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Satellite images reveal that when conditions are right, the pollution from industrial hotspots can cause snow to fall downwind and punch holes in clouds

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In this special solo episode, Michael Shermer reflects on the 2024 election.

In March 2021, astronomers observed a high-energy burst of light from a distant galaxy. Assigned the name AT 2021hdr, it was thought to be a supernova. However, there were enough interesting features that flagged as potentially interesting by the Automatic Learning for the Rapid Classification of Events (ALeRCE). In 2022, another outburst was observed, and over time the Zwicky Transient Facility (ZTF) found a pattern of outbursts every 60–90 days. It clearly wasn’t a supernova, but it was unclear on what it could be until a recent study solved the mystery.

One idea was that AT 2021hdr was a tidal disruption event (TDE),] where a star strays too close to a black hole and is ripped apart. This can create periodic bursts as the stellar remnant orbits the black hole, but TDEs don’t tend to have such regular patterns. So the team considered another model, where a massive interstellar cloud passes into the realm of a pair of binary black holes.

Simulations show how binary black holes interact with a gas cloud. Credit: F. Goicovic et al. 2016

Computer simulations show that rather than simply ripping apart the cloud, a binary black hole would churn the cloud as it consumes it. This would produce a periodic burst of light as the black holes orbit. The team observed AT 2021hdr using the Neil Gehrels Swift Observatory and found periodic oscillations of ultraviolet and X-ray light that match the transient bursts observed by ZTF. These observations match the simulations of a binary black hole.

Based on the data, the black holes have a combined mass of about 40 million Suns, and they orbit each other every 130 days. If they continue along their paths, the two black holes will merge in about 70,000 years. Without the passing cloud, we would have never noticed them.

The team plans to continue their observations of the system to further refine their model. They also plan to study how the black holes interact with their home galaxy.

Reference: L. Hernández-García, et al. “AT 2021hdr: A candidate tidal disruption of a gas cloud by a binary super massive black hole system.” Astronomy & Astrophysics 691 (2024)

The post Two Supermassive Black Holes on the Verge of a Merger appeared first on Universe Today.

Researchers have found that under certain conditions, a laser beam can act like an opaque object and cast a shadow, opening new possibilities for technologies that could use a laser beam to control another laser beam.

Researchers look to deep learning techniques in order to streamline the time-consuming process of identifying 2D materials.

Researchers look to deep learning techniques in order to streamline the time-consuming process of identifying 2D materials.

Researchers have developed robotic trousers that enable people to walk more easily while expending measurably less energy. The aim is to keep frail individuals and in particular the elderly mobile and healthy for longer.

How long did it take our Sun to form in its stellar nursery? Scientists are now closer to an answer. They succeeded in the measurement of the bound-state beta decay of fully-ionized thallium ions at the Experimental Storage Ring (ESR) of GSI/FAIR. This measurement has profound effects on the production of radioactive lead in asymptotic giant branch (AGB) stars and can be used to help determine the Sun's formation time.

How long did it take our Sun to form in its stellar nursery? Scientists are now closer to an answer. They succeeded in the measurement of the bound-state beta decay of fully-ionized thallium ions at the Experimental Storage Ring (ESR) of GSI/FAIR. This measurement has profound effects on the production of radioactive lead in asymptotic giant branch (AGB) stars and can be used to help determine the Sun's formation time.

Underwater robots that can predict waves in real-time could reduce the cost of producing offshore renewable energy, a study suggests.

By probing chemical processes observed in the Earth's hot mantle, scientists have started developing a library of basalt-based spectral signatures that not only will help reveal the composition of planets outside of our solar system but could demonstrate evidence of water on those exoplanets.

For a wide variety of emerging quantum technologies, such as secure quantum communications and quantum computing, quantum entanglement is a prerequisite. Scientists have now demonstrated a particularly efficient way in which photons can be entangled with acoustic phonons. The researchers were able to demonstrate that this entanglement is resilient to external noise, the usual pitfall of any quantum technology to date.

Researchers are utilizing artificial intelligence to analyze the behavior of laboratory mice more efficiently and reduce the number of animals in experiments.

A 'deep learning' artificial intelligence model can identify pathology, or signs of disease, in images of animal and human tissue much faster, and often more accurately, than people. The development could dramatically speed up the pace of disease-related research. It also holds potential for improved medical diagnosis, such as detecting cancer from a biopsy image in a matter of minutes, a process that typically takes a human pathologist several hours.

Researchers have implemented polyphenylene-based anion exchange membranes poised to make hydrogen production more efficient and durable. The robust hydrophobic design enables effective ion transport while resisting chemical degradation.

'Cool' white lights -- such as those in modern car headlights -- endanger moths by causing them to fly erratically, new research shows.

Researchers have developed a three-dimensional mathematical model of prostate cancer. The model depicts various processes, including tumour growth, genetic evolution and tumour cell competition.

Researchers have explored how a particular chemical can selectively trap certain molecules in the cavities of its structure -- even though in normal conditions it has no such cavities. This innovative material with now-you-see-them-now-you-don't holes could lead to more efficient methods for separating and capturing chemicals right across industry.

Robots that can sense touch and perceive temperature differences? An unexpected material might just make this a reality. Researchers are developing soft and intelligent sensor materials based on ceramic particles.

When it comes to telescopes, bigger really is better. A larger telescope brings with it the ability to see fainter objects and also to be able to see more detail. Typically we have relied upon larger and larger single aperture telescopes in our attempts to distinguish exoplanets around other stars. Space telescopes have also been employed but all that may be about to change. A new paper suggests that multiple telescopes working together as interferometers are what’s needed. 

When telescopes were invented they were single aperture instruments. A new technique emerged in the late 1800’s to combine optics from multiple instruments. This achieved higher resolution than would ordinarily be achieved by the instruments operating on their own. The concept involves analysis of the interference pattern when the incoming light from all the individual optical elements is combined. This is used very successfully in radio astronomy for example at the aptly named Very Large Array. It is not just radio waves that are used, infra-red and even visible light interferometers have been developed saving significant costs and producing results that would otherwise not be achievable from a single instrument.

Image of radio telescopes at the Karl G. Jansky Very Large Array, located in Socorro, New Mexico. (Credit: National Radio Astronomy Observatory)

One area of astronomical research is the study of exoplanets. Observing alien worlds orbiting distant stars presents a number of challenges but the two key difficulties are that they lie at great distances and orbit bright stars. The planets are usually small and faint making them almost (but not quite) impossible to study directly due to the brightness and proximity to their star. Some understanding of their nature can be gleaned from using the transit method of study. This involves studying starlight as it passes through any atmosphere present to reveal its composition. 

Direct imaging and study is a little more challenging and requires high resolution and sometimes a way of blocking light from the nearby star. To achieve direct observations requires angular resolution of a few milliarcseconds or even less (the full Moon covers 1,860,000 milliarcseconds!) This depends largely on the planets size and distance from Earth and from its host star. To give some idea of context, to resolve a planet like Earth orbiting the Sun from a distance of just 10 light years requires an angular resolution of 0.1 milliarcseconds. The James Webb Space Telescope has a resolution of 70 milliarcseconds so even that will struggle. 

This artist’s impression depicts the exomoon candidate Kepler-1625b-i, the planet it is orbiting and the star in the centre of the star system. Kepler-1625b-i is the first exomoon candidate and, if confirmed, the first moon to be found outside the Solar System. Like many exoplanets, Kepler-1625b-i was discovered using the transit method. Exomoons are difficult to find because they are smaller than their companion planets, so their transit signal is weak, and their position in the system changes with each transit because of their orbit. This requires extensive modelling and data analysis.

A paper recently authored by Amit Kumar Jha from the University of Arizona and a team of astronomers explores this very possibility. They look at using interferometry techniques to achieve the required resolutions, at using advanced imaging techniques like the Quantum Binary Spatial Mode Demultiplexing to analyse the point spread function (familiar to amateur astronomical imagers) and at using quantum based detectors.

The study draws upon radio interferometric techniques with promising results. They showed that a multi-aperture interferometry approach utilising quantum based detectors are more effective than single aperture instruments. They will provide a super-resolution imaging solution that has to date not been used in exoplanetary research. Not only will it hugely increase resolution, it’s also a very cost effective way to observe exoplanets and indeed other objects across the cosmos. 

Source : Multi-aperture telescopes at the quantum limit of super-resolution imaging : Detecting subRayleigh object near a star

The post Interferometry Will Be the Key to Resolving Exoplanets appeared first on Universe Today.