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Engineers have demonstrated a system they've dubbed 'MadRadar' for fooling automotive radar sensors into believing almost anything is possible. The technology can hide the approach of an existing car, create a phantom car where none exists or even trick the radar into thinking a real car has quickly deviated from its actual course. And it can achieve this feat in the blink of an eye without having any prior knowledge about the specific settings of the victim's radar, making it the most troublesome threat to radar security to date.

Researchers describe the discovery of a new method that transforms everyday materials like glass into materials scientists can use to make quantum computers.

Researchers describe the discovery of a new method that transforms everyday materials like glass into materials scientists can use to make quantum computers.

The earliest galaxies are thought to have formed as the gravitational pull of dark matter, which has been impossible to study directly, slowly drew in enough hydrogen and helium to ignite stars. But astrophysicists now show that after the Big Bang, hydrogen and helium gas bounced at supersonic speeds off dense, slowly moving clumps of cold dark matter. When the gas fell back in millennia later, stars formed all at once, creating small, exceptionally bright galaxies. If models of cold dark matter are correct, the James Webb Space Telescope should be able to find patches of bright galaxies in the early universe, potentially offering the first effective test for theories about dark matter. If it doesn't, scientists have to go back to the drawing board with dark matter.

The field of exoplanet study continues to grow by leaps and bounds. As of the penning of this article, 5,572 extrasolar planets have been confirmed in 4,150 systems (with another 10,065 candidates awaiting confirmation. Well, buckle up because six more exoplanets have been confirmed around TOI-1136, a Sun-like star located roughly 276 light-years from Earth. This star is less than 700 million years old, making it relatively young compared to our own (4.6 billion years). This system will allow astronomers to observe how systems like our own have evolved with time.

The six-planet system was confirmed by the TESS Keck Survey, an international team of astronomers that searches for exoplanets by combing data obtained by the Transiting Exoplanet Survey Satellite (TESS) and the W.M. Keck Observatory (of which UC Riverside planetary astrophysics professor Stephen Kane is the principal investigator). The details of the six-planet system were presented in a series of papers that appeared in The Astronomical Journal. In the seventeenth and latest paper in the series, the survey team presented precise mass measurements of the six exoplanets, details about their orbits, and the characteristics of their atmospheres.

To date, most of the exoplanets observed by astronomers have been either individual discoveries or one of just a few planets. But in some cases, such as Kepler-90 and TRAPPIST-1, astronomers have observed many planets in a single system (8 and 7, respectively). Depending on the age of their parent star, these systems present astronomers with the opportunity to observe how multi-planet systems formed and evolved. In the case of TOI-1136, its age sets it apart from many known systems, being merely 700 million years old.

Artist’s impression of the planetary system around Kepler-90, a Sun-like star 2,545 light years from Earth. Credits: NASA

Tara Fetherolf, a visiting assistant professor of astrophysics at Cal State San Marcos and co-author of a new paper, explained in a UC Riverside News release:

“Because few star systems have as many planets as this one does, it’s getting close in size to our own Solar System. It’s both similar enough and different enough that we can learn a lot. This gives us a look at planets right after they’ve formed, and solar system formation is a hot topic. Any time we find a multi-planet system it gives us more information to inform our theories about how systems come to be and how our system.”

Initial observations of the system were made in 2019 using TESS, which was followed up with observations using the High-Resolution Echelle Spectrometer (HIRES) at the W.M. Keck Observatory and the Automated Planet Finder (APF) at the Lick Observatory. The latter observations allowed the team to precisely constrain the mass of the planets using the Radial Velocity measurements (where slight variations in the star’s motion indicate the gravitational forces acting on it). This yielded estimates of about 3.5 (TOI-1135 b) to 9.7 (TOI-1135 f) Earth masses, placing them between Super Earths to Mini-Neptunes.

The team also used Transit Timing variations, where dips in a star’s luminosity are used to determine the presence of planets (and their size). They then created computer models where the velocity measurements were layered over the transit data, yielding more information about the system. Typically, young stars are difficult to study because they are so active, possessing powerful magnetic fields, sunspots, and powerful solar flares that influence their planets by affecting their atmospheres. Since all the planets observed around TOI-1136 are of a similar age, they likely formed under similar conditions.

An amusing rendition of the TOI-1136 system if each body in the system were a duck or duckling. Credit: Rae Holcomb/UCI

And since the planets of this system are relatively close to each other, the team was able to measure something hard to gauge in other systems. As Kane summarized:

“Young stars misbehave all the time. They’re very active, just like toddlers. That can make high-precision measurements difficult. This will help us not only do a one-to-one comparison of how planets change with time but also how their atmospheres evolved at different distances from the star, which is perhaps the most key thing.”

The results of this study could have far-reaching implications for exoplanet research and the search for life in the cosmos (astrobiology). According to the most recent fossilized evidence, life emerged on Earth during the Archaean Eon (ca. 3.9 billion years ago), almost immediately after it formed. While many of TOI-1136’s planets orbit too closely and are subject to too much radiation to make life likely, the team hopes that observations of this system will ultimately answer questions of how our planet and life as we know it came to be.

“Are we rare?” said Kane. “I’m increasingly convinced our system is highly unusual in the Universe. Finding systems so unlike our own makes it increasingly clear how our Solar System fits into the broader context of formation around other stars.”

Further Reading: UC Riverside, The Astronomical Journal

The post Six Planets Found Orbiting an Extremely Young Star appeared first on Universe Today.

Executives from Meta, TikTok and X were questioned by US lawmakers about the safety of children who use their products – experts say the companies need to do more than just provide parental controls

Nine out of ten people in a trial of a CRISPR treatment for potentially life-threatening inflammatory reactions seem to have been cured

When a prominent star in the night sky suddenly dims, it generates a lot of interest. That’s what happened with the red supergiant star Betelgeuse between November 2019 and May 2020. Betelgeuse will eventually explode as a supernova. Was the dimming a signal that the explosion was imminent?

No, and new research helps explain why.

Headline writers couldn’t resist the supernova angle, even though that explanation was never very likely. Eventually, it became clear that ejected dust from the star caused the dimming. New research based on observations before, during, and after the Great Dimming Event (GDE) supports the idea that dust from the star itself caused Betelgeuse’s drop in brightness.

A research letter titled “Images of Betelgeuse with VLTI/MATISSE across the Great Dimming” presents the infrared observations of Betelgeuse. The observations capture the star before, during, and after the GDE. The lead author is Julien Drevon, from the Université Côte d’Azur, France, and the European Southern University.

“To better understand the dimming event, we used mid-infrared long-baseline spectro-interferometric measurements of Betelgeuse taken with the VLTI/MATISSE instrument before (Dec. 2018), during (Feb. 2020) and after (Dec. 2020) the GDE,” the research letter states. In particular, their observations focus on silicon monoxide (SiO.)

The authors of the new research outline three steps in the process that created the GDE.

Step One

The GDE started with shocks deep inside Betelgeuse. They generated a convective outflow of plasma that brought material to the star’s surface. Researchers detected a strong shock in February 2018 and a weaker one in January 2019. The second, weaker shock boosted the effect of the stronger shock that preceded it, generating a progressive plasma flow at the surface of Betelgeuse’s photosphere.

Step Two

The plasma flowing to the photosphere’s surface created a hot spot. Hubble UV observations of Betelgeuse revealed the presence of a luminous, hot, dense structure in the star’s southern hemisphere, between the photosphere and the chromosphere.

Step Three

Stellar material detaches from the photosphere and forms a gas cloud above Betelgeuse’s surface. A colder region forms under this cloud as a dark spot. Since it’s cooler, dust is allowed to condense above this region and in the part of the cloud above it. That dust is what blocked some of Betelgeuse’s luminosity, causing the GDE.

Previous research revealed this three-step process behind the GDE. The authors of the new research article set out to observe Betelgeuse’s close circumstellar environment to probe and monitor its geometry. In the wavelength range they worked in, SiO spectral features are prominent, and they’re used to understand what happened with the red supergiant. In astronomy, SiO is used as a tracer for shocked gas in stellar outflows since it persists at high temperatures.

This figure from the research letter shows some of the data the researchers worked with. The top panel shows the absolute spectra during each observed epoch. The bottom panel shows the relative flux for the SiO bands. The bands are deeper during the GDE than either before or after. Image Credit: J. Drevon et al. 2024.

In their article, the authors focus on the SiO (2-0) band and what it signifies. They note how the band’s intensity contrast increases by 14% during the GDE. “Therefore, it seems that during the GDE, we observe brighter structures in the line of sight,” they explain.

Next, they note a 50% decrease in intensity contrast in December 2020. What does it mean?

“The SiO (2–0) opacity depth map shows, therefore, strong temporal variations within 2 years, indicative of vigorous changes in the star’s environment in this time span,” they write.

Their observations also suggest “the presence of an infrared excess in the pseudo continuum during the GDE, which has been interpreted as new hot dust formed,” Drevon and his colleagues write.

This figure from the research article explains some of what the researchers found. The middle column is particularly interesting because it’s a reconstruction of the SiO (2-0) absorption band onto Betelgeuse’s surface for each of the three observed epochs. The third column is similar but shows the SiO (2-0) optical depth. Overall, they constrain the geometry of the dust feature that caused the GDE. Image Credit: J. Drevon et al. 2024.

It seems like the Great Dimming is no longer the mystery it once was. It also shows that Occam’s Razor is alive and well: “The explanation that requires the fewest assumptions is usually correct.”

The supernova proposal was fun for a while, and one day, Betelgeuse will explode as a supernova. But before it ever does, there are likely going to be several more episodes of dimming. For now, the authors say that the star is returning to normal.

“The Dec. 2020 observations suggest that Betelgeuse seems to be returning to a gas and surface environment similar to the one observed in Dec. 2018,” they write, “but with smoother structures, maybe
due to the unusual amount of dust recently formed during the GDE in the line of sight.”

Case closed?

The post Betelgeuse. Before, During and After the Great Dimming appeared first on Universe Today.

Although solar flares have been classified based on the amount of energy they emit at their peak, there has not been significant study into differentiating flares since slow-building flares were first discovered in the 1980s. Scientists have now shown that there is a significant amount of slower-type flares worthy of further investigation.

A new paper describes how, despite widespread enthusiasm about artificial intelligence's potential to revolutionize healthcare and the use of AI-powered tools on millions of patients already, no federal regulations require that AI-powered tools be evaluated for potential harm or benefit to patients.

A new system that brings together real-world sensing and virtual reality would make it easier for building maintenance personnel to identify and fix issues in commercial buildings that are in operation.

A new system that brings together real-world sensing and virtual reality would make it easier for building maintenance personnel to identify and fix issues in commercial buildings that are in operation.

Researchers have successfully developed a new time-resolved atomic force microscopy (AFM) technique, integrating AFM with a unique laser technology. This method enables the measurement of ultrafast photoexcitation phenomena in both conductors and insulators, observed through changes in the forces between the sample and the AFM probe tip after an extremely short time irradiation of laser light. This advancement promises substantial contributions to the creation of new scientific and technological principles and fields.

A joint research team has successfully induced polarization and polarity in metallic substances.

Carbon nanostructures could become easier to design and synthesize thanks to a machine learning method that predicts how they grow on metal surfaces. The new approach will make it easier to exploit the unique chemical versatility of carbon nanotechnology.

Carbon nanostructures could become easier to design and synthesize thanks to a machine learning method that predicts how they grow on metal surfaces. The new approach will make it easier to exploit the unique chemical versatility of carbon nanotechnology.

At low enough temperatures, certain metals lose their electrical resistance and they conduct electricity without loss. This effect of superconductivity is known for more than hundred years and is well understood for so-called conventional superconductors. More recent, however, are unconventional superconductors, for which it is unclear yet how they work.

At low enough temperatures, certain metals lose their electrical resistance and they conduct electricity without loss. This effect of superconductivity is known for more than hundred years and is well understood for so-called conventional superconductors. More recent, however, are unconventional superconductors, for which it is unclear yet how they work.

A team of researchers has achieved a major breakthrough in genome editing technology. They've developed a cutting-edge method that combines the power of designer-recombinases with programmable DNA-binding domains to create precise and adaptable genome editing tools.

A new patch uses tiny needles to measure electrical signals in the human body with incredible accuracy, even when these devices are stretched or twisted.