Science

Computer simulations by astronomers support the idea that dark matter -- matter that no one has yet directly detected but which many physicists think must be there to explain several aspects of the observable universe -- exists, according to the researchers.

The research explores how CRISPR can be used to edit RNA.

On 9 January 2024, the Einstein probe was launched, its mission to study the night sky in X-rays. The first image from the probe that explores the Universe in these energetic wavelengths has just been released. It shows Puppis A, the supernova remnant from a massive star that exploded 4,000 years ago. The image showed the expanding cloud of ejecta from the explosion but now, Einstein will continue to scan the skies for other X-ray events. 

The Chinese and European probe was designed to revolutionise our understanding of the Universe in X-rays. Named after none other than Albert Einstein, it houses cutting edge technology that will enable the observation of black holes, neutron stars and other events and phenomena emitting X-ray radiation. To achieve this it has two science instruments on board; the Wide-field X-ray Telescope (WXT) to give large field views of the sky and the Follow-up X-ray Telescope (FXT) which homes in on objects of interest identified by WXT.

The Einstein probe has three main questions it hopes to address focusing on black holes, gravity waves and supernovae. The recent image just released shows the stunning Puppis A supernova remnant. Supernova are a common process that takes place at the end of a massive star’s life. A star like the Sun is fusing hydrogen in its core into helium. The process is known as thermonuclear fusion and it releases heat, light and an outward pressure known as the thermonuclear force. While a star is stable, the thermonuclear force balances the force of gravity which is trying to collapse the star. 

Massive stars will continue fusing different elements in the core until an iron core remains. It’s not possible to fuse iron so the thermonuclear force ceases allowing gravity to win. the core collapses and the inward rushing material crashes down onto the core and rebounds into a massive explosion known as a supernova. 

Puppis A is one such object that is thought to have exploded 4,000 years ago. It lies about 7,000 light years from us which means the light that the radiation detected by the Einstein probe left about 7,000 years ago. 

In the image released from Einstein, the cloud like structure is all that remains of the star that went supernova. It is possible to see a bright dot at the centre of the cloud, this is the core of the star that remains, a neutron star. The FXT image was accompanied by a spectrum to show the distribution of energy to help understand the elements present. 

Source : Supernova remnant Puppis A imaged by Einstein Probe

The post First Light from Einstein Probe: A Supernova Remnant appeared first on Universe Today.

Anyone familiar with astronomy will know that galaxies come in a fairly limited range of shapes, typically; spiral, elliptical, barred-spiral and irregular. The barred-spiral galaxy has been known to be a feature of the modern universe but a study from astronomers using the Hubble Space Telescope has recently challenged that view. Following on observations using the James Webb Space Telescope has found the bar feature in some spiral galaxies as early as 11 billion years ago suggesting galaxies evolved faster in the early Universe than previously expected. 

Our own Galaxy, the Milky Way is a spiral galaxy with a central nucleus and spiral arms emanating out from the centre. Our Solar System lies about 25,000 light years from the centre. Look at the galaxies in the sky though and you will see a real mix but generally they fall under the four main categories. Edwin Hubble tried to bring some structure to the different shapes by developing his galaxy classification scheme to articulate not only the shape but also the sub categories within them. 

This research published in Nature is the first direct confirmation that supermassive black holes are capable of shutting down galaxies

It has been known for some time that galaxies aren’t static. They move and they evolve and change. Spiral galaxies for example, as they age, they often develop a bar feature. The bar joins up the spiral arms instead of a nucleus connecting them and it is believed they are temporary, forming when a build of gas creates a burst of star formation. 

The existence of a bar in a spiral galaxy suggests that the galaxy is fairly stable. Understanding just how the bar feature forms is key to understanding the evolutionary process of the galaxy itself. All previous observations showed that the appearance of the bar significantly reduces from the nearby Universe to redshifts near a value of one. This tells us that the bar seemed to be a modern feature and not present in the early Universe. 

The barred spiral galaxy NGC 1300. Credit: NASA, ESA, and The Hubble Heritage Team (STScI/AURA)

In a new paper by lead author Zoe A Le Conte, observations from the more sensitive James Webb Space Telescope report that galaxies to greater redshift are studied for bar features. Data is used from the Cosmic Evolution Early Release Science Survey and the observations from the Public Release Imaging for Extragalactic Research studies. Only the galaxies that also appear in the Cosmic Assembly Near Infra Red Deep Extragalactic Legacy Survey are used giving a sample of 368 face on galaxies. 

The team visually searched through the 368 galaxy selection to classify and identify those with bars between redshifts 1 and 2 and then repeated the exercise for those between redshift 2 and 3. As expected, the fraction of bars reduced from around 17.8% between a red shift of 1 and 2 down to 13.8% at the greater red shift of 2 to 3. 

The study revealed that JWST’s infra-red sensitivity picked up twice as many barred-spiral galaxies than the HST’s more blue sensitive imaging platform. Le Conte and her team conclude that the evolution of bars in spiral galaxies began to appear at a much earlier epoch, around 11 billion years ago. 

Source : A JWST investigation into the bar fraction at redshifts 1 ? z ? 3

The post Galaxies Evolved Surprisingly Quickly in the Early Universe appeared first on Universe Today.

From Jerry: I spent about 45 minutes walking through the pro-Palestinian encampment this afternoon, listening and taking pictures.  I did not engage anybody save campus cops and deans and call.

The demonstration clearly violates both campus regulations and the law in several ways (I’ll show photos tomorrow, but see the Dean of Student’s email below.)

It blocks university sidewalks and thus impedes access to buildings

It is likely loaded with outsiders not from the University. I can’t tell this for certain, but I’ve been to a lot of pro-Palestinian demonstrations and don’t recognize most of the people. Any outsiders are therefore trespassing by camping out on University property.

The demonstration itself is almost certainly illegal, as it is taking up large amounts of space on the quad, depriving other students of using it. (This is an area where students like to sit, chat, or lie in the sun.) Further, one is not allowed to set up tents in the quad and sleep there overnight (see below).

There is chilling of speech. I heard one of the leaders announce, through a megaphone, something like “Do not talk to the press. Do not talk to deans on call, as they are no different from the police. And do not talk to Zionists.” I recorded some of this and will put up a movie tomorrow. The anti-Zionist trope is, of course, not only a form of anti-semitism, but a chilling of speech of any Jewish or pro-Israeli person who walks through the encampment. (I have never seen that protest leader before; I suspect he was sent in by some organization like SJP National.)

And yes, most of the tents look alike, implying that some organization funded their purchase or rental, or supplied them. There is a medical tent and lots of food and supplies, implying not only that this demonstration was well planned and funded, but that the protestors plan to be here for a long time.

I finally received a response from my email this morning to the Dean of Students asking what parts of this demonstration violate university regulations. It was a response not to me personally, but to the entire University community. Among the paeans to free expression, which I agree with, is this:

As part of our free expression principles, the University is fundamentally committed to upholding the rights of protesters to express a wide range of views. At the same time, University policies make it clear that protests cannot jeopardize public safety, disrupt the University’s operations, or involve the destruction of property.

Setting up tents on the Quad or erecting other structures and obstructions without prior approval, as happened in this case, is a violation of University policy and will result in disciplinary action. We are monitoring the situation closely. The individuals involved are on notice that the University is prepared to take further action in the event of continued violations of our time, place, and manner policies governing protests, threats to public safety, disruption of operations or academic activities, or destruction of property.

This is heartening, though I am not sure that these individuals really were put on notice. I’ll take the Dean’s word for it. What this means is that the participants, at least those who are U of C members, might be punished. We shall see.

The President of the University has sent out an incredibly ambiguous and waffling email implying that the demonstrators really are violating university policy but he’s not going to do anything about it right now, though he may in the future. I will reproduce that tomorrow morning. The Jewish students are incredibly upset with this statement, as am I. The Dean of Students has far more guts than our President.

In sum, our University won’t even follow its own regulations–regulations put in place to promote free speech–by preventing obstructive and illegal demonstrations. Nor will they even attempt to ascertain which participants belong in the University of Chicago community and which don’t.

Were I President, the first thing I would do is to send university police through the encampment, asking to see their U of Chicago IDs. If they have them, fine; leave them alone for the moment. But do take their names for purposes of University punishment (see above). For those without University IDs, make them leave campus, escorted by the police. This is a relatively peaceful and nonviolent way to initially deal with the demonstration. .

Speaking of the cops, I asked the University police (only a few were there) why they didn’t do anything. They said they couldn’t without orders from “above” (meaning the administration). I then grilled three “Deans on Call”, who are supposed to monitor the demonstration. I asked them what they were doing about the illegal bits of the demonstration. They said they could not do anything, not without “orders from above.” Again, that means the administration. Deans on Call are useless in these situations.

So far, then, we have an ambiguous email from the President and a harder-hitting one from the Dean of Students. Whether the University will really act to remove the encampment remains to be seen. After all, Columbia University was supposed to take down its encampment at 2 pm New York time yesterday. It is still there as of this evening. And I am not at all confident, based on previous episodes, that the illegally protesting students will be punished.

Stay tuned. Photos and video tomorrow. But this is incredibly time-consuming!

Researchers have developed a technique to move objects around with a jet of wind. The new approach makes it possible to manipulate objects at a distance and could be integrated into robots to give machines ethereal fingers.

Researchers have developed a technique to move objects around with a jet of wind. The new approach makes it possible to manipulate objects at a distance and could be integrated into robots to give machines ethereal fingers.

A bright yellow pigment favored a century ago by Impressionists such as Matisse and Van Gogh is losing its luster. Researchers have developed a laser imaging technique that can detect the first tiny signs of the pigment's breakdown before they're visible to the eye. The work could help art conservators take earlier steps to make the color last.

Plastic production is responsible for more greenhouse gas emissions than flying – at a summit in Canada, countries were divided on how to deal with this under-recognised part of the plastic problem

Red foxes and Arctic foxes dive headfirst into snow at up to 4 metres per second to catch small rodents, and the shape of their snouts reduces the impact force

When a spacecraft arrives at its destination, it settles into an orbit for science operations. But after the primary mission is complete, there might be other interesting orbits where scientists would like to explore. Maneuvering to a different orbit requires fuel, limiting a spacecraft’s number of maneuvers.

Researchers have discovered that some orbital paths allow for no-fuel orbital changes. But the figuring out these paths also are computationally expensive. Knot theory has been shown to find these pathways more easily, allowing the most fuel-efficient routes to be plotted. This is similar to how our GPS mapping software plots the most efficient routes for us here on Earth.

In mathematics, knot theory is the study of closed curves in three dimensions. Think of it as looking at a knotted necklace or a tangle of fishing line, and figuring out how to untangle them in the most efficient manner.

In the same way, a spacecraft’s path could be computed in a crowded planetary system – around Jupiter and all its moons, for example – where the best, simplest and least tangled route could be computed mathematically.

A graphic showing the orbital path the Danuri Lunar Pathfinder spacecraft will take to go into orbit around the Moon. Credit: Korea Aerospace Research Institute (KARI)

According to a new paper in the journal Astrodynamics, “Applications of knot theory to the detection of heteroclinic connections between quasi-periodic orbits,” using knot theory to untangle complicated spacecraft routes would decrease the amount of computer power or just plain guesswork in plotting out changes in spacecraft orbits.

“Previously, when the likes of NASA wanted to plot a route, their calculations relied on either brute force or guesswork,” said Danny Owen, a postgraduate research student in astrodynamics, in a press release from the University of Surrey. “Our new technique neatly reveals all possible routes a spacecraft could take from A to B, as long as both orbits share a common energy level.”

Owen added that this new process makes the task of planning missions much simpler. “We think of it as a tube [subway] map for space,” he said.

Spacecraft navigation is complicated by the fact that nothing in space is a fixed position. Navigators must meet the challenges of calculating the exact speeds and orientations of a rotating Earth, a rotating target destination, as well as a moving spacecraft, while all are simultaneously traveling in their own orbits around the Sun.

Since fuel is a limited resource for most missions, it would be beneficial to require the least amount of fuel possible in making any changes to the course of a spacecraft in orbit.  

Spacecraft navigators use something called heteroclinic orbits — often called heteroclinic connections — which are paths that allow a spacecraft to travel from one orbit to another using the most efficient amount of fuel – or sometimes no fuel at all. But this usually takes a large amount of computer power or a lot of time to figure out.  

Artist’s impession of the Lunar Gateway with the Orion spacecraft docked on the left side. Credit: ESA

But Owen and co-author Nicola Baresi, a lecturer in Orbital Mechanics at the University of Surrey, wrote that by using knot theory, they have developed “a method of robustly detecting heteroclinic connections,” they wrote in their paper, to quickly generate rough trajectories – which can then be refined. This gives spacecraft navigators a full list of all possible routes from a designated orbit, and the one that best fits the mission can be chosen. They can then choose the one that best suits their mission.

The researchers tested their technique on various planetary systems, including the Moon, and the Galilean moons of Jupiter.

“Spurred on by NASA’s Artemis program, the new Moon race is inspiring mission designers around the world to research fuel-efficient routes that can better and more efficiently explore the vicinity of the Moon,” said Baresi. “Not only does our technique make that cumbersome task more straightforward, but it can also be applied to other planetary systems, such as the icy moons of Saturn and Jupiter.”

The post How Knot Theory Can Help Spacecraft Can Change Orbits Without Using Fuel appeared first on Universe Today.

The list of chemicals found in space is growing longer and longer. Astronomers have found amino acids and other building blocks of life on comets, asteroids, and even floating freely in space. Now, researchers have found another complex chemical to add to the list.

The new chemical is known as 2-methoxyethanol (CH3OCH2CH2OH). It’s one of several methoxy molecules that scientists have found in space. But with 13 atoms, it’s one of the largest and most complex ones ever detected.

A team of scientists called the McGuire Group specializes in detecting chemicals in space. The McGuire Group and other researchers from institutions in Florida and France worked together to find 2-methoxyethanol.

The researchers published their findings in The Astrophysical Journal Letters. It’s titled “Rotational Spectrum and First Interstellar Detection of 2-methoxyethanol Using ALMA Observations of NGC 6334I.” The lead author is Zachary Fried, a graduate student in the McGuire Group at MIT.

A ball and stick model of 2-methoxyethanol (CH3OCH2CH2OH). With 13 atoms, it’s one of the largest complex chemicals ever found in space. Image Credit: By Ben Mills – Own work, Public Domain, https://commons.wikimedia.org/w/index.php?curid=3081683

“There are a number of ‘methoxy’ molecules in space, like dimethyl ether, methoxymethanol, ethyl methyl ether, and methyl formate, but 2-methoxyethanol would be the largest and most complex ever seen,” said lead author Fried.

The researchers didn’t stumble upon the large molecule. It was found as part of a concerted effort to detect new chemicals in space. It all started with machine learning. In 2023, one machine-learning model suggested they look for 2-methoxyethanol. The next step was the lab, where researchers performed experiments that measured and analyzed the molecule’s rotational spectrum here on Earth.

“We do this by looking at the rotational spectra of molecules, the unique patterns of light they give off as they tumble end-over-end in space,” said Fried. “These patterns are fingerprints (barcodes) for molecules. To detect new molecules in space, we first must have an idea of what molecule we want to look for, then we can record its spectrum in the lab here on Earth, and then finally we look for that spectrum in space using telescopes.”

The researchers measured the molecule’s spectrum over a broadband region of frequencies ranging from the microwave to sub-millimetre wave regimes (from about 8 to 500 gigahertz).

With that data in hand, the researchers turned to ALMA, the Atacama Large Millimetre/sub-millimetre Array. ALMA gathered data from two star-forming regions: NGC 6334I and IRAS 16293-2422B. Researchers from the McGuire Group, the National Radio Astronomy Observatory, and the University of Copenhagen all worked on analyzing ALMA’s observations.

“Ultimately, we observed 25 rotational lines of 2-methoxyethanol that lined up with the molecular signal observed toward NGC 6334I (the barcode matched!), thus resulting in a secure detection of 2-methoxyethanol in this source,” said Fried. “This allowed us to then derive physical parameters of the molecule toward NGC 6334I, such as its abundance and excitation temperature. It also enabled an investigation of the possible chemical formation pathways from known interstellar precursors.”

NGC 6334m the Cat’s Paw Nebula. Image Credit: ESO

Here on Earth, 2-methoxyethanol is used mostly as a solvent. It’s toxic to bone marrow and testicles. But its status here on Earth isn’t relevant to its discovery.

The large molecule isn’t a building block for life, either. It’s significant because of its size and complexity. Scientists are interested in understanding how chemistry evolves and forms large molecules in regions where stars and planets are forming.

“Our group tries to understand what molecules are present in regions of space where stars and solar systems will eventually take shape,” explained Fried. “This allows us to piece together how chemistry evolves alongside the process of star and planet formation.”

Molecular complexity is the hallmark of life, so, of course, scientists want to understand molecular complexity in space. As of 2021, scientists only found six molecules in space larger than 13 atoms outside our Solar System. McGuire’s team found many of them.

Finding them is the first step. The next step is to figure out how and where they form. Though there are no direct links between 2-methoxyethanol and life, all complex chemistry has something to tell us about complex chemistry in general.

“Continued observations of large molecules and subsequent derivations of their abundances allows us to advance our knowledge of how efficiently large molecules can form and by which specific reactions they may be produced,” said Fried. “Additionally, since we detected this molecule in NGC 6334I but not in IRAS 16293-2422B, we were presented with a unique opportunity to look into how the differing physical conditions of these two sources may be affecting the chemistry that can occur.”

IRAS 16293?2422 in the star-forming region Rho Ophiuchi. Image Credit: ESO

NGC 6334I is a higher-mass star-forming region compared to IRAS 16293-2422B. That means it could have a potentially enhanced radiation field. That enhanced radiation could produce more precursors for 2-methoxyethanol, eventually leading to more of the molecule itself. Warmer dust temperatures may have contributed, too. Warmer dust allows greater dust mobility, leading to chemical fragments being allowed to recombine.

Thanks to ever-improving observational tools and methods, including machine learning, astrochemistry is a blossoming field. If we’re ever going to understand how life on Earth arose and where it may likely rise elsewhere in the galaxy, astrochemistry will play a leading role. Though 2-methoxyethanol isn’t directly related to life, its detection still tells scientists something.

The post Another New Molecule Discovered Forming in Space appeared first on Universe Today.

Just watch this space and I’ll provide updates as I get them. Here’s a report from the Chicago Maroon, which also has an update page.

April 29, 2024, 12:40 p.m.:

As a speaker from UChicago Jews for a Free Palestine spoke at the rally, a director and rabbi of Chabad attempted to walk through the encampment area before protestors stopped him. UCPD told protestors that they cannot block the path, and the rabbi proceeded to walk in front of the rally’s speaker. He stood behind the speakers as they spoke.

– Eva McCord, Co-Editor-in-Chief, Anu Vashist, Managing Editor, Katherine Weaver, Deputy News Editor

I’ll walk through the encampment in a while.

 

Astronomers have confirmed that differences in binary stars' composition can originate from chemical variations in the cloud of stellar material from which they formed. The results help explain why stars born from the same molecular cloud can possess different chemical composition and host different planetary systems, as well as pose challenges to current stellar and planet formation models.

Virtual reality dance made easier with crowd wave technique. Open source code can be downloaded for Quest 2 and 3.

Virtual reality dance made easier with crowd wave technique. Open source code can be downloaded for Quest 2 and 3.

Climate change means many tree species planted today in Europe won’t survive to the end of the century, but English oaks could thrive in many areas

This article by Erec Smith was first published in the Boston Globe, where you can find an archived link here, but has also been published unpaywalled by the Cato Institute, a libertarian think tank where author Erec Smith is a research fellow (he’s also “an associate professor of rhetoric and composition at York College of Pennsylvania, and cofounder of Free Black Thought”).

Smith’s thesis is that DEI is racist because it rests on prescribing “approved ways” that black people should behave and think, ways that he instantiates by giving two quotes. The first is a now-deleted tweet by Nikole Hannah-Jones:

And from President Biden:

“If you have a problem figuring out whether you’re for me or Trump, you ain’t Black.”

That, says Smith, is “a statement that implicitly prescribes how Black voters should think.”

Smith developed this take because as a black kid in a white school he was expected to “act black,” yet when he moved to a mostly black school he was criticized for “acting white”—speaking “white English” and so on.  DEI, he avers, practices “prescriptive racism” by expecting black people to have the opinions that other “progressive” black people have, so that there is an approved and proper way of Thinking While Black promoted by DEI. Smith also criticizes right-wing racists for their past practice of criticizing “uppity Negroes” who didn’t act like black people should, though we don’t see much of that these days.

When Smith got to college and then became a faculty member, he saw this same tendency in DEI, except that the “uppity Negroes” are now those blacks who don’t conform to the prescribed progressive ideology. You can think of some “uppity” blacks, including people like John McWhorter, Glenn Loury, Coleman Hughes, and Thomas Sowell, all worth reading or listening to.

Click to read:

I’ll give a few excerpts:

Unlike traditional racism — the belief that particular races are, in some way, inherently inferior to others — prescriptive racism dictates how a person should behave. That is, an identity type is prescribed to a group of people, and any individual who skirts that prescription is deemed inauthentic or even defective. President Biden displayed prescriptive racism when he said “If you have a problem figuring out whether you’re for me or Trump, you ain’t Black,” a statement that implicitly prescribes how Black voters should think.

. . .prescriptive racism casts a broader net, disadvantaging people for not abiding by a long list of things a Black person shouldn’t do. A prescriptive racist may not mind that a Black person has a master’s degree, but he may scoff at the sight of a Black man watching the Masters — especially if Tiger isn’t playing. A white prescriptive racist would look at a Black person speaking standard English the way a Black person would look at a white person wearing a dashiki. Lest you think that last statement is mere speculation, I have met several people who have voiced derision and irritation upon hearing standard English come out of my mouth. My use of language was an affront to their expectations and sensibilities.

Many prescriptive racists are often people of the same minority group. A Black person lambasting another Black person for acting in ways deemed racially inauthentic — for example, speaking in dialects coded “white” — is engaging in prescriptive racism.

And how it enters DEI:

And prescriptive racism is not just a social phenomenon; it is now being institutionalized. More and more, it is erroneously labeled diversity, equity, and inclusion, and it is winning out over initiatives more in line with the civil rights movement and classical liberal values like individuality, free speech, reason, and even equality. It is becoming policy in academia, corporate America, and even the military. To put it another way, contemporary DEI is prescriptive racism.

In academia, I’ve found, Blackness is a role, a “pre‐​script,” to which Black people are expected to conform if they want to be accepted or, sometimes, acknowledged at all. A Black scholar cannot simply study and write about Plato; she has to write about Plato from a Black perspective. Nobody shows much interest in a Black graduate student drafting a dissertation on American Transcendentalism that isn’t focused on its relevance to the Black experience. In this sense, applying for graduate school or a professorship is akin to auditioning for “Black person” in some live‐​action role‐​playing event.

I hadn’t realized the expectations outlined in the second paragraph, but I’m sure they’re true, for nearly every black academic I know of is engaged in writing about the connection between their discipline and “blackness”. (This also applies to “studies” programs, in which white people also conform to DEI expectations by imbuing scholarship with ideology approved by DEI.)  What is clear is that DEI is racist in expecting groups to behave in certain approved ways and to hold certain approved views. John McWhorter, for instance, has not done that, and he’s suffered for it. As he says, he’ll never be invited to another linguistics meeting nor get an invitation to speak about linguistics at another university.  What a pity for such a smart guy! But that’s what you suffer for thinking independently—for being “heterodox.”

One more quote on “political blackness”:

Political Blackness made much more sense several decades ago. Both Malcolm X and the Rev. Martin Luther King Jr. could have been construed as politically Black. Why? Because, when these men lived, whether Black Americans were gay or straight, Islamic or Christian, working class or middle class, none of them could sit at the front of the bus in the Jim Crow South. However, in this third decade of the 21st century, the efficacy of political Blackness has waned significantly. Though things are not perfect and racist environments still exist, policy changes have afforded Black Americans opportunities and resources traditionally denied them. As a result, “the Black experience” has become so varied that the use of “the” is questionable.

The idea of an indefinite abject oppression that justifies essentialism and political Blackness does not reflect reality. The facts that roughly 80 percent of Black Americans are working class or higher and that the number of Black immigrants has skyrocketed (strongly suggesting that the United States isn’t a fundamentally anti‐​Black country) are just two of many things that illustrate this. But activists who still want power must fabricate an insidious specter of oppression, and an essential victimhood has to be prescribed, whether they are homeless or Oprah Winfrey. If you are a Black American who does not abide by this prescription, be you liberal or conservative, you are seen as weakening the political power of Black Americans.

The inherent paradox of contemporary social justice is the essentialism that says “you are bad if you stereotype other people, but you are also bad if you don’t.”

Smith goes on to say that he and others have founded a new organization to combat prescriptive racism:

I and a few others have cofounded Free Black Thought, a nonprofit newsletter and podcast representing “the rich diversity of Black thought beyond the narrow spectrum of views promoted by mainstream outlets as defining ‘the Black perspective.’” We come from a classical liberal standpoint, meaning we believe people should be treated as sovereign individuals and not deindividuated members of a group. In other words, we’re sticking it to the prescriptive racists.

The “free” in Free Black Thought is both an adjective and a verb. We want to promote thought free from the tyranny of prescription, which means we publish and promote a wide array of ideological points and artistic expression, highlighting Black artists and thinkers typically neglected in mainstream media. But we also seek “to free” Black thought by offering alternatives to K‑12 curricula informed by critical social justice, like BLM in Schools and Woke Kindergarten, to let schools know that other ways to promote true DEI do exist.

Another sin laid at the door of DEI, which I’m hoping is on the way out. Note that I said “hoping”, not “predicting.”

The JWST is flexing its muscles with its interferometry mode. Researchers used it to study a well-known extrasolar system called PDS 70. The goal? To test the interferometry mode and see how it performs when observing a complex target.

The mode uses the telescope’s NIRISS (Near Infrared Imager and Slitless Spectrograph) as an interferometer. It’s called Aperture Masking Interferometry (AMI) and it allows the JWST to reach its highest level of spatial resolution.

A team of astronomers used the JWST’s AMI to observe the PDS 70 system. PDS 70 is a young T-Tauri star about 5.4 million years old. At that young age, its protoplanetary disk still surrounds it. PDS 70 is a well-studied system that’s caught the attention of astronomers. It’s unique because its two planets, PDS 70 b and c, make it the only multiplanet protoplanetary disk system we know of.

The researchers wanted to determine how easily the AMI would find PDS 70’s two known planets and what else it could observe in the system.

Their research is “The James Webb Interferometer: Space-based interferometric detections of PDS 70 b and c at 4.8 µm.” It’s available on the pre-print site arxiv.org and hasn’t been peer-reviewed yet. The lead author is Dori Blakely from the Department of Physics and Astronomy at the University of Victoria, BC, Canada.

PDS 70 is known for its pair of planets. PDS 70 b is about 3.2 Jupiter masses and follows a 123-year orbital period. PDS 70 c is about 7.5 Jupiter masses and follows a 191-year orbit. One of the most puzzling things about the system is that PDS 70 b appears to have its own accretion disk. The system also shows intriguing evidence of a third body, maybe another star.

The JWST’s interferometry easily detected both planets. In fact, the observations found evidence of circumplanetary disk emissions around PDS 70 b and c. “Our photometry of both PDS 70 b and c provide evidence for circumplanetary disk emission,” the researchers write. That means we can see the star and its protoplanetary disk, where planets form, and the individual circumplanetary disks around each planet. Those disks are where moons form, and seeing them in a system 366 light-years away is very impressive.

The PDS 70 system as seen by the JWST’s interferometry mode and after extensive data processing. A yellow star marks the location of PDS 70, with PDS 70 b and c also shown. The JWST shows the infrared emissions coming from the disk. Image Credit: Blakely et al. 2024.

The JWST’s AMI observations also found a third point source. Its light is different from the light from the pair of planets and more similar to the light from the star. If it’s another planet, its composition is different from the others. If it’s not another planet, that doesn’t mean it necessarily has to be another star. The JWST could be seeing scattered starlight from another gaseous, dusty structure or clump in the disk. “This indicates that what we observe is not due to a simple inner disk structure, and may hint at a complex inner disk morphology such as a spiral or clumpy features,” the researchers explain.

The unexplained third source could be something more exotic. Previous research also identified the source and suggested that it could be an accretion stream flowing between PDS 70 b and c. “We interpret its signal in the direct vicinity of planet c as tracing the accretion stream feeding its circumplanetary disk,” the authors of the previous research wrote.

These images are from previous research that used the JWST but not its interferometry mode. The top row is from the telescope’s F187N filter, and the bottom row is from the telescope’s F480M filter. The left column shows the complete images. The middle column shows the system with the disk subtracted. The right column shows the system with the disk and both known planets extracted. What remains is a potential third planet, planet “d,” and an arm-like feature and potential accretion stream. Image Credit: V. Christiaens et al. 2024.

Or, perhaps most exciting, the source could be another planet. “Another scenario is that the signal we observe is due to an additional planet interior to the orbit of PDS 70 b,” the authors explain. “Follow-up observations will be needed to determine the nature of this emission,” the authors write.

Part of the observations’ success comes from what it didn’t detect. Protoplanetary disks are dusty and difficult to examine. The JWST has a leg up on it because it can see infrared light. When used in interferometry mode, it’s a powerful tool. The fact that it failed to detect any other planets is progress, though. “Additionally, we place the deepest constraints on additional planets,” in part of the disk. These constraints will help future researchers examine the PDS 70 system and other extrasolar systems.

The results also show another of AMI’s strengths: its ability to see into parts of the parameter space that other telescopes can’t. “Furthermore, our results show that NIRISS/AMI can reliably measure relative astrometry and contrasts of young planets in a part of parameter space (small separations and moderate to high contrasts) that is unique to this observing mode, and inaccessible to all other present facilities at 4.8 µm,” the authors explain.

The JWST has already established its place in the history of astronomy. It’s delivered on its promise and has already significantly contributed to our understanding of the cosmos. The telescope’s observations with its Aperture Masking Interferometry mode will further cement its place in history.

“Here, using the power of the James Webb Interferometer, we detect PDS 70, its outer disk, and its two protoplanets, b and c. These are the first planets detected with space-based interferometry,” the authors write.

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