now work to better understand its cause.

"In the future, we will be able to obtain important clues that help distinguish between the tidal disruption event and active galactic nuclei scenarios," Oates said. "For instance, if J221951 is associated with an AGN turning on, we may expect it to stop fading and to increase again in brightness, while if J221951 is a tidal disruption event, we would expect it to continue to fade.

"We will need to continue to monitor J221951 over the next few months to years to capture its late-time behavior."

The team presented their findings on Tuesday, July 4, at the National Astronomy Meeting 2023 in Cardiff, U.K.

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Hungry black hole 'switches on' as astronomers watch in surprise - Space.com

Nancy Grace Roman (16 May 1925 25 December 2018) not only laid the groundwork for our understanding of how galaxies grow but also founded NASAs space astronomy programme, becoming the mother of Hubble.

Romans love of the stars was evident from an early age, and she set up an astronomy club for her friends when she was just 10.

However, when she told her guidance counsellor she wanted to be a professional astronomer, she was asked, "What lady would take mathematics instead of Latin?"

Ignoring this discouragement, she went on to attain her degree from Swarthmore University before moving to the University of Chicagos Yerkes Observatory for her PhD.

Here she studied the motions of stars which formed in the same cluster as the Plough, but which had drifted apart over time.

Later, Roman expanded this research to all Sun-like stars visible to the naked eye and soon noticed that where stars orbited in the Milky Way was connected to their metallicity.

Metals (meaning anything heavier than helium in astronomy) are only formed inside stars, so if a star contains a lot of metal it must have been born after several generations of previous stars had already produced them.

Younger metal-rich stars tended to move in circular orbits near our Galaxys centre, while older metal-poor stars were further out.

This connection was the first clue towards understanding how the Milky Way grows over time, providing the foundation for modern studies of galactic evolution.

Her work also developed a method of gauging stellar metallicities by comparing their brightness at blue and ultraviolet wavelengths, which is still used today.

Despite these landmark discoveries, Yerkes Observatory refused to grant a woman a permanent position, so in 1954 Roman moved on to the Naval Research Laboratory in Washington DC to work in the emerging field of radio astronomy.

Here, she mapped out the Milky Way in new wavelengths, became head of microwave spectroscopy and consulted on the Vanguard satellite programme.

With radio astronomy still in its infancy, the instrumentation was inadequate for Romans needs, and she didnt want to retrain as an electronics engineer to build her own.

So in 1959 she moved on to the National Aeronautics and Space Administration, NASA, as the head of observational astronomy, just one year after the agency had been established.

This new role effectively brought an end to her research, but with it Roman became the first woman to hold an executive office at NASA, giving her overall responsibility for the growing agencys space-based observatories.

Initially many ground-based astronomers were stubbornly opposed to using remote satellites, but Roman worked tirelessly to convince them of the benefits of observing above Earths atmosphere.

Believing the best way for the US to glean these benefits was for NASA to oversee all major space observatories, Roman was initially the sole voice in deciding which projects would get funded.

Though many of her colleagues advocated for NASA to build a large space telescope, she dismissed the plans as premature, instead electing to fund a series of smaller satellite observatories.

Only in 1968, after a decade of success proved NASAs capability, did Roman return to the idea of a bigger mission, though it took another three years of feasibility studies and funding before she could finally establish the Large Telescope Steering Group.

It would take dozens of institutions 20 years to complete the project, but the telescope launched in 1990, renamed the Hubble Space Telescope.

Although Roman was heavily involved in overseeing the mammoth projects early years, she retired from NASA in 1979 as chief of astronomy, returning occasionally as a consultant.

She continued outreach work as part of her own lifelong mission to champion the inclusion of women in astronomy.

Her vision and many legacies, both scientific and cultural, continue to shape astronomy to this day.

While she may not currently be a household name, Roman will soon be much better-known, as an infrared telescope named in her honour is set to launch in 2027.

The Nancy Grace Roman Space Telescope will have a 2.4m mirror the same size as that of the Hubble Space Telescope but its Wide Field Instrument will have a field of view 100 times that of Hubbles infrared camera.

It will use this huge view to create a 3D map of galaxies, galaxy clusters and distant supernovae to measure how matter is distributed throughout the Universe.

These observations will compliment those by ESAs Euclid mission in the quest to trace dark energy, the mysterious force that appears to be accelerating the expansion of the Universe.

The telescope will even be able to map out otherwise invisible dark matter using a method called microlensing.

When light from a distant galaxy passes another massive object, its path is bent slightly, becoming stretched and distorted.

These distortions can then be analysed to reveal how matter is distributed throughout the cosmos.

Lensing also happens when a planet passes in front of its host star, and the telescope will monitor 100 million stars in the hopes of spotting a stars brightness fluctuating as an exoplanet passes in front.

Most excitingly, this technique should be able to reveal small rocky worlds in habitable orbits, similar to our own Earth.

This article originally appeared in the July 2023 issue of BBC Sky at Night Magazine.

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Life of astronomer Nancy Grace Roman (16 May 1925 25 ... - Sky at Night Magazine

If you're looking for a great pair of binoculars for astronomy, Amazon has got you covered. With impressive 80mm objective lenses and powerful 20x magnification, these SkyMaster binoculars from Celestron are now 55% off in the Prime Day deals, making them just $90.86.

These binoculars are ideal for stargazing, as their large aperture enables exceptional light-gathering capability, resulting in brighter and more detailed celestial views. With their high magnification, you can easily observe the moon's craters, the moons of Jupiter and even some deep-sky objects like star clusters and nebulas. Additionally, their wide field of view allows you to take in the wonders of the night sky and explore constellations with ease. We regularly recommend Celestron's binoculars in our buying guides check out best binoculars, binocular deals, best compact binoculars and best night vision binoculars.

An objective lens cap, rain guard, carrying case, neck strap and lens cloth are all included it also has a tripod adapter, which is particularly useful for extended periods of viewing. We wouldn't necessarily recommend these if you're a total beginner as they have such high magnification which can be tricky to get used to if you're new to the hobby, but if you're looking for your 'next' set of binos or you want to get into astronomy and already have a tripod to keep everything stable, we think they'd be great, especially now that they're such a low price.

But they're also good beyond astronomy, the Celestron Skymaster 20x80 binoculars are also fantastic for terrestrial viewing. They provide stunning clarity and sharpness, making them perfect for wildlife observation, birdwatching and scenic landscape viewing.

Don't forget, if you want to make the most of Amazon Prime Day 2023, check out our Amazon Prime Day hub for a roundup of the best discounts and deals on telescopes, binoculars, cameras, star projectors, drones, lego and much more.

Key Specs:Large multi-coated 80mm objective lenses to let ample light in with 20x magnification for stunning celestial viewing. They're also waterproof, have Bak4 prisms and a comfortable 18mm eye relief, making them good for anyone who wears glasses. They weigh 75oz (2.126kg).

Consensus:For astronomy lovers, we can't recommend these enough, especially for the low price.

Buy if:You're a keen astronomer and want a pair of binos with high magnification for those long nights of stargazing.

Don't buy if:You're a beginner or you want a more 'general' day-to-day pair of binos.

Alternative models: For an even cheaper pair of binos that are more suited to general use (camping trips, sporting events etc) check out the Celestron Outland X 10x42. They're not as beefy and powerful as the SkyMaster, but if that's not what you're looking for, the Outland pair are also on offer for just under $50 for Prime Day. Or if you want even more magnification, the Celestron SkyMaster 25x100 are also 50% off, now sitting at around $250.

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These Celestron SkyMaster binoculars are less than half price in the ... - Space.com

PRESS RELEASE

Published July 11, 2023

[City, Date] -- WhiteStarOutdoors.com, a leading online resource for astronomy enthusiasts, is proud to release its comprehensive guide highlighting the crucial role of amateur astronomers in raising awareness and inspiring interest in the mysteries of the universe.

The focus, of the website, is to encourage and support amateur astronomers worldwide in their efforts to promote astronomy education and exploration.

Amateur astronomers are invaluable in bridging the gap between professional, scientific research and the general public. Through their passion, dedication, and accessible outreach activities, they bring the wonders of the universe closer to people of all ages and backgrounds.

WhiteStarOutdoors.com recognizes and celebrates the immense impact of amateur astronomers in fostering a sense of wonder, scientific curiosity, and lifelong learning about the cosmos.

The guide by WhiteStarOutdoors.com outlines critical strategies and practical tips for amateur astronomers to effectively raise awareness and inspire interest in the mysteries of the universe.

Amateur astronomers play a significant and multifaceted role in the field of astronomy. Their passion, curiosity, and dedication contribute to advancing scientific knowledge, promoting public engagement, and inspiring the next generation of space enthusiasts.

Here are some key aspects that highlight the crucial role of amateur astronomers. It covers a wide range of topics, including:

Observational Research:

Amateur astronomers make valuable contributions to observational astronomy. Equipped with their telescopes and astrophotography equipment, they observe celestial objects, monitor variable stars, track asteroids, and discover comets. These observations provide additional data points for scientific research, complementing the work of professional astronomers and expanding an understanding of the universe.

Public Outreach Events and Education:

One of the most vital roles of amateur astronomers is to inspire and educate the public about astronomy. They organize stargazing events, public lectures, workshops, and star parties, allowing people to observe celestial phenomena firsthand. By sharing their knowledge, explaining complex concepts in accessible language, and answering questions, they ignite curiosity and nurture a sense of wonder about the universe. Suggestions for organizing stargazing events, public lectures, and workshops to engage the local community and ignite curiosity about astronomy.

Online Presence and Social Media:

With the advent of digital platforms, amateur astronomers have a powerful tool to reach a global audience. Many enthusiasts maintain blogs, websites, and social media accounts to share their experiences, astrophotography, and knowledge. Through these online platforms, they can connect with fellow enthusiasts, inspire others to pursue astronomy and contribute to disseminating scientific information. Utilizing social media platforms, blogs, and websites to share knowledge, showcase astrophotography, and connect with a global audience interested in astronomy.

Collaboration with Schools and Institutions:

Collaborative initiatives with schools, colleges, and scientific institutions to provide educational resources, hands-on activities, and mentorship opportunities for aspiring astronomers. Amateur astronomers often collaborate with schools, colleges, and scientific institutions to support astronomy education. They provide resources, conduct workshops, and mentor aspiring astronomers. By sharing their expertise, they contribute to fostering scientific literacy, encouraging young minds to explore the wonders of the universe, and potentially nurturing future professional astronomers.

Citizen Science Projects:

Participating in citizen science initiatives, such as observing variable stars, tracking asteroids, or contributing to light pollution surveys, to contribute valuable data and engage in scientific research. Amateur astronomers actively participate in citizen science projects, contributing to scientific research in collaboration with professional institutions. They engage in activities such as documenting meteor showers, observing transient events like supernovae, or cataloging deep-sky objects. Through their involvement, they contribute to data collection, analysis, and the overall progress of scientific knowledge.

Supporting Amateur Astronomer Communities:

Establishing or joining local astronomy clubs, attending star parties, and organizing group observations to foster community and mutual learning among amateur astronomers.

Advancements in Technology and Innovation:

Amateur astronomers are often early adopters of new technologies and innovations in astronomy. They contribute to developing and refining equipment, software, and techniques used in observational astronomy and astrophotography. Their feedback, experiments, and discoveries have led to advancements benefiting the astronomy community.

Amateur astronomers are vital ambassadors of the universe, bridging the gap between scientific research and the public. Their enthusiasm, knowledge, and commitment help ignite interest in astronomy, foster scientific literacy, and promote a deeper understanding the cosmos. Their contributions are invaluable in shaping a more informed and awe-inspired society.

Amateur astronomers can inspire the next generation of scientists, astronomers, and space enthusiasts. Their efforts catalyze scientific literacy, promote a deeper understanding, and encourage responsible stewardship of the Earth.

For more information and to access the comprehensive guide on the crucial role of amateur astronomers, visit WhiteStarOutdoors.com.

About WhiteStarOutdoors.com:

WhiteStarOutdoors.com is a leading online resource for astronomy enthusiasts, providing informative articles, stargazing tips, equipment reviews, and engaging content related to the mysteries of the universe.

With a mission to inspire and educate, WhiteStarOutdoors.com aims to foster a global community of astronomy enthusiasts, from beginners to advanced observers.

The focus at White Star Outdoors, is understanding astronomers' unique needs and preferences. And, in affiliation with High Point Scientific, their expert team has curated this list to cater to a wide range of budgets and experience levels, ensuring that every stargazer can find a telescope that suits their requirements.

For more information on each telescope, including detailed specifications and pricing, please visit website at https://whitestaroutdoors.com.

White Star Outdoors [emailprotected]

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Amateur Astronomers' Crucial Role in the Scientific Discovery of the ... - Digital Journal

Depictions of the Milky Way show a coiling pattern of spiral arms filled with stars extending outward from the center.

Similar patterns have been observed in the swirling clouds of gas and dust surrounding some young stars planetary systems in the making. These so-called protoplanetary disks, which are the birthplaces of young planets, are of interest to scientists because they offer glimpses into what the solar system may have looked like in its infancy and into how planets may form in general. Scientists have long thought that spiral arms in these disks could be caused by nascent planets, yet none had been detected until now.

In a paper published in Nature Astronomy, University of Arizona researchers report the discovery of a giant exoplanet, dubbed MWC 758c, that may be generating the spiral arms in its infant planetary system. The UArizona astronomers also propose possibilities as to why scientists have struggled to find this planet in the past, as well as how their methods may apply to detecting other concealed planets in similar circumstances.

Our study puts forward a solid piece of evidence that these spiral arms are caused by giant planets, said Kevin Wagner, lead author of the paper and a postdoctoral researcher at the UArizona Steward Observatory. And with the new James Webb Space Telescope, we will be able to further test and support this idea by searching for more planets like MWC 758c.

The planets star is located about 500 light-years away from Earth and is only a few million years old an embryo compared to our own 4.6-billion-year-old sun. Hence, the system still has a protoplanetary disk, as it takes about 10 million years for the circling debris to either be ejected out of the system, ingested by the star, or formed into planets, moons, asteroids and comets. The prominent spiral pattern in this systems debris was first discovered in 2013, and astronomers were quick to point out the connection to theoretical simulations of forming giant planets.

I think of this system as an analogy for how our own solar system would have appeared less than 1% into its lifetime, Wagner said. Jupiter, being a giant planet, also likely interacted with and gravitationally sculpted our own disk billions of years ago, which eventually led to the formation of Earth.

Astronomers have imaged most of the protoplanetary disks in stellar systems that are visible using current telescopes. Out of about 30 identified disks, around one-third feature spiral arms prominent swirls within the gas and dust particles of the disk.

Spiral arms can provide feedback on the planet formation process itself, Wagner said. Our observation of this new planet further supports the idea that giant planets form early on, accreting mass from their birth environment, and then gravitationally alter the subsequent environment for other, smaller planets to form.

Spiral arms are generated due to the orbiting companions gravitational pull on the material orbiting the star. In other words, the presence of a massive companion, such as a giant planet, was expected to trigger the spiral pattern in the disk. However, previous attempts to detect the responsible planet have turned up empty until now.

It was an open question as to why we hadnt seen any of these planets yet, Wagner said. Most models of planet formation suggest that giant planets should be very bright shortly after their formation, and such planets should have already been detected.

The UArizona researchers were finally able to detect MWC 758c by using the Large Binocular Telescope Interferometer, or LBTI, a UArizona-built instrument connecting the telescopes two 8.4-meter primary mirrors that can observe at longer wavelengths in the mid-infrared range, unlike most other instruments used for observing exoplanets at shorter, or bluer, wavelengths. According to Steve Ertel, a co-author on the paper and LBTI lead instrument scientist, the instrument has a camera that can detect infrared light in a similar manner to NASAs James Webb Space Telescope, or JWST.

Even though the exoplanet is estimated to be at least twice the mass of Jupiter, it was invisible to other telescopes because of its unexpected red color the reddest planet ever discovered, Ertel said. Longer, redder wavelengths are more difficult to detect than shorter wavelengths because of the thermal glow of Earths atmosphere and the telescope itself. The LBTI is among the most sensitive infrared telescopes yet constructed and due to its larger size, can even outperform JWST for detecting planets very close to their stars, such as MWC 758c.

We propose two different models for why this planet is brighter at longer wavelengths, Ertel said. Either this is a planet with a colder temperature than expected, or it is a planet thats still hot from its formation, and it happens to be enshrouded by dust.

If there is a lot of dust surrounding this planet, the dust will absorb shorter wavelengths, or bluer light, making the planet appear bright only at longer, redder wavelengths, said co-author Kaitlin Kratter, a UArizona theoretical astrophysicist. In the other scenario of a colder planet surrounded by less dust, the planet is fainter and emits more of its light at longer wavelengths.

Wagner said large amounts of dust in the planets vicinity may tip off that the planet is still forming, and that it might be in the process of generating a system of moons like the Jovian moons around Jupiter. On the flip side, if the planet follows the colder model, there might be something going on in these early stellar systems that causes planets to form colder than expected, prompting planetary scientists to revise their planet formation models and exoplanet detection strategies.

In either case, we now know that we need to start looking for redder protoplanets in these systems that have spiral arms, Wagner said.

The UArizona astronomers anticipate that once they observe the giant exoplanet with the James Webb Space Telescope, they will be able to make a judgement call as to which of the two scenarios is playing out in the infant system. The team has been granted time to use JWST in early 2024 to complete these observations.

Depending on the results that come from the JWST observations, we can begin to apply this newfound knowledge to other stellar systems, Wagner said, and that will allow us to make predictions about where other hidden planets might be lurking and will give us an idea as to what properties we should be looking for in order to detect them.

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Astronomers Discover Elusive Planet Responsible For Spiral Arms ... - Space Ref