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Webb Telescope Spots Full Einstein Ring


Einstein Ring, JWST-ER1, original and magnified. Image: NASA/JWST

NASA’s James Webb telescope has found the most beautiful Einstein Ring ever. An Einstein Ring is a phenomenon produced by gravitational lensing, when light from one object is bent around another one. Usually the two objects are different galaxies and most of the time we don’t see a full ring but rather several dots or arcs. But if the configuration coincidentally happens to be particularly symmetric – as in this case – we see a ring. The galaxy in the center of the new Einstein Ring that’s causing the lensing is an elliptic galaxy about 10 billion light years away and about 650 billion times as massive as our Sun.

Besides looking spectacular, gravitational lenses are also useful because they allow astrophysicists to infer the mass of the bending object, including its dark mass. Paper here.

New 3D Simulation of Supernova

Image: Ke-Jung Chen et al, ApJ (2023).

An international team of astrophysicists has recently created a high-resolution 3D simulation of supernovae that uses the most sophisticated fluid and gas dynamics to date. They looked at the collapse and following explosions of supermassive stars over a hundred times bigger than our sun with a new code called “CASTRO”.

Supernovae simulations are incredibly computationally intensive because of their chaotic nature and the sheer size of the system. Even using the Minnesota Supercomputing Institute, the simulation took over 50,000 computer hours to complete. The new simulation provides unprecedented information into the gas turbulence and energetics in supernovae, as well as the mixing of elements and creation of new elements in the supernova process. While the simulation is visually stunning and scientifically interesting, it is certainly not the first 3D supernova simulation, as some outlets claimed. Paper here.

3D-Printed Nerve Cells Create Brain-Like Networks


Image Credit: Yao et al., Advanced Healthcare Materials (2023)

Bio-engineers at Monash University have successfully used “bio-ink” to 3D-print nerve networks that mimic the human brain. The bio-ink is a gel that contains living cells (from rat brains) as well as non-cellular materials. The researchers printed the inks in an arrangement mimicking patterns of grey and white matter typically seen in the brain’s cortical structure. The printed networks displayed spontaneous neuron signals and responded to electrical stimulation. Press release here, paper here.

Comments

Matthias Urlichs

Oh, a mention of dark mass with no "if it exists" right after it? You're slacking off.

Anonymous

Pair-instability-supernova = hypernova? The ring...!

Anonymous

Those people who developed a procedure to see what happens when a giant star goes supernova maybe should look into what Betelgeuse is up to.

Anonymous

For much of my life, time after time, someone has found confirmation of something predicted by General Relativity, such as these "Einstein Rings." (Yes, that guy.) By people who actually dared solve the six independent differential equations of the tensor field equation. I once met, when working on a related project with a group at Stanford developing the main sensor for Gravity Probe-B, a NASA satellite mission meant to test two of General Relativity predictions (and it was a struggle, but it did confirm both!), a man who had just come up with a closed expression for the relatively weak field of something like the terrestrial homogeneous oblate spheroid, the geodetic "reference" one that is the best ellipsoidal fit to our planet. His name was Ronald J. Adler (*). Unfortunately he was dying of cancer and it was difficult to strike the appropriate note in casual conversation so as not to discourage him even more. As I remember it, Prof. Francis Everett gave a moving eulogy when it was all over for Ronald; I was back in Maryland at the time. (*) "Metric for an Oblate Earth", Ronald J. Adler, in "General Relativity and Gravitation", Vol. 31, No. 12, 1999. Requiescat in Pace, R.J.A.

Anonymous

Alas, different physics -- supernova modelers look at fluid flow and shock structures in a magnetized plasma starting from core instability. The phenomena that are observed around evolved red giant/asymptotic giant stars are tied to fusion rates in the star driving mass outflow mitigated by opacity. Dust formation is common in both environments, but even the most complete code in each case just models dust as a regulating knob in the code -- a quashing parameter that they set at various values for each run of the code. Other than dust, there are no real overlaps in the physics modeled by each code. If you're real interested in Betelgeuse, check out Eta Carinae, which has experienced massive eruptive outflows in the past and may be closer to going supernova.

Anonymous (edited)

Comment edits

2023-09-29 00:37:24 Tracey, Betelgeuse, it has been reported, is considered a serious candidate now for going supernova, if sadly no soon enough for any of us to live to see this, based on recent observations: https://www.scientificamerican.com/article/betelgueses-brightening-raises-hopes-for-a-supernova-spectacle/ I do appreciate your explanation about one detail of (I think) how the computer-implemented procedure mentioned by Sabine is used. But, while recently this star got darker because, it is thought, of a big belch of dust, this is not about that darkening, but about its recent 50% brightening after that darkening.
2023-09-28 20:46:31 Tracey, Betelgeuse, it has been reported, is considered a serious candidate now for going supernova if, sadly, not soon enough for any of us to live to see this, based on recent observations: https://www.scientificamerican.com/article/betelgueses-brightening-raises-hopes-for-a-supernova-spectacle/ I do appreciate your explanation about one detail of (I think) how the computer-implemented procedure mentioned by Sabine is used. But, while recently this star got darker because, it is thought, of a big belch of dust, this is not about that darkening, but about its recent 50% brightening after that darkening.

Tracey, Betelgeuse, it has been reported, is considered a serious candidate now for going supernova if, sadly, not soon enough for any of us to live to see this, based on recent observations: https://www.scientificamerican.com/article/betelgueses-brightening-raises-hopes-for-a-supernova-spectacle/ I do appreciate your explanation about one detail of (I think) how the computer-implemented procedure mentioned by Sabine is used. But, while recently this star got darker because, it is thought, of a big belch of dust, this is not about that darkening, but about its recent 50% brightening after that darkening.

Anonymous (edited)

Comment edits

2023-09-29 06:43:36 Here is a video with Feynman arguing for the often useful practice of thinking about somehing that really matters from "another point of view": https://www.youtube.com/watch?v=GNhlNSLQAFE The "quarks" part is out o date, as are two or three other things, because this is an old video, but the basic message is forever.
2023-09-28 22:51:21 Here is a video with Feynman arguing for the often useful practice of thinking about somehing that really matters from "another point of view": https://www.youtube.com/watch?v=GNhlNSLQAFE The "quarks" part is out of date, as are two or three other things, because this is an old video, but the basic message is right forever.

Here is a video with Feynman arguing for the often useful practice of thinking about somehing that really matters from "another point of view": https://www.youtube.com/watch?v=GNhlNSLQAFE The "quarks" part is out of date, as are two or three other things, because this is an old video, but the basic message is right forever.

Anonymous

Hi Oscar, grumpy stars are so difficult to predict. We've been waiting for Eta Carinae and a few others just like it (e.g. P Cygni) to go boom for a while. These guys are all burning elements heavier than helium in their core and are much further along in their evolution than Betelgeuse, which is currently burning helium in its core. Having said that, no one expected SN1987A because its progenitor star didn't show significant signs of the farting/belching that evolved stars do -- see Eta Car's giant eruption of 1837, which dwarfs whatever Betelgeuse has been up to of late. It's a bit of a crap shoot as to predicting when stars will blow up. The timescale for subsequent rounds of fusion from helium up to iron in the cores of massive stars is quite variable but we do know that the more massive a star is, the faster it burns through its fuel. The most massive stars don't even progress all the way to iron in their cores, they have so much gravitational potential energy that, when carbon burning ends, for example, the core collapses rather than starts a new round of fusion of the next higher elements. Who knows, maybe Betelgeuse will pop its cork before Eta Car, but my money is on Eta Car first just because it is far more massive and has already progressed beyond helium burning. Grumpy stars all have their own unique personalities which make them so much fun to observe! Betelgeuse deserves its time in the spotlight, but it is a bit of hype to say that it has moved near the front of the line for expected supernovae. Eta Car deserves some love too -- it was the 2nd brightest star in the sky (after Sirius) for a while after its great eruption.

Anonymous

Tracey, Thanks for taking the time to expatiate on the explosions of stars likely to go Boom! some time in the not too distant future, at least on a shorter than geological time scale. This has served my purpose too, when I made that short comment you initially responded to. Quite frankly, I am not interested all that much on the method for modelling, simulating, emulating, or whatever, what goes on inside stars, which might include, I suppose, those also ripe to explode, brought up by Sabine. I was more interested into trying to bring attention on what has been coming out repeatedly in science news, of late, about Betelgeuse, and read what someone might have to say about that, as you just did. I did not think it necessary to explain exactly what was the matter with Betelgeuse that I had in mind. Maybe I should have. (Besides, I think that, as pronounced in English, "Betelgeuse" is a funny name.)

Anonymous

Tracey: "It´s a bit of a crap shoot as to predicting when stars will blow up." -- Same with earthquakes, volcanos and so on.

Anonymous

Volcano eruptions tend to announce themselves with a prolonged series of small "harmonic" tremors that are used to set off alarms, sometimes with days of anticipation (as long as someone is watching and gives the alarm). Earthquakes are quite another story. I knew someone who told me with complete self-assurance, years ago, that earthquakes were a few years away from being totally predictable, made a big deal of how he was going to be able to predict earthquakes with GPS measurements of the precursor changes of shape in the Earth's crust, and even was the main protagonist of an IMAX screen documentary on the subject. Well, he did not get any results worth mentioning, neither did those who looked into emissions of gases, changes in electric or magnetic fields and several other such ideas. Since the days of the Han Dynasty, in the Second Century AD, there have been seismometers that can detect the occurrance of strong earthquakes and, with a network of several of them, figure out more or less how strong and where they have taken place. And there is, now days, enough understanding of the geological conditions that favor them as well as how to interpret measurements with, yes, GPS, GALILEO, etc., plus clinometers, strain meters and such to guess, very roughly, the likelihood of a large earthquake sometime in the next X years, with X > 10 usually. And there things stand for now. See also: https://engines.egr.uh.edu/episode/324# about ancient Chinese seismometers.