To try to understand how Earth’s water fits into the history of the planet and the Solar System, researchers examine the isotope ratio on Earth and in meteorites. The isotopic composition of Earth’s water is most similar to primitive meteorites. On the other hand, it’s different from that of comets and nebular gas.

This implies that Earth’s water came from the same cosmochemical reservoir that is also the source of primitive meteorites.

It’s a complicated issue. Maybe Earth’s water has multiple sources. Maybe some of it was created in space long after Earth and the rest of the Solar System formed, and then delivered to Earth.

New research in The Astrophysical Journal explores how water can be created by the solar wind as it strikes surfaces holding oxygen-containing minerals. It’s titled “Stellar Wind Contribution to the Origin of Water on the Surface of Oxygen-containing Minerals.” The lead author is Svatolpuk Civiš from the J. Heyrovský Institute of Physical Chemistry at the Czech Academy of Sciences in Prague.

The solar wind is a steady stream of charged particles—mostly protons and electrons—that come from the Sun. H+ ions, which are simply protons, are the most abundant particles in the solar wind. They make a big contribution to the solar wind’s properties. Could the wind trigger the creation of water molecules?

The researchers performed laboratory experiments to find out. They tested 14 oxygen-containing minerals. “To investigate the process of water formation on the surface of oxidic materials and water abundances, we used the technique of surface bombardment with hydrogen or deuterium atoms and ions,” the authors write in their paper.

The experiments had two phases: the first tested whether the minerals would produce water when exposed to the solar wind, and the second tested their adsorption capacity. Separate from absorption, adsorption is the adhesion of a sample to a surface.

The team produced water and then measured it using two methods: a microwave (MW) discharge experiment and sputter gun irradiation. They tested the results with a type of spectrometry analysis called Fourier-transform infrared spectrometry (FTIR) and temperature-programmed desorption (TPD) analysis.

“Both these experiments include a mineral sample bombarded by hydrogen/deuterium ions, which, among other possibilities, react with surface oxygens in the mineral lattice and form water molecules,” the authors write.

The oxide material samples were not only exposed to the strong current of H, H+ and molecular hydrogen that mimic the solar wind. They were also exposed to intense visible and UV radiation generated in the hydrogen discharge.

“The stellar wind irradiation of rocky oxygen-containing minerals results in a reaction between H+ ions and silicate minerals to produce water and OH, which could explain the presence of water in the regoliths of airless worlds such as the Moon, as well as the water abundances in asteroids,” the authors write.

Previous research has established that a chemical reaction occurs between hydrogen ions and silicate minerals when rocky materials are exposed to solar wind irradiation. Some researchers have observed the formation of OH (hydroxide) and water, while others have only found OH. This research goes deeper by testing the rocky materials for water adsorption.

The researchers tested the samples’ water adsorption capacity. Then, they calculated how much material would need to reach Earth to account for the amount of water on contemporary Earth.

“Besides material acquired by the Earth during accretion, the solar wind origin of water and its delivery to Earth could have gone on even during post-accretional bombardment,” the authors write. Here, they’re referring to the hypothetical Late Heavy Bombardment.

Previous research shows that ” asteroid and comet impacts during the classical Late Heavy Bombardment would bring in about ?10²⁰ kg of material,” the authors write. “If that material’s surface was fully saturated with adsorbed water as composed of one of our minerals, our calculations suggest that at least one ocean equivalent of water could have been brought in.”

There’s not much doubt about the results of these tests and the ability of the solar wind to create water.

“The results of the experiments summarized in this work, focused on surface bombardment with hydrogen atoms, clearly confirm the theory of the interaction of excited hydrogen or deuterium Rydberg atoms and ions with the surface oxygens of oxide minerals,” the authors explain. “Our experiments attempt to explain the origin of water in the areas of oxygen-containing solid material (e.g., dust, meteoroids, asteroids, comets) exposed to a stream of charged particles close to a parent star.”

Earth’s atmosphere and magnetosphere shield it from the solar wind, so there’s no way the wind could’ve created water right on Earth’s surface. However, as the study shows, the wind can create water on the surface of other bodies like asteroids, and the water can be adsorbed and held firm, then delivered to Earth via impacts.

“This scenario is also applicable to the origin of water on Earth,” the authors write. “Due to this effect, a water molecule can be adsorbed on the surface of oxygen-containing particles and then transported over long distances and times,” the researchers write.

This study won’t be the end of the ongoing effort to account for Earth’s water. In a fascinating roundabout way, this research brings us back to asteroids and meteorites delivering Earth’s water. If it can happen here, it can happen on exoplanets elsewhere in the galaxy.

{ https://www.universetoday.com/ }

29-10-2024 om 21:40 geschreven door peter  

This dwarfs the eight days that the Apollo 11 astronauts spent in space. These long trips will tax astronauts’ health and NASA is working to understand what role nutrition can play in helping astronauts stay healthy and manage the risks.

Their current work on astronaut nutrition is a freely available PDF book titled “Human Adaptation to Spaceflight: The Role of Food and Nutrition—2nd Edition.” Its four authors are all researchers working in nutrition, biochemistry, biomedical research, space food systems, and preventative health.

“The importance of nutrition in exploration has been documented repeatedly throughout history, on voyages across oceans, on expeditions across polar ice, and on treks across unexplored continents,” the authors write.

Scientists have learned a lot about nutrition since the age of sailing and exploration, but the authors write that “a key difference between past journeys and space exploration is that astronauts are not likely to find food along the way.” This means that understanding astronaut nutritional requirements and food system requirements on long journeys is “as critical to crew safety and mission success as any of the mechanical systems of the spacecraft itself.”

The book examines the unique challenges astronauts face and presents data from multiple studies that are analogous to those challenges. For example, nutrition research from Antarctica duplicates the isolation and lack of sunlight astronauts can face on long missions, and head-down tilt-bed rest duplicates the musculoskeletal disuse they must endure.

Astronauts face a long list of health risks on long-duration spaceflights. Radiation exposure and its cancer risk and microgravity and its effect on muscle and bone are the most well-known risks. But there are other lesser-known risks, too.

Astronauts can suffer from neuro-ocular syndrome, their immune systems can be weakened, and their gut biota can change. All of these conditions are linked with nutrition. While scientists don’t have a complete understanding of how everything works, it’s clear that nutrition plays a role. The book outlines the types of research being done and what the current understanding is. But the authors are clear about one thing: the system of providing astronauts with proper nutrition needs work.

ISS astronauts, except for Russians, get part of their food in Crew Specific Menu (CSM) containers that each astronaut orders. They provide between 10% and 20% of their food. They also receive a small supply of fresh foods and limited shelf-life foods on each re-supply mission. This has increased the variety of foods for astronauts and helped with nutrition, but astronauts still say they’d like more CSM and fresh foods.

Here in the developed world on Earth, it’s fairly straightforward to meet nutritional needs. Most of us have access to supermarkets and/or farmer’s markets where we can buy fresh produce and other healthy foods. That same variety simply isn’t available in space. ISS astronauts have done some experimental “farming” and have successfully grown a few food plants like lettuce, kale, and cabbage. However, that’s a long way away from growing enough food to help with nutrition, especially on a Mars mission, where presumable space and payload will be at a premium.

One obvious question about astronaut nutrition is whether supplements can replace nutritious food. The authors present evidence that discredits that idea. “Many previous studies have shown that the complex synergistic benefits provided by whole foods cannot be replicated by supplements,” they write. In fact, in some instances, supplements can be dangerous. “Recent studies have also found that supplementation with certain antioxidants such as vitamin E and vitamin A can increase risks of cancer and all-cause mortality,” the authors explain.

The need for a space food system goes beyond nutrition. There are social and well-being benefits, too. Knowing that you have access to a variety of healthy foods keeps morale up. The ability to share or trade high-value food items with your fellow astronauts can create goodwill and a desire to cooperate. Think of sharing a meal with friends or family and all the social connection it provides.

According to the authors, there’s currently no solution to the nutrition roadblock for Mars missions. In fact, there’s currently no system designed to supply astronauts with the needed nutrition for any long-duration spaceflight. “Currently, no food system exists to meet the nutrition, acceptability, safety, and resource challenges of extended exploration missions, such as a mission to Mars,” the authors write.

However, the researchers say it’s critical that we develop one. Without it, long-duration missions and the astronauts who crew them will suffer and possibly face catastrophic failure.

“A space food system, developed and provisioned to deliver all the defined nutritional requirements, should be available on every human mission as an essential countermeasure to health and performance decrements,” the authors write.

{ https://www.universetoday.com/ }

29-10-2024 om 21:28 geschreven door peter  

Story by Holly Bishop

 

Pentagon officials have been left perplexed by a swarm of mystery drones that flew over Langley Air Force base for 17 consecutive nights.

The flock of drones flew in a specific pattern over the base in east Virginia, with one or two-fixed wing drones flying over 100ft in the air, as smaller quadcopters flew below them.

General Mark Kelly, a commander at the airbase, said the drones were almost impossible to catch.

Despite flying across large areas around the base for more than a fortnight in December 2023, the Air Force could not shoot them down due to strict federal laws that stop the military from shooting them down unless they pose a threat.

Some suspect the drones may have originated from Russia or China in an attempt to test American responses.

In a statement, the US Air Force confirmed the breaches but played down the potential threat.

“The number of UASs [uncrewed aerial systems] fluctuated and they ranged in size/configuration," the US Air Force said.

“None of the incursions appeared to exhibit hostile intent but anything flying in our restricted airspace can pose a threat to flight safety. The FAA was made aware of the UAS incursions.”

Analysts noted that the quadcopters did not utilise frequencies typically associated with commercial drones, suggesting they were not operated by hobbyists.

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Due to the sensitive military location, as well as the prolonged nature of the incursions, analysts contacted the White House to help formulate an effective response.

Officials grappled with various options to combat the potential surveillance threat, although all choices have so far been rejected.

One suggestion involved using electronic signals to disrupt the drones' navigation systems, but this was dismissed due to the risk of interfering with Wi-Fi networks and emergency response systems.

Another proposal considered the use of directed energy weapons, an emerging military technology, to shoot down the drones.

However, the Federal Aviation Authority raised concerns about the potential danger to commercial aircraft during the holiday season.

A third option explored was the deployment of nets by the US Coast Guard to capture the drones.

This idea was also rejected due to questions over legal authority and the practical challenges of tracking the swift-moving aircraft.

While the investigation into the Langley incident continues, a potential lead emerged in January when a Chinese student was arrested for unlawfully photographing naval installations.

Fengyun Shi, who was studying at the University of Minnesota, was apprehended whilst attempting to fly back to China.

Shi was caught flying a drone near a shipyard operated by HII, a company responsible for constructing nuclear submarines and the latest Ford Class aircraft carriers.

The student's drone, which had crashed into a tree, contained photos of Navy vessels in dry dock taken around midnight.

During a federal court appearance, Shi's attorney stated: "If he was a foreign agent, he would be the worst spy ever known."

However, the connection between this incident and the Langley drone sightings remains unclear.

The Langley incident is not isolated, as drones have been spotted at other sensitive US military sites.

Just two months prior, the Energy Department's Nevada Nuclear Security Site outside Las Vegas detected five drones over three days.

This location is used for testing nuclear weapons, underscoring the potential security risks posed by such incursions.

These events follow the high-profile Chinese spy balloon incident over Malmstrom Air Force base in Montana, where nuclear assets are stored.

On February 4 last year, the US Air Force responded by dispatching an F-22 fighter jet armed with an AIM-9X Sidewinder missile to take down the balloon over water.

{ https://www.msn.com/en-us/ }

29-10-2024 om 00:46 geschreven door peter  

Mysterious US spaceship executing unprecedented maneuvers above Earth: ‘National security missions in space’

A secretive US spaceship is about to attempt unprecedented flight maneuvers above Earth.

The X-37B Orbital Test Vehicle (OTV-7) is an experimental space plane operated by the United States Space Force (USSF).

Although little has been revealed about the purpose of the vehicle, an official painting of the X-37B unveiled last year depicted the futuristic vehicle intercepting an adversary satellite positioning to disable a friendly satellite.

The US Space Force’s X-37B Orbital Test Vehicle at Kennedy Space Center on Nov. 12, 2022.

U.S Space Force/Boeing / SWNS

USSF have now announced the X-37B will begin executing a series of “novel maneuvers” called aerobraking.

This sees a number of passes using the drag of Earth’s atmosphere to change its orbit around Earth while expending minimal fuel.

If successful, it will allow the X-37B to safely dispose of its service module components in accordance with recognized standards for space debris mitigation.

A rendering showing the spacecraft intercepting an adversary satellite. 

John Ayre/Space Force / SWNS

The X-37B seen at Kennedy Space Center on Oct. 27, 2019. U.S Space Force/Boeing / SWNS

Since December 2023, USSF, supported by the Air Force Rapid Capabilities Office, has conducted radiation effect experiments and has been testing Space Domain Awareness technologies in a “Highly Elliptical Orbit.”

Once the aerobrake maneuver is complete, USSF say the X-37B will “resume its test and experimentation objectives until they are accomplished,” at which time the vehicle will de-orbit and execute a safe return as it has during its six previous missions.

Chief of Space Operations Gen. Chance Saltzman praised the team for its efforts. “This first of a kind maneuver from the X-37B is an incredibly important milestone for the United States Space Force as we seek to expand our aptitude and ability to perform in this challenging domain. The success is a testament to the dedication and perseverance of the team.”

29-10-2024 om 00:28 geschreven door peter  

Earth to Pass Through the Same Taurid Meteor Stream in 2032 That May Have Triggered a Mass Extinction 12,800 Years Ago

Earth will travel right in front of the same Taurid meteor stream in 2032 that caused a mass extinction and worldwide flood ~12,800 years ago, plunging Earth into a mini-Ice Age for 1,300 years. Graham Hancock was right all this time but we did not listen to him.

Our solar system is a dangerous place, and every month Earth inches closer to one of its riskier places, the “Taurid swarm” of meteors. Our planet is predicted to pass directly through the “Taurid swarm” in November 2032.

An ancient monument found in Turkey might be more than just a monument—it could be the world’s oldest solar calendar. Researchers from the University of Edinburgh studied symbols carved on the pillars of Göbekli Tepe, a large, ancient site in southern Turkey. They think these carvings were used to track days, seasons, and years, like a calendar. (Source)

The team noticed that each “V” shape carved on the pillars might represent one day. One pillar even had 365 “V”s, the same number as days in a year. They also found that a special “V” around the neck of a bird-like figure could represent the summer solstice—the longest day of the year. This might explain why the “V” symbol shows up on many other statues in the area, often around the necks of figures connected to time and creation.

Mini Ice Age

The ancient calendar focused on tracking day, night, and seasonal changes, which might have become more important after a major comet hit Earth around 10,850 B.C. This event likely caused a mini-ice age that wiped out many species. According to Martin Sweatman, a researcher from the University of Edinburgh, the people at Gobekli Tepe were careful observers of the sky, possibly because the comet strike had changed their world.

This disaster may have sparked the beginning of civilization by starting new religious beliefs and pushing people to develop agriculture to survive the colder climate. Their carvings might be some of the earliest attempts at writing. These carvings also tracked the cycles of the Moon and Sun, long before similar calendars were made. They may have even shown for the first time that comet strikes are more likely to happen when Earth crosses the path of comet fragments, something that modern scientists have confirmed.

To help support this theory, the team points to another pillar at the site appearing to picture the Taurid meteor stream lasting 27 days, which was quite possibly the source of the ancient comet strike. The researchers believe that the temple carvings show the ancient civilization was recording dates precisely, noting how the movement of constellations across the sky differed based on the time of the year. This would be 10,000 years before Hipparchus of ancient Greece documented the wobble in the Earth’s axis in 150 BC, making this newfound calendar well ahead of its time.

The Younger Dryas boundary (YDB) cosmic-impact hypothesis suggests that around 12,800 years ago, Earth was hit by pieces of a large comet, which broke apart as it entered the inner solar system. This event likely caused a chain reaction, leading to an “impact winter” (a period of intense cold) and a climate change episode called the Younger Dryas (YD). (Source)

The collision is also believed to have caused massive wildfires, the extinction of large animals like mammoths, and changes in human cultures and population decline. Evidence of this impact includes unusually high levels of platinum found at 26 sites across the Northern Hemisphere, including in ice cores from Greenland, which show platinum deposits over a 21-year period.

The start of the Younger Dryas also shows an increase in dust and chemicals linked to wildfires, like ammonium and other burning aerosols, found in ice cores from Greenland, Antarctica, and Russia. These signs point to one of the biggest wildfire events in over 120,000 years, with about 9% of Earth’s forests burned, covering 10 million square kilometers.

This large-scale burning and the cooling effect of the impact may have triggered the Younger Dryas climate change, according to the theory.

A 2021 study (Taurid complex smoking gun) found that 88 near-Earth asteroids, hidden in the debris that creates the Taurid Meteor Shower, likely came from the breakup of a single comet about 20,000 years ago. Astronomers at the University of Antioquia in Colombia studied the ‘Taurid complex’ to learn more about where these objects came from.

In the 1980s, scientists William Napier and Victor Clube noticed large asteroids in the Taurid stream. They suggested these asteroids had the same origin as Comet Encke, which orbits the Sun every three years. However, some asteroids are over a mile wide, meaning they couldn’t have come from Comet Encke itself. Scientists Ignacio Ferrín and Vincenzo Orofino reviewed old research and measured light reflected from the larger asteroids.

They found more evidence that both Comet Encke and the big asteroids came from the breakup of a huge ice comet, 62 miles wide, about 20,000 years ago. The team warned that these asteroids could be dangerous to Earth, and others from the ancient comet might have already hit our planet in the past. Every year, Earth passes through a stream of debris, causing shooting stars to appear in October in the southern hemisphere and November in the north.

Comet Encke, first seen in 1786, left a trail of debris as it got closer to the sun, like other comets. This trail, made up of rocks, dust, and debris, sometimes comes close to Earth, leading to lots of scientific study. Some studies focus on larger asteroids.

Experts think impacts from the Taurid stream may have contributed to the extinction of ancient cultures and global cooling during the Younger Dryas period. The 1908 Tunguska event, where a small asteroid exploded above Russia, destroying millions of trees, is believed to be connected to this debris stream.

In 2013, the Chelyabinsk meteor, which injured over 1,500 people in Russia, may have also come from the Taurid stream. In 2005, NASA astronomer Rob Suggs observed a flash from a meteor hitting the moon, which was part of the Taurid meteor shower.

A team of Colombian researchers, along with astronomers from Italy’s University of Salento, reviewed many studies on space impacts. They confirmed that a group of space objects contains up to 88 large pieces. Using a method called secular light curves, they noticed changes in the brightness of these objects and found that 67% showed signs of “comet-like” activity. This supported the idea that these objects came from a common origin.

Napier, another scientist, supported their findings. He said that these asteroids, which have orbits like Comet Encke, could either be affected by unknown forces or are pieces of a larger, older comet that lost its gases. This original comet may have been a “rubble pile” – a mix of rocks and other materials held together by ice. Over time, this pile could have broken apart, possibly due to forces from the Sun or another object, creating smaller fragments.

One asteroid, Oljato, is an example of a rubble pile. It’s still held together by ice, which gives it comet-like activity, but it’s much smaller than its parent. Bigger inactive objects like Morpheus are similar, but their ice is trapped inside. Smaller objects, like 2006 SO198, might be the original rocky pieces. The team explained that even if an object looks like a regular asteroid, it could still have a comet-like origin.

Taurid meteors, part of this group, are usually larger than normal meteors. They shine brightly and go deeper into the Earth’s atmosphere, sometimes creating fireballs. While this is mostly harmless, the discovery of larger asteroids in one “dangerous” part of the meteor stream could be a real threat.

Earth passes through this risky area every few years, leading to more shooting stars and possibly large objects hitting Earth instead of burning up in the atmosphere. Future encounters are expected in 2022, 2025, 2032, and 2039.

In 2021, David Asher, Armagh Observatory astronomer predicted that in 2032 and 2036 we are likely to pass through the centre of the Taurid complex, where there will be a ‘noticeable enhancement of fireballs.’ According to study [Taurid complex smoking gun] authors Ignacio Ferrín and Vincenzo Orofino, outgassing from comet-like objects within the complex could be hiding smaller, but still potentially dangerous, asteroids that might hit the Earth.

‘The Tunguska cosmic body was 60 to 90 meters in diameter,’ he told Discover Magazine, adding that we ‘now believe the complex may contain many more objects of that size. It is not the tame, simple and innocent complex we thought it was.’

{ https://howandwhys.com/ }

28-10-2024 om 22:15 geschreven door peter  

{ https://scientias.nl/ }

28-10-2024 om 00:00 geschreven door peter  

Earth from space: Bizarre 'pet cloud' reappears above its favorite spot in New Zealand

"As the cloud forms on the crest of this wave, it remains almost stationary in the sky and is shaped by the strong winds blowing through it," John Law, a meteorologist with New Zealand's MetService, told Earth Observatory.

Related: 

• UFO-shaped clouds invade skies over Keck Observatory in Hawaii (photos)

Lenticular clouds are often shaped like flying saucers and are "believed to be one of the most common explanations for UFO sightings across the world," according to the U.K. Met Office.

When viewed side-on, the Taieri Pet often has multiple well-defined layers on top of one another, like a "huge stack of pancakes" or a "pile of plates," Earth Observatory representatives wrote. Past photos of the cloud show it can be several hundred feet tall.

The height of lenticular clouds can make them a surprising aviation risk. Planes can experience severe turbulence when flying through the structures, due to vertical currents that run up and down through the cloud. The clouds' unusually low temperatures also cause ice to form on planes, according to the U.K. Met Office.

ASLCs can be a sign that atmospheric conditions are about to change and are often followed by increased levels of precipitation, according to Fox Weather. However, historical weather data suggest this did not happen in this case.

{ https://www.space.com/ }

27-10-2024 om 23:38 geschreven door peter  

Meltwater beneath Martian Ice Could Support Microbial Life, Researchers Suggest

On Earth, solar radiation can transmit down to multiple meters within ice, depending on its optical properties. Organisms within ice can harness energy from photosynthetically active radiation while being protected from damaging ultraviolet radiation. On Mars, the lack of an effective ozone shield allows approximately 30% more damaging ultraviolet radiation to reach the surface in comparison with Earth. However, new research shows that despite the intense surface ultraviolet radiation, there are radiatively habitable zones within ice in the Martian mid-latitudes, at depths ranging from a few centimeters for ice with 0.01-0.1% dust, and up to a few meters within cleaner ice.

The white edges along these gullies in Mars’ Terra Sirenum are believed to be dusty water ice. Khuller et al. think meltwater could form beneath the surface of this kind of ice, providing a place for possible photosynthesis.

Image credit: NASA / JPL-Caltech / University of Arizona.

“If we’re trying to find life anywhere in the Universe today, Martian ice exposures are probably one of the most accessible places we should be looking,” said Dr. Aditya Khuller, a researcher at NASA’s Jet Propulsion Laboratory.

Mars has two kinds of ice: frozen water and frozen carbon dioxide.

Dr. Khuller and colleagues looked at water ice, large amounts of which formed from snow mixed with dust that fell on the surface during a series of Martian ice ages in the past million years.

That ancient snow has since solidified into ice, still peppered with specks of dust.

Although dust particles may obscure light in deeper layers of the ice, they are key to explaining how subsurface pools of water could form within ice when exposed to the Sun.

Dark dust absorbs more sunlight than the surrounding ice, potentially causing the ice to warm up and melt up to a few feet below the surface.

Mars scientists are divided about whether ice can actually melt when exposed to the Martian surface.

That’s due to the planet’s thin, dry atmosphere, where water ice is believed to sublimate — turn directly into gas — the way dry ice does on Earth.

But the atmospheric effects that make melting difficult on the Martian surface wouldn’t apply below the surface of a dusty snowpack or glacier.

On Earth, dust within ice can create what are called cryoconite holes — small cavities that form in ice when particles of windblown dust (called cryoconite) land there, absorb sunlight, and melt farther into the ice each summer.

Eventually, as these dust particles travel farther from the Sun’s rays, they stop sinking, but they still generate enough warmth to create a pocket of meltwater around them.

The pockets can nourish a thriving ecosystem for simple lifeforms.

“This is a common phenomenon on Earth,” said Dr. Phil Christensen, a researcher at Arizona State University.

“Dense snow and ice can melt from the inside out, letting in sunlight that warms it like a greenhouse, rather than melting from the top down.”

In 2021, the authors discovered dusty water ice exposed within gullies on Mars, proposing that many Martian gullies form by erosion caused by the ice melting to form liquid water.

Their new paper suggests that dusty ice lets in enough light for photosynthesis to occur as deep as 3 m (9 feet) below the surface.

In this scenario, the upper layers of ice prevent the shallow subsurface pools of water from evaporating while also providing protection from harmful radiation.

That’s important, because unlike Earth, Mars lacks a protective magnetic field to shield it from both the Sun and radioactive cosmic ray particles zipping around space.

“The water ice that would be most likely to form subsurface pools would exist in Mars’ tropics, between 30 degrees and 60 degrees latitude, in both the northern and southern hemispheres,” the researchers said.

• The paper appears in the journal Communications Earth & Environment.
• A.R. Khuller et al. 2024. Potential for photosynthesis on Mars within snow and ice. Commun Earth Environ 5, 583; doi: 10.1038/s43247-024-01730-y
• This article is a version of a press-release provided by NASA.

{ https://www.sci.news }

27-10-2024 om 22:59 geschreven door peter  

Scientists may have found clues to a mysterious fifth force of nature hidden in an ancient asteroid

An asteroid's orbit may reveal an invisible fifth force that could rewrite the rules of physics.

byTibi Puiu

Bennu, a near-Earth asteroid first discovered in 1999, has now become an unlikely tool in the search for something extraordinary — a fifth fundamental force of nature that could rewrite the rules of the universe.

For decades, scientists have understood the cosmos through the lens of four forces: gravity, electromagnetism, and the strong and weak nuclear forces. But for just as long, there have been whispers of a missing piece, a fifth force, waiting to be discovered. Now, with the help of Bennu, a team of international scientists believes they are inching closer to solving one of physics’ biggest mysteries.

The Search For The Fifth Force

In 2023, on a sunny morning in the Utah desert, a spacecraft returned to Earth after one of the most epic journeys in the history of human exploration. It made a trek of more than two billion miles. Inside was a capsule containing a treasure from the distant past: a sample of rock and dust from an ancient asteroid named Bennu.

Bennu is a spinning-top-shaped asteroid just 500 meters wide. It’s like a time capsule that holds the secrets of our solar system’s formation dating back over 4.5 billion years. Made of loose rubble, Bennu is thought to contain primordial compounds, including organic molecules that may have contributed to the rise of life on Earth. When the OSIRIS-REx spacecraft touched down on its surface in October 2020, it gathered these fragments, which could shed light on the building blocks of our own planet.

The data from that mission has already been a treasure trove for planetary science. But for physicists like Yu-Dai Tsai from Los Alamos National Laboratory, Bennu’s path through space offers something more: a chance to detect an invisible hand shaping its motion.

“Interpreting the data we see from tracking Bennu has the potential to add to our understanding of the theoretical underpinnings of the universe,” Tsai said.

His team’s study suggests that small, barely detectable deviations in Bennu’s orbit could signal the presence of a fifth force — a force that might help explain dark matter, the mysterious substance that makes up most of the universe but remains unseen.

In many ways, this is not a new idea. Physicists have been on the hunt for a fifth force since the 1980s. They’ve imagined it as everything from a form of antigravity to a cosmic essence they dubbed “quintessence,” thought to explain the universe’s accelerating expansion. But the precise movements of Bennu offer a rare, controlled environment to test this idea in real time.

Anomalies

Here’s how it works: as Bennu orbits the Sun, it is pulled by gravity, nudged by solar radiation, and impacted by tiny forces we can’t see. Imagine playing a game of billiards, but every ball moves with a slight, invisible push. You would start to suspect that the table was slightly tilted — even if you couldn’t see the tilt. That ’tilt’ is essentially what Tsai and his team are trying to uncover.

The researchers studied Bennu’s exact orbit using data from OSIRIS-REx and earlier ground-based observations. They then asked: Is there anything in Bennu’s path that doesn’t quite add up? Could there be a subtle force, too small to measure directly, but strong enough to alter the asteroid’s journey?

“The trajectories of objects often feature anomalies that can be useful in discovering new physics,” said Tsai. Indeed, this kind of detective work has yielded scientific breakthroughs before. In the mid-1800s, astronomers used tiny irregularities in the orbit of Uranus to predict the existence of Neptune — decades before they had the telescopic power to spot it directly through a lens.

But there’s a catch. For every Neptune, there’s also a Vulcan. That was the name for a hypothetical planet that scientists once believed existed between Mercury and the Sun, used to explain oddities in Mercury’s orbit. Turns out, it didn’t exist at all (though it made for good Star Trek lore).

A Window Into Dark Matter?

Bennu might not hold all the answers, but it’s giving researchers an important clue. In their analysis, Tsai’s team didn’t find evidence of a fifth force — yet. What they did find were some of the most stringent limits ever placed on how strong or far-reaching such a force could be.

If this fifth force exists, it’s hiding very well. The team was able to rule out certain models of fifth forces that rely on particles known as ultralight bosons. Some physicists believe these bosons could reveal dark matter.

Dark matter, the invisible substance that makes up roughly 85 percent of all matter in the universe, has long eluded scientists. We know it’s there because galaxies spin faster than they should based on their visible matter alone—something is holding them together. But what that “something” is remains one of science’s greatest enigmas. Finding a fifth force could provide a much-needed breakthrough.

Eyes on Apophis

Bennu may not have cracked the case, but it’s just the beginning. Tsai’s team plans to continue their work by studying Apophis, another near-Earth asteroid that will make a spectacularly close flyby in 2029, passing within just 20,000 miles of our planet. NASA’s OSIRIS-APEX mission will track Apophis as it zooms by, and the team hopes it will provide even better data to test for the elusive fifth force.

“The tight constraints we’ve achieved translate to some of the tightest-ever limits on Yukawa-type fifth forces,” said Sunny Vagnozzi, a cosmologist from the University of Trento and a co-author on the study, referring to the mathematical framework used to describe these forces.

For now, though, the search continues. As this research shows, asteroids aren’t mere space debris, but could hold the key to forces we can’t see — but which shape everything around us.

• The findings appeared in the journal Communications Physics.

{ https://www.zmescience.com/ }

26-10-2024 om 21:34 geschreven door peter  

Nu komeet C/2023 A3 (Tsuchinshan–ATLAS) helder aan de hemel staat, neemt ook in Nederland en België het aantal waarnemingen toe. Dit bijzondere hemellichaam, eerder dit jaar ontdekt door de observatoria in China en Zuid-Afrika, was aanvankelijk alleen zichtbaar vanuit zuidelijker gelegen gebieden. Maar na zijn passage langs de zon in september schittert de komeet nu aan de nachthemel en biedt een prachtige kans voor waarnemers op het noordelijk halfrond. Vanaf 12 oktober kunnen kijkers in Nederland en België de komeet bewonderen, vooral in de vroege avond.

C/2023 A3 heeft een lange en bewogen reis achter de rug, waarbij zijn zichtbaarheid en helderheid onzeker waren door mogelijke fragmentatie en veranderingen in zijn kernstructuur. De komeet bleek echter bestand tegen de hitte en straling van de zon en komt nu steeds dichter bij de aarde. Dankzij zijn nabijheid en helderheid is de komeet al met het blote oog te zien en gedetailleerd te observeren met een verrekijker of camera.

Op deze eerste foto, gemaakt door Arnold van Rooij uit Zutphen, zien we komeet C/2023 A3 op een heldere herfstavond boven de horizon verschijnen. Deze opname, gemaakt op 14 oktober om 20:00 CEST, toont de opvallende helderheid, vorm, coma en stofstaart van de komeet die zijn reis aan onze hemel vervolgt:

Hieronder een selectie van bijzondere opnamen van de komeet, die de diversiteit en pracht van C/2023 A3’s passage aan de hemel laten zien, zowel vanuit Nederland als daarbuiten:

Op 23 oktober maakte de Vlaamse Volkssterrenwacht Urania uit Hove (Antwerpen), België onderstaande livestream van de komeet met een presentatie over de komeet:

• https://youtu.be/48fe8QquU0o

Comet C/2023 A3 Tsuchinshan-ATLAS at its closest to the Earth: online observation – 12 Oct. 2024.

Onderstaande videobeelden werden gemaakt op 12 oktober vanuit Manaukea (Hawaii), V.S., met de NAOJ Subaru Telescoop:

• https://youtu.be/CctFLzGqMJo

Comet C/2023 A3 Tsuchinshan-ATLAS at perihelion: online observation – 28 Sept. 2024

Videobeelden SOHO

De zonnekijker die zich later ontpopte tot een kometenjager: het verhaal van de Solar and Heliospheric Observatory (SOHO) ruimtetelescoop. Zoals de naam al weggeeft was SOHO van origine vooral bedoeld om de zon en en diens corona te observeren en doet dit nog steeds, hoewel met een andere functie; het traceren van kometen -ideaal voor de passage van C/2023 A3-. Middels SOHO is dan ook onderstaande video gemaakt, waarop de passage van de komeet rond de Zon zich toont, een opname die plaatsvond in de periode 7 oktober t/m 13 oktober jl.:

Comet C/2023 A3 brightens SOHO’s week (standard processing)

Zelf waarnemen

Wil je zelf een blik werpen op de komeet vanuit Nederland of België? Dat kan! Want sinds 12 oktober staat de komeet hoog genoeg aan onze horizon en passeert het dichtst bij de aarde op 0,47 AE, (ongeveer 71 miljoen kilometer). Wel met een verrekijker, en steeds vlak na zonsondergang. Sinds 21 oktober is de komeet het gunstigst te zien vanuit onze streken.

Je kunt op de onderstaande sterrenkaart de passage volgen door de sterrenbeelden Slang, Slangendrager en Adelaar van 12 oktober tot aan de jaarwisseling, wanneer de komeet te ver van de zon verwijderd zal zijn om nog zichtbaar te zijn. Zie voor tijdentabellen en meer over het volgen van de komeet hemel.waarnemen.com of TheSkyLive.com.

Mocht je zelf spectaculaire foto’s (hebben) weten te maken van de komeet, en je wilt deze graag delen met Scientias.nl, dan staan we daar zeker voor open! Wellicht herpubliceren wij deze in een later artikel met jouw toestemming; upload of link jouw opname in de reacties hieronder, of email deze aan de moderator (op hoge kwaliteit liefst) incl, je naam, datum en plaats van opname en wat je nog meer kwijt wilt.

• De afgelopen decennia hebben ruimtetelescopen en satellieten prachtige foto’s gemaakt van nevels, sterrenstelsels, stellaire kraamkamers en planeten. Ieder weekend halen we een indrukwekkende ruimtefoto uit de archieven. Genieten van alle foto’s? Bekijk ze op deze pagina.

Bronmateriaal

• "Erwin" - x.com
• "Josh Dury B.A FRAS" - x.com
  
• "Wouter van Bernebeek" - x.com
  
• "LIVESTREAM - Komeet C/2023 A3 (Tsuchinshan-ATLAS)" - Youtube
  
• "C/2023 A3 Comet Tsuchinshan-ATRLAS over Maunakea, Hawaii" - Youtube
  
• "Comet C/2023 A3 brightens SOHO’s week (standard processing)" - Youtube
  
• "C-2023_A3_Tsuchinshan-ATLAS" - hemel.waarnemen.com
  
• Afbeelding bovenaan dit artikel: Arnold van Rooij, lezer van Scientias.nl

{ https://scientias.nl/ }

26-10-2024 om 21:22 geschreven door peter  

Rotsachtige planeten die om kleinere sterren cirkelen, kunnen namelijk een atmosfeer hebben die stabiel genoeg is om leven te ondersteunen.

Onderzoekers maakten vorige week bekend dat ze hebben gezocht naar tekenen van leven in het TRAPPIST-1-systeem. Met behulp van de Allen Telescope Array hebben ze 28 uur lang het hele systeem doorgespit op zoek naar radiosignalen die mogelijk van buitenaardse technologie afkomstig zijn. Helaas leverde de zoektocht naar aliens uiteindelijk niets op. Maar dat sluit de mogelijkheid van leven rond deze nabije ster nog niet uit, zo stelt een nieuwe studie nu.

TRAPPIST-1
Het TRAPPIST-1-systeem bestaat uit een kleine, koele ster (een zogenoemde rode dwerg, zie kader) op ongeveer 41 lichtjaar afstand van de aarde. Dit systeem herbergt zeven rotsachtige planeten, waarvan er enkele zich in de bewoonbare zone bevinden. In deze zone kunnen de omstandigheden geschikt zijn voor vloeibaar water, een essentieel element voor leven zoals wij dat kennen. Om deze redenen is TRAPPIST-1 een belangrijke bestemming in de zoektocht naar leven buiten de aarde.

Meer over rode dwergsterren
Rode dwergsterren (M-sterren) zijn de meest voorkomende en langstlevende sterren in het heelal. Ze zijn een stukje kleiner en koeler dan onze eigen zon. Rode dwergen blijken vaak, zoals dus ook bij TRAPPIST-1 het geval is, rotsachtige planeten te herbergen. En sommige van deze aardachtige werelden draaien ook nog eens in de leefbare zone. Al deze ingrediënten samen maken rode dwergen erg interessant in de zoektocht naar buitenaards leven.

Ondanks al deze gunstige aspecten hebben eerdere studies twijfels geuit over de bewoonbaarheid van de planeten in het TRAPPIST-1-systeem. Dat heeft vooral te maken met de sterke UV-straling waar planeten die rond rode dwergsterren draaien, mee worden gebombardeerd. Deze straling kan tot wel honderden duizenden keren sterker kan zijn dan wat de aarde van de zon ontvangt. Dit kan er vervolgens voor zorgen dat het oppervlaktewater weg brandt. Dit zou leiden tot een uitgedroogd oppervlak en, als alleen het waterstof uit de waterdamp ontsnapt, een ophoping van reactief zuurstof kunnen veroorzaken. Dit laatste zou de chemie die nodig is voor het ontstaan van leven in de weg staan. Over de kansen om leven te vinden rond rode dwergen zijn onderzoekers dan ook niet meer zo optimistisch.

Zoektocht naar aliens
Maar nu toont een nieuwe studie aan dat de zoektocht naar aliens rondom TRAPPIST-1 niet helemaal tevergeefs is geweest. Zo stellen onderzoekers nu dat rotsachtige planeten die rond rode dwergsterren draaien, toch een atmosfeer kunnen ontwikkelen die op lange termijn stabiel is. “Een van de meest fascinerende vragen in de exoplaneetastronomie is of rotsachtige planeten rond rode dwergsterren in staat zijn om hun atmosfeer te behouden die leven kunnen ondersteunen”, zegt hoofdauteur Joshua Krissansen-Totton. “Onze resultaten wijzen erop dat sommige van deze planeten inderdaad een atmosfeer kunnen hebben, wat de kans vergroot dat deze veelvoorkomende planetaire systemen levensvatbaar zijn.”

James Webb
Sinds de lancering eind 2021 heeft de James Webb-ruimtetelescoop de kans vergroot om tekenen van leven op exoplaneten, oftewel planeten buiten ons zonnestelsel, te ontdekken. Deze ruimtetelescoop is gevoelig genoeg om een aantal rode dwergster-systemen te observeren, waaronder het TRAPPIST-1-systeem. Tot nu toe suggereren gegevens dat de heetste rotsachtige planeten, die zich dicht bij de TRAPPIST-1-ster in de buurt bevinden, geen significante atmosfeer hebben. De telescoop heeft echter nog niet de mogelijkheid gehad om de planeten in de leefbare zone – die verder van hun ster liggen en de meest gunstige afstand voor vloeibaar water en leven bieden – duidelijk te karakteriseren.

Bewoonbare zone
De bewoonbare of leefbare zone is het gebied dat zich op een dusdanige afstand bevindt van een ster dat er eventueel leven mogelijk is. Belangrijkste voorwaarde daarbij is de temperatuur. Het moet er niet te warm of te koud zijn, zodat water niet bevriest of verdampt, maar vloeibaar blijft. Leuk weetje: dit gebied wordt ook wel de Goldilocks-zone genoemd, naar het sprookje van Goudlokje en de drie beren. Volgens het verhaal moet een meisje van drie borden pap proeven, waarbij het eerste te warm is, het tweede te koud en het derde precies goed.

Om te achterhalen of planeten in deze leefbare zone ook daadwerkelijk leefbaar zijn, hebben de onderzoekers in de nieuwe studie een rotsachtige planeet gemodelleerd terwijl deze zich in de gesmolten fase bevond en gedurende honderden miljoenen jaren afkoelde tot een vaste, aardachtige planeet. De resultaten laten zien dat waterstof en andere lichte gassen aanvankelijk naar de ruimte ontsnapten. Voor planeten verder van de ster vandaan, waar de temperatuur gematigder is, reageerde waterstof echter met zuurstof en ijzer in het binnenste van de planeet. Dit resulteerde in de vorming van water en andere zwaardere gassen, waardoor een atmosfeer ontstond die stabiel blijft in de loop der tijd.

Gematigde planeten
Kortom, de kans dat sommige planeten rondom TRAPPIST-1 leven herbergen, is best reëel. “Het is gemakkelijker voor Webb om de heetste planeten die dicht bij de ster staan te observeren, omdat ze meer thermische straling uitstralen, die minder wordt verstoord door de ster zelf”, aldus Krissansen-Totton. “Voor deze planeten hebben we een duidelijke conclusie: ze hebben geen dikke atmosfeer. Daarentegen kunnen de meer gematigde planeten mogelijk wel een atmosfeer hebben. Dit betekent dat ze nauwkeurig met telescopen onderzocht moeten worden, vooral vanwege hun potentie om bewoonbaar te zijn.”

De James Webb-telescoop heeft zoals gezegd nog niet kunnen vaststellen of de planeten die iets verder van de TRAPPIST-1-ster liggen een atmosfeer hebben. Maar als dat het geval is, zou dat betekenen dat ze vloeibaar water aan de oppervlakte en een gematigd klimaat kunnen hebben, wat gunstig zou zijn voor het ontstaan van leven. Krissansen-Totton betoogt dan ook dat het de moeite waard is om rotsachtige planeten die zich in de bewoonbare zone van het TRAPPIST-1-systeem bevinden, grondiger te bestuderen. Alleen zo zullen we definitief kunnen vaststellen of deze planeten inderdaad een atmosfeer en omstandigheden hebben die geschikt zijn voor leven.

Bronmateriaal

• "Rocky planets orbiting small stars could have stable atmospheres needed to support life" - University of Washington
• Afbeelding bovenaan dit artikel: via Canva Pro

{ https://scientias.nl/ }

26-10-2024 om 20:57 geschreven door peter  

NASA's Curiosity Rover may have found evidence of life on Mars

On the barren, cold expanses of Mars, a discovery has rocked the scientific world. The recent Mars rover unmanned mission has uncovered mud formations that tell tales of wet and dry spells spanning millions of years.

Could this revelation enhance the argument for life having existed on Mars? According to the research paper titled ‘Sustained wet-dry cycling on early Mars’ published in the prestigious peer-reviewed journal Nature, the answer looks promising.

The Hexagonal Clues

At the core of this breakthrough is the discovery of distinctive hexagonal patterns. These shapes, as scientists understand them, emerge when regions experience extended periods of wetness followed by prolonged dryness.

While it's been acknowledged that Mars holds remnants of dried rivers, lakes, and even seas – a testament to its once wet environment, the finding that Mars underwent wet-dry cycles multiple times potentially revolutionizes our understanding of the planet's past and its suitability for life.

Beyond the Ordinary: The Y-Shaped Cracks

Another highlight of the finding is the uniqueness of the mud formations. While past explorations revealed ‘T’ shaped mud cracks, this mission has, for the first time, unveiled hexagonal ‘Y’ shaped formations on Mars. Such patterns aren’t just intriguing geometrically, but they indicate a notably long sequence of wet and dry epochs, shedding light on Mars’ climatic history.

However, their existence also poses a question: Why weren’t they detected earlier? The answer lies in their vulnerability. ‘Y’ formations are extremely prone to erosion, potentially explaining their elusive nature up until now.

Gearing Up for the Hunt for Martian Life

The implications of this discovery are far-reaching. With knowledge about Mars' wet-dry cycles and the conditions most conducive to life, the scientific community is better equipped than ever before in the search for extraterrestrial life.

The newfound mud formations, bearing clues of possible organic activity, have given researchers a more targeted area to investigate. It's a massive step forward in our relentless quest to determine if Mars ever hosted life forms, even if they were just microscopic entities.

Mars, often seen as our desolate neighboring planet, continues to unravel its mysteries, challenging our perceptions and fueling our curiosity. Each discovery brings us closer to understanding not just Mars, but the broader universe and our place within it.

The Mars rover mission's latest findings are not just about unique mud formations; they're about the potential stories these formations hold, stories of life's resilience, adaptability, and the infinite possibilities that lie beyond our Earthly realm.

Note: Materials provided above by The Brighter Side of News. Content may be edited for style and length.

• Like these kind of feel good stories? Get The Brighter Side of News' newsletter.

{ https://www.thebrighterside.news/ }

26-10-2024 om 20:39 geschreven door peter  

{ https://www.universetoday.com/ }

05-10-2024 om 16:45 geschreven door peter  

It’s not long before a conversation about space travel is likely to turn to the impact on the human body. Our bodies have evolved to exist on Earth with a constant force of 1G acting upon them but up in orbit, all of a sudden that force is apparently lacking. The impact of this is well known; muscle loss and reduction in bone density but there are effects of spaceflight. Cosmic radiation from the Galaxy has an impact on cognition too, an effect that has recently been studied in mice!

When an object like the space station is in orbit around the Earth it is in a state known as freefall. This means it is constantly falling to Earth but the curvature of the Earth is constantly falling away from it. In other words, it is constantly falling but never reaches the ground. This state means anyone or anything inside the space station would also fall at the same rate but this would be experienced as floating. Muscle loss and reduction in bone density are the well known impacts of such an environment but there are more that await a space traveller. 

Galactic cosmic radiation (GCR) is made up of energy originating from sources outside of our Solar System. These tend to be from supernova explosions and other energetic events in deep space. The particles from GCR are mostly protons and electrons along with some heavier nuclei. They can penetrate our atmosphere but the Earth’s magnetic field offers some protection to those on the surface. To those venturing out into space, things are a little less rosey for GCR can have quite an impact on astronauts. 

GCR is a real problem for longer duration space exploration like trips to Mars since currently, the radiation can penetrate spacecraft shielding and be a real threat to human health. Studies to date have shown that GCR can have an effect cognitive abilities on mice in the short term however a new study paints a rather more bleak picture. The paper published in the Journal of Neurochemistry reports that GCR exposure can have long lasting effects too. 

Surprisingly, the team studied the impact on both male and female mice by subjecting them to a multi-particle spectrum GCR similar to the radiation that would be experienced on a deep space mission. The experiment was undertaken at Brookhaven National Laboratory where a 33-ion beam was used to simulate radiation from space. The team found that the radiation impaired numerous central nervous system functions from memory, pattern separation (when the brain minimises overlap between patterns of neuronal activity that represents similar experiences), anxiety, vigilance, social novelty (tendency to spend time with a previously unknown mouse rather than a familiar mouse!) and motor controls.

The discovery that the impact on females was more pronounced was unexpected but the team also established that mice which were fed an antioxidant and anti-inflammatory drugs known as CDDO-EA were less effected. The findings will be of immediate benefit to space exploration but will also help us to understand the long term impact on our cognition from radiation.

Source : 

• Can cosmic radiation in outer space affect astronauts’ long-term cognition?

{ https://www.universetoday.com/ }

05-10-2024 om 16:37 geschreven door peter  

(Photo : UTokyo | 東京大学/ X) Living microbes found in 2-billion-year-old rock from South Africa could be a time capsule to the early evolution of life on Earth and improve our chances of finding evidence of life on Mar.

A sealed rock fracture almost 50 feet below ground has remained home to microbes for the last 2 billion years—the oldest life ever discovered in such conditions. The nearly 1-foot sample, excavated beneath South Africa’s Bushveld Igneous Complex, predates the previous microbial record-holders by as much as 1.9 billion years. The finding could help researchers better understand the earliest stages of evolutionary life not just on Earth, but on Mars, as well.

The findings, published October 2 in the journal Microbial Ecology, come from a team at the University of Tokyo’s Department of Earth and Planetary Sciences, who confirmed the previous oldest known lifeforms in 2020.

“We didn’t know if 2-billion-year-old rocks were habitable… so this is a very exciting discovery,” Yohey Suzuki, study lead author and an associate professor in the University of Tokyo’s Graduate School of Science, said in a statement on Thursday.

Uncovering microbes hidden from the surface world for eons required building upon the researchers’ previous methodologies for determining an organism’s age and origin. Doing so required combining three types of imaging approaches—electron microscopy, fluorescent microscopy, and infrared spectroscopy—to confirm if the microbial life really was that old, or if it came from accidental contamination during excavation and analysis. After staining the cells’ DNA, researchers looked at the microbes’ proteins as well as their surrounding clay habitat, and determined them to be both alive and native to the fissure sample.

How the microbes have been able to continue existing longer than almost any other life on Earth likely comes in large part from their habitat. Located in northeastern South Africa, the Bushveld Igneous Complex (BIC) is a roughly 41,000-square-mile region known for rich deposits of ore, including an estimated 70 percent of all mined platinum. Billions of years ago, volcanic magma cooled incrementally beneath the Earth’s surface in regions as thick as 5.6 miles.

These formations have remained largely unchanged since then, but also include tiny fissures in which microbial life became densely packed. At the same time, clay sediment capped any gaps near these cracks, trapping the tiny organisms inside while allowing nothing else to enter. Experts theorize that allowed the stability for microbial life to continue at an extremely slow pace with little-to-no evolutionary changes. With further exploration, the team hopes to detail what some of the planet’s earliest life looked like billions of years before the arrival of humans.

A rock structure scientists at University College London believe could contain the earliest fossils of life ever found.

(UCL)

Future findings aren’t necessarily limited to expanding our understanding of how organisms evolved on Earth over time. The research team hopes their additional discoveries can one day also help search for evidence of life on Mars.

“NASA’s Mars rover Perseverance is currently due to bring back rocks that are a similar age to those we used in this study,” Suzuki explained. “Finding microbial life in samples from Earth… makes me excited for what we might be able to now find in samples from Mars.”

{ https://www.msn.com/en-us/ }

05-10-2024 om 16:24 geschreven door peter  

Scientists begin testing space thruster that could boldly go where no one has gone before

by University of Southampton

Deep space exploration might no longer be confined to sci-fi after scientists began testing a rocket thruster which promises to boldly go further than ever before.

Astro engineers from the University of Southampton are trialing a new propulsion system which can power spaceships through the stars using any type of metal as fuel.

They say this means crafts fitted with the technology could fly indefinitely by refilling their tanks using minerals harvested from asteroids or far-off moons.

Lead scientist Dr. Minkwan Kim, from the University of Southampton, has been tasked with testing the propulsion system in his labs to measure its thrust.

He said the tech could help spaceships and probes travel to regions of the universe previously thought unreachable.

Dr. Kim added, "Spacecraft have limited amounts of fuel because of the enormous cost and energy it takes to launch them into space.

"But these new thrusters are capable of being powered by any metal that can burn, such as iron, aluminum or copper.

"Once fitted, spacecraft could land on a comet or moon, rich in these minerals, and harvest what it needs before jetting off with a full tank.

"It could open up vast new frontiers and accelerate our understanding of the universe."

Once blasted above the Earth's atmosphere, spacecraft are mostly propelled by rare gas phase fuels such as xenon or krypton, which also power the Starlink satellites.

Scientists from Southampton are working with British-based space firm Magdrive on the propulsion system. The technology is named Super Magdrive.

Dr. Kim, who created a plasma thruster design for the SpaceX Falcon 9 rocket launched last year, said he hopes the tech can be used for future deep-space missions.

He added, "The system could help us explore new planets, seek out new life, and go where no human has gone before—enabling never-ending discovery."

{ https://phys.org/space-news/ }

05-10-2024 om 16:09 geschreven door peter  

Lunar Ice Deposits are More Extensive than Previously Thought

Prior studies found signs of ice in the permanently shadowed regions near the south pole of the Moon, including areas within Cabeus, Haworth, Shoemaker and Faustini craters. A new analysis of data from NASA’s Lunar Reconnaissance Orbiter (LRO) shows there is widespread evidence of water ice within permanently shadowed regions outside the south pole, towards at least 77 degrees south latitude.

This illustration shows the distribution of permanently shadowed regions (in blue) on the Moon poleward of 80 degrees south latitude. They are superimposed on a digital elevation map of the lunar surface (gray) from the Lunar Orbiter Laser Altimeter instrument on board NASA’s Lunar Reconnaissance Orbiter.

Image credit: NASA / GSFC / Timothy P. McClanahan.

Ice could become implanted in lunar regolith through comet and meteor impacts, released as vapor (gas) from the lunar interior, or be formed by chemical reactions between hydrogen in the solar wind and oxygen in the regolith.

The permanently shadowed regions (PSRs) typically occur in topographic depressions near the lunar poles.

Because of the low Sun angle, these areas haven’t seen sunlight for up to billions of years, so are perpetually in extreme cold.

Ice molecules are thought to be repeatedly dislodged from the regolith by meteorites, space radiation, or sunlight and travel across the lunar surface until they land in a PSR where they are entrapped by extreme cold.

The PSR’s continuously cold surfaces can preserve ice molecules near the surface for perhaps billions of years, where they may accumulate into a deposit that is rich enough to mine.

“Our model and analysis show that greatest ice concentrations are expected to occur near the PSRs’ coldest locations below 75 Kelvin (minus 198 degrees Celsius, or minus 325 degrees Fahrenheit) and near the base of the poleward-facing slopes of PSRs,” said Dr. Timothy McClanahan, a researcher at NASA’s Goddard Space Flight Center.

“We can’t accurately determine the volume of the PSRs’ ice deposits or identify if they might be buried under a dry layer of regolith.”

“However, we expect that for each surface 1 m² residing over these deposits there should be at least about five more liters of ice within the surface top 1 m, as compared to their surrounding areas.”

Dr. McClanahan and colleagues used LRO’s Lunar Exploration Neutron Detector (LEND) instrument to detect signs of ice deposits by measuring moderate-energy, ‘epithermal’ neutrons.

Specifically, they used LEND’s Collimated Sensor for Epithermal Neutrons (CSETN) that has a fixed 30-km (18.6 mile) diameter field-of-view.

Neutrons are created by high-energy galactic cosmic rays that come from powerful deep-space events such as exploding stars, that impact the lunar surface, break up regolith atoms, and scatter subatomic particles called neutrons.

The neutrons, which can originate from up to about a 1-m (3.3-foot) depth, ping-pong their way through the regolith, running into other atoms. Some get directed into space, where they can be detected by LEND.

Since hydrogen is about the same mass as a neutron, a collision with hydrogen causes the neutron to lose relatively more energy than a collision with most common regolith elements.

So, where hydrogen is present in regolith, its concentration creates a corresponding reduction in the observed number of moderate-energy neutrons.

“We hypothesized that if all PSRs have the same hydrogen concentration, then CSETN should proportionally detect their hydrogen concentrations as a function of their areas,” Dr. McClanahan said.

“So, more hydrogen should be observed towards the larger-area PSRs.”

• The findings were published this week in the Planetary Science Journal.
• T.P. McClanahan et al. 2024. Evidence for Widespread Hydrogen Sequestration within the Moon’s South Pole Cold Traps. Planet. Sci. J 5, 217; doi: 10.3847/PSJ/ad5b55
• This article was adapted from an original release by NASA.

{ https://www.sci.news/ }

05-10-2024 om 15:58 geschreven door peter  

The asteroid that killed the dinosaurs was NOT alone: Scientists discover evidence that a second devastating space rock smashed into Earth 66 million years ago

• READ MORE: The 6 catastrophic asteroids on course to crash into Earth 

By Shivali Best For Mailonline 

It's well known that the reign of the dinosaurs came to an end when a giant asteroid smashed into Earth 66 million years ago.

But a new study suggests that this huge asteroid wasn't alone.

Scientists from Heriot Watt University have discovered evidence that a second devastating space rock smashed into Earth in the same year.

This second asteroid measured around 1,640ft (500 metres) wide, and struck Earth just off the coast of the Republic of Guinea in West Africa.

'The closest humans have come to seeing something like this is the 1908 Tunguska event, when a 50-metre asteroid entered Earth's atmosphere and exploded in the skies above Siberia,' said Dr Uisdean Nicholson, who led the study.

It's well known that the reign of the dinosaurs came to an end when a giant asteroid smashed into Earth 66 million years ago. But a new study suggests that this huge asteroid wasn't alone (stock image) 

The first evidence of this second asteroid was uncovered in 2022, while Dr Nicholson and his team were studying seismic reflection data of the Atlantic Ocean's seabed.

The data revealed a depression measuring almost five miles (9km) deep, which the team suspected could be an asteroid impact crater.

Now, the researchers have taken new high-resolution, 3D seismic images of the depression, which have confirmed their suspicions.

The crater has been dubbed the Nadir Crater, and was carved out when an asteroid struck Earth around 66 million years ago – the same age as the dinosaur-killing asteroid.

'There are around 20 confirmed marine craters worldwide, and none of them has been captured in anything close to this level of detail. It's exquisite,' Dr Nicholson said.

Now, the researchers have taken new high-resolution, 3D seismic images of the depression, which have confirmed their suspicions

Scientists from Heriot Watt University have discovered evidence that a second devastating space rock smashed into Earth in the same year as the one that wiped out the dinosaurs

'Craters on the surface are usually heavily eroded and we can only see what is exposed, whereas craters on other planetary bodies usually only show the surface expression.

'These data allow us to image this fully in three dimensions and peel back the layers of sedimentary rock to look at the crater at all levels.'

Back in 2022, the researchers suggested that the asteroid would have been around 400 metres wide.

However, the new images confirm that it was even bigger than this.

Dr Nicholson said: 'We now think it was 450-500m wide, because of the larger crater size as shown by the 3D data.

'We can tell it came from about 20-40 degrees to the northeast, because of spiralling thrust-generated ridges surrounding the crater's central peak - those are only formed following a low-angle oblique impact.

'And we think it would have hit Earth at about 20 km per second, or 72,000 km per hour, although we still need to confirm this with a new set of impact models.'

This second asteroid measured around 1,640ft (500 metres) wide, and struck Earth just off the coast of the Republic of Guinea in West Africa (Nadir Crater, pictured) 

Based on the data, the scientists have created a timeline of what they think happened – from the initial collision to an 800-metre-plus high tsunami that would have travelled across the Atlantic ocean.

'After the impact and the central uplift forming, the soft sediments surrounding the crater flowed inwards towards the evacuated crater floor, creating a visible "brim",' Dr Nicholson explained.

'The earthquake shaking caused by the impact appears to have liquefied the sediments below the seabed across the entire plateau, causing faults to form below the seabed.

'The impact was also associated with large landslides as the plateau margin collapsed below the ocean.

'As well as this, we see evidence for a train of tsunami waves going away from, then back towards the crater, with large resurge scars preserving evidence of this catastrophic event.'

While it's been 116 years since an asteroid like this has been seen, it likely won't be long before another huge space rock strikes our planet, according to NASA.

The US space agency predicts that asteroid Bennu has a one in 2,700 chance of smashing into Earth on 24 September 2182.

HOW THE DINOSAURS BECAME EXTINCT AROUND 66MILLION YEARS AGO

Dinosaurs ruled the Earth around 66million years ago, but suddenly disappeared in what is known as the Cretaceous-Tertiary extinction.

It was believed for many years that the changing climate destroyed the food chain of the huge reptiles. 

However, in the 1980s paleontologists discovered a layer of iridium - an element that is rare on Earth but found in vast quantities in space.  

When this was dated, it coincided precisely with when the dinosaurs disappeared from the fossil record. 

A decade later, scientists uncovered the massive Chicxulub Crater at the tip of Mexico’s Yucatán Peninsula, which dates to the period in question. 

Scientific consensus now says that these two factors are linked and they were both probably caused by an enormous asteroid crashing to Earth.

With the projected size and impact velocity, the collision would have caused an enormous shock wave and is likely to have triggered seismic activity. 

The fallout would have created plumes of ash thought to have covered the whole planet, making it impossible for dinosaurs to survive. 

Other animals and plant species had a shorter time-span between generations which allowed them to survive.

There are several other theories as to what caused the demise of the dinos. 

One early theory was that small mammals ate dinosaur eggs and another proposes that toxic angiosperms (flowering plants) killed them off.  

The Day the Mesozoic Died: The Asteroid That Killed the Dinosaurs — HHMI BioInteractive Video

The Permian Extinction

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04-10-2024 om 00:21 geschreven door peter  

© Credit: NASA

Earth and the Moon – A Distant View
Taken on September 18, 1977, Voyager 1 became the first spacecraft to capture both Earth and its Moon in a single frame. At a distance of 7.25 million miles from Earth, this iconic image shows the Moon floating beyond our home planet, emphasizing the vastness of space.1

• Read More: The Mystery of The Indian Ocean's ‘Gravity Hole'

© Credit: NASA

Jupiter's Great Red Spot
In early 1979, Voyager 1 provided a close-up of Jupiter’s Great Red Spot, a storm larger than Earth. This swirling mass of clouds, first observed centuries ago, gave scientists new insight into Jupiter’s turbulent atmosphere, thanks to the detailed images captured by Voyager.

© Credit: NASA

Active Volcanism on Io
During its flyby of Jupiter's moon Io, Voyager 1 discovered something unprecedented-active volcanoes. This was the first observation of volcanic activity on another celestial body besides Earth. Voyager detected plumes erupting miles into space, revealing Io’s fiery surface.

© Credit: NASA

Saturn's Breathtaking Rings
Voyager 1 reached Saturn in 1980, capturing stunning images of its intricate ring system. Saturn’s rings, composed of countless ice and rock particles, revealed a beauty never before seen. Voyager even discovered a new, faint G-ring and enigmatic spokes in the B-ring.2

© Credit: NASA

Titan's Hazy Atmosphere
As Voyager 1 flew past Saturn's largest moon, Titan, it detected a thick atmosphere primarily composed of nitrogen. Titan's opaque haze left its surface hidden, fueling speculation about the moon's geological secrets. This image offered a glimpse into one of the most mysterious moons in our solar system.

© Credit: NASA

The Pale Blue Dot
Perhaps the most famous image Voyager 1 ever captured is the “Pale Blue Dot,” taken on February 14, 1990, from 3.7 billion miles away. In this image, Earth appears as a tiny speck, less than a pixel in size, suspended in a sunbeam. Carl Sagan's reflections on this image remind us of our small place in the vast universe.

• Read More: NASA Discovered a Potentially Habitable Planet – An Alternative To Mars?

© Credit: NASA

Close-up of Europa
Voyager 1 also flew by Jupiter's moon Europa, capturing images of its icy surface. The close-up showed evidence of potential subsurface oceans, raising the possibility of life beneath its frozen crust. These images set the stage for future missions to study Europa more closely.

© Credit: NASA

Voyager 1's Family Portrait of the Solar System
In 1990, Voyager 1 captured a family portrait of the solar system from beyond Pluto. This composite image includes six planets: Jupiter, Saturn, Uranus, Neptune, Earth, and Venus. It’s a striking reminder of our solar system’s expanse and the spacecraft’s journey far from home.

© Credit: NASA

Saturn's Moons – Tethys, Dione, and Rhea
Voyager 1 captured images of Saturn's moons Tethys, Dione, and Rhea in 1980, showcasing their cratered surfaces and icy landscapes. These moons, though small, are integral parts of Saturn's complex system of rings and satellites.

© Credit: NASA

The F Ring of Saturn
One of the discoveries made by Voyager 1 was the narrow, braided F ring of Saturn. This stunning image shows the intricacies of the ring's structure, including its twists and clumps, revealing a dynamic system shaped by gravitational interactions with Saturn's moons.

© Credit: NASA

Entering Interstellar Space
In 2012, Voyager 1 became the first human-made object to enter interstellar space, crossing the heliopause-the boundary between the solar wind and interstellar medium. The spacecraft's data showed a steep drop in solar particles and a rise in cosmic rays, confirming this historic milestone.

© Credit: NASA

A Golden Message to the Cosmos

Voyager 1 carries the Golden Record, a 12-inch disc containing sounds and images from Earth. This record, curated by Carl Sagan and his team, serves as a message to any intelligent life that might find it, showcasing humanity's diversity and curiosity.

© Credit: NASA

Beyond the Solar System
Voyager 1's journey continues today, traveling at 38,000 miles per hour into interstellar space. Though its power is diminishing, the data it sends back from beyond the solar system gives us unprecedented insight into the universe beyond the Sun's influence.

© Credit: NASA

Conclusion
Voyager 1's images, from the close-up of Jupiter's Great Red Spot to the distant Pale Blue Dot, have changed our understanding of the cosmos. As it continues its journey through interstellar space, this remarkable spacecraft reminds us of humanity's quest for discovery beyond the stars.

Read More: If a ‘Planet Killer' Astroid is Going to Hit Earth, This is How NASA Will Warn The World

Sources

• “Astonishing Images: What Voyager 1 Really Saw in its 47-Year-Journey to Interstellar Space..” Secrets of Universe. Rishabh Nakra.
• “Voyager: 15 incredible images of our solar system captured by the twin probes (gallery).” Space. Daisy Dobrijevic and Mike Wall. September 22, 2022.
  

The post 13 Astonishing Images Taken By Voyager 1 On Its Way to Interstellar Space appeared first on The Hearty Soul.

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03-10-2024 om 00:56 geschreven door peter  

Geoscientists Discover Mysterious Subduction Zone beneath Pacific Ocean

During the Mesozoic era, between 250 and 120 million years ago, an ancient seafloor sank deep into Earth in the East Pacific Rise, a tectonic plate boundary on the floor of the southeastern Pacific Ocean, says a team of geoscientists from the University of Maryland and the University of Alberta.

A map of the East Pacific Rise region where the discovery of an ancient seafloor was made.

Image credit: Jingchuan Wang.

University of Maryland researcher Jingchuan Wang and colleagues used innovative seismic imaging techniques to peer deep into Earth’s mantle, the layer between our planet’s crust and core.

They found an unusually thick area in the mantle transition zone, a region located between about 410 and 660 km below the Earth’s surface.

The zone separates the upper and lower mantles, expanding or contracting based on temperature.

The newly-discovered seafloor may also explain the anomalous structure of the Pacific Large Low Shear Velocity Province (LLSVP) — a massive region in Earth’s lower mantle — as the LLSVP appears to be split by the slab.

“This thickened area is like a fossilized fingerprint of an ancient piece of seafloor that subducted into the Earth approximately 250 million years ago,” Dr. Wang said.

Recent findings by scientists reveal an ancient seafloor that complicates current theories of Earth’s interior, discovered through pioneering seismic imaging that highlights unusual mantle activities.

(Artist’s concept.) Credit: SciTechDaily.com

“It’s giving us a glimpse into Earth’s past that we’ve never had before.”

Subduction occurs when one tectonic plate slides beneath another, recycling surface material back into Earth’s mantle.

The process often leaves visible evidence of movement, including volcanoes, earthquakes and deep marine trenches.

While geologists typically study subduction by examining rock samples and sediments found on Earth’s surface.

By examining how seismic waves traveled through different layers of Earth, the researchers were able to create detailed mappings of the structures hiding deep within the mantle.

“You can think of seismic imaging as something similar to a CT scan. It’s basically allowed us to have a cross-sectional view of our planet’s insides,” Dr. Wang said.

“Usually, oceanic slabs of material are consumed by the Earth completely, leaving no discernible traces on the surface.”

“But seeing the ancient subduction slab through this perspective gave us new insights into the relationship between very deep Earth structures and surface geology, which were not obvious before.”

What the authors found surprised them: material was moving through Earth’s interior much more slowly than previously thought.

An illustrative diagram showing the ancient subducted ‘slab’ the team resolved at present day. It has a direct impact on the large-scale lowermost mantle structures known as ‘superplumes’.

Credit: Jingchuan Wang, University of Maryland

The unusual thickness of the area they discovered suggests the presence of colder material in this part of the mantle transition zone, hinting that some oceanic slabs get stuck halfway down as they sink through the mantle.

Example of subduction processes in the Atlantic. 

(Science Photo Library/Getty Images)

“We found that in this region, the material was sinking at about half the speed we expected, which suggests that the mantle transition zone can act like a barrier and slow down the movement of material through the Earth,” Dr. Wang said.

“Our discovery opens up new questions about how the deep Earth influences what we see on the surface across vast distances and timescales.”

• The results were published in the journal Science Advances.
• Jingchuan Wang et al. 2024. Mesozoic intraoceanic subduction shaped the lower mantle beneath the East Pacific Rise. Science Advances 10 (39); doi: 10.1126/sciadv.ado1219

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02-10-2024 om 23:39 geschreven door peter