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Wednesday: Hili dialogue

Why Evolution is True Feed - Wed, 08/14/2024 - 2:30am

Meanwhile, in Dobrzyn, Hili is suspicious:

Hili: This leaf looks like a small animal. A: But it is a withered leaf.

 

Hili: Ten liśc wygląda jak małe zwierzątko.
Ja: Ale to jest zeschnięty liść.
Categories: Science

Primordial Black Holes Could Kick Out Stars and Replace Them.

Universe Today Feed - Tue, 08/13/2024 - 5:37pm

Primordial black holes formed during the earliest stages of the evolution of the universe. Their immense gravity may be playing havoc in stellar systems. They can transfer energy into wide binary systems disrupting their orbits. Like celestial bullies their disruption might lead to extreme outcomes though like the ejection of a star, only to be replaced by the black hole itself! A new paper studies the interactions of systems like these and looks at ways we might be able to detect them. 

It’s been theorised that during the earliest moments after the Big Bang, black holes may have formed. They are not the result of supermassive stars having collapsed but instead have formed out of fluctuations in the density of matter. Regions with great density would simply collapse under their own gravitational influence forming what have been dubbed primordial black holes (PBHs). They are thought to vary in size from subatomic to some that are more massive than the Sun. 

Whether primordial black holes really do account for dark matter in the universe is still up for debate. Among the astronomical community it is generally accepted that they cannot account for all dark matter but probably account for up to 10% of dark matter in the planetary mass range (10-7 to 10-3 solar masses.) Whether this is PBHs account for any of the dark matter in the universe requires further analysis.

Researchers are making progress mapping dark matter, but they don’t know what it is. This is a 3D density map of dark matter in the local universe, with the Milky Way marked by an X. Dots are galaxies, and the arrows indicate the directions of motion derived from the reconstructed gravitational potential of dark matter. Image Credit: Hong et al., doi: 10.3847/1538-4357/abf040.

If large scale is taken into account then PBHs are indistinguishable from a background of particle dark matter. At small scales the distribution of PBHs is not uniform across the universe relative to the background of particle dark matter and so we are forced to look for a unique and new theory. Observing PBHs to understand how close the model is to reality is difficult but it is possible to study their interactions with star systems. 

In a paper published by Badal Bhalla from the University of Oklahoma and a team of astronomers they explore the way PBHs can lose energy when interacting with stellar binary systems. These interactions can result in any one of 5 possible outcomes; 

1: Hardening – the two bound objects lose energy to the third free object causing their separation to decrease;

2: Softening – the free body transfers energy to the bound system causing their separation to increase but remain bound;

3: Disruption – the free body transfers enough energy to the bound system that the components become unbound and all objects continue unbound;

4: Capture – the bound objects capture the free object;

5: Exchange – the free object transfers enough energy to unbind one of the bound objects and in doing so loses sufficient energy to become bound to the remaining one. 

Previous studies have explored softening and disruption in PBH and binary interactions as has the capture model. The team propose that hardening is also unlikely and so explore the possibility of the exchange model. They find that the exchange model should lead to a population of PBH binaries in the Milky Way and indeed some observations hint that they may exist. The team also suggest it may be possible to detect PBHs in binary systems with a sub-solar mass PBH by the properties of the system. Observations are now needed to validate the model. The discovery of black holes in a binary system may be detectable and go some way to support the findings.

Source : Dancing with invisible partners: Three-body exchanges with primordial black holes

The post Primordial Black Holes Could Kick Out Stars and Replace Them. appeared first on Universe Today.

Categories: Science

NASA’s Says Goodbye to its Asteroid-Hunting NEOWISE Mission

Universe Today Feed - Tue, 08/13/2024 - 4:34pm

NASA’s Wide-field Infrared Survey Explorer (WISE), launched in 2009, spent the next fourteen and half years studying the Universe in infrared wavelengths. During that time, it discovered thousands of minor planets, star clusters, and the first Brown Dwarf and Earth-Trojan asteroid. By 2013, the mission was reactivated by NASA as the Near-Earth Object Wide-field Infrared Survey Explorer (NEOWISE), which was tasked with searching for Potentially Hazardous Asteroids (PHAs). For ten years, the NEOWISE mission faithfully cataloged comets and asteroids that could pose a threat to Earth someday.

Unfortunately, NASA announced on July 1st that it would be decommissioning this planetary defense mission, which is expected to burn up in our atmosphere later this year. On Thursday, August 8th, the mission was decommissioned after the final command was sent from NASA’s Jet Propulsion Laboratory in Southern California and related to the spacecraft by the Tracking and Data Relay Satellite (TDRS) system. However, the scientific data NEOWISE collected during its ten years of operation will continue to inspire new discoveries!

The decision to end the mission was made because of an uptick in solar activity that’s been heating Earth’s upper atmosphere, causing it to expand and create drag on the spacecraft. This will cause NEOWISE to drop too low in its orbit to provide accurate scientific data, and NEOWISE does not have a propulsion system to maintain its orbit. Past and present mission members attended the decommissioning ceremony, which took place at the Earth Orbiting Missions Operation Center (EOMOC) at NASA JPL and the agency’s headquarters in Washington, D.C.

Animation of the many Near-Earth Objects (NEOs) that share Earth’s orbit. Credit: NASA.

The remaining scientific data was downlinked shortly after science operations officially ended on July 31st. Said Nicola Fox, associate administrator of NASA’s Science Mission Directorate at NASA HQ, in a recent NASA press release:

“The NEOWISE mission has been an extraordinary success story as it helped us better understand our place in the universe by tracking asteroids and comets that could be hazardous for us on Earth. While we are sad to see this brave mission come to an end, we are excited for the future scientific discoveries it has opened by setting the foundation for the next generation planetary defense telescope.”

During its nearly fifteen years of operations, the space telescope exceeded its scientific objectives (not once but twice) by remaining in operation far longer than expected. When it first launched as the WISE mission in 2009, the mission was intended to scan the infrared sky for seven months. By July 2010, the mission had accomplished this objective with far greater sensitivity than previous IR surveys and depleted its supply of solid hydrogen coolant a few months later. The mission was then extended until February 2011 under the name NEOWISE to complete its survey of the Main Asteroid Belt, at which point it was put into hibernation.

However, analysis of the WISE/NEOWISE data revealed that it could still operate without coolant and make precise observations of less faint objects like comets and asteroids that are heated by the Sun as they fly closer to our planet – in short, Near-Earth Objects (NEOs). By 2013, NASA recommissioned the space telescope under the Near-Earth Object Observations Program, which morphed into NASA’s Planetary Defense Coordination Office (PDCO) in 2016. Data processing for WISE and NEOWISE takes place at the Infrared Processing and Analysis Center at the California Institute of Technology (Caltech).

This illustration shows NASA’s NEO Surveyor against an infrared observation of a starfield made by the agency’s WISE mission. Credit: NASA/JPL-Caltech/University of Arizona

Said Amy Mainzer, the principal investigator of NEOWISE and NEO Surveyor at UCLA:

“After developing new techniques to find and characterize near-Earth objects hidden in vast quantities of its infrared survey data, NEOWISE has become key in helping us develop and operate NASA’s next-generation infrared space telescope. It is a precursor mission. NEO Surveyor will seek out the most difficult-to-find asteroids and comets that could cause significant damage to Earth if we don’t find them first.”

The NEOWISE mission conducted about 1.45 million infrared measurements of more than 44,000 solar system objects, which were used to create all-sky infrared maps. This included 215 of the more than 3,000 NEOs detected to date and 25 new comets. This included the long-period comet C/2020 F3 NEOWISE that appeared in the night sky during the summer of 2020 and was the brightest comet seen in the northern hemisphere since Comet Hale–Bopp streaked across the sky in 1997.

“The NEOWISE mission has been instrumental in our quest to map the skies and understand the near-Earth environment. Its huge number of discoveries have expanded our knowledge of asteroids and comets, while also boosting our nation’s planetary defense,” said Laurie Leshin, the director of NASA JPL. “As we bid farewell to NEOWISE, we also celebrate the team behind it for their impressive achievements.” 

In addition to leaving behind volumes of scientific data, WISE and NEOWISE helped pave the way for NASA’s next-generation infrared space telescope. This mission, the Near-Earth Object Surveyor (NEO Surveyor), will be the first purpose-built mission dedicated to monitoring potentially hazardous NEOs. Once operational, it will seek out some of the faintest NEOs, such as asteroids and comets with low albedos (meaning they don’t reflect much visible light) or those that approach Earth from the direction of the Sun. This telescope is currently under construction and will launch no earlier than 2027.

Further Reading: NASA

The post NASA’s Says Goodbye to its Asteroid-Hunting NEOWISE Mission appeared first on Universe Today.

Categories: Science

Is youth mental health really worse today than it was decades ago?

New Scientist Feed - Tue, 08/13/2024 - 4:30pm
Young people's mental health is declining, statistics suggest, but some have questioned whether this is just due to increased awareness of such conditions and reduced stigma around seeking help
Categories: Science

We keep finding water on Mars – here are all the places it might be

New Scientist Feed - Tue, 08/13/2024 - 2:44pm
Researchers recently found a possible reservoir of liquid water more than 11 kilometres below Mars's surface – the latest in a long series of potential water spottings on the Red Planet, hinting at its temperate past
Categories: Science

MDMA therapies hit a roadblock – what's next?

New Scientist Feed - Tue, 08/13/2024 - 2:30pm
The US Food and Drug Administration has rejected the psychedelic drug MDMA as a treatment for post-traumatic stress disorder, leading many to wonder whether psychedelic therapies have a future in medicine
Categories: Science

Mars Has Lots of Water, But It’s Out of Reach

Universe Today Feed - Tue, 08/13/2024 - 12:30pm

Mars was once wet, but now its surface is desiccated. Its meagre atmosphere contains only a tiny trace amount of water vapour. But new research says the planet contains ample liquid water. Unfortunately, it’s kilometres under the surface, well out of reach.

The question of what happened to Mars’ water is an enduring one. There’s ample evidence showing that water flowed across the planet’s surface, carving out river channels, creating sediment deltas, and filling lakes. It may even have had ocenas. The planet was likely warm and wet until around 3.8 billion years ago, during the transition from the Noachian Period to the Hesperian Period. Over time it lost both its thick atmosphere and its water.

The most widely accepted explanation for the water’s disappearance is that the planet’s magnetic shield weakened and that the solar wind blew most of the water away into space.

New research published in the Proceedings of the National Academy of Sciences (PNAS) presents a new wrinkle in the Mars water mystery. Its title is “Liquid water in the Martian mid-crust,” and the first author is Vashan Wright, an assistant professor at UC San Diego’s Scripps Institution of Oceanography.

“Understanding the Martian water cycle is critical for understanding the evolution of the climate, surface and interior,” Wright said in a press release. “A useful starting point is to identify where water is and how much is there.”

Wright and his colleagues worked with data from NASA’s InSight lander, which was sent to Mars to study the planet’s deep interior. InSight aimed to understand not only Mars but also the processes that shape all rocky planets. The mission ended in December 2022 when the lander became unresponsive, but scientists are still working with its data.

During its mission, InSight gathered seismic data with SEIS, the Seismic Experiment for Interior Structure. SEIS was sensitive to Marsquakes and meteorite impacts, and the seismic data is helping scientists understand Mars’ interior, including its core, mantle, and crust.

This image shows InSight’s SEIS, the Seismic Experiment for Interior Structure. It’s housed under a protective dome that shields it from wind and dust. Credit: NASA/JPL

“Large volumes of liquid water transiently existed on the surface of Mars more than 3 billion years ago,” the authors write in their published research. “Much of this water is hypothesized to have been sequestered in the subsurface or lost to space.”

Seismic waves sensed by SEIS can help determine if some of Mars’ water is in the planet’s subsurface. When seismic waves travel through a planet, they reveal information about the inner structure and composition. There are different types of waves, and some can’t travel through liquids. That’s how scientists learned that Earth has a liquid core.

Wave velocities and directions also reveal a lot. Velocity and direction change when the waves reach boundaries like the one between a planet’s crust and its mantle. Waves also provide information about the density and elasticity of materials they pass through. Changes in wave speed also reveal information about temperature differences.

But conclusions don’t jump out of data and announce themselves. Researchers have to work their way through the data and try to interpret it. The Mars science community is doing just that, and this research is the latest part of the effort.

Previous researchers have tried to constrain the conditions under the InSight Lander in Elysium Planitia. Scientists use the term upper crust to describe the depth down to about 8km and the term lower crust to describe the depth between 8 km and about 20 km. Some research from orbiters showed that the upper crust is like a cryosphere that contains abundant frozen water. Orbital images of recent meteorite impacts appear to show exposed ice.

But this new research goes against that. The authors write that seismic waves “in the upper 8 km beneath InSight is lower than expected for an ice-saturated cryosphere.”

Previous research also showed that the lower crust contains either highly porous mafic rock or less porous felsic rock. However, it was difficult to determine how much water was contained in the pores.

That’s where this research comes in.

“We assess whether Vs, Vp, and bulk density ?b data are consistent with liquid water-saturated pores in the mid-crust (11.5 ± 3.1 to 20 ± 5km) within 50 km of the InSight lander,” the authors write. Vs means the velocity of secondary seismic waves, Vp means the velocity of primary seismic waves, and pb means bulk density. The bulk density means the mass of a volume unit of rock including any liquid trapped in its pores.

According to the authors, the mid-crust is one of our identifiable layers under the InSight lander. It may even be global, but there is not enough data to conclude that yet.

However, the researchers did reach another conclusion: “A mid-crust composed of igneous rock with thin fractures filled with liquid water can best explain the geophysical data.”

If the InSight Lander location is representative of the rest of Mars, the approximately 11.5 km to 20 km deep mid-crust could hold an enormous amount of water. There could be enough to cover the entire planet in a layer of water 1 to 2 km deep. Of course, this is just a thought exercise since Mars’ wouldn’t be able to hold onto the surface water.

If the planet does hold such a vast amount of water, it won’t be of much use to human visitors trying to establish a presence there. Even on Earth, drilling only 1 km into the surface is difficult. It’s challenging to conceive of a way to drill 11 km deep on Mars.

But where there’s water, there could be life.

“Establishing that there is a big reservoir of liquid water provides some window into what the climate was like or could be like,” said co-author Michael Manga, a UC Berkeley professor of earth and planetary science. “And water is necessary for life as we know it. I don’t see why [the underground reservoir] is not a habitable environment.”

It may very well be habitable, but that doesn’t mean it’s inhabited. It is at least a possibility, though.

We’ve found life at a depth of 5 km within Earth’s crust. Could the same thing be possible on Mars?

Just like the water, an answer to that question is well out of reach. For now.

The post Mars Has Lots of Water, But It’s Out of Reach appeared first on Universe Today.

Categories: Science

SwRI-led team finds evidence of hydration on Asteroid Psyche

Space and time from Science Daily Feed - Tue, 08/13/2024 - 12:21pm
Using data from NASA's James Webb Space Telescope, astronomers have confirmed hydroxyl molecules on the surface of the metallic asteroid Psyche. The presence of hydrated minerals suggests a complex history for Psyche, important context for the NASA spacecraft en route to this interesting asteroid orbiting the Sun between Mars and Jupiter.
Categories: Science

Scientists achieve more than 98% efficiency removing nanoplastics from water

Matter and energy from Science Daily Feed - Tue, 08/13/2024 - 12:21pm
Linked to cardiovascular and respiratory diseases in people, nanoplastics continue to build up, largely unnoticed, in the world's bodies of water. The challenge remains to develop a cost-effective solution to get rid of nanoplastics while leaving clean water behind. That's where Mizzou comes in. Recently, researchers created a new liquid-based solution that eliminates more than 98% of these microscopic plastic particles from water.
Categories: Science

Chemists synthesize plant-derived molecules that hold potential as pharmaceuticals

Matter and energy from Science Daily Feed - Tue, 08/13/2024 - 12:21pm
Chemists developed a way to synthesize complex molecules called oligocyclotryptamines, originally found in plants, which could hold potential as antibiotics, analgesics, or anticancer drugs.
Categories: Science

Halogen bonding for selective electrochemical separation, path to sustainable chemical processing demonstrated

Matter and energy from Science Daily Feed - Tue, 08/13/2024 - 11:14am
A team has reported the first demonstration of selective electrochemical separation driven by halogen bonding. This was achieved by engineering a polymer that modulates the charge density on a halogen atom when electricity is applied. The polymer then attracts only certain targets -- such as halides, oxyanions, and even organic molecules -- from organic solutions, a feature that has important implications for pharmaceuticals and chemical synthesis processes.
Categories: Science

New spin on quantum theory forces rethink of a fundamental physics law

New Scientist Feed - Tue, 08/13/2024 - 11:03am
In the quantum realm, a particle’s properties can be separate from the particle itself, including its angular momentum – which could require a rethinking of fundamental laws
Categories: Science

Measuring Martian winds with sound

Matter and energy from Science Daily Feed - Tue, 08/13/2024 - 10:20am
Martian landers have been able capture measurements of wind speeds -- some gauging the cooling rate of heated materials when winds blow over them, others using cameras to image 'tell-tales' that blow in the wind -- but there's still room for improvement. Researchers now demonstrate a novel sonic anemometric system featuring a pair of narrow-band piezoelectric transducers to measure the travel time of sound pulses through Martian air. The study accounted for variables including transducer diffraction effects and wind direction.
Categories: Science

Measuring Martian winds with sound

Space and time from Science Daily Feed - Tue, 08/13/2024 - 10:20am
Martian landers have been able capture measurements of wind speeds -- some gauging the cooling rate of heated materials when winds blow over them, others using cameras to image 'tell-tales' that blow in the wind -- but there's still room for improvement. Researchers now demonstrate a novel sonic anemometric system featuring a pair of narrow-band piezoelectric transducers to measure the travel time of sound pulses through Martian air. The study accounted for variables including transducer diffraction effects and wind direction.
Categories: Science

Say 'aah' and get a diagnosis on the spot: is this the future of health?

Computers and Math from Science Daily Feed - Tue, 08/13/2024 - 10:20am
A computer algorithm has achieved a 98% accuracy in predicting different diseases by analyzing the color of the human tongue. The proposed imaging system can diagnose diabetes, stroke, anemia, asthma, liver and gallbladder conditions, COVID-19, and a range of vascular and gastrointestinal issues, according to new research.
Categories: Science

Delivery robots' green credentials make them more attractive to consumers

Matter and energy from Science Daily Feed - Tue, 08/13/2024 - 10:20am
The smaller carbon footprint, or wheel print, of automatic delivery robots can encourage consumers to use them when ordering food, according to a new study. The suitcase-sized, self-driving electric vehicles are much greener than many traditional food delivery methods because they have low, or even zero, carbon emissions. In this study, participants who had more environmental awareness and knowledge about carbon emissions were more likely to choose the robots as a delivery method. The green influence went away though when people perceived the robots as a high-risk choice -- meaning they worried that their food would be late, cold or otherwise spoiled before it arrived.
Categories: Science

Delivery robots' green credentials make them more attractive to consumers

Computers and Math from Science Daily Feed - Tue, 08/13/2024 - 10:20am
The smaller carbon footprint, or wheel print, of automatic delivery robots can encourage consumers to use them when ordering food, according to a new study. The suitcase-sized, self-driving electric vehicles are much greener than many traditional food delivery methods because they have low, or even zero, carbon emissions. In this study, participants who had more environmental awareness and knowledge about carbon emissions were more likely to choose the robots as a delivery method. The green influence went away though when people perceived the robots as a high-risk choice -- meaning they worried that their food would be late, cold or otherwise spoiled before it arrived.
Categories: Science

Breakthrough in nanotechnology: Viewing the invisible with advanced microscopy

Matter and energy from Science Daily Feed - Tue, 08/13/2024 - 10:19am
Scientists have made a groundbreaking discovery in the field of nanotechnology. They have developed a novel microscopy method that allows for the unprecedented visualization of nanostructures and their optical properties.
Categories: Science

The mother of all motion sensors

Matter and energy from Science Daily Feed - Tue, 08/13/2024 - 10:19am
Researchers have used silicon photonic microchip components to perform a quantum sensing technique called atom interferometry, an ultra-precise way of measuring acceleration. It is the latest milestone toward developing a kind of quantum compass for navigation when GPS signals are unavailable.
Categories: Science

Cricket physics: Science behind the modern bowler technique tricking batters

Matter and energy from Science Daily Feed - Tue, 08/13/2024 - 10:19am
Researchers have started to unravel the mysteries of how near-horizontal bowling in cricket leads to such tough-to-hit balls. The team employed a wake survey rake device made of multiple tubes designed to capture the pressure downstream of the ball and examined the flow dynamics of cricket balls rotating up to 2,500 rpm in a wind tunnel. The group found that low-pressure zones expanded and intensified near the ball when spinning, while these zones shifted and diminished downstream. At higher spin rates, the low-pressure zone begins to change to a persistent bilobed shape. The results lend support to the theory that these newer bowling techniques tap into the Magnus effect.
Categories: Science

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