Science

A stellar odd couple 700 light-years away is creating a chaotically beautiful display of colourful, gaseous filaments. The Hubble captured the pair, named R Aquarii, and their symbiotic interactions. Every 44 years the system’s violent eruptions blast out filaments of gas at over 1.6 million kilometers per hour.

R Aquarii consists of two dramatically different types of stars: a white dwarf and a particular type of variable star.

The white dwarf is a stellar remnant. It’s what remains of a main sequence star that’s reached the end of its life of fusion. It shines only because of its remnant heat. White dwarfs are extremely dense, so even though they’re about the same size as Earth, they have a mass similar to the Sun. That means for such a small volume object, they exert a powerful gravitational pull.

The variable star is a type of red giant called a Mira-type variable. It’s a complete opposite to its companion star. Rather than extremely compact and dense, the red giant is bloated and red. It’s more than 400 times larger than the Sun. It’s a pulsating giant star that’s more at home atop Sauron’s Dark Tower than it is in a catalogue of stars. As it pulses, it changes temperature and luminosity. Over an approximately 390-day period, its brightness changes by a factor of 750.

That means that when the star is at its peak brightness, it’s more than 5,000 times as bright as our Sun.

This image of R Aquarii is from the SPHERE planet-hunting instrument on the ESO’s Very Large telescope in 2018. It was captured while the instrument was being tested, and astronomers were able to capture dramatic details of the turbulent stellar relationship with unprecedented clarity. This image is from the SPHERE/ZIMPOL observations of R Aquarii, and shows the binary star itself, as well as the jets of material spewing from the stellar couple. Image Credit: By ESO/Schmid et al. – https://www.eso.org/public/images/eso1840a/, CC BY 4.0, https://commons.wikimedia.org/w/index.php?curid=75014181

The powerful pulsing of this massive red star is enough to be a spectacle in itself. But it’s relationship with its binary partner creates an even more spectacular display. As the two orbit, the dense white dwarf draws hydrogen gas away from the red giant. The hydrogen accumulates on the white dwarf until the star can’t take it anymore. Then the hydrogen explodes in nuclear fusion on the surface of the small, dense star.

The nova explosion ejects the material into space in gaseous filaments. But the region around white dwarfs is dominated by the star’s powerful magnetic fields, which can be millions of times stronger than Earth’s. The force of the nuclear explosion and the magnetic fields twist the gaseous hydrogen filaments into trails and streamers, and eventually, they loop back on themselves and form spiral patterns.

We can only see this nebula of gaseous filaments because the radiation from both stars strips electrons from the hydrogen, turning it into ionized gas. The ionized hydrogen glows brightly and creates a beautiful natural display.

The central binary star’s brightness changes over time because of the pulsing of the red giant. The gas appears red to us, but not because of the red giant. R Aquarii is in a dusty region, and the dust absorbs all the blue light, with only red reaching us.

A Hubble timelapse consisting of five images of R Aquarii from 2014 to 2023 helps bring the dynamic interplay to life.

Looking at these images, it’s easy to misunderstand the scale of the stars, the nebula, and the brightly-lit, filaments of ionized hydrogen. However, the material blasted into space reaches as far as 400 billion kilometers (248 billion miles). For comparison, that’s about 24 times greater than our Solar System’s diameter.

R Aquarii was first observed by German astronomer Karl Ludwig Harding in 1810, when he was a colleague of Carl Friedrich Gauss at Gottingen Observatory. It’s one of the nearest symbiotic stars, and is an object that astronomers are very interested in observing. In the 20th century, Edwin Hubble and others studied it and recognized its complex interactions and the resulting nebula. R Aquarii and its brethren can teach astronomers a lot about stellar winds, accretion, and ionized nebula.

The post It Takes Very Special Conditions to Create This Bizarre Stellar Spectacle appeared first on Universe Today.

Just a brief note, in a very busy period, to alert those in the Providence, RI area that I’ll be giving a colloquium talk at the Brown University Physics Department on Monday November 18th at 4pm. Such talks are open to the public, but are geared toward people who’ve had at least one full year of physics somewhere in their education. The title is “Exploring The Foundations of our Quantum Cosmos”. Here’s a summary of what I intend to talk about:

The discovery of the Higgs boson in 2012 marked a major milestone in our understanding of the universe, and a watershed for particle physics as a discipline. What’s known about particles and fields now forms a nearly complete short story, an astonishing, counterintuitive tale of relativity and quantum physics. But it sits within a larger narrative that is riddled with unanswered questions, suggesting numerous avenues of future research into the nature of spacetime and its many fields. I’ll discuss both the science and the challenges of accurately conveying its lessons to other scientists, to students, and to the wider public.

In the earliest moments of the Universe, the first photons were trapped in a sea of ionized gas. They scattered randomly with the hot nuclei and electrons of the cosmic fireball, like tiny boats in a stormy sea. Then, about 370,000 years after the big bang, the Universe cooled enough for the photons to be free. After one last scattering, they could finally ply interstellar space. Some of them traveled across 14 billion years of space and time to reach Earth, where we see them as part of the cosmic microwave background. The remnant first light of creation.

The CMB is a central point of evidence supporting the Big Bang and the standard model of cosmology. By observing the scale of fluctuations within the CMB, we can measure things such as the shape of space, the distribution of matter and energy, and the rate of cosmic expansion. It’s that last one that has been troubling astronomers, thanks to the Hubble tension problem.

Astronomers have several ways to measure the Hubble parameter, the value of which tells us the rate of cosmic expansion. The methods generally fall into two types: those based on observations of the CMB, and those based on astrophysical phenomena such as supernovae. The problem is that these two types of methods don’t agree on the value. They even contradict each other, leading some astronomers to argue there must be something wrong with the standard model.

Polarization fluctuations within the CMB. Credit: SPT-3G Collaboration

Of the two types, the CMB method is the one with the most limited data. The best CMB observations we have come from space telescopes such as Planck, which measured fluctuations in CMB intensity. One solution to the tension problem would be to argue that the CMB observations are somehow biased. But new observations gathered by the South Pole Telescope (SPT) throw that idea out of the water.

Rather than measuring intensity fluctuations in the cosmic microwave background, the SPT observed variations in its polarization. All the CMB light we observe comes from a moment of last scattering, when photons scattered off an ion one last time before making the billion-year journey to reach us. When light is scattered, it is polarized relative to the distribution of ionized gas. So these observations are a truly independent measure of cosmic expansion.

Different modes of CMB polarization. Credit: Sky and Telescope

One challenge in working with polarized CMB data is that as the first light traveled through space, it interacted with matter, space, and time. Not only is the light red-shifted due to cosmic expansion, it is gravitationally lensed by galaxies, which changes the polarization. Some of the light scatters off interstellar gas, which gives a false polarization. Even ripples of gravitational waves can affect the light’s orientation. So the team looked at not just the raw polarization of the CMB, but also what are known as E-mode and B-mode polarization. Each of these is sensitive to different kinds of bias. For example, the E-mode is more sensitive to secondary scattering, while the B-mode is more sensitive to cosmic inflation and gravitational waves.

By combining and contrasting these polarization modes, the team was able to calculate a new value for the Hubble parameter. Since it isn’t based on intensity fluctuations, it is free of any bias in the space-based CMB observations. Based on their data, the team got a value of H₀ at 66.0–67.6 (km/s)/Mpc. This agrees with the intensity-based observations of WMAP and Planck, which found a value of 67–68 (km/s)/Mpc. In comparison, the astrophysical methods find a value of 73–75 (km/s)/Mpc.

This study confirms that earlier CMB observations are not biased. The Hubble tension is very real, and we currently have no clear way to resolve it.

Reference: SPT-3G Collaboration. “Cosmology From CMB Lensing and Delensed EE Power Spectra Using 2019-2020 SPT-3G Polarization Data.” arXiv preprint arXiv:2411.06000 (2024).

The post A New Look a the Most Ancient Light in the Universe appeared first on Universe Today.

Scientists have created a new 'biocooperative' material based on blood, which has shown to successfully repair bones, paving the way for personalised regenerative blood products that could be used as effective therapies to treat injury and disease.

A sprinkling of magnetic nanoparticles is just enough to power up catalysts, so they can make hydrogen peroxide production more efficient.

Animals and plants also live and thrive on public squares. This creates opportunities for greater biodiversity and well-being for the human population. Researchers have studied at 103 locations in Munich how various factors affect flora and fauna. They advocate a close examination of local conditions and a more nature-focused approach to the design of public spaces.

Scientists have produced a new route to materials with complex 'disordered' magnetic properties at the quantum level. The material, based on a framework of ruthenium, fulfils the requirements of the 'Kitaev quantum spin liquid state' -- an elusive phenomenon that scientists have been trying to understand for decades.

Metamaterials are artificial materials that do not occur in nature. Their components function like atoms in conventional materials but have special optical, electrical and magnetic properties. Interaction between the components is crucial to a metamaterial's functionality. Previously a component could usually interact only with its immediate neighbors. Researchers have now developed a mechanical metamaterial with which these interactions can also be triggered at greater distances within the material. Potential uses of the material include measuring forces and structural monitoring.

A simple, highly efficient, inexpensive, and environmentally friendly process could provide a viable pathway for the sustainable recycling of depleted lithium-ion batteries (LIBs): No chemicals beyond citric acid need to be added to leach out and separate over 99 % of the lithium, nickel, cobalt, and manganese metals contained in NCM batteries. The resulting recycled material can be directly converted into NCM electrodes, reports a research team.

I have never singled out a single factor that I considcered crucial in Trump’s victory against Harris, because there were so many factors in play. These include immigration, the economy, wokeness among Dems (loudly decried by Trump’s ads), Harris’s failure to choose Josh Shapiro as a running mate, Biden’s failure to resign, the word-salady nature of Harris’s campaign and her refusal to answer questions like “How would your administration differ from Biden’s?”, and, of course, the blame people affix to Republicans, saying that they are simply misogynistic, stupid, and nationalistic yokels.  A change in any of these factors might have changed the election’s results, but, in truth, we don’t know. All we can offer is post facto analyses. That’s why I simply post a diversity of takes so readers can hear all viewpoints.

In response to one public post I recently put on Facebook about Laura Helmuth leaving Scientific American after going on an expletive-laden post-election rant that demonized Trump voters as “fucking fascists”, as well as “mean, dumb, and bigoted,” I got one comment that basically agreed with Helmuth:

I think the outcome of the election was abysmal, dreadful, and maybe the trans activists were a small part of the problem, but a much bigger problem is the poor state of American education and the country’s persistent religiosity. Again, not the fault of the left.

In other words, this commenter agreed with Helmuth, throwing into the mix the high religiosity of Americans.  I haven’t talked to enough people in my elite “bubble” to know how pervasive this feeling is.

In the 38-minute video below, a segment of Dan Senor’s “Call Me Back” show, New York freshman Democratic Congressman Ritchie Torres, only 36, says that the Democratic left basically scuppered the election by infusing the party with progressive ideology, refusing to address the two issues that really mattered to the middle- and lower-class voters: immigration and inflation. Torres represents the South Bronx, and his district is characterized by Wikipedia as “by one measure the poorest congressional district in the United States.”

A couple of quotes from Torres:

“My diagnosis is that we have to Stop pandering to a far left that is more representative of Twitter and Tik Tok than it is to the real world  and start listening to working-class people of color—working class people in general—who have historically been the heart and soul of the Democratic Party.”

“The movement of ‘defund the police’ has done almost irreparable damage to the brand of the Democratic Party. . . . if the objective is to win elections in the real world, then we have to marginalize the far left in favor of working class Americans.”

Torres is not hesitant to criticize Biden or Harris, calling Biden’s actions on immigration “political malpractice”, which aroused clear signs of popular discontent well before the election.

Senor, who comes from a Jewish background, then brings up an issue that most commenters have neglected: the Jewish vote. As he notes, Jewish voters went for the GOP in higher proportions than previously, so that in this election Jewish voters were largely “up for grabs”—unsure about how to vote. Slogans from the far left like “globalize the intifada,” or “from the river to the sea,” says Torres, alienated Jewish voters, most of whom support Israel.

Torres theorizes that the Jewish vote may have been decisive in states like  Michigan, Georgia, and Arizona, all of whom went for Trump. He adds that the says far left “chose to wage an antisemitic smear campaign in an attempt to sabotage Josh Shapiro, simply because he was a Jew who spoke out against the antisemitism after October 7. . . . The far left’s hatred for Donald Trump was exceeded only by its hatred for Israel and for any Jew who identifies unequivocally as pro Israel. And that to me was the ultimate example of how destructive the far left can be to our ability to win elections.”

Torres argues that Harris herself wasn’t anti-Israel, but a mainstream, pro-Israel centrist who was falsely painted as anti-Israel by the far left. Nevertheless, as you may know, Harris talked out of both sides of her mouth, always mentioning the suffering of Palestinian people when she defended Israel. As Senor says, Harris was, on the Gaza War, talking out of both sides of her mouth to appeal to both sides.  Senor argues that this kind of moral equivalency, or moral equivocation, cost Harris Jewish votes.

Torres chimes in eloquently, saying that in all politics, candidates must espouse “moral clarity”, and Jews didn’t feel Harris’s pious mouthings “in their kishkes“. (Torres gets extra points for the Yiddish.)

30 minutes in, Torres goes on an eloquent tear, including stuff like this:

“The fact that the far left would wage an antisemitic smear campaign against the most popular governor of the most pivotal swing state: that should have been a wake-up call that the far left is  willing to sacrifice what is best for the Democratic party on the altar of ideological purity and anti-Zionism.”

Senor adds that pro-Hamas and anti-Israel protests weren’t just a Jewish issue—that others look at people celebrating Hamas and Hezbollah and get turned off by the far left.  Torres thinks that the failure to deal with such protests undercut Americans’ sense of safety and convinced them that government cannot keep people safe. This, he sayus, was an indictment of the governments of both New York State and New York City.

In the end, since people of color, both middle-class and impecunious ones, are Torres’s constituents, he concludes that, at least in his district, the cost of living far, far outweighed their concern for a war 5,000 miles away.

I recommend this video not because it gives the reason why the Democrats were routed, but why they were routed in a poor, black district. And, to me at least, having sympathies for Israel, it makes Torres look like a guy with an exceedingly bright future in Democratic politics.

Watch it!

Letting AI models communicate with each other in their internal mathematical language, rather than translating back and forth to English, could accelerate their task-solving abilities

Governments and companies almost never take action when satellites alert them about large methane leaks coming from oil and gas infrastructure

Water levels in the Caspian Sea are set to fall dramatically as the climate gets hotter, posing a major threat to economic activity and ecosystems in the region

Space tourism here is here to stay, and will likely remain a permanent fixture of near-Earth activities for the foreseeable future. But is it worth it? 

While for decades private individuals have been able to negotiate with national space agencies to get rides to the International Space Station, it wasn’t until the advent of private aerospace that many more opportunities opened up. With wealthy billionaires like Elon Musk, Jeff Bezos, and Richard Branson all creating their own rocket companies, it changed the playing field. Now if you are a private individual wanting to take a hop into space you can shop around with a lot more options.

While Elon Musk’s SpaceX does not have a stated goal of space tourism, if you are willing to front the money you can get a ride on a Crew Dragon capsule, like Jared Isaacman recently did with his Polaris Dawn mission. On the other end of the spectrum, Richard Branson’s Virgin Galactic is explicitly designed around space tourism. They offer short sub-orbital hops for a few hundred thousand dollars each.

Space tourism certainly has several positives. For one there is more interest and activity in space which generally brings positive attention to the industry. Second, by companies chasing after a new market niche, these companies are developing new technologies and approaches which can have further beneficial effects on the larger industry. Lastly, there’s the well-reported “overview effect” where people finally get a view of our fragile home planet and gain a new perspective on what is important in human life.

On the other hand, it’s not exactly like many people get to be space tourists. Even the cheapest tickets are comparable to the cost of a home, making it inaccessible to all but the wealthiest people in our society. So it’s not like many people are getting to appreciate the view or participate in this new market. In fact, space tourism can lead to negative feelings as people just think of space as the province of the rich and elite.

Lastly, there are precious few dollars available for rocket development and space exploration. Many might argue that these dollars would be better suited to scientific exploration or experimental development of new technologies rather than creating a new pastime for the ultra wealthy.

Ultimately space tourism is going to be a thing whether we like it or not. It’s also not going to be a big thing. For the foreseeable future it will remain incredibly expensive, and most rocket companies are more interested in scientific and industrial pursuits in low-Earth orbit and beyond. So either way, whether it’s a good or bad thing, it’s simply not going to make a huge difference.

The post Space Tourism: The Good, The Bad, The Meh appeared first on Universe Today.

A genetic flaw dooms half of all crested newts to die before they hatch – now we know how this baffling evolutionary quirk came about

Two massive galaxies are bending light from the same distant quasar, creating a so-called Einstein zigzag lens that could help astronomers pin down how quickly the universe is expanding

It has been 50 years since archaeologists discovered Lucy, perhaps the most famous ancient hominin ever found. But the scientists who have studied her say that this fossil gave us a misleading image of the nature of her species

A classic study found that people can fail to notice a gorilla when they are focusing on something else, but new experiments suggest this "inattentional blindness" might not tell the whole story

When RFK Jr. does to the U.S. what he did to Samoa, doctors will say they are horrified, that they love vaccines, blah blah blah. But it will be too late.

The post If You Sanewashed RFK Jr., Or If You Sanewashed Doctors Who Did, You Own the Next 4 Years first appeared on Science-Based Medicine.

In 1960, in preparation for the first SETI conference, Cornell astronomer Frank Drake formulated an equation to calculate the number of detectable extraterrestrial civilizations in our Milky Way. Rather than being a scientific principle, the equation was intended as a thought experiment that summarized the challenges SETI researchers faced. This became known as the Drake Equation, which remains foundational to the Search for Extraterrestrial Intelligence (SETI) to this day. Since then, astronomers and astrophysicists have proposed many updates and revisions for the equation.

This is motivated by ongoing research into the origins of life on Earth and the preconditions that led to its emergence. In a recent study, astrophysicists led by Durham University produced a new model for the emergence of life that focuses on the acceleration of the Universe’s expansion (aka. the Hubble Constant) and the number of stars formed. Since stars are essential to the emergence of life as we knot it, this model could be used to estimate the probability of intelligent life in our Universe and beyond (i.e., in a multiverse scenario).

The study was led by Daniele Sorini, a postdoctoral Research Associate at Durham University’s Institute for Computational Cosmology, and was funded by a European Research Council (ERC) grant. She was joined by John Peacock, a Professor of Cosmology at the Royal Observatory and the University of Edinburgh’s Institute for Astronomy, and Lucas Lombriser, from the Département de Physique Théorique, Université de Genève. The paper that details their findings was recently published in the Monthly Notices of the Royal Astronomical Society.

The Drake Equation is a mathematical formula for the probability of finding life or advanced civilizations in the universe. Credit: University of Rochester

As noted, the Drake Equation was not intended as a tool for estimating the number of extraterrestrial intelligences (ETIs) but as a guide for how scientists should search for life in the Universe. The formula for the equation is:

N = R* x fp x ne x fl x fi x fc x L

Whereas N is the number of civilizations in our galaxy that we might able to communicate with, R* is the average rate of star formation in our galaxy, fp is the fraction of those stars that have planets, ne is the number of planets that can actually support life, fl is the number of planets that will develop life, fi is the number of planets that will develop intelligent life, fc is the number civilizations that would develop transmission technologies, and L is the length of time that these civilizations would have to transmit their signals into space.

In the same sense, the new research does not attempt to calculate the absolute number of intelligent species in the Universe. Instead, the team presents an analytical model for cosmic star formation history to measure the impact of cosmological parameters within the most widely accepted cosmological model. This is none other than the Lambda-Cold Dark Matter (LCDM) model, where Dark Matter and Dark Energy (Lambda) account for roughly 95% of the matter-energy density of the Universe. The remaining 5%, the “ordinary” matter we see every day, is what scientists refer to as baryonic matter (aka. “luminous matter”).

In their paper, the team calculated the fraction of ordinary matter that is converted into stars over the entire history of the Universe based on different Dark Energy densities. Stars are essential to life, creating heavier elements through nuclear fusion that allow for planet formation, biochemistry, and all life as we know it. Their model predicts that the most efficient density for star formation would be 27%, compared to 23% scientists have observed in our Universe. In short, their results suggest that our Universe is an outlier in the context of the multiverse.

Early Dark Energy could have caused early seeds of galaxies (depicted at left) to sprout many more bright galaxies (at right) than theory predicts. Credit: Josh Borrow/Thesan Team

These findings could have significant implications for cosmology and the ongoing debate about whether or not our Universe is “fine-tuned” for life. As Dr. Sorini explained in a Royal Astronomical Society press release:

“Understanding Dark Energy and the impact on our Universe is one of the biggest challenges in cosmology and fundamental physics. The parameters that govern our Universe, including the density of dark energy, could explain our own existence. Surprisingly, though, we found that even a significantly higher dark energy density would still be compatible with life, suggesting we may not live in the most likely of Universes.”

The new model could also provide insight into how differing densities of Dark Energy affect the formation of the Universe and the development of conditions that allow life to emerge. The influence of Dark Energy drives cosmic expansion, causing the large-scale structures of the Universe (galaxies and galaxy clusters) to move farther and farther apart. For life to develop, matter must be able to clump together to form stars and planets and remain stable for billions of years – since evolution is a long-term process lasting billions of years.

Another takeaway from this research is that star formation and the evolution of the large-scale structure of the Universe achieve a balance over time. This balance determines the optimal value of Dark Energy density needed for the emergence of life and the eventual development of intelligent life. Said Prof. Lombriser: “It will be exciting to employ the model to explore the emergence of life across different universes and see whether some fundamental questions we ask ourselves about our own Universe must be reinterpreted.”

The Drake Equation may need additional parameters, including a Lambda energy density (ld) and a multiverse (mv) parameter. Regardless, the search for life and the question of how it can arise endure, much like Frank Drake’s equation itself!

Further Reading: Royal Astronomical Society, MNRAS

The post New Study Examines Cosmic Expansion, Leading to a New Drake Equation appeared first on Universe Today.