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How Rembrandt combined special pigments for golden details of The Night Watch

Matter and energy from Science Daily Feed - Wed, 07/24/2024 - 9:30am
Chemists have for the first time established how Rembrandt applied special arsenic sulfide pigments to create a 'golden' paint.
Categories: Science

A single-molecule-based organic porous material with great potential for efficient ammonia storage

Matter and energy from Science Daily Feed - Wed, 07/24/2024 - 9:30am
Novel porous crystalline solid shows promise as an efficient and durable material for ammonia (NH3) capture and storage, report scientists. Made through a simple reprecipitation process, the proposed organic compound can reversibly adsorb and release NH3 via simple pressurization and decompression at room temperature. Its stability and cost-effectiveness make this material a promising energy carrier for future hydrogen economies.
Categories: Science

Images of nearest 'super-Jupiter' open a new window to exoplanet research

Space and time from Science Daily Feed - Wed, 07/24/2024 - 9:30am
Using the James Webb Space Telescope (JWST), astronomers imaged a new exoplanet that orbits a star in the nearby triple system Epsilon Indi. The planet is a cold super-Jupiter exhibiting a temperature of around 0 degrees Celsius and a wide orbit comparable to that of Neptune around the Sun. This measurement was only possible thanks to JWST's unprecedented imaging capabilities in the thermal infrared. It exemplifies the potential of finding many more such planets similar to Jupiter in mass, temperature, and orbit. Studying them will improve our knowledge of how gas giants form and evolve in time.
Categories: Science

Jurassic fossils show modern mammals grow faster than ancient ones

New Scientist Feed - Wed, 07/24/2024 - 9:00am
The 166-million-year-old fossils of an adult and a juvenile of the same extinct mammal species reveal that they had longer "childhoods" and lifespans than similar species today
Categories: Science

Trees have an extra climate benefit thanks to methane-eating microbes

New Scientist Feed - Wed, 07/24/2024 - 9:00am
Methane, a potent greenhouse gas, is converted to CO2 by microbes in tree bark, meaning trees are even better for the climate than we thought
Categories: Science

How fast do we get out of shape and is there a way to slow the loss?

New Scientist Feed - Wed, 07/24/2024 - 8:00am
When we take a break from exercise, it can feel like we quickly go back to square one. But this isn't the case, and there are various ways to minimise the decline
Categories: Science

Jesus ‘n’ Mo ‘n’ Trump

Why Evolution is True Feed - Wed, 07/24/2024 - 7:45am

Today’s Jesus and Mo strip, called “Trump“, came with a short summary: “God wants you to stop projecting your own desires onto him.”

Clearly Mo is a Democrat!  But of course, anybody who wishes that Trump had been killed is morally off the rails, though I’ve heard that from a few people.

Categories: Science

We may finally know how the placebo effect relieves pain

New Scientist Feed - Wed, 07/24/2024 - 7:33am
A brain circuit discovered in mice could explain why placebo treatments ease pain in people
Categories: Science

How to use psychology to hack your mind and fall in love with exercise

New Scientist Feed - Wed, 07/24/2024 - 6:00am
If the idea of exercise is more attractive than the reality, you aren't alone. But there are ways to train your motivation and develop better habits
Categories: Science

Moon bases will need to be 3 metres underground to avoid radiation

New Scientist Feed - Wed, 07/24/2024 - 5:37am
To keep long-term moon residents safe from harmful radiation, lunar bases will need to be built several metres under the surface or inside caves or lava tubes
Categories: Science

AI can predict tipping points for systems from forests to power grids

New Scientist Feed - Wed, 07/24/2024 - 5:00am
Combining two neural networks has helped researchers predict potentially disastrous collapses in complex systems, such as financial crashes or power blackouts
Categories: Science

The Evidence for Rehabilitation Robots

Science-based Medicine Feed - Wed, 07/24/2024 - 4:58am

Rehabilitation robots, first introduced in the 1990s, are just what they sound like – robotics used to aid in regaining function through rehabilitation following an injury. The idea sounds compelling, and the technology has been advancing steadily. But still we have to ask ourselves the question – do they actually help, and what is the evidence? A recent comprehensive meta-analysis and systematic […]

The post The Evidence for Rehabilitation Robots first appeared on Science-Based Medicine.
Categories: Science

Komodo dragons have teeth capped with a layer of iron

New Scientist Feed - Wed, 07/24/2024 - 4:55am
An orange layer on the tips of Komodo dragons’ teeth may give the enamel extra strength for ripping apart their prey
Categories: Science

Collision between boat and basking shark captured by camera tag

New Scientist Feed - Wed, 07/24/2024 - 1:00am
Researchers are calling for greater protection for basking sharks after a camera on a tagged shark recorded a collision for the first time
Categories: Science

Neanderthal cooking skills put to the test with birds and stone tools

New Scientist Feed - Tue, 07/23/2024 - 10:00pm
In an effort to understand ancient Neanderthal food preparation techniques, researchers butchered five wild birds using flint stone tools and roasted them
Categories: Science

Large language models don't behave like people, even though we may expect them to

Computers and Math from Science Daily Feed - Tue, 07/23/2024 - 5:47pm
People generalize to form beliefs about a large language model's performance based on what they've seen from past interactions. When an LLM is misaligned with a person's beliefs, even an extremely capable model may fail unexpectedly when deployed in a real-world situation.
Categories: Science

Researchers leveraging AI to train (robotic) dogs to respond to their masters

Computers and Math from Science Daily Feed - Tue, 07/23/2024 - 5:47pm
An international collaboration seeks to innovate the future of how a mechanical man's best friend interacts with its owner, using a combination of AI and edge computing called edge intelligence. The overarching project goal is to make the dog come 'alive' by adapting wearable-based sensing devices that can detect physiological and emotional stimuli inherent to one's personality and traits, such as introversions, or transient states, including pain and comfort levels.
Categories: Science

A new way to make element 116 opens the door to heavier atoms

Matter and energy from Science Daily Feed - Tue, 07/23/2024 - 5:47pm
Researchers have successfully made super-heavy element 116 using a beam of titanium-50. That milestone sets the team up to attempt making the heaviest element yet: 120.
Categories: Science

New Horizons Measures the Background Light of the Universe

Universe Today Feed - Tue, 07/23/2024 - 5:25pm

Think about background radiation and most people immediately think of the cosmic background radiation and stories of pigeon excrement during its discovery. That’s for another day though. Turns out that the universe has several background radiations, such as infrared and even gravitational wave backgrounds. NASA’s New Horizons is far enough out of the Solar System now that it’s in the perfect place to measure the cosmic optical background (COB). Most of this light comes from the stars in galaxies, but astronomers have always wondered if there are other sources of light filling our night sky. New Horizons has an answer. No!

Ok lets talk pigeon excrement.  Back in 1965 two telecommunication engineers were exploring signal interference at the Bell Laboratory. Penzias and Wilson detected a faint ‘hum’ in all directions and initially put it down to pigeon excrement as they nested in the horn of the radio receiver. Instead, what they had discovered was the cosmic background radiation, the faint glow that permeates the entire universe and is the thermal radiation left over from the Big Bang. Studying it allows us to understand more about the Universe when it was 380,000 years old. 

The full-sky image of the temperature fluctuations (shown as color differences) in the cosmic microwave background, made from nine years of WMAP observations. These are the seeds of galaxies, from a time when the universe was under 400,000 years old. Credit: NASA/WMAP

In the late 80’s a different type of background radiation was detected; the infrared background radiation. It consists of the diffuse infrared glow that fills the universe coming from numerous sources throughout the history of the universe. It is mostly from thermal emissions from dust grains heated by stellar radiation. In addition to this is the gravity wave background although this has yet to be detected. 

Another hotly debated background is the cosmic optical background (COB), a diffuse light which originates from stars and galaxies and spans the whole of the visible spectrum. There has been gathering momentum in its study however with observations from Hubble Space Telescope and the Spitzer Infrared Telescope. The studies however revealed that a large contribution to a general background optical glow come from faint unresolved galaxies. The study of the COB allows us to explore the total energy output of the universe, about galaxy and star formation across the history of the cosmos. 

The detection of the COB is a challenging one however with Earth based instruments or even those in Earth orbit plagued by interference. The zodiacal light for example is the result of sunlight scattered by interplanetary dust, it is dominant in the inner solar system  and makes studies of the COB difficult. The New Horizon probe is ideally positioned out beyond the orbit of Pluto over 8 billion kilometres away from interference. On board New Horizons is the LORRI (Long Range Reconnaissance Imager) camera which was identified as an ideal platform to begin a search. 

The New Horizons instrument payload that is currently doing planetary science, heliospheric measurements, and astrophysical observations. Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute

Using images from the LORRI camera, a team of astronomers led by Marc Postman from the Space Telescope Science Institute attempted to measure the COB over the range 0.4 to 0.9 micrometers. The images were from high galactic latitudes to ensure no diffuse light from the Milky Way or scattered light from bright stars. Isolating the COB contribution to the total sky brightness levels required digitally subtracting the scattered light from bright stars and galaxies and from faint stars within the field that were fainter than that detectable by LORRI. Interestingly, the results showed that, based on the estimated galaxy counts in the sampled regions the COB is the result of light from all the galaxies within our observable region of the universe.

Source : New Synoptic Observations of the Cosmic Optical Background with New Horizons

The post New Horizons Measures the Background Light of the Universe appeared first on Universe Today.

Categories: Science

Next Generation Event Horizon Telescope To Unlock Mysteries of Black Holes

Universe Today Feed - Tue, 07/23/2024 - 4:16pm

The prospect of actually resolving the event horizon of black holes feels like the stuff of science fiction yet it is a reality. Already the Event Horizon Telescope (EHT) has resolved the horizon of the black holes at the centre of the Milky Way and M87. A team of astronomers are now looking to the next generation of the EHT which will work at multiple frequencies with more telescopes than EHT. A new paper suggests it may even be possible to capture the ring where light goes into orbit around the black hole at the centre of the Milky Way. 

Black holes are strange objects that are the powerhouses of many galactic phenomenon. They have a complex anatomy with a singularity at the centre, a point of infinite density where gravity is so intense that the laws of physics cease to work. Surrounding the singularity is the event horizon, the boundary beyond which, nothing, not even light can escape. Just outside the event horizon is the photon ring and it is here that light is bent into a circular orbit around the singularity. Further out than this is the accretion disk but the focus of the next generation Event Horizon Telescope will be the photon ring. 

The Event Horizon Telescope name is a little misleading for it is not one telescope but a global network of radio telescopes that work together to act as a virtual Earth-sized radio telescope. The technology that makes this happen is known as interferometry where the telescopes are all connected together. The very long baseline of the telescope or put more simply the fact it is virtually VERY big means it has incredible resolution capabilities allowing it to capture the event horizon around Sagittarius A at the centre of the Milky Way and also of the black hole at centre of M87.

The ALMA array in Chile. Once ALMA was added to the Event Horizon Telescope, it increased the EHT’s power by a factor of 10. Image: ALMA (ESO/NAOJ/NRAO), O. Dessibourg

The EHT was launched in 2009 but now attention is turning to the next generation. The addition of ten new dishes and a whole host of new technology will transform EHT. Modern high-speed data transfer protocols will speed up transfer times and the addition of new dishes and technology will mean EHT will be able to observe at 86, 230 and 345 GHz simultaneously. This allows for the utilisation of frequency phase transfer techniques where lower frequency data can be used to supplement higher frequency. Using this will mean integration times of minutes at 345 GHz rather than seconds opening up a whole universe of new observations such as, the photon rings of black holes. 

Studies of the supermassive black hole at the centre of M87 and Sagittarius A suggest a magnetically arrested accretion disk. In this accretion model, the accretion disk forms a series of irregular spiral streams and a vertical magnetic field, which is split into separate field lines, pokes through the accretion plane. As the disk rotates the material spirals inward, dragging the field lines and twist them around the axis of rotation leading to the formation of jets. These magnetically arrested disks exhibit symmetrically polarised synchrotron emissions which were used by a team of astronomers to study the detectability of the photon ring using next generation EHT.

M87 and the jet streaming away from its central supermassive black hole. Credits: NASA, ESA and the Hubble Heritage Team (STScI/AURA); Acknowledgment: P. Cote (Herzberg Institute of Astrophysics) and E. Baltz (Stanford University)

The paper authored by Kaitlyn M. Shavelle and Daniel C. M. Palumbo from the Princeton University and Harvard & Smithsonian (respectively) show through simulations that the planned enhancements to the EHT are likely to enable the detection of photon rings. In the analyses of the enhancements they find that the higher sensitivity of the new EHT will likely be more critical than better processing techniques in the detection of the photon ring.

Source : Prospects for the Detection of the Sgr A* Photon Ring with next-generation Event Horizon Telescope Polarimetry

The post Next Generation Event Horizon Telescope To Unlock Mysteries of Black Holes appeared first on Universe Today.

Categories: Science

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