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The term quasar comes from quasi-stellar objects, a name that reflected our uncertainty about their nature. The first quasars were discovered solely because of their radio emissions, with no corresponding visual objects. This is surprising since quasars blaze with the light of trillions of stars.

In recent observations, the Hubble examined a historical quasar named 3C 273, the first quasar to be linked with a visual object.

Maarten Schmidt was the California Institute of Technology astronomer who first connected the radio emissions from 3C 273 with a visual object back in 1963. At the time, it looked just like a star through the powerful telescopes available, though its light was red-shifted. Schmidt’s discovery showed us the true nature of these extraordinary objects, and now we know of about one million quasars.

A quasar is an extremely luminous active galactic nucleus (AGN) powered by a supermassive black hole (SMBH) at the center of a galaxy. Accretion disks of gas form around SMBHs, and the swirling gas heats up and releases electromagnetic energy. Only a small percentage of galaxies have quasars and their luminosities can be thousands of times greater than a galaxy like the Milky Way.

3C 273 is about 2.5 billion light-years away and is the most distant object visible in a backyard telescope. Recently, Hubble captured its best view of the quasar, revealing previously unseen details in its vicinity.

The quasar’s blinding light makes its surroundings difficult to discern. However, astronomers figured out a way to use Hubble’s Space Telescope Imaging Spectrograph (STIS) instrument to make coronagraphic observations of the region. The coronograph allowed astronomers to look eight times closer to the black hole than ever before.

The researchers found a new core jet, a core blob, and other smaller blobs. Their results are in a research letter titled “3C 273 Host Galaxy with Hubble Space Telescope Coronagraphy.” It’s published in the journal Astronomy and Astrophysics, and the lead author is Bin Ren, who also happens to be associated with the California Institute of Technology.

Hubble’s STIS coronagraph allowed astronomers to get a clearer look at the region surrounding the quasar 3C 273. Image Credit: NASA, ESA, Bin Ren (Université Côte d’Azur/CNRS)

By blocking out the quasar’s blinding glare, Hubble was able to better examine its surroundings. The astronomers found weird filaments, lobes, and a mysterious L-shaped structure. These are all probably the results of the SMBH devouring small galaxies.

“We have detected a more symmetric core component, CC, for the host galaxy of 3C 273, in addition to confirming the existing large-scale asymmetric components IC and OC that were previously identified in HST/ACS coronagraphy from Martel et al. (2003),” the authors explain in their research letter.

These four images from the research show some of the detail uncovered by the new coronagraphic observations. (a) contains original data. (b) is the isophote model. (c) and (d) are isophote-removed data. (An isophote is a curve on an illuminated surface that connects points of equal brightness.) CC is a newly identified symmetric Core Component, IJ is the Inner Jet, CJ is the newly observed Core Jet, CB is the Core Blob, JC is the Jet Component, and b1, b2 and b3 are newly observed blobs. The filament in panel d is also newly observed. Image Credit: NASA, ESA, Bin Ren (Université Côte d’Azur/CNRS)

“With the STIS coronagraphic observations, we also identify a core blob (CB) component, as well as other point-sourcelike objects, after removing isophotes from the host galaxy,” the authors continue. “The nature of the newly identified components, as well as the point source-like objects, would require observations from other telescopes for further study.”

There are also filamentary structures to the northeast, east, and west of the galactic nucleus. They extend as far as 10 kiloparsecs (32,600 light-years) from the nucleus. The authors explain that they’re similar to structures observed in other galaxies, where they’re thought to be multiphase gas that’s condensing out of the intergalactic medium. This gas could be fuelling AGN feedback. AGN feedback is a self-regulating process that links the energy released by the AGN to the surrounding gaseous medium.

Previous observations of the same quasar 22 years ago allowed the authors to compare images and constrain some properties of the previously observed Inner Jet, which is 300,000 light-years long. “We witness a potential trend that the motion is faster when it is further out,” they write.

This figure from the research shows 200 different randomly sampled components of the jet as grey lines. As the figure shows, the jets move faster the further they are from the source. Image Credit: NASA, ESA, Bin Ren (Université Côte d’Azur/CNRS)

This fascinating object begs for more observations to better understand what’s happening. The authors explain that we need methods and telescopes with better inner working angles (IWA) to do that. Both the Hubble and the JWST can do it. “With smaller IWAs for both telescopes, we can both confirm the existence of closest-in components and constrain their physical properties from multi-band imaging. In high-energy observations, we can better characterize such structures,” the authors explain.

“With the fine spatial structures and jet motion, Hubble bridged a gap between the small-scale radio interferometry and large-scale optical imaging observations, and thus we can take an observational step towards a more complete understanding of quasar host morphology. Our previous view was very limited, but Hubble is allowing us to understand the complicated quasar morphology and galactic interactions in detail,” said lead author Ren.

“In the future, looking further at 3C 273 in infrared light with the James Webb Space Telescope might give us more clues,” said Ren.

The post Hubble Gets its Best Look At the First Quasar appeared first on Universe Today.

Eventually I will post all the talks, pro and con, at the Oxford Union’s debate on November 28, whose topic was this:

“This House Believes Israel Is an Apartheid State Responsible for Genocide.”

Speaking against the motion here is Jonathan Sacerdoti, identified by Wikipedia as

“a British broadcaster, journalist, and TV producer. He covers stories relating to the United Kingdom and Europe, as well as terrorism and extremism stories, race relations, Middle East analysis and the British royal family.  He is also a campaigner against antisemitism.”

His father was a survivor of the Holocaust.

I wanted to put this speech up now because it is uncensored, showing the abuse to which the pro-Israel speakers were subject, an abuse not evident in what was apparently a censored clip of Natasha Hausdorff’s speech the other day. I think it likely that this clip will be taken down, for it makes the Oxford Union look really really bad. 

This video, complete with unceasing shouts and attacks on the speaker, shows how shameful the audience really was, a shame that also devolves upon the Union’s moderators, who were clearly on the side of the proposition although they are supposed to be neutral. They do very little to quell the audience’s despicable treatment of the speakers.  Should not repeated abusers be ejected?

As you know, the proposition passed by a large proportion, with the audience packed with those who hate Israel, and with Jewish students apparently afraid to attend.

Sacerdoti’s arguments are good, and similar to Hausdorff’s, but of course he didn’t have a snowball’s chance in hell with an audience like that.

Have a listen, even if you don’t care much about the arguments, for this is, after all, supposed to be one of the most well-run and respected groups at Oxford University.

msn quotes Hausdorff on the abuse dished out in Arabic:

She detailed how Arab speakers on her team were subjected to abuse in Arabic, which she only learned about after the event.

“They were called ‘traitors’ and ‘collaborators’,” she said. “One of the speakers confided in me that the nature of that abuse and the threats have him flashbacks to a time he was targeted for being a collaborator in the West Bank.”

Pretrained large-scale AI models need to 'forget' specific information for privacy and computational efficiency, but no methods exist for doing so in black-box vision-language models, where internal details are inaccessible. Now, researchers addressed this issue through a strategy based on latent context sharing, successfully getting an image classifier to forget multiple classes it was trained on. Their findings could expand the use cases of large-scale AI models while safeguarding end users' privacy.

Fences are an effective stationary method of corralling livestock, but their sharp borders can create sudden changes in native grassland vegetation and the pollinators and birds that live there. Virtual, GPS-based fences may be the nature-friendly future of fencing, creating more natural grassland habitat, finds new research.

Dust storms on Mars could one day pose dangers to human astronauts, damaging equipment and burying solar panels. New research gets closer to predicting when extreme weather might erupt on the Red Planet.

Physicists have devised an algorithm that provides a mathematical framework for how learning works in lattices called mechanical neural networks.

Physicists have devised an algorithm that provides a mathematical framework for how learning works in lattices called mechanical neural networks.

To help improve punctuality by understanding how delays propagate and identifying critical trains, researchers have developed a new network-based method.

To help improve punctuality by understanding how delays propagate and identifying critical trains, researchers have developed a new network-based method.

Modeling how cars deform in a crash, how spacecraft responds to extreme environments, or how bridges resist stress could be made thousands of times faster thanks to new artificial intelligence that enables personal computers to solve massive math problems that generally require supercomputers.

Modeling how cars deform in a crash, how spacecraft responds to extreme environments, or how bridges resist stress could be made thousands of times faster thanks to new artificial intelligence that enables personal computers to solve massive math problems that generally require supercomputers.

Consumers' real-world stop-and-go driving of electric vehicles benefits batteries more than the steady use simulated in almost all laboratory tests of new battery designs, a new study finds.

A pioneering artificial intelligence (AI) powered model able to understand the sequences and structure patterns that make up the genetic 'language' of plants, has been launched by a research collaboration.

Could a decades-long debate about the mysterious movements of stars in Omega Centauri, the largest star cluster in the Milky Way, finally be resolved?

Scientists have developed the first electrically pumped continuous-wave semiconductor laser composed exclusively of elements from the fourth group of the periodic table -- the 'silicon group'. Built from stacked ultrathin layers of silicon germanium-tin and germanium-tin, this new laser is the first of its kind directly grown on a silicon wafer, opening up new possibilities for on-chip integrated photonics.

Photonic space-time crystals are materials that could increase the performance and efficiency of wireless communication or laser technologies. They feature a periodic arrangement of special materials in three dimensions as well as in time, which enables precise control of the properties of light. Scientists have shown how such four-dimensional materials can be used in practical applications.

Photonic space-time crystals are materials that could increase the performance and efficiency of wireless communication or laser technologies. They feature a periodic arrangement of special materials in three dimensions as well as in time, which enables precise control of the properties of light. Scientists have shown how such four-dimensional materials can be used in practical applications.

We tie our shoes, we put on neckties, we wrestle with power cords. Yet despite deep familiarity with knots, most people cannot tell a weak knot from a strong one by looking at them, research finds.

New observations from the James Webb Space Telescope suggest that a new feature in the universe -- not a flaw in telescope measurements -- may be behind the decade-long mystery of why the universe is expanding faster today than it did in its infancy billions of years ago.

Computer memory could one day withstand the blazing temperatures in fusion reactors, jet engines, geothermal wells and sweltering planets using a new solid-state memory device developed by a team of engineers.