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US company Intuitive Machines is launching its Odysseus lander towards the moon's south pole. If all goes well, it will be the first private firm to put a spacecraft on the moon

New research establishes that the metric used to measure link prediction performance is missing crucial information, and link prediction tasks are performing significantly worse than popular literature indicates.

New research establishes that the metric used to measure link prediction performance is missing crucial information, and link prediction tasks are performing significantly worse than popular literature indicates.

A new 3D printing method uses ice to build a template for artificial blood vessels in engineered tissue. Researchers hope the vessels could eventually be used in artificial organ transplants or drug testing.

Fossils of a marine animal that lived 500 million years ago, combined with computer simulations, informed the design of a new soft robot.

Fossils of a marine animal that lived 500 million years ago, combined with computer simulations, informed the design of a new soft robot.

Scientists examined hundreds of birds in museum collections and discovered a suite of feather characteristics that all flying birds have in common. These 'rules' provide clues as to how the dinosaur ancestors of modern birds first evolved the ability to fly, and which dinosaurs were capable of flight.

A stone wall nearly a kilometre long found under the Baltic Sea may have been built by ancient hunters to channel deer into a confined space

Exposing mice to continuous loud noises changed the zinc levels in their inner ears, while a zinc-trapping compound helped prevent some of the damage

Scientists have discovered that a known practice in information technology can also be applied to chemistry. Researchers found that to enhance the sampling in chemical simulations, all you need to do is stop and restart.

A chemical element so visually striking that it was named for a goddess shows a 'Goldilocks' level of reactivity -- neither too much nor too little -- that makes it a strong candidate as a carbon scrubbing tool.

Engineers have studied how insects navigate, for the purpose of developing energy-efficient robots.

Engineers have studied how insects navigate, for the purpose of developing energy-efficient robots.

Children's interest in, and competence perceptions of, mathematics are generally quite positive as they begin school, but turn less positive during the first three years. This is shown by a recent study exploring the development of children's motivation for mathematics during the early school years, and how that development is associated with their mathematics competence. The researchers followed nearly three hundred children for three years.

Growing cartilage tissue in the lab could help patiens with injuries, but it is very hard to make the tissue grow in exactly the right shape. A new approach could solve this problem: Tiny spherical containers are created with a high-resolution 3D printer. These containers are then filled with cells and assembled into the desired shape. The cells from different containers connect, the container itself is degradable and eventually disappears.

A while back, 26 pro-Palestinian protestors at the University of Chicago, along with two faculty members, were arrested and booked for holding an illegal sit-in in the admissions office.  Later on, the city of Chicago dropped the charges of criminal trespass (I don’t know why this happened), and up to now I haven’t been able to find out if the miscreant students were receiving any discipline from the University.

Now, according to the Chicago Maroon (our student newspaper), it seems that the protestors have not even been slapped on the wrist, but only lightly tapped on the scaphoid. For it appears that the students were simply assigned by the University to write an essay on their sit-in experience. They were not required to show contrition or to promise they wouldn’t violate campus rules again. Instead, they were allowed to reiterate their support for Palestine and their accusation that the University engages in genocide. They also complained that their speech was being suppressed, which of course is not true. Their speech wasn’t suppressed; what was suppressed was performing that speech in a place where it obstructed campus access.

The student newspaper, which I now think is deeply biased towards the pro-Palestinian side (they have about ten pro-Palestinian articles and op-eds for every pro-Israel piece), produced not a news article about this, but rather a piece written by some of the protestors in UChicago United for Palestine (UCUP)—a consortium of like-minded groups that loves to violate university regulations and, most of the time, goes unpunished.

Read their “essays” by clicking on the link below. Remember, this story is not news, but a political screed disguised as news (it is labeled “letters” and “viewpoints”, but those labels often are used for very long political diatribes). For some reason the paper gives huge amounts of space to UCUP and the Students of Justice in Palestine to publish “letters” that can be over 4,000 words long. The only op-ed opposing their disruption was mine, and although the paper promised several months ago to put up a long pro-Israeli piece, for some reason it hasn’t appeared.  From the Nov. 28 issue:

Editor’s note: As The Maroon’s long-form and narrative features section, Grey City seeks to produce coverage that gives students a direct voice in reporting. As a separate report, Grey City will soon be publishing a story written by pro-Israel student organizer who has been active in recent campus demonstrations.

So far, bupkes.  I’d like to see the Maroon publish something beyond my letter showing that it is reporting objectively in this kerfuffle. They claim to be, but I don’t believe them.

Click to read.

 

Here’s part of the UCUP intro in which they whine about having their speech suppressed:

On November 9, 26 students and two faculty were arrested by the University of Chicago Police Department (UCPD) during a sit-in at Rosenwald Hall in protest of the University’s investments in institutions complicit in the genocide of Palestinians. Though legal charges have been dropped, the University’s disciplinary process is ongoing. Gathered here are excerpts from statements sent by student arrestees to Associate Dean of Students Jeremy Inabinet of the Center for Student Integrity, which we were required to submit in order to address charges brought against us by another associate dean of students through the University’s “disruptive conduct” disciplinary process. Administrators have repeatedly tried to push pro-Palestine narratives into the shadows, away from the public eye, including by weaponizing UCPD and the Dean-on-Call program against student protestors, processing our arrests inside a university building to avoid the large crowd outside, and subjecting us to an internal disciplinary process under the dean of students—the very university structure that filed the disciplinary complaint against us and that likely authorized our arrest.

. . . . We share the following letter excerpts to expose and condemn the University’s failure to protect our rights to free expression, as well as its bad faith promise to uphold “political neutrality” on our campus. Despite all of our efforts, the administration has never agreed to meet with us. Instead, President Alivisatos has since met publicly with the Israeli Consul General to strengthen ties to Israeli institutions in the middle of a genocide, while disciplining Palestinian students and their allies. In such a climate of blatant non-neutrality and suppression, we come forward openly and share our statements, which would otherwise be arbitrated behind closed doors.

The University has bent over backwards to protect their rights to free expression, and meeting with the Israeli Consul is not violating official University policy. These students are angry and entitled, and the university repeatedly lets them get away with violating the rules. (A recent illegal “lie in” in a campus restaurant went completely unpunished despite the presence of a Dean and three campus cops.)

A few excerpts from the “my sit-in experience” essays. Names are given where they’re reported, though some students wanted to remain anonymous, and of course I’ve preserved that anonymity.

“I am disturbed to have to write this letter to explain my presence at a peaceful, anti-genocide action that took place in Rosenwald Hall on November 9. The University’s response to this action reflects a highly securitized and carceral approach that actively chills student voices and directly contradicts its “commitment to free speech.”  (from an anonymous student)

***************

A coalition of Palestinian higher education institutions has issued a call for international academic institutions to:

1. Call for an immediate humanitarian ceasefire, guaranteed by the UN.
2. Urge immediate entry into Gaza of sufficient amounts of life-saving humanitarian needs (including water, food, fuel, medicine), equitably distributed throughout the whole territory of Gaza Strip.
3. Demand UN protection for the 2.3 million Palestinian civilians trapped under siege in Gaza.
4. Issue clear positions rejecting any ethnic cleansing.
5. To support in dismantling the settler colonial and apartheid system and to achieve a just, comprehensive, and lasting peace.

In response, major U.S. academic institutions like UChicago have silently continued to profit from the destruction of civilian infrastructure like universities and the slaughter of innocent Palestinians…”

Sammy Aiko Zimmerman, Class of 2024

***************

We have all heard numerous times that the University of Chicago has articulated principles on political neutrality in its Kalven Report, discouraging administrators from taking a stance on socio-political issues outside of the University in the name of preserving free expression. The University’s stance on institutional political neutrality, said to preserve the principle and practice of free inquiry and critique at the departmental, faculty, and student level is admirable at first sight. But the further I have inspected it and observed its consequences, the more it seems to mask a refusal to challenge status-quo power relations which are destroying free expression, and the possibility of education itself. How can UChicago administrators claim to uphold core values and principles of free expression by ignoring the student body’s calls for a meeting, mechanically citing the Kalven Report to the media, and passively watching Israel systematically target journalists, drop bombs on university buildings in the Gaza Strip, and brutally incarcerate our fellow students at Birzeit University without charge? Is the appropriate ethical attitude to wait until after the genocide is consummated and only then hold an intellectually challenging history seminar about it?…”

Hassan Doostdar, Class of 2025

****************

Seriously, in what way are these students having their right of free speech abrogated? They’re engaging in civil disobedience, which is fine, but that gives them no right to beef, as some have done, for getting arrested. And pardon me if I don’t think that accusations of campus complicity in genocide are the moral equivalent of the civil rights protestors of the Sixties.

The administration here seems to have decided to let protestors either get away with violating campus regulations or giving them only very light punishment. This, of course, is not deterrence, and I hope that Jewish parents aren’t themselves deterred from sending their kids here.

It was a $325 million dollar project that was intentionally smashed to smithereens in the interest of one day, saving humanity. The DART mission (Double Asteroid Redirection Test) launched in November 2021 on route to asteroid Dimorphos. Its mission was simple, to smash into Dimorphos to see if it may be possible to redirect it from its path. On impact, it created a trail of debris from micron to meter sized objects. A new paper analyses the debris field to predict where they might end up. 

Asteroid Dimorphos orbits around its host asteroid, Didymos and together they form a binary asteroid system. Neither asteroid poses a threat to Earth but their gave a fabulous opportunity to test technology for defending Earth from potential impactors. On 11 October NASA announced that DART successfully altered the orbit of Dimorphos showing that the kinetic energy of a spacecraft could indeed alter the trajectory of a potential threat. 

DART hit Dimorphos in an almost head on collision and the resulting ejecta plume travelled at approximately 2km/s. The plume had been observed by the Les Makes Observatory and with the Hubble Space Telescope. The debris contained material from dust sized particles to meteor and even boulder sized objects. Just before the impact, the CubeSat LICIACube was released from DART so that it could offer some long term monitoring of the debris field. 

Observations that followed showed delicate structures within the ejecta with a diffuse cloud that quickly transformed into a cone shaped formation with a tail. That tail, just like the tail of a comet was then pushed away from the asteroid system by the solar radiation pressure. Using ground based imagery, the mass and velocity of the ejected particles was established. 

The analysis of ejecta enabled modelling to be undertaken to estimate that approximately 3% of all ejected boulders would remain in orbit after 83 days (within the scope of the captured data). This estimation was in line with the pre-impact simulations over a 60 day period. By varying the parameters of the simulation they also revealed that 5% of 10cm sized particles escaping with a velocity of 0.12 and 0.18m/s would remain in orbit around the system after a 60 day period of time, similar again to the observations. 

Perhaps the greatest concern though is the long term fate of the larger boulder sized ejecta. Taking integrations covering 800 and 1550 days following the impact, the results showed a gradual decline in the number of boulders bound to the asteroid system. The good news is that for the most part, the reduction was due to collisions with Didymos and Dimorphos themselves. In no simulations was there any suggestion that any of the ejecta would escape the double asteroid system. 

What of the future, well to fully understand the results a follow up study is required. Hera is a European Space Agency mission slated to travel to Didymos and Dimorphos 5 years after the DART impact. On arrival it will assess the orbit of Dimorphos to understand its orbital changes. 

Source : On the fate of slow boulders ejected after DART impact on Dimorphos

The post What Happened to All Those Boulders Blasted into Space by DART? appeared first on Universe Today.

The hunger strike by pro-Palestinian students at Brown University—students aiming to get their school to divest from companies “associated with human rights abuses in Palestine”—didn’t work. It lasted just eight days, and then the students abandoned their fast unto death because their demands were deemed “obsolete”.  But now, it appears, the anti-Israel faction, likely to be students have adopted a new stratagem: issuing vile and violent threats against the campus Jewish organization of Hillel. This is of course part of the antisemitism fulminating on American college campuses.

Note: I’ve received an email from a Brown Vice-President, who, eager to protect his school’s reputation, admonished me that we don’t know if the hate emails originated from the campus. That’s indeed true, but I think that’s the most likely source, and I’m using Bayes’ Theorem here.

Here’s the letter that the President of Brown sent yesterday to the University community.

From: President Christina H. Paxson 
Date: Sun, Feb 11, 2024 at 9:49 PM
Subject: Threats to the Brown-RISD community

Dear Members of the Brown and RISD Communities,

We are writing to address the terrible threats against the Brown-RISD Hillel Weiner Center that our campuses were notified about this morning. Employees there received deeply disturbing antisemitic emails that included threats of violence against them personally and Brown-RISD Hillel.

Our primary concern is for the safety and security of members of the Brown and RISD communities, including the Brown-RISD Hillel community. Threats of violence against anyone on our campuses are completely unacceptable, and we are committed to working with law enforcement to do everything possible to help identify and prosecute the perpetrator(s).

This comes at an especially difficult time of distress on our campuses. Our students, faculty and staff continue to grapple with the deaths of Israelis, Palestinians and others in the wake of the October 7 attacks, as well as a despicable act of violence against a member of the Brown community here in the United States last November, and increases in reports of antisemitism, Islamophobia and other forms of hate targeting national origin and identity both nationally and on our campuses.

This is a time to reflect on who we are as educational communities that value human dignity and reject violence, racism, discrimination and intimidation. Our fervent hope is that, in this difficult time, each of us in the Brown and RISD communities renews our commitment to eschew all forms of hatred and work toward mutual understanding.

Our ongoing focus is making sure that members of our communities are protected and feel safe. As shared in campus safety alerts sent earlier today, the departments of public safety for both Brown and RISD continue to work with the Providence Police Department to investigate the source of the threats and ensure the ongoing safety and security of Brown-RISD Hillel. Part of their swift and immediate response was to reach out to federal, state and local law enforcement authorities, and to coordinate with the Rhode Island State Fusion Center, which gathers and shares information about threats between law enforcement agencies.

While we have been assured that, given the nature of the emailed threats, there is no evidence of ongoing concern for personal safety (and operations in the building can continue), robust security plans are in place to ensure the security of the building and the operations that take place there. Safety plans are also in place for the individuals who received the threats.

If at any time you learn about threats to yourself or others, please contact the Providence police, as well as public safety at your respective campus — NUMBER REDACTED for Brown community members and NUMBER REDACTED for RISD community members.

Sincerely,
Christina H. Paxson
President, Brown University

Crystal Williams
President, Rhode Island School of Design

I don’t see this as a violation of institutional neutrality so much as an attempt to quell disturbances and calm people on campus. And, as if to avoid taking a stand, Paxson and Williams include the obligatory denunciations of “Islamophobia” in their letter.  But one thing is certain: those who favor the Palestinian side of the conflict are far more hateful and violent than those favoring the Israeli side.

Note: The “despicable act of violence against a member of the Brown community here in the United States last November” refers to the shooting of three Palestinian college students who were walking in Vermont, an unconscionable act that left the Brown student, Hisham Awartani, paralyzed from the chest down. That’s a terrible fate and I wish him well. But as far as I know, there’s no evidence that this was an “Islamophobic” shooting, and the accused perp, 48-year-old Jason J. Eaton, remains in custody pending trial.

Now and then there is a bright radio flash somewhere in the sky. It can last anywhere from a few milliseconds to a few seconds. They appear somewhat at random, and we still aren’t sure what they are. We call them fast radio bursts (FRBs). Right now the leading theory is that they are caused by highly magnetic neutron stars known as magnetars. With observatories such as CHIME we are now able to see lots of them, which could give astronomers a new way to measure the rate of cosmic expansion.

The rate of cosmic expansion is described by the Hubble parameter, which we can measure to within a few percent. Unfortunately, our various methods of measure are now so precise their uncertainties don’t overlap. This contradiction in values is known as the Hubble tension. Several re-evaluations of our methods have ruled out systematic error, so astronomers look to new independent ways to measure the Hubble parameter, which is where a new study comes in.

The paper looks at using FRBs as a Hubble measure. For light from an FRB to reach us, it needs to travel millions of light-years through the diffuse intergalactic and interstellar medium. This causes the frequency of the light to spread out. The amount of spectral spreading is known as the Dispersion Measure (DM), and the greater the DM the greater the distance. So we know the distance to FRBs. But to measure cosmic expansion, we also need a second distance measure, and here the paper proposes using gravitational lensing.

The geometry of an FRB measurement. Credit: Tsai, et al

If the FRB light path passes relatively close to a massive object such as a star, the light can be gravitationally lensed around the object. From the width of the lensing, we have an idea of its relative distance to the FRB source. When the FRB light passes from the intergalactic medium to the more dense interstellar medium of our galaxy, there is a brightening effect known as scintillation, which gives us another distance measure A bit of geometry then allows us to calculate the Hubble parameter.

Based on their calculations, the authors estimate that a single lensed FRB observation would allow them to pin down the Hubble parameter to within 6% accuracy. With 30 or more events, they should be able to increase their precision to a fraction of a percent uncertainty. This would put it on par with other methods. This should be achievable given current and planned FRB telescopes.

New observation methods such as this are the only way we are going to resolve the Hubble tension. Hopefully, we will solve this mystery, and perhaps it will point us to a radically new understanding of cosmic evolution.

Reference: Tsai, Anna, et al. “Scintillated microlensing: measuring cosmic distances with fast radio bursts.” arXiv preprint arXiv:2308.10830 (2023).

The post Measuring Distances in the Universe With Fast Radio Bursts appeared first on Universe Today.

When black holes are born from collapsing stars, they emit a short-lived jet that may slow down the black hole’s rotation to nearly a standstill