Astronomy and Planetary Science Thread

[Flyaway]

View: https://youtu.be/Mfo8ReC9IPI

 

[publiusr]

To harness that power…

 

[Flyaway]

Space agency NASA has announced that the number of known exoplanets—planets that orbit a star other than our Sun—has passed the 5,000 mark.

The latest batch, a haul of 65 “new” exoplanets that includes a red dwarf star with five orbiting planets, has been added to the NASA Exoplanet Archive.

However, scientists at the Massachusetts Institute of Technology (MIT) has discovered that three—and possibly four—of the exoplanets included in the archive are, in fact, just stars.

However, there are doubts even about some confirmed exoplanets. A new paper published in the Astronomical Journal contains evidence against the very existence of four exoplanets.

Originally discovered by NASA’s Kepler Space Telescope—a missions from 2009 through 2018 that’s responsible for the lion’s share of exoplanet detections—it’s claimed that four exoplanets have been misclassified.

The authors estimate Kepler-854b, Kepler-840b and Kepler-699b to be between two and four times the size of Jupiter. They used new data on the measurements of planets from the new Gaia mission, which has been precisely measuring and mapping the properties and movements of stars in the Milky Way.

In short, they’re stars, not planets.

Could there be more rogue stars masquerading as planets in NASA’s Exoplanet Archive? probably not. “This is a tiny correction [that] comes from the better understanding of stars, which is only improving all the time,” said Shporer. “These misclassifications are not going to happen many times more.”

Four Of Our Planets Are Missing. NASA Announces 5,000th New Alien World But Some Are Imposters Say Scientists

Are there rogue stars masquerading as planets in NASA’s Exoplanet Archive?

www.forbes.com

View: https://youtu.be/2qDg5uHk-4c

 

[Archibald]

5000 exoplanets. Wow. I still remember October 1995, when the first was discovered. By 1998 there were perhaps half a dozen.

 

[Flyaway]

5000 exoplanets. Wow. I still remember October 1995, when the first was discovered. By 1998 there were perhaps half a dozen.

The first exoplanet is still an odd one being as it was discovered orbiting a white dwarf if memory serves me right.

 

[Archibald]

Some were found as early as 1992 but orbiting a pulsar (!)

 

[Flyaway]

Some were found as early as 1992 but orbiting a pulsar (!)

Thanks for the correction.

 

[publiusr]

47 Ursae Majoris stands out for me…that and the TRAPPIST system.

Everything else is hot Jupiters and water world Neptune’s or something…. :O

 

[Rhinocrates]

The World’s Most Capable Space Telescope Readies To Observe. What Will Exoplanet Scientists Be Looking For?

The decades-long process of developing, refining, testing, launching, unfurling and now aligning and calibrating the most capable space telescope in history is nearing fruition. While NASA has alr…

manyworlds.space

My feelings on this...

View: https://www.youtube.com/watch?v=8iwBM_YB1sE&ab_channel=PointerSistersVEVO

 

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LADUMA: Discovery of a luminous OH megamaser at z>0.5

In the local Universe, OH megamasers (OHMs) are detected almost exclusively in infrared-luminous galaxies, with a prevalence that increases with IR luminosity, suggesting that they trace gas-rich galaxy mergers. Given the proximity of the rest frequencies of OH and the hyperfine transition of neutral atomic hydrogen (HI), radio surveys to probe the cosmic evolution of HI in galaxies also offer exciting prospects for exploiting OHMs to probe the cosmic history of gas-rich mergers. Using observations for the Looking At the Distant Universe with the MeerKAT Array (LADUMA) deep HI survey, we report the first untargeted detection of an OHM at z>0.5, LADUMA J033046.20−275518.1 (nicknamed "Nkalakatha"). The host system, WISEA J033046.26−275518.3, is an infrared-luminous radio galaxy whose optical redshift z≈0.52 confirms the MeerKAT emission line detection as OH at a redshift zOH=0.5225±0.0001 rather than HI at lower redshift. The detected spectral line has 18.4σ peak significance, a width of 459±59kms−1, and an integrated luminosity of (6.31±0.18[statistical]±0.31[systematic])×103L⊙, placing it among the most luminous OHMs known. The galaxy's far-infrared luminosity LFIR=(1.576±0.013)×1012L⊙ marks it as an ultra-luminous infrared galaxy; its ratio of OH and infrared luminosities is similar to those for lower-redshift OHMs. A comparison between optical and OH redshifts offers a slight indication of an OH outflow. This detection represents the first step towards a systematic exploitation of OHMs as a tracer of galaxy growth at high redshifts.

[2204.02523] LADUMA: Discovery of a luminous OH megamaser at $z > 0.5$

arxiv.org

Using the MeerKAT radio telescope, a team of researchers from the University of the Western Cape, the University of Cape Town, Rhodes University, the South African Radio Astronomy Observatory and the South African Astronomical Observatory together with colleagues from twelve other countries have discovered a powerful megamaser – a radio-wavelength laser indicative of colliding galaxies. This is the most distant such megamaser found so far.

Megamaser “Nkalakatha” discovered by astronomers using MeerKAT

Using the MeerKAT radio telescope, a team of researchers from the University of the Western Cape, the University of Cape Town, Rhodes University, the South African Radio Astronomy Observatory and t…

astro.uwc.ac.za

 

[Flyaway]

Space Force is Releasing Decades of Tracking Data on a Thousand Bright Meteor Fireballs

Space Force is Releasing Decades of Tracking Data on a Thousand Bright Meteor Fireballs

When a meteoroid enters the Earth’s atmosphere at a very high speed it heats up. This heating up produces a streak of light and is termed a meteor. When a meteor is bright enough, about the brightness of Venus or brighter, it becomes a fireball. Sometimes these fireballs explode in the...

www.universetoday.com

 

[publiusr]

Good. Shutting down DSP data sharing was a mistake.

 

[Flyaway]

U.S. Space Force Releases Decades of Bolide Data to NASA for Planetary Defense Studies

An agreement between NASA and the U.S. Space Force recently authorized the public release of decades of data collected by U.S. government sensors on fireball events (large bright meteors also known as bolides) for the benefit of the scientific and planetary defense communities. This action results from collaboration between NASA’s Planetary Defense Coordination Office (PDCO) and the U.S. Space Force to continue furthering our nation’s efforts in planetary defense, which include finding, tracking, characterizing, and cataloguing near-Earth objects (NEOs). The newly released data is comprised of information on the changing brightness of bolides as they pass through Earth’s atmosphere, called light curves, that could enhance the planetary defense community’s current ability to model the effects of impacts by larger asteroids that could one day pose a threat to Earth.

Bolides, very bright meteors that can even be seen in daylight, are a regular occurrence – on the order of several dozen times per year – that result when our planet is impacted by asteroids too small to reach the ground but large enough to explode upon impact with Earth’s atmosphere. U.S. government sensors detect these atmospheric impact events, and the bolide data is reported to the NASA Jet Propulsion Laboratory’s Center for Near Earth Object Studies (CNEOS) fireballs database, which contains data going back to 1988 for nearly one thousand bolide events. Now, planetary defense experts will have access to even more detailed data – specifically, light curve information that captures the optical intensity variation during the several seconds of an object’s breakup in the atmosphere. The data will be available to scientists as soon as it is properly archived, with the reported events and made easily accessible. This uniquely rich data set has been greatly sought after by the scientific community as an object’s breakup in Earth’s atmosphere provides scientific insight into the object’s strength and composition based on what altitudes at which it breaks up and disintegrates. The approximate total radiated energy and pre-entry velocity vector (i.e., direction) can also be better derived from bolide light curve data.

“The growing archive of bolide reports, as posted on the NASA CNEOS Fireballs website, has significantly increased scientific knowledge and contributes to the White House approved National Near-Earth Object Preparedness Strategy and Action Plan” said Lindley Johnson, planetary defense officer at NASA Headquarters. “The release of these new bolide data demonstrates another key area of collaboration between NASA and the U.S. Space Force and helps further the pursuit of improved capabilities for understanding these objects and our preparedness to respond to the impact hazard NEOs pose to Earth.”

Recently a small asteroid approximately 2 meters in size, so small it posed no hazard to Earth, was detected in space as it approached Earth and impacted the atmosphere southwest of Jan Mayen, a Norwegian island nearly 300 miles (470 kilometers) off the east coast of Greenland and northeast of Iceland. While this asteroid, designated 2022 EB5, was much smaller than objects NASA is tasked to detect and warn about, CNEOS continued to update NASA’s PDCO with impact location predictions as observations were collected leading up to 2022 EB5’s impact, offering the planetary defense community a real-word scenario to test NEO tracking capabilities and give confidence that the impact prediction process and models are adequate for timely and accurate notification of the potential impact of a larger object, should one be discovered on a trajectory toward Earth. Like other bolide events, 2022 EB5’s impact was detected by U.S. Government sensors and reported by the U.S. Space Force units, confirming the time and location predicted by CNEOS, and added to NASA's archive of these events at JPL CNEOS.

Another notable bolide event in this released data set is of a meteor that was detected on Jan 8, 2014. This object gained the interest of the scientific community as it has been posited it could have interstellar origin due to the detected event’s high velocity within the atmosphere. Further analysis carried out under U.S. Space Command’s purview confirmed the object’s high velocity impact, but the short duration of collected data, less than five seconds, makes it difficult to definitively determine if the object’s origin was indeed interstellar.

NASA established the PDCO in 2016 to manage the agency’s ongoing efforts in planetary defense. NASA has been directed to discover 90% of NEOs larger than 140 meters (459 feet) in size. The agency is diligently working to achieve this directive and has currently found approximately 40% of near-Earth asteroids larger than that size.

For more information about PDCO, visit:

Planetary Defense at NASA - NASA Science

www.nasa.gov

Follow NASA Asteroid Watch on Twitter at @AsteroidWatch.

Josh Handal / Karen Fox
Headquarters, Washington
202-358-1600 / 301-286-6284
joshua.a.handal@nasa.gov / karen.c.fox@nasa.gov

U.S. Space Force Releases Decades of Bolide Data to NASA for Planetary Defense Studies - NASA

An agreement between NASA and the U.S. Space Force recently authorized the public release of decades of data collected by U.S. government sensors on fireball

www.nasa.gov

 

[Flyaway]

What’s Happening To Neptune? Massive Telescopes See Something Weird Going On With The Eighth Planet

Something unexpected is happening on Neptune and astronomers aren’t sure why.

Using a fleet of ground-based telescopes—including the massive Very Large Telescope in Chile—an international team of astronomers have seem some dramatic temperature changes on the eight planet from the Sun.

It’s now become clear that over the last 17 years there’s been a surprising drop in Neptune’s global temperatures followed by a dramatic warming at its south pole. The findings are published today in The Planetary Science Journal.

“This change was unexpected,” said Michael Roman, a postdoctoral research associate at the University of Leicester in the U.K and lead author of the study. “Since we have been observing Neptune during its early southern summer, we expected temperatures to be slowly growing warmer, not colder.”

Seasons are long on Neptune. The “ice giant” orbits the Sun once every 165 -Earth years, so variations on long timescales are expected roughly every 40 years.

What’s Happening To Neptune? Massive Telescopes See Something Weird Going On With The Eighth Planet

Surprised astronomers have watched a drop in Neptune’s global temperatures followed by a dramatic warming at its south pole. What's happening on the "ice giant" and should NASA send a spacecraft to investigate?

www.forbes.com

Evolution of thermal images from Neptune:

View: https://youtu.be/gMzz1Fs83EU

 

[Rhinocrates]

The NAA Decadal Survey is out. The most exciting element is that a Uranus orbiter with atmospheric probe is a top priority, as is a return to Enceladus. Uranus was chosen over Neptune & Triton because of the time needed to reach it (13 years). Europa lander has slipped.

Planetary Science Decadal Survey: After the Red Planet, an Ice Giant

After completing Mars Sample Return, Uranus should be the target of NASA's next major planetary mission, according to a major new report by the National…

www.planetary.org

Science | AAAS

www.science.org

Origins, Worlds, and Life: A Decadal Strategy for Planetary Science and Astrobiology 2023-2032 | The National Academies Press

Read online, download a free PDF, or order a copy in print or as an eBook.

nap.nationalacademies.org

 

[Flyaway]

Micronovae - a New Kind of Stellar Explosion (ESOcast 254 Light)

View: https://youtu.be/XouB5QYnAVM

 

[Rhinocrates]

Interstellar Probe. This is a proposal for a probe into the interstellar medium, not to another star. A point worth making is that this is the environment where real starships are going to spend almost all their time, measured in several decades at the very least and perhaps millennia.

NASA Interstellar Probe: Overview and Prospects | Centauri Dreams

https://www.sciencedirect.com/science/article/pii/S0094576522001503

 

[Rhinocrates]

[2204.04866] Resolved imaging of exoplanets with the solar gravitational lens

arxiv.org

We discuss the feasibility of direct multipixel imaging of exoplanets with the solar gravitational lens (SGL) in the context of a realistic deep space mission. For this, we consider an optical telescope, placed in the image plane that forms in the strong interference region of the SGL. We consider an Earth-like exoplanet located in our immediate stellar neighborhood and model its characteristics using our own Earth. We estimate photon fluxes from such a compact, extended, resolved exoplanet. This light appears in the form of an Einstein ring around the Sun, seen through the solar corona. The solar corona background contributes a significant amount of stochastic noise and represents the main noise source for observations utilizing the SGL. We estimate the magnitude of this noise. We compute the resulting signal-no-noise ratios and related integration times that are needed to perform imaging measurements under realistic conditions. We conclude that an imaging mission is challenging but feasible, using technologies that are either already available or in active development. Under realistic conditions, megapixel imaging of Earth-like exoplanets in our galactic neighborhood requires only weeks or months of integration time, not years as previously thought.

 

[Flyaway]

WASHINGTON — A handful of ancient zircon crystals found in South Africa hold the oldest evidence of subduction, a key element of plate tectonics, according to a new study published today in AGU Advances, AGU’s journal for high-impact, open-access research and commentary across the Earth and space sciences.

These rare time capsules from Earth’s youth point to a transition around 3.8 billion years ago from a long-lived, stable rock surface to the active processes that shape our planet today, providing a new clue in a hot debate about when plate tectonics was set in motion.

Earliest geochemical evidence of plate tectonics found in 3.8-billion-year-old crystal

Tiny zircons found in South Africa point to an early start for the active global process that shapes Earth’s surface and climate.

news.agu.org

 

[Flyaway]

Scientists recently observed two black holes that united into one, and in the process got a “kick” that flung the newly formed black hole away at high speed. That black hole zoomed off at about 5 million kilometers per hour, give or take a few million, researchers report in a paper in press in Physical Review Letters. That’s blazingly quick: The speed of light is just 200 times as fast.

Gravitational waves gave a new black hole a high-speed 'kick'

Ripples in spacetime revealed that two black holes united into one, which then sped off at around 5 million kilometers per hour.

www.sciencenews.org

 

[Flyaway]

Double ridge formation over shallow water sills on Jupiter’s moon Europa

Abstract
Jupiter’s moon Europa is a prime candidate for extraterrestrial habitability in our solar system. The surface landforms of its ice shell express the subsurface structure, dynamics, and exchange governing this potential. Double ridges are the most common surface feature on Europa and occur across every sector of the moon, but their formation is poorly understood, with current hypotheses providing competing and incomplete mechanisms for the development of their distinct morphology. Here we present the discovery and analysis of a double ridge in Northwest Greenland with the same gravity-scaled geometry as those found on Europa. Using surface elevation and radar sounding data, we show that this double ridge was formed by successive refreezing, pressurization, and fracture of a shallow water sill within the ice sheet. If the same process is responsible for Europa’s double ridges, our results suggest that shallow liquid water is spatially and temporally ubiquitous across Europa’s ice shell.

Double ridge formation over shallow water sills on Jupiter’s moon Europa - Nature Communications

The formation of double ridges on Europa is poorly understood. Here the authors analyze airborne radar observations of an analog feature on the Greenland Ice Sheet to show that the refreezing of shallow water sills may produce such ridges.

www.nature.com

 

[Flyaway]

I am guessing this will be an image of Sagittarius A*.

Media Advisory 22-001
Event Horizon Telescope Collaboration to announce groundbreaking results about the center of our galaxy

April 28, 2022

The U.S. National Science Foundation with the Event Horizon Telescope Collaboration will hold a press conference to announce a groundbreaking discovery in the Milky Way.

LOCATION – The National Press Club, 529 14th St N.W., Washington, D.C., 20045. The event will also be streamed live online.

Who: NSF's Chief Operating Officer Karen Marrongelle will deliver opening remarks. A panel of Event Horizon Telescope, or EHT, researchers will present their findings and answer questions from the media:

Katherine (Katie) L. Bouman, Assistant Professor of Computing and Mathematical Sciences, Electrical Engineering and Astronomy at Caltech
Vincent Fish, Research Scientist at MIT Haystack Observatory
Feryal Özel, Professor, Departments of Astronomy and Physics at University of Arizona
Michael Johnson, Astrophysicist at Center for Astrophysics | Harvard & Smithsonian
What: Press conference on groundbreaking result from the Event Horizon Telescope.

When: Thursday, May 12, 2022, 9 a.m. EDT.

Where: The National Press Club, 529 14th St N.W., Washington, D.C., 20045. The event will also be streamed live online at https://nsf.gov/blackholes and on NSF's Facebook page at https://www.facebook.com/US.NSF.

RSVP: Credentialed press can register to attend the event in person by contacting eht@nsf.gov. Please provide name of individual asking to attend, their title and the name of the outlet being represented. You will receive a confirmation email if your registration is accepted. The deadline to register is 6:00 p.m. EDT on Monday, May 9. Details about submitting questions or scheduling interviews will be sent to journalists with the registration confirmation NLT May 11.

Immediately following the press conference, panelists and other experts from the EHT collaboration will be available for interviews.

NSF will issue a press release the morning of the press conference along with supporting material. Supporting material will also be available at https://nsf.gov/blackholes.

In addition to the press briefing in the U.S., press conferences will be held simultaneously in Garching bei München (near Munich), Mexico City, Santiago de Chile, Shanghai, Tokyo, and Taipei. If you wish to embed the press conference in your online feed, you may do so from the NSF direct livestream link. The NSF Black Holes page includes additional information about exploring and studying black holes.

A separate panel of EHT researchers will participate in a public Q&A panel at 10:30 a.m. EDT. The public Q&A panel will also be available to view on the NSF Black Holes Website and NSF's Facebook page. Participants include:

Kazu Akiyama, Research Scientist, MIT Haystack Observatory
Richard Anantua, Assistant Professor of Physics & Astronomy at the University of Texas at San Antonio and Associate at the Harvard College Observatory
Daryl Haggard, Associate Professor of Physics at McGill University and the McGill Space Institute
Lia Medeiros, NSF Postdoctoral Fellow at the Institute for Advanced Study
Dom Pesce, Astrophysicist, Center for Astrophysics | Harvard & Smithsonian and Black Hole Initiative at Harvard University
For further information about EHT, please visit the Event Horizon Telescope webpage.

The information in this press advisory is strictly for media planning purposes and is embargoed until May 12, 2022.

-NSF-

 

[Flyaway]

Speculation regarding the above:

Astronomers Tease 'Groundbreaking Result' of Milky Way's Black Hole

We could soon see the Milky Way's supermassive black hole for the first time.

www.cnet.com

 

[Flyaway]

NASA’s Black Hole Orrery:

View: https://youtu.be/NqOhCBRnrnA

 

[Flyaway]

A 62-minute orbital period black widow binary in a wide hierarchical triple

Abstract
Over a dozen millisecond pulsars are ablating low-mass companions in close binary systems. In the original ‘black widow’, the eight-hour orbital period eclipsing pulsar PSR J1959+2048 (PSR B1957+20)1, high-energy emission originating from the pulsar2 is irradiating and may eventually destroy3 a low-mass companion. These systems are not only physical laboratories that reveal the interesting results of exposing a close companion star to the relativistic energy output of a pulsar, but are also believed to harbour some of the most massive neutron stars4, allowing for robust tests of the neutron star equation of state. Here we report observations of ZTF J1406+1222, a wide hierarchical triple hosting a 62-minute orbital period black widow candidate, the optical flux of which varies by a factor of more than ten. ZTF J1406+1222 pushes the boundaries of evolutionary models5, falling below the 80-minute minimum orbital period of hydrogen-rich systems. The wide tertiary companion is a rare low-metallicity cool subdwarf star, and the system has a Galactic halo orbit consistent with passing near the Galactic Centre, making it a probe of formation channels, neutron star kick physics6 and binary evolution.

A 62-minute orbital period black widow binary in a wide hierarchical triple - Nature

ZTF J1406+1222 is a wide hierarchical triple system that hosts a low-metallicity subdwarf star and a ‘black widow’ millisecond pulsar that has a highly varying optical flux and a 62-minute period.

www.nature.com

“Black widow” neutron star takes an hour to orbit the star it’s roasting

Once an hour, the side of a star bombarded by radiation comes into view.

arstechnica.com

 

[Flyaway]

SGR-A*

View: https://youtu.be/3xgc1651Als

 

[Flyaway]

eso2208-eht-mw — Science Release
Astronomers reveal first image of the black hole at the heart of our galaxy

Today, at simultaneous press conferences around the world, including at the European Southern Observatory (ESO) headquarters in Germany, astronomers have unveiled the first image of the supermassive black hole at the centre of our own Milky Way galaxy. This result provides overwhelming evidence that the object is indeed a black hole and yields valuable clues about the workings of such giants, which are thought to reside at the centre of most galaxies. The image was produced by a global research team called the Event Horizon Telescope (EHT) Collaboration, using observations from a worldwide network of radio telescopes.

The image is a long-anticipated look at the massive object that sits at the very centre of our galaxy. Scientists had previously seen stars orbiting around something invisible, compact, and very massive at the centre of the Milky Way. This strongly suggested that this object — known as Sagittarius A* (Sgr A*, pronounced "sadge-ay-star") — is a black hole, and today’s image provides the first direct visual evidence of it.

Although we cannot see the black hole itself, because it is completely dark, glowing gas around it reveals a telltale signature: a dark central region (called a shadow) surrounded by a bright ring-like structure. The new view captures light bent by the powerful gravity of the black hole, which is four million times more massive than our Sun.

“We were stunned by how well the size of the ring agreed with predictions from Einstein’s Theory of General Relativity," said EHT Project Scientist Geoffrey Bower from the Institute of Astronomy and Astrophysics, Academia Sinica, Taipei. "These unprecedented observations have greatly improved our understanding of what happens at the very centre of our galaxy, and offer new insights on how these giant black holes interact with their surroundings." The EHT team's results are being published today in a special issue of The Astrophysical Journal Letters.

Because the black hole is about 27 000 light-years away from Earth, it appears to us to have about the same size in the sky as a doughnut on the Moon. To image it, the team created the powerful EHT, which linked together eight existing radio observatories across the planet to form a single “Earth-sized” virtual telescope [1]. The EHT observed Sgr A* on multiple nights in 2017, collecting data for many hours in a row, similar to using a long exposure time on a camera.

In addition to other facilities, the EHT network of radio observatories includes the Atacama Large Millimeter/submillimeter Array (ALMA) and the Atacama Pathfinder EXperiment (APEX) in the Atacama Desert in Chile, co-owned and co-operated by ESO on behalf of its member states in Europe. Europe also contributes to the EHT observations with other radio observatories — the IRAM 30-meter telescope in Spain and, since 2018, the NOrthern Extended Millimeter Array (NOEMA) in France — as well as a supercomputer to combine EHT data hosted by the Max Planck Institute for Radio Astronomy in Germany. Moreover, Europe contributed with funding to the EHT consortium project through grants by the European Research Council and by the Max Planck Society in Germany.

“It is very exciting for ESO to have been playing such an important role in unravelling the mysteries of black holes, and of Sgr A* in particular, over so many years,” commented ESO Director General Xavier Barcons. “ESO not only contributed to the EHT observations through the ALMA and APEX facilities but also enabled, with its other observatories in Chile, some of the previous breakthrough observations of the Galactic centre.” [2]

The EHT achievement follows the collaboration’s 2019 release of the first image of a black hole, called M87*, at the centre of the more distant Messier 87 galaxy.

The two black holes look remarkably similar, even though our galaxy’s black hole is more than a thousand times smaller and less massive than M87* [3]. "We have two completely different types of galaxies and two very different black hole masses, but close to the edge of these black holes they look amazingly similar,” says Sera Markoff, Co-Chair of the EHT Science Council and a professor of theoretical astrophysics at the University of Amsterdam, the Netherlands. "This tells us that General Relativity governs these objects up close, and any differences we see further away must be due to differences in the material that surrounds the black holes.”

This achievement was considerably more difficult than for M87*, even though Sgr A* is much closer to us. EHT scientist Chi-kwan (‘CK’) Chan, from Steward Observatory and Department of Astronomy and the Data Science Institute of the University of Arizona, USA, explains: “The gas in the vicinity of the black holes moves at the same speed — nearly as fast as light — around both Sgr A* and M87*. But where gas takes days to weeks to orbit the larger M87*, in the much smaller Sgr A* it completes an orbit in mere minutes. This means the brightness and pattern of the gas around Sgr A* were changing rapidly as the EHT Collaboration was observing it — a bit like trying to take a clear picture of a puppy quickly chasing its tail.”

The researchers had to develop sophisticated new tools that accounted for the gas movement around Sgr A*. While M87* was an easier, steadier target, with nearly all images looking the same, that was not the case for Sgr A*. The image of the Sgr A* black hole is an average of the different images the team extracted, finally revealing the giant lurking at the centre of our galaxy for the first time.

The effort was made possible through the ingenuity of more than 300 researchers from 80 institutes around the world that together make up the EHT Collaboration. In addition to developing complex tools to overcome the challenges of imaging Sgr A*, the team worked rigorously for five years, using supercomputers to combine and analyse their data, all while compiling an unprecedented library of simulated black holes to compare with the observations.

Scientists are particularly excited to finally have images of two black holes of very different sizes, which offers the opportunity to understand how they compare and contrast. They have also begun to use the new data to test theories and models of how gas behaves around supermassive black holes. This process is not yet fully understood but is thought to play a key role in shaping the formation and evolution of galaxies.

“Now we can study the differences between these two supermassive black holes to gain valuable new clues about how this important process works,” said EHT scientist Keiichi Asada from the Institute of Astronomy and Astrophysics, Academia Sinica, Taipei. “We have images for two black holes — one at the large end and one at the small end of supermassive black holes in the Universe — so we can go a lot further in testing how gravity behaves in these extreme environments than ever before.”

Progress on the EHT continues: a major observation campaign in March 2022 included more telescopes than ever before. The ongoing expansion of the EHT network and significant technological upgrades will allow scientists to share even more impressive images as well as movies of black holes in the near future.

Notes
[1] The individual telescopes involved in the EHT in April 2017, when the observations were conducted, were: the Atacama Large Millimeter/submillimeter Array (ALMA), the Atacama Pathfinder EXperiment (APEX), the IRAM 30-meter Telescope, the James Clerk Maxwell Telescope (JCMT), the Large Millimeter Telescope Alfonso Serrano (LMT), the Submillimeter Array (SMA), the UArizona Submillimeter Telescope (SMT), the South Pole Telescope (SPT). Since then, the EHT has added the Greenland Telescope (GLT), the NOrthern Extended Millimeter Array (NOEMA) and the UArizona 12-meter Telescope on Kitt Peak to its network.

ALMA is a partnership of the European Southern Observatory (ESO; Europe, representing its member states), the U.S. National Science Foundation (NSF), and the National Institutes of Natural Sciences (NINS) of Japan, together with the National Research Council (Canada), the Ministry of Science and Technology (MOST; Taiwan), Academia Sinica Institute of Astronomy and Astrophysics (ASIAA; Taiwan), and Korea Astronomy and Space Science Institute (KASI; Republic of Korea), in cooperation with the Republic of Chile. The Joint ALMA Observatory is operated by ESO, the Associated Universities, Inc./National Radio Astronomy Observatory (AUI/NRAO) and the National Astronomical Observatory of Japan (NAOJ). APEX, a collaboration between the Max Planck Institute for Radio Astronomy (Germany), the Onsala Space Observatory (Sweden) and ESO, is operated by ESO. The 30-meter Telescope is operated by IRAM (the IRAM Partner Organizations are MPG [Germany], CNRS [France] and IGN [Spain]). The JCMT is operated by the East Asian Observatory on behalf of The National Astronomical Observatory of Japan; ASIAA; KASI; the National Astronomical Research Institute of Thailand; the Center for Astronomical Mega-Science and organisations in the United Kingdom and Canada. The LMT is operated by INAOE and UMass, the SMA is operated by Center for Astrophysics | Harvard & Smithsonian and ASIAA and the UArizona SMT is operated by the University of Arizona. The SPT is operated by the University of Chicago with specialised EHT instrumentation provided by the University of Arizona.

The Greenland Telescope (GLT) is operated by ASIAA and the Smithsonian Astrophysical Observatory (SAO). The GLT is part of the ALMA-Taiwan project, and is supported in part by the Academia Sinica (AS) and MOST. NOEMA is operated by IRAM and the UArizona 12-meter telescope at Kitt Peak is operated by the University of Arizona.

[2] A strong basis for the interpretation of this new image was provided by previous research carried out on Sgr A*. Astronomers have known the bright, dense radio source at the centre of the Milky Way in the direction of the constellation Sagittarius since the 1970s. By measuring the orbits of several stars very close to our galactic centre over a period of 30 years, teams led by Reinhard Genzel (Director at the Max –Planck Institute for Extraterrestrial Physics in Garching near Munich, Germany) and Andrea M. Ghez (Professor in the Department of Physics and Astronomy at the University of California, Los Angeles, USA) were able to conclude that the most likely explanation for an object of this mass and density is a supermassive black hole. ESO's facilities (including the Very Large Telescope and the Very Large Telescope Interferometer) and the Keck Observatory were used to carry out this research, which shared the 2020 Nobel Prize in Physics.

[3] Black holes are the only objects we know of where mass scales with size. A black hole a thousand times smaller than another is also a thousand times less massive.

More information
This research was presented in six papers published today in The Astrophysical Journal Letters.

The EHT collaboration involves more than 300 researchers from Africa, Asia, Europe, North and South America. The international collaboration aims to capture the most detailed black hole images ever obtained by creating a virtual Earth-sized telescope. Supported by considerable international efforts, the EHT links existing telescopes using novel techniques — creating a fundamentally new instrument with the highest angular resolving power that has yet been achieved.

The EHT consortium consists of 13 stakeholder institutes; the Academia Sinica Institute of Astronomy and Astrophysics, the University of Arizona, the Center for Astrophysics | Harvard & Smithsonian, the University of Chicago, the East Asian Observatory, Goethe-Universitaet Frankfurt, Institut de Radioastronomie Millimétrique, Large Millimeter Telescope, Max Planck Institute for Radio Astronomy, MIT Haystack Observatory, National Astronomical Observatory of Japan, Perimeter Institute for Theoretical Physics, and Radboud University.

The Atacama Large Millimeter/submillimeter Array (ALMA), an international astronomy facility, is a partnership of ESO, the U.S. National Science Foundation (NSF) and the National Institutes of Natural Sciences (NINS) of Japan in cooperation with the Republic of Chile. ALMA is funded by ESO on behalf of its Member States, by NSF in cooperation with the National Research Council of Canada (NRC) and the Ministry of Science and Technology (MOST) and by NINS in cooperation with the Academia Sinica (AS) in Taiwan and the Korea Astronomy and Space Science Institute (KASI). ALMA construction and operations are led by ESO on behalf of its Member States; by the National Radio Astronomy Observatory (NRAO), managed by Associated Universities, Inc. (AUI), on behalf of North America; and by the National Astronomical Observatory of Japan (NAOJ) on behalf of East Asia. The Joint ALMA Observatory (JAO) provides the unified leadership and management of the construction, commissioning and operation of ALMA.

APEX, Atacama Pathfinder EXperiment, is a 12-metre diameter telescope, operating at millimetre and submillimetre wavelengths — between infrared light and radio waves. ESO operates APEX at one of the highest observatory sites on Earth, at an elevation of 5100 metres, high on the Chajnantor plateau in Chile’s Atacama region. The telescope is a collaboration between the Max Planck Institute for Radio Astronomy (MPIfR), the Onsala Space Observatory (OSO), and ESO.

The European Southern Observatory (ESO) enables scientists worldwide to discover the secrets of the Universe for the benefit of all. We design, build and operate world-class observatories on the ground — which astronomers use to tackle exciting questions and spread the fascination of astronomy — and promote international collaboration in astronomy. Established as an intergovernmental organisation in 1962, today ESO is supported by 16 Member States (Austria, Belgium, the Czech Republic, Denmark, France, Finland, Germany, Ireland, Italy, the Netherlands, Poland, Portugal, Spain, Sweden, Switzerland and the United Kingdom), along with the host state of Chile and with Australia as a Strategic Partner. ESO’s headquarters and its visitor centre and planetarium, the ESO Supernova, are located close to Munich in Germany, while the Chilean Atacama Desert, a marvellous place with unique conditions to observe the sky, hosts our telescopes. ESO operates three observing sites: La Silla, Paranal and Chajnantor. At Paranal, ESO operates the Very Large Telescope and its Very Large Telescope Interferometer, as well as two survey telescopes, VISTA working in the infrared and the visible-light VLT Survey Telescope. Also at Paranal ESO will host and operate the Cherenkov Telescope Array South, the world’s largest and most sensitive gamma-ray observatory. Together with international partners, ESO operates APEX and ALMA on Chajnantor, two facilities that observe the skies in the millimetre and submillimetre range. At Cerro Armazones, near Paranal, we are building “the world’s biggest eye on the sky” — ESO’s Extremely Large Telescope. From our offices in Santiago, Chile we support our operations in the country and engage with Chilean partners and society.

Links
Main papers:
Paper I: The Shadow of the Supermassive Black Hole in the Center of the Milky Way
Paper II: EHT and Multi-wavelength Observations, Data Processing, and Calibration
Paper III: Imaging of the Galactic Center Supermassive Black Hole
Paper IV: Variability, Morphology, and Black Hole Mass
Paper V: Testing Astrophysical Models of the Galactic Center Black Hole
Paper VI: Testing the Black Hole Metric
Supplementary papers:
Selective Dynamical Imaging of Interferometric Data
Millimeter Light Curves of Sagittarius A* Observed during the 2017 Event Horizon Telescope Campaign
A Universal Power Law Prescription for Variability from Synthetic Images of Black Hole Accretion Flows
Characterizing and Mitigating Intraday Variability: Reconstructing Source Structure in Accreting Black Holes with mm-VLBI
ESO EHT web page
EHT Website & Press Release
Images of ALMA
Images of APEX
Contacts
Geoffrey Bower
EHT Project Scientist, Institute of Astronomy and Astrophysics, Academic Sinica, Taipei and University of Hawaiʻi at Mānoa, US
Tel: +1-808-961-2945
Email: gbower@asiaa.sinica.edu.tw

Huib Jan van Langevelde
EHT Project Director, JIVE and University of Leiden
Leiden, The Netherlands
Tel: +31-521-596515
Email: huib.van.langevelde@me.com

Bárbara Ferreira
ESO Media Manager
Garching bei München, Germany
Tel: +49 89 3200 6670
Cell: +49 151 241 664 00
Email: press@eso.org

Connect with ESO on social media

Astronomers reveal first image of the black hole at the heart of our galaxy

Today, at simultaneous press conferences around the world, including at the European Southern Observatory (ESO) headquarters in Germany, astronomers have unveiled the first image of the supermassive black hole at the centre of our own Milky Way galaxy. This result provides overwhelming evidence...

www.eso.org

 

[Flyaway]

The latest observations are already giving intriguing hints about the nature of our own black hole. Simulations based on the data hint that our black hole’s angle of rotation is not neatly aligned with the galactic plain, but is off-kilter by about 30 degrees. The observations also suggest that SgrA* is in a dormant state, in contrast with some black holes, including M87, which feature vast, powerful jets that blast light and matter from the black hole’s poles into intergalactic space. “If a big star fell in, which would happen every 10,000 years, that would wake it up for a short amount of time and we’d see things brighten up,” said Markoff.

Supermassive black hole at centre of Milky Way seen for first time | Space | The Guardian

Event Horizon telescope captures image giving a glimpse of the turbulent heart of our galaxy

amp.theguardian.com

 

[FighterJock]

The latest observations are already giving intriguing hints about the nature of our own black hole. Simulations based on the data hint that our black hole’s angle of rotation is not neatly aligned with the galactic plain, but is off-kilter by about 30 degrees. The observations also suggest that SgrA* is in a dormant state, in contrast with some black holes, including M87, which feature vast, powerful jets that blast light and matter from the black hole’s poles into intergalactic space. “If a big star fell in, which would happen every 10,000 years, that would wake it up for a short amount of time and we’d see things brighten up,” said Markoff.

Supermassive black hole at centre of Milky Way seen for first time | Space | The Guardian

Event Horizon telescope captures image giving a glimpse of the turbulent heart of our galaxy

amp.theguardian.com

Interesting news Flyaway, so the latest research suggests that SgrA* is in a dormant state, it would be interesting to see what happens when the Andromeda Galaxy (M-31) hits us in about a billion or so years time.

 

[Flyaway]

The latest observations are already giving intriguing hints about the nature of our own black hole. Simulations based on the data hint that our black hole’s angle of rotation is not neatly aligned with the galactic plain, but is off-kilter by about 30 degrees. The observations also suggest that SgrA* is in a dormant state, in contrast with some black holes, including M87, which feature vast, powerful jets that blast light and matter from the black hole’s poles into intergalactic space. “If a big star fell in, which would happen every 10,000 years, that would wake it up for a short amount of time and we’d see things brighten up,” said Markoff.

Supermassive black hole at centre of Milky Way seen for first time | Space | The Guardian

Event Horizon telescope captures image giving a glimpse of the turbulent heart of our galaxy

amp.theguardian.com

Interesting news Flyaway, so the latest research suggests that SgrA* is in a dormant state, it would be interesting to see what happens when the Andromeda Galaxy (M-31) hits us in about a billion or so years time.

Apparently its material intake is equivalent to a human eating one grain of rice every million years. There is evidence of jets of gas in the past so it has not always been so dormant. The other surprising thing is the fact it is tipped up so it’s face onto us to some degree.

 

[Flyaway]

What it Takes to Image a Black Hole:

View: https://youtu.be/D3m-GtAt5hY

Size comparison of the two EHT black holes:

View: https://youtu.be/UOESt-G34vE

Clustering and averaging the images of Sagittarius A* and M87*:

View: https://youtu.be/dXRACQC9kU0

Meet Sgr A*: Zooming into the black hole at the centre of our galaxy:

View: https://youtu.be/Zml0dZCjaFw

 

[Orionblamblam]

View: https://www.youtube.com/watch?v=ZQDikuozNbg

 

[Flyaway]

Bilayer Graphene Inspires Two-Universe Cosmological Model

In a new paper in Physical Review Research(link is external), JQI Fellow Victor Galitski and JQI graduate student Alireza Parhizkar have explored the imaginative possibility that our reality is only one half of a pair of interacting worlds. Their mathematical model may provide a new perspective for looking at fundamental features of reality—including why our universe expands the way it does and how that relates to the most miniscule lengths allowed in quantum mechanics. These topics are crucial to understanding our universe and are part of one of the great mysteries of modern physics.

The pair of scientists stumbled upon this new perspective when they were looking into research on sheets of graphene—single atomic layers of carbon in a repeating hexagonal pattern. They realized that experiments on the electrical properties of stacked sheets of graphene produced results that looked like little universes and that the underlying phenomenon might generalize to other areas of physics. In stacks of graphene, new electrical behaviors arise from interactions between the individual sheets, so maybe unique physics could similarly emerge from interacting layers elsewhere—perhaps in cosmological theories about the entire universe.

The new model produced additional results the researchers find intriguing. As they put together the math, they found that part of the model looked like important fields that are part of reality. The more detailed model still suggests that two worlds could explain a small cosmological constant and provides details about how such a bi-world might imprint a distinct signature on the cosmic background radiation—the light that lingers from the earliest times in the universe.

This signature could possibly be seen—or definitively not be seen—in real world measurements. So future experiments could determine if this unique perspective inspired by graphene deserves more attention or is merely an interesting novelty in the physicists’ toy bin.

“We haven't explored all the effects—that's a hard thing to do, but the theory is falsifiable experimentally, which is a good thing,” Parhizkar says. “If it's not falsified, then it's very interesting because it solves the cosmological constant problem while describing many other important parts of physics. I personally don't have my hopes up for that— I think it is actually too big to be true.”

Bilayer Graphene Inspires Two-Universe Cosmological Model

Physicists sometimes come up with crazy stories that sound like science fiction. Some turn out to be true, like how the curvature of space and time described by Einstein was eventually borne out by astronomical measurements. Others linger on as mere possibilities or mathematical curiosities.In a...

jqi.umd.edu

Related paper:

Moiré Gravity and Cosmology

The vacuum catastrophe is a fundamental puzzle, where the observed scales of the cosmological constant are many orders of magnitude smaller than the natural scales expected in the theory. This work proposes a new "bi-world" construction that may offer an insight into the cosmological constant problem. The model includes a (3+1)-dimensional manifold with two different geometries and matter fields residing on them. The diffeomorphism invariance and causality highly constrain the two metrics to be conformally related, ημν=ϕ2gμν. This reduces the theory to a standard single-world description, but introduces a new inherently geometrical "moiré field," ϕ. Interestingly, the moiré field has the character of both a dilaton and Higgs field familiar in the conventional theory. Integrating out the moiré field naturally gives rise to the Starobinsky action and inflationary dynamics. In the framework of the Friedmann-Lemaitre-Robertson-Walker solution, we reduce an effective action for the moiré field to that of a particle moving in a Mexican hat potential. The equations of motion are then solved numerically and the moiré field is shown to approach a Mexican-hat minimum in an oscillatory fashion, which is accompanied by the decay of the Hubble parameter. Under additional reasonable assumptions, the vacuum energy asymptotically approaches zero in the end of inflationary evolution. The physics presented here shares similarities with the moiré phenomena in condensed matter and elsewhere, where two similar structures superimposed upon give rise to a superstructure with low emergent energy scales compared to the native theories.

[2204.06574] Moiré Gravity and Cosmology

 

[Flyaway]

NuSTAR - Studying the Universe in X-Ray (Live Public Talk) :

View: https://youtu.be/HkfD6mi-ego

 

[Flyaway]

Sonification of NGC 1300:

View: https://youtu.be/zyf1UDm-GyU

 

[Flyaway]

Imaging stars with quantum error correction

The development of high-resolution, large-baseline optical interferometers would revolutionize astro- nomical imaging. However, classical techniques are hindered by physical limitations including loss, noise, and the fact that the received light is generally quantum in nature.

https://arxiv.org/pdf/2204.06044.pdf

 

[Flyaway]

Plato’s cave: vacuum test for exoplanet detection

Plato’s cave: vacuum test for exoplanet detection

www.esa.int

Plato’s cave: vacuum test for exoplanet detection

A test version of the payload module of ESA's exoplanet-detecting Plato spacecraft underwent a prolonged vacuum soak within Europe’s largest thermal vacuum chamber, to evaluate its endurance of space conditions

Testing took place inside ESA’s Large Space Simulator, the largest thermal vacuum chamber in Europe. Standing 15m high by 10m wide the LSS is cavernous enough to encompass an upturned London double decker bus.

The LSS testing began at the end of March and was successfully completed in the third week of May.

 

[Flyaway]

Chandra's High Resolution Camera (HRC) anomaly has been traced to a B-side power supply. Restarting the B-side power supply did not achieve the desired voltages, but the restarted A-side power supply was nominal.

Our investigation continues...

https://twitter.com/x/status/1532783505083486208

View: https://twitter.com/chandraCDO/status/1532783505083486208

 

[Flyaway]

Galaxy cluster collision created 1.6 million mile shockwave:

View: https://youtu.be/lJmFj0upmo0

 

[Flyaway]

The variability behavior of NGC 925 ULX-3

We report the results of a 2019-2021 monitoring campaign with Swift and associated target-of-opportunity observations with XMM-Newton and NuSTAR, examining the spectral and timing behavior of the highly variable ultraluminous X-ray source (ULX) NGC 925 ULX-3. We find that the source exhibits a 127-128 day periodicity, with fluxes typically ranging from 1e-13 to 8e-13 ergs/s/cm2. We do not find strong evidence for a change in period over the time that NGC 925 ULX-3 has been observed, although the source may have been in a much lower flux state when first observed with Chandra in 2005. We do not detect pulsations, and we place an upper limit on the pulsed fraction of ~40% in the XMM-Newton band, consistent with some previous pulsation detections at low energies in other ULXs. The source exhibits a typical ULX spectrum that turns over in the NuSTAR band and can be fitted using two thermal components. These components have a high temperature ratio that may indicate the lack of extreme inner disk truncation by a magnetar-level magnetic field. We examine the implications for a number of different models for superorbital periods in ULXs, finding that a neutron star with a magnetic field of ~10^12 G may be plausible for this source. The future detection of pulsations from this source would allow for the further testing and constraining of such models.

[2206.08397] The variability behavior of NGC 925 ULX-3